Plants as a source of natural antioxidants.pdf

Plants as a Source of Natural Antioxidants

Plants as a Source of Natural Antioxidants
Edited by
Nawal Kishore Dubey
Banaras Hindu University, India

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Library of Congress Cataloging-in-Publication Data
Plants as a source of natural antioxidants / edited by Nawal Kishore Dubey,
Banaras Hindu University, India.

pages cm
Includes bibliographical references and index.
ISBN 978-1-78064-266-6 (alk. paper)
1. Materia medica, Vegetable. 2. Antioxidants -- Health aspects.
3. Antioxidants -- Therapeutic use. I. Dubey, N.K.
RS164.P728 2014
615.3’28--dc23
2014002483
ISBN-13: 978 1 78064 266 6
Commissioning editor: Sreepat Jain
Editorial assistant: Alexandra Lainsbury
Production editor: Shankari Wilford
Typeset by SPi, Pondicherry, India
Printed and bound in the UK by CPI Group (UK) Ltd, Croydon, CR0 4YY

Contents
Contributors vii
Preface ix
1 Plants of Indian Traditional Medicine with Antioxidant Activity 1
Nawal Kishore Dubey, Akash Kedia, Bhanu Prakash and Nirmala Kishore
2 Natural Antioxidants from Traditional Chinese Medicinal Plants 15
Li Sha, Li Shu-Ke, Li Hua-Bin, Xu Xiang-Rong, Li Fang,
Wu Shan and Li An-Na
3 Review of the Antioxidant Potential of African Medicinal and Food Plants 34
Sunday E. Atawodi, Olufunsho D. Olowoniyi, Godwin O. Adejo and
Mubarak L. Liman
4 Antioxidant Plants from Brazil 97
Nádia Rezende Barbosa Raposo, Annelisa Farah Silva and
Hudson Caetano Polonini
5 Antioxidant Characteristics of Korean Edible Wild Plants 110
Sang-Uk Chon and Kyeong-Won Yun
6 Algae as a Natural Source of Antioxidant Active Compounds 129
Emad A. Shalaby
7 Antioxidant Potential of Marine Microorganisms: A Review 148
Vashist N. Pandey, Sarad K. Mishra, Abhai K. Srivastava and Nidhi Gupta
8 Biotechnologies for Increasing Antioxidant Production from Plants 156
Sanath Hettiarachi and Priyani Lakshmi Hettiarachchi
9 Plant-derived Antioxidants as Food Additives 169
Dimitris P. Makris and Dimitrios Boskou
10
Biochemical Activity and Therapeutic Role of Antioxidants
in Plants and Humans 191
Neha Pandey and Shashi Pandey-Rai
v

vi Contents
11 Pharmacology of Medicinal Plants with Antioxidant Activity 225
Archana Mehta
12 Endophytic Fungal Associations of Plants and Antioxidant Compounds 245
Suresh C. Sati and Savita Joshi
13
Mycorrhizal Symbiosis in the Formation of Antioxidant
Compounds 252
Pranaba Nanda Bhattacharyya and Dhruva Kumar Jha
14
Role of Mushrooms as a Reservoir of Potentially Active Natural Antioxidants:
An Overview 282
Sikha Dutta
Index 295

vii
Contributors
Godwin O. Adejo, Biochemistry Department, Ahmadu Bello University, Zaria, Nigeria. E-mail:
adejogod@yahoo.com
Sunday E. Atawodi, Biochemistry Department, Ahmadu Bello University, Zaria, Nigeria.
E-mail: atawodi_se@yahoo.com
Pranaba Nanda Bhattacharyya, Tocklai Tea Research Institute, Tea Research Association, Jorhat
785008, Assam, India. E-mail: pranabananda_01@rediffmail.com
Dimitrios Boskou, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki,
Greece. E-mail: boskou@chem.auth.gr
Sang-Uk Chon, EFARINET Co. Ltd, ~883 Yangsan-Dong, Buk-Gu, Gwangju 500-895, Republic
of Korea. E-mail: choncn@nate.com
Nawal Kishore Dubey, Department of Botany, Banaras Hindu University, Varanasi-221005,
India. E-mail: nkdubeybhu@gmail.com or nhdubey2@rediffmail.com
SikhaDutta,DepartmentofBotany,UGCCentreofAdvancedStudies,TheUniversityofBurdwan,
Burdwan-713104, West Bengal, India. E-mail: sikha_bu_bot@yahoo.com
Nidhi Gupta, Experimental Botany and Nutraceutical Laboratory, Department of Botany,
D.D.U. Gorakhpur University, Gorakhpur-273009, India. E-mail: nidhig.ddu@gmail.com
Sanath Hettiarachi, Department of Biological Sciences, Rajarata University of Sri Lanka,

Mihintale, Sri Lanka. E-mail: sanath.hetti@gmail.com
Priyani Lakshmi Hettiarachchi, Department of Biological Sciences, Rajarata University of
Sri Lanka, Mihintale, Sri Lanka. E-mail: phlakshmi@yahoo.com
Dhruva Kumar Jha, Microbial Ecology Laboratory, Department of Botany, Gauhati University,
Guwahati-781014, Assam, India. E-mail: dkjha_203@yahoo.com or dkjhabot07@gmail.com
Savita Joshi, Department of Botany, D.S.B. Campus, Kumaun University, Nainital-263002,
India. E-mail: savijoshi@ymail.com
Akash Kedia, Department of Botany, Banaras Hindu University, Varanasi-221005, India.
E-mail: akashkedia28@gmail.com
Nirmala Kishore, Department of Botany, Banaras Hindu University, Varanasi-221005, India.
E-mail: niluvats@rediffmail.com
Li An-Na, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department
of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China.
E-mail: lianna28@live.cn
Li Fang, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of
Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China.
E-mail: fionali1216@163.com

viii Contributors
Li Hua-Bin, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department
E-mail: lihuabin@mail.sysu.edu.cn
Li Sha, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of
Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China.
E-mail: lisha0308@hotmail.com
Li Shu-Ke, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department
E-mail: lishuke19880818@126.com
Mubarak L. Liman, Biochemistry Department, Ahmadu Bello University, Zaria, Nigeria.
E-mail: mubarak.liman@gmail.com
Dimitris P. Makris, Department of Food Science and Nutrition, University of theAegean, Myrina,
Lemnos, Greece. E-mail: dmakris@aegean.gr
Archana Mehta, Department of Botany, School of Biological Sciences, Dr. H.S. Gour University,
Sagar-470003 (M.P.), India. E-mail: archuunisagar@rediffmail.com
SaradK.Mishra,DepartmentofBiotechnology,D.D.U.GorakhpurUniversity,Gorakhpur-273009,
India. E-mail: saradmishra5@gmail.com
Olufunsho D. Olowoniyi, Biochemistry Department, Ahmadu Bello University, Zaria, Nigeria.
E-mail: dayofun@yahoo.com
Neha Pandey, Laboratory of Morphogenesis, Centre of Advanced Study in Botany, Department of
Botany, Banaras Hindu University, Varanasi-221005, India. E-mail: nehapandey87@gmail.com
Vashist N. Pandey, Experimental Botany and Nutraceutical Laboratory, Department of Botany,
D.D.U. Gorakhpur University, Gorakhpur-273009, India. E-mail: vnpgu@yahoo.co.in
Shashi Pandey-Rai, Laboratory of Morphogenesis, Centre of Advanced Study in Botany,
Department of Botany, Banaras Hindu University, Varanasi-221005, India. E-mail: shashi.
bhubotany@gmail.com
Hudson Caetano Polonini, NUPICS (Núcleo de Pesquisa e Inovação em Ciências da Saúde),
Universidade Federal de Juiz de Fora, Brazil. E-mail: h.c.polonini@gmail.com
Bhanu Prakash, Department of Botany, Banaras Hindu University, Varanasi-221005, India.
E-mail: Bhanubhu08@gmail.com
Nádia Rezende Barbosa Raposo, NUPICS (Núcleo de Pesquisa e Inovação em Ciências da
Saúde), Universidade Federal de Juiz de Fora, Brazil. E-mail: nadiafox@gmail.com
Suresh C. Sati, Department of Botany, D.S.B. Campus, Kumaun University, Nainital-263002,
India. E-mail: satisc2000@yahoo.co.in
Emad A. Shalaby, Biochemistry Department, Faculty of Agriculture, Cairo University, Giza
12613, Egypt. E-mail: dremad2009@yahoo.com or emad2e0m0a1d@yahoo.com
Annelisa Farah Silva, NUPICS – Núcleo de Pesquisa e Inovação em Ciências da Saúde, Univer-
sidade Federal de Juiz de Fora, Brazil. E-mail: silva_af@yahoo.com.br
Abhai K. Srivastava, Experimental Botany and Nutraceutical Laboratory, Department of Botany,
D.D.U. Gorakhpur University, Gorakhpur-273009, India. E-mail: aks.nature@gmail.com
Wu Shan, Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department
E-mail:wushansw@sina.com
Xu Xiang-Rong, Key Laboratory of Marine Bio-resources Sustainable Utilization, South China
Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
E-mail: xuxr@scsio.ac.cn
Kyeong-Won Yun, Department of Oriental Medicine Resources, Sunchon National University,
Suncheon 540-950, Republic of Korea. E-mail: ykw@sunchon.ac.kr

ix
Preface
Reactive oxygen species (ROS), which are also known as active oxygen species (AOS) and

reactive oxygen intermediates (ROI) are formed as by-products of oxidative metabolism.
In addition to metabolism, harmful radiation and attacks by pathogens also induce the forma-
tion of ROS. These free radicals, as is evident from their various names, are highly reactive and
many can start chain reactions that form yet more free radicals. All types of cell components
are at risk of oxidative damage from free radicals. In humans, this type of damage can cause
various degenerative conditions that may lead to cancer and cell ageing. Hence, antioxidants
have a positive effect on general health in humans who, in addition to their endogenous anti-
oxidants, take in a considerable amount of antioxidants with the diet. As these molecules are
not food per se, but have health effects, they are called nutraceuticals.
There is presently an increased interest worldwide in identifying antioxidant compounds
that are pharmacologically effective and have low or no side effects for use in preventive medi-
cine and the food industry. Plants are susceptible to damage caused by active oxygen, and
produce a significant amount of various antioxidant (or potentially antioxidant) compounds
(in addition to tocopherols). These compounds include flavonoids, other phenolic compounds
and polyphenolics (condensed and hydrolysable tannins, lignin precursors). Such compounds
can prevent the oxidative stress caused by the production of ROS, act as ROS-scavenging com-
pounds and provide broad-spectrum protection against oxidative radicals. Ayurveda, Unani,
Chinese and other traditional medicine systems provide a substantial lead into finding active
and therapeutically useful antioxidant compounds from plants, as does research on the phyto-
chemistry of plants with antioxidant activity. Indeed, many aromatic, medicinal and spice
plants have been confirmed to contain compounds with strongly antioxidative components.
The aim of the book is to provide up-to-date basic information on antioxidant plants from
different sources and on the role of different abiotic and biotic stresses, endophytes and mycor-
rhizal fungi in the development of antioxidant compounds in plants. There is also discussion
of transgenic approaches to the scavenging of ROS, and of the antioxidant plants used in dif-
ferent therapeutic systems. Overall, the book throws light on the different medicinal and aro-
matic plants that have the potential to be used as antioxidants. It will be an excellent reference
for medical practitioners, botanists, phytochemists, pharmacologists, microbiologists, biotech-
nologists and herbal drug researchers and practitioners. The book will also serve as a compre-
hensive overview of traditional and current knowledge on the health effects of plant-based
antioxidants and, bearing in mind the side effects of synthetic antioxidants, will be relevant to
the advancing back to nature movement of today’s world.

x Preface
The book has been devised as a ‘one-stop platform’ comprising a perfect blend of compre-
hensive information on plants as a source of natural antioxidants. It has 14 chapters contrib-
uted by eminent scientists working in the field of antioxidants and natural products. These
cover most aspects of plant-based antioxidants, focusing on up-to-date information contrib-
uted by world experts in the field and taking a global look at the subject. The chapters include
information on traditionally used antioxidants from different biodiversity rich countries, and
on the antioxidant potential of algae, endophytic fungi, marine microorganisms, mushrooms
and mycorrhizal fungi, as well as plants themselves. In addition, pharmacological, biochem-
ical, biotechnological and industrial aspects have also been covered, Further, as a result of the
interdisciplinary specialization that there is within various fields, an attempt has been made to
provide a pertinent collection of references on the subject of natural antioxidants within a single
volume.
I am very grateful to the contributors for their timely responses in the production of the
book, in spite of their busy academic schedules, and wish to express my gratitude to them all
for providing their excellent chapters. Without their full cooperation, this work would not
have been possible.
My wife, Dr Nirmala Kishore, has always been my intellectual companion and provided
me with constant inspiration in bringing out the book. My beloved daughter, Dr Vatsala
Kishore MD, and my son, Navneet Kishore, have always provided me with unmatched help
and sacrifices. I also bow my head to my father, Sri G.N. Dubey, mother, Smt Shanti Devi, and
father-in-law, Prof. Ram Deo Shukla, for their blessings and encouragement. My sincere thanks
are also due to my research students, Archana, Priyanka, Bhanu, Prashant, Akash, Abhishek
and Manoj, for their help and cooperation.
Thanks are also due to CABI Publishers for publishing the book, taking the utmost interest
and providing helpful assistance and understanding. Special thanks go to Dr Sreepat Jain, the
Commissioning Editor, who initially motivated me to bring out this book and has provided his
full support, and also to Alexandra Lainsbury, Editorial Assistant at CABI.
N.K. Dubey

© CAB International 2015. Plants as a Source of Natural Antioxidants (ed. N.K. Dubey) 1
1.1 Introduction
Free radicals are chemical species that have
one or more unpaired electrons, as a result of
which they are highly unstable and can cause
damage to other molecules by extracting elec-
trons from them in order to attain stability.
Among them are reactive oxygen species (ROS)
that include superoxide radicals,
hydroxyl rad-
icals, singlet oxygen and hydrogen peroxide,
which are often generated as by-products of
biological reactions but can also be derived
from exogenous factors (Cerutti, 1991). Some
ROS have positive biological roles, in processes
such as energy production, phagocytosis,
regulation of cell growth, intercellular signal-
ling and synthesis of biologically important
compounds (Halliwell, 1997). Often though,
they can induce the oxidation of lipids, caus-
ing membrane damage and decreasing mem-
brane fluidity. ROS can also lead to cancer via
DNA mutations (Cerutti, 1991, 1994; Pietta,
2000), and to abnormal ageing and neurode-
generative diseases (Beal, 1995).
The amounts of ROS present in an organ-
ism can be regulated by synthesizing enzymes
such as endogenous superoxide dismutase,
glutathione peroxidase and catalase, or by
non-enzymatic antioxidants such as ascorbic
acid (vitamin C), α-tocopherol (vitamin E),
glutathione (GSH), carotenoids, flavonoids,
etc. Sies (1993) has examined these strategies.
As already noted, the overproduction of re-
active species, induced by exposure to exter-
nal oxidant substances, or by a failure in the
usual defence mechanisms, can lead to the
development of degenerative diseases (Shahidi
et al., 1992); these include cardiovascular dis-
eases, cancers (Gerber et al., 2002), neurode-
generative diseases (for instance Alzheimer’s
disease; Di Matteo and Esposito, 2003) and
inflammatory diseases (Sreejayan and Rao,
1996). In particular, the hydroxyl radical is
known to react with all of the components of
DNA (Halliwell and Gutteridge, 1999), with
the polyunsaturated fatty acid residues of
phospholipids (Siems et al., 1995) and with
the side chains of all amino acid residues of
proteins, especially cysteine and methionine
residues (Stadtman, 2004).
One solution to this major problem is to
supplement the diet with antioxidant com-
pounds that are found in natural plant sources
(Knekt et al., 1996). Plants produce antioxi-
dants to counter the oxidative stress caused by
the production of ROS during photosynthesis
and thus represent a source of new anti
oxidant compounds. The traditional Indian
1 Plants of Indian Traditional Medicine
with Antioxidant Activity
Nawal Kishore Dubey,* Akash Kedia, Bhanu Prakash
and Nirmala Kishore
Department of Botany, Banaras Hindu University,
Varanasi, India
*Corresponding author. E-mail address: nkdubeybhu@gmail.com

2 N.K. Dubey et al.
medicine system of Ayurveda has a special
branch called rasayana in which disease is
prevented and the ageing process counter-
acted through the optimization of home
ostasis. Some of the plants used in rasayana
preparations have been found to be 1000 times
more potent than ascorbic acid, α-tocopherol,
and probucol in their antioxidant activity
(Scartezzini and Speroni, 2000).
In recent years, the use of natural anti-
oxidants present in traditional medicinal
plants has become of special interest in the
scientific world due to their presumed safety
and nutritional and therapeutic value (Ajila,
et al., 2007). This contrasts with the synthetic
antioxidants that are commonly used in pro-
cessed foods, such as butylated hydroxytol-
uene (BHT) and butylated hydroxyanisole
(BHA), which have side effects and have
been reported to be carcinogenic (Ito et al.,
1983). The majority of the antioxidant activ-
ity of plants is due to the presence of phen-
olic compounds (flavonoids, phenolic acids
and alcohols, stilbenes, tocopherols, tocot-
rienols), ascorbic acid and carotenoids. Re-
cent reports have indicated that there is an
inverse relationship between the dietary in-
take of antioxidant-rich foods and the inci-
dence of human disease, so it seems that
natural plant antioxidants can serve as a
type of preventive medicine. A large number
of plants worldwide have been found to
have both strong antioxidant activity (Baratto
et al., 2003) and powerful scavenger activity
against free radicals (Kumaran and Karuna-
karan, 2007).
India is a land of multiple geographical
regions, and its flora, with more than 45,000
plant species, represents 7% of the world’s flora.
Out of this vast number of plant species, me-
dicinal plants comprise approximately 8000
species, and account for about 50% of all the
Indian higher flowering plant species and
11% of total known world flora (Ali et al., 2008).
A number of these Indian medicinal plants
have been used in the traditional Ayurveda
system of medicine for thousands of years.
Ayurveda (literally ayus, life, and veda, know-
ledge; hence science of life) is the oldest med-
ical system in the world and has been practised
in India for more than 3500 years. The first
recorded book on Ayurvedic medicine was
Acharya Charak’s Charaka Samhita (600 bc),
and traditional healers have used this resource
since time immemorial for the benefit of hu-
mankind. Other ancient Indian literature is
also a source of information on the medicinal
properties of herbal plants and preparations
that have been found to be effective in the
treatment of various diseases, as detailed in
the Glossary of Indian Medicinal Plants (Chopra
et al., 1956). The more modern manifestation
ofAyurvedaisMaharishiAyurveda(Glaser, 1988).
The World Health Organization (WHO)
has estimated that almost 80% of the earth’s in-
habitants believe in traditional medicine for
their primary health care needs, and that most
of this therapy involves the use of plant extracts
and their active components (
Winston, 1999).
A number of plants and plant products have
medicinal properties that have been
validated
by recent scientific developments throughout
the world, owing to their potent pharmaco-
logical activity, low toxicity and economic via-
bility. A plethora of literature is available on
traditional Indian medicinal plants with anti-
oxidant activity (Scartezzini and Speroni, 2000;
Ali et al., 2008). This chapter reviews the anti-
oxidant activity of such traditional Indian
medicinal plants based on a literature survey.
1.2 Some Traditionally used Antioxidant
Plants and Methods Used for
Screening Them
Ayurveda, whose efficacy has been approved
by the WHO (Zaman, 1974) provides an ap-
proach to prevention and treatment of differ-
ent diseases by a large number of medical
procedures and pharmaceuticals. There is a
long list of traditional Indian medicinal plants
that show antioxidant activity when screened
by different methods. Table 1.1 presents a se-
lection of such plants as reported by different
researchers, with brief details of the assay
methods and plant preparations used for each;
further information on the methods mentioned
in the table is given below.
A number of methods have been de-
scribed by different workers for testing the
antioxidant activity of medicinal plants (see
Ali et al., 2008 and Krishnaiah et al., 2011).

Plants
of
Indian
Traditional
Medicine
3
Table 1.1. List of some Indian medicinal plants having antioxidant activity.
Botanical name
Common
name Preparation/solvent used
Method used to measure
antioxidant activitya
Reference
Aerva lanata (L.) Schult Pindi kura Ethanol extract of whole plant DPPH assay Shirwaikar et al., 2004
Amaranthus paniculatus L. Rajgriha Aqueous extract of whole plant DPPH assay Amin et al., 2006
Amaranthus viridis L. Chowlai Methanol extract of leaf and seed DPPH assay Iqbal et al., 2012
Aporosa lindleyana Baill. Kodali Petroleum ether, chloroform, ethyl
acetate and methanol extract
of root
DPPH and nitric oxide radical
inhibition assays
Badami et al., 2005
Baliospermum montanum
(Willd.) Muell.
Danti Methanolic leaf extract DPPH and ABTS assay Seethalaxmi et al., 2012
Coriandrum sativum L. Coriander Methanol and aqueous extract
of leaf and stem
DPPH assay Wong and Kitts, 2006
Cynodon dactylon (L.) Pers. Dhub grass Ethanolic extract and water
infusion of whole plant
Lipid peroxidation and ABTS assay Auddy et al., 2003
Cyperus rotundus L. Nut grass Ethyl acetate extract of whole
plant
DPPH assay Kilani et al., 2005
Dendrocnide sinuata (Blume)
Chew
Fever nettle Methanol and aqueous extract
of leaves
DPPH assay Tanti et al., 2010
Desmodium gangeticum (L.) DC Shalaparni 50% aqueous alcoholic extract
of aerial part
DPPH, nitric oxide, hydrogen peroxide
scavenging activity
Govindarajan et al., 2003
Evolvulus alsinoides L. Morning glory Ethanolic extract and water
Lipid peroxidation and ABTS Auddy et al., 2003
Ficus microcarpa L. Indian laurel Methanol extract of bark DPPH and ABTS assay Ao et al., 2008
Hygrophila auriculata
(Schumach.) Heine
Gokulakanta Aqueous extract of root FTC and TBA methods Shanmugasundaram and
Venkataraman, 2006
Ipomoea reptans (Linn.) Poir. Water spinach Aqueous extract of leaf DPPH, hydroxyl, superoxide radicals
and lipid peroxidation assay
Dasgupta and De, 2007
Kigelia pinnata (Jacq.) DC. Sausage tree Methanol extract of aerial parts DPPH assay Patel et al., 2010
Momordica charantia L. Bitter gourd Aqueous extract of leaf, stem,
green fruit and ripe fruit
DPPH, FRAP and β-carotene linoleate
bleaching assay
Kubola and Siriamornpun, 2008
Moringa oleifera Lam. Drumstick 50% aqueous extract of leaf β-carotene linoleate bleaching assay Reddy et al., 2005
Nyctanthes arbor-tristis L. Harsingar Ethyl acetate extract of leaf DPPH, hydroxyl, superoxide radical
and H2
O2
scavenging assays
Rathee et al., 2007
Continued

4
N.K.
Dubey
et
al.
Table 1.1. continued.
Botanical name
Common
name Preparation/solvent used
Method used to measure
antioxidant activitya
Reference
Phyllanthus amarus Schum.
and Thonn.
Bahupatra Methanol extract of whole plant DPPH, superoxide radical and H2
O2
scavenging activity
Kumaran and Karunakaran,
2007
Phyllanthus debilis Klein ex Willd. Niruri DPPH, superoxide radical and H2
O2
scavenging activity
2007
Phyllanthus maderaspatensis L. Bhumyamalki Methanol extract of whole plant DPPH, superoxide radical and H2
O2
scavenging activity
2007
n-hexane extract of whole plant Inhibition of lipid peroxidation Asha et al., 2004
Phyllanthus niruri L. Pitirishi Methanolic and aqueous extract
of leaves and fruits
LPO and DPPH methods Chatterjee et al., 2006
Phyllanthus urinaria L. Stone breaker Methanol extract of whole plant DPPH, superoxide radical and H2
O2
scavenging activity
Kumaran and Karunakaran
(2007)
Phyllanthus virgatus G. Forst. Seed-under-
leaf
Methanol extract of whole plant DPPH, superoxide radical and H2
O2
scavenging activity
Kumaran and Karunakaran
(2007)
Plumbago zeylanica L. Chitrak Aqueous extract of aerial parts ABTS assay Natarajan et al. (2006)
Polyalthia cerasoides (Roxb.)
Bedd.
Kudumi Methanolic leaf extract DPPH assay Ravikumar et al., 2008
Sida cordifolia L. Flannel weed Ethanolic extract and water
Lipid peroxidation and ABTS assays Auddy et al., 2003
Striga orobanchioides Benth. Witchweed Ethanolic extract of whole plant DPPH and nitric oxide radical
inhibition assays
Badami et al., 2003
Terminalia chebula Retz. Harara Aqueous extract of fruits DPPH and ABTS assays Naik et al., 2003
Tinospora cordifolia Miers Giloy Aqueous extract of root TBA assay Prince and Menon, 1999
Trichopus zeylanicus Gaertn. Arogyappacha Aqueous extract of whole plant DPPH and ABTS assays Tharakan et al., 2005
Withania coagulans Indian rennet Methanolic and aqueous extracts
of fruits
TBA assay Mathur et al., 2011
a
ABTS, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging; DPPH, 1,1-diphenyl-2-picrylhydrazine radical scavenging; FRAP, ferric reducing antioxidant power; FTC,
ferric thiocyanate; LPO, lipid peroxidation; TBA, thiobarbituric acid.

Plants of Indian Traditional Medicine 5
They include the following in vitro enzymatic
and non-enzymatic antioxidant assays:
• 1,1-diphenyl-2-picrylhydrazyl (DPPH, also
designated 2,2-diphenyl-1-picrylhydrazyl)
radical scavenging (Brand-
Williams et al.,
1995);
• β-carotene linoleic acid bleaching (Koleva
et al., 2002);
• inhibition of linoleic acid peroxidation
(Osawa and Namiki, 1981);
• ferric reducing antioxidant power (FRAP)
(Benzie and Strain, 1996);
• total radical trapping antioxidant poten-
tial (TRAP) (Krasowska et al., 2001);
• oxygen radical absorbance capacity
(ORAC) (Huang et al., 2002);
• 15-lipoxygenase inhibition (Lyckander
and Malterud, 1992);
• lipid peroxidation (LPO) (Ramos et al.,
2001);
• nitroblue tetrazolium (NBT) reduction or
superoxide anion scavenging activity
(Kirby and Schmidt, 1997);
• hydroxyl radical scavenging activity
(Jodynis-Liebert et al., 1999);
• non-site- and site-specific deoxyribose
degradation assay (Maulik et al., 1997);
• hydrogen peroxide scavenging activity
(Ruch et al., 1989);
• 2,2′-azino-bis(3-ethylbenzthiazoline-6-
sulfonic acid) (ABTS) radical scavenging
(Re et al., 1999);
• reducing power assay (Oyaizu, 1986);
• Briggs Rauscher (BR) method (Cervellati
et al., 2002);
• Trolox equivalent antioxidant capacity
(TEAC) method (Rice-Evans et al., 1996) –
Trolox (6-hydroxy-2,5,7,8-tetramethyl-
chroman-2-carboxylic acid) is a water-
soluble vitamin E analogue used as a
standard antioxidant;
• phenazine methosulfate–nicotinamide
adenine dinucleotide reduced (PMS–
NADH) system superoxide radical scav-
enging (Lau et al., 2002);
• linoleic acid peroxidation–ammonium
thiocyanate (ATC) method (Masuda et al.,
1992); and
• ferric thiocyanate (FTC) and thiobarbituric
acid (TBA) reaction methods (Mackeen
et al., 2000).
Of these methods, the most widely used and
reliable methods are the ABTS and DPPH
methods.
Auddy et al. (2003) screened the antioxi-
dant activity of the ethanolic extracts of three
Indian medicinal plants traditionally used for
the management of neurodegenerative dis-
eases, viz. Sida cordifolia, Evolvulus alsinoides
and Cynodon dactylon, and found IC50
(half
maximal inhibitory concentration) values
16.07, 33.39 and 78.62 mg/ml, respectively,
when tested with the ABTS assay. Using the
same assay, the relative antioxidant capacity
(IC50
) for water infusions of the same three
plants was as follows: E. alsinoides, 172.25 mg/ml;
C. dactylon, 273.64 mg/ml; and S. cordifolia
342.82 mg/ml. When tests were performed
of the effects of the water infusions on lipid
peroxidation, the IC50
values were as follows:
E. alsinoides 89.23 mg/ml; S. cordifolia, 126.78
mg/ml; and C. dactylon. 608.31 mg/ml.
Naik et al. (2003) examined the antioxi-
dant potential of four aqueous extracts from
different parts of medicinal plants used in
Ayurvedic medicine, viz. Momordica charantia,
Glycyrrhiza glabra, Acacia catechu and Termina-
lia chebula, using theABTS and DPPH methods.
The T. chebula extract showed the maximum
potency and was equivalent to that of ascorbic
acid. The IC50
value of the methanolic leaf
extract of Amaranthus viridis (14.25 μg/ml) was
greater than that of BHT (15.7 μg/ml) when
tested with the DPPH assay (Iqbal et al., 2012).
In a study by Reddy et al. (2005), three plant
foods, viz. dried amla (Indian gooseberry,

Emblica officinalis) fruits, dried drumstick
(
Moringa oleifera) leaves and raisins (from Vitis
vinifera) exhibited a high percentage of anti-
oxidant activity when evaluated using the
β-carotene–linoleic acid assay in an in vitro
system and compared with BHA.
Ali et al. (2008) reviewed 24 Indian

medicinal herbs reported to have antioxidant
properties. Gupta and Sharma (2006) pro-
vided a brief account of research reports on
common plants found in India, including
traditional medicinal plants with antioxidant
potential. Scartezzini and Speroni (2000) re-
viewed the antioxidant activity of Curcuma
longa, Mangifera indica, M. charantia, P. emblica,
Santalum album, Swertia chirata and Withania
somnifera, all of which are used in Indian

6 N.K. Dubey et al.
traditional medicine. Rathee et al. (2007)
found that the acetone-soluble fraction of the
ethyl acetate extract of Nyctanthes arbor-tristis
(harsingar) leaf had impressive antioxidant
activity as shown by the DPPH, hydroxyl and
superoxide radical and H2
O2
scavenging as-
says. Tanti et al. (2010) showed that the meth-
anolic leaf extract of Dendrocnide sinuata, a
medicinal plant used by the different tribal
communities of north-east India, exhibited high
free radical scavenging activity in the DPPH
assay at concentrations of 75 and 100 μg/ml.
1.3 Phytochemistry of Antioxidant Plants
Several studies have been carried out to iden-
tify antioxidant compounds that are pharma-
cologically potent and have a low profile of
side effects. The Ayurveda system provides
many leads for finding active and therapeut-
ically useful compounds from plants. Poly-
herbal preparations in Indian traditional
medicine may have antioxidant activity aris-
ing from their constituent plants, and these
may act synergistically to prevent ageing and
related degenerative diseases. Several Indian
medicinal plants have been extensively used
in the Ayurveda system as rejuvenators, slow-
ing the process of ageing and related disorders.
Plants and plant products are also part of the
vegetarian diet and may exhibit their medi-
cinal properties in this way. Moreover, the ac-
tive principles have been isolated from a large
number of medicinal plants; examples include
mangiferin from M. indica (Ghosal, 1996), the
tannins emblicanin A and B from P. emblica
(Ghosal et al., 1996) and curcumin from C. longa
(Ammon and Wahl, 1991).
The antioxidant activity of medicinal
plants may be attributed to the presence of
various phytochemicals (often secondary me-
tabolites) that have been identified. Natural
plant antioxidants are mainly in the form
of phenolic compounds (flavonoids, phen-
olic acids and alcohols, stilbenes, tocopherols,

tocotrienols), ascorbic acid and carotenoids. Of
these, the flavonoids, tannins and plant phe-
nolics are the major group of compounds that
act as primary antioxidants or free radical
scavengers. Furthermore, some of these nat-
ural phenolic compounds are more efficacious
as antioxidants than synthetic antioxidants
(Rice-Evans, 1996). Terpenoids (which include
the carotenoids) can both act as regulators of
metabolism and physiology and play a pro-
tective role as antioxidants (Graßmann, 2005).
The antioxidant properties of plants then may
well be a strong contributing factor to the use
of plants in the management and treatment of
various diseases and to their use in traditional
medicine (Scartezzini and Speroni, 2000).
Within the plants themselves, these same anti-
oxidants are important in protecting cells from
damage caused by free radicals and in offering
protection against cellular oxidation reactions.
Mathur et al. (2011) screened the phyto-
chemical constituents and the antioxidant
properties of methanolic and aqueous extracts
of the fruits of W. coagulans, which is one of
the most commonly used plants among trad-
itional practitioners. The phytochemical screen-
ing showed the presence of alkaloids, steroids,
phenolic compounds, tannins, saponins, carbo-
hydrates, proteins, amino acids and organic
acids. Both the methanolic and aqueous ex-
tracts showed high in vitro antioxidant activ-
ity compared with standard ascorbic acid,
although the aqueous extracts showed higher
antioxidant potential.
Leaf extracts of N. arbor-tristis are also ex-
tensively used in Indian traditional medicine.
The acetone-soluble fraction of the ethyl acet-
ate extract showed impressive antioxidant ac-
tivity in several in vitro experiments, e.g. the
DPPH, hydroxyl and superoxide radical and
H2
O2
scavenging assays. It also exhibited pre-
ventive activity against the Fe(II)-induced
lipid peroxidation of liposomes and γ-ray-
induced DNA damage. The strong reducing
power and high phenolic and flavonoid con-
tents could be responsible for the antioxidant
activity that was found(Rathee et al., 2007).
Tanti et al. (2010) suggested that the pres-
ence of terpenoids, tannins and flavonoids
could be responsible for antioxidant activity
of methanolic leaf extracts of D. sinuata.

Kumaran and Karunakaran (2007) found a
correlation between the antioxidant activity
and total phenolic content of five Phyllanthus
species from India; the species with a greater
phenolic content showed more antioxidant
activity and vice versa. Iqbal et al. (2012)
showed that the methanolic extract of leaves

of A. viridis had a higher phenolic content
(5.4–6%) and greater antioxidant activity than
the methanolic extract of the seeds, which
contained 2.4–3.7% phenolics, i.e. phenolic
content seems to be correlated with antioxi-
dant activity. Katalinic et al. (2006) screened
70 medicinal plant extracts for antioxidant
capacity (measured by the FRAP assay) and
total phenolic content and found a significant
linear correlation between the two.
As already noted, the antioxidant activ-
ity of these traditional medicinal plants may
come in part from antioxidant vitamins,

phenolics or tannins. Phenolics, in particular
flavonoids, are often directly linked to anti-
oxidant activity (Abu-Amsha et al., 1996;
Rice-Evans, 1996; Dreosti, 2000) and tannins,
which are astringent antioxidants, are known
to occur in Abies, Picea, Tsuga, Thuja, Juniperus,
Nuphar, Quercus, Populus, Gaultheria, Dirca,
Rhus, Prunus, Sorbus and Smilacina (Arnason
et al., 1981). Flavonoids are recognized to
have beneficial effects on plants protecting
them against ultraviolet light and even herbi-
vores (Harborne and Williams, 2000). Using a
variety of experimental model systems, it has
been found that the protective effects of fla-
vonoids are due to their capacity to transfer
electrons to free radicals and to chelate metal
catalysts (Ferrali et al., 1997), activate antioxi-
dant enzymes (Elliot et al., 1992), reduce α-
tocopherol radicals (Hancock et al., 2001) and
inhibit known free radical producing en-
zymes, such as myeloperoxidase and NADPH
oxidase (Middleton and Kandaswami, 1992)
and xanthine oxidase (Nagao et al., 1999). Fla-
vonoids have also been demonstrated to have
exceptional cardioprotective effects, essen-
tially because of their capacity to inhibit LDL
peroxidation (Mazur et al., 1999).
Tannins, which are astringent antioxi-
dants, are a prominent component of some of
plants (Arnason et al., 1981; Haslam, 1996),
and are known to occur in Abies, Picea, Tsuga,
Thuja, Juniperus, Nuphar, Quercus, Populus,
Gaultheria, Dirca, Rhus, Prunus, Sorbus and
Smilacina, which are traditionally used as
food, beverage and medicinal plants in east-
ern Canada (Arnason et al., 1981). Along with
anthocyanins, tannins could be contributory
factors in the antioxidant activities of medi-
cinal plants. In addition, tannins could have a
combined or synergistic effect with other
antioxidants (particularly ascorbic acid) within
the plant extract (Saucier and Waterhouse,
1999).
Tea contains tannin, with most of its
antioxidant activity attributed to catechins
(flavanol derivatives, also known as con-
densed tannins) (Nanjo et al., 1996). Rather
than containing a single chemical, however,
tea contains many different flavonoids, viz.
catechins, theaflavins and flavonols (Wiseman
et al., 1997), which together can lead to en-
hanced antioxidant activity. Both green tea
(Matsumoto et al., 1993) and black tea (Gomes
et al., 1995) have shown antidiabetic activity
in the reduction of blood glucose. Black tea
has lower antioxidant activity than green tea,
probably as a result of a factor of the fermen-
tation process that reduces its catechin con-
tent to 9% in contrast to green tea’s 30%
(Wiseman et al., 1997).
Coriandrum sativum (coriander) is an an-
nual herb that originates from the Mediterra-
nean region and is now extensively cultivated
in India. The seeds are aromatic, bitter and
have anti-inflammatory and diuretic proper-
ties. The herb helps in digestion and is useful
in treating burning sensations, coughs, bron-
chitis, vomiting, dyspepsia, diarrhoea, dysen-
tery, gout, rheumatism, intermittent fever
and giddiness (Varier, 1994). Coriander seeds
have been shown to have anti-peroxidative
properties (Chitra and Leelamma, 1999). The
activity of polyphenolic compounds from cori-
ander seeds in protecting against oxidative
damage induced by H2
O2
in human lympho-
cytes has been reported by Hashim et al.
(2005).Thecompoundsquercetin3-glucuronide,
isoquercitrin and rutin identified in corian-
der fruits (Kunzemann and Herrmann, 1977)
have also been reported to have antioxi-
dant properties as measured by the DPPH
assay (Wangensteen et al., 2004; Wong and
Kitts, 2006).
Furthermore, various complications of
diabetes, including retinopathy and athero-
sclerotic vascular diseases (the leading cause
of mortality in diabetics) have been linked to
oxidative stress (Baynes, 1991). Antioxidants
(vitamin E or C) have been used for treat-
ments of these diseases (Cunningham, 1998).
Different plants often contain substantial

8 N.K. Dubey et al.
amounts of tocopherols (vitamin E), caroten-
oids, ascorbic acid (vitamin C), flavonoids and
tannins, which are beneficial as antioxidants
for treatment of these diseases. Vitamin C is
an important dietary antioxidant (Rock et al.,
1996), and vitamin E is another dietary anti-
oxidant that has been investigated for its ef-
fect on diabetes (Paolisso et al., 1993; Cotter
et al., 1995). The combined antioxidant activ-
ity of these two dietary antioxidants vitamin E
and C is greater than their individual activ-
ities (Cotter et al., 1995), so it has been sug-
gested that this type of interaction may be an
important property of plant medicines asso-
ciated with diabetes (
Cunningham, 1998).
Many studies have been performed to
identify antioxidant compounds with phar
macological activity and a limited toxicity.
In this context, ethnopharmacology repre-
sents the most important way possible of
finding interesting and therapeutically help-
ful molecules.
1.4 Reverse Pharmacology with
Traditionally used Antioxidant
Plants
Reverse pharmacology is defined as the
science of integrating documented clinical

experiences and experiential observations
into leads by trans-disciplinary exploratory
studies and further developing these into
drug candidates or formulations through
robust preclinical and clinical research.
The traditional knowledge-inspired reverse
pharmacology described here relates to

reversing the routine ‘laboratory to clinic’
progress of discovery pipeline to change it
to ‘clinics to laboratories’. This means that
traditional medicine all over the world is
now being re-
evaluated by extensive re-
search on different plant species and their
therapeutic principles. The hidden potential
of many medicinal plants is yet to be dis-
covered as they were formerly intended
only for traditional use. A salient feature of
reverse pharmacology is the combination of
knowledge from traditional or folk medi-
cine with modern technologies to provide
better and safer leads.
An example is given by studies that have
been conducted on Trichopus zeylanicus (arog-
yappacha), a wild plant from a rare genus
that grows in the hilly Agasthyar forests of
Kerala. The tribal inhabitants (Kani tribe) of
this area use the plant as a health tonic and
rejuvenator (Sharma et al., 1989; Evans et al.,
2002). Singh et al. (2005) have explored and
identified the constituent(s) of the plant that
is(are) active in increasing the non-specific re-
sistance of the body to combat the harmful
influence of stress. The antioxidant properties
of T. zeylanicus were established using the free
radical assays DPPH and ABTS, and by meas-
uring its ability to reduce iron, lipoxygenase
activity and hydrogen peroxide-induced lipid
peroxidation. In another study, Tharakan
et al. (2005) demonstrated that T. zeylanicus
contains polyphenols and sulfhydryl com-
pounds that have the ability to scavenge ROS.
Although in vitro antioxidant assays
have been carried out on many plants with

reported medicinal properties, in vivo tests

remain to be done on the majority of them,
and the clinical efficacies of many plant pre-
parations that are in use have not yet been
validated. In addition, while the mechanism
of action of some of the antioxidants that have
been identified in plants is known, the active
ingredients in many plant extracts with anti-
oxidant properties remain to be identified.
A further elucidation of both known and yet
to be identified natural antioxidants in con-
cert with the newly emerging technology of
metabolomics could help disease prevention
and provide information on cures associated
with the use of simple herbs.
Herbs such as Amaranthus paniculatus,
Aerva lanata, Coccinia indica and C. sativum are
used as vegetables and could be a source of diet-
ary antioxidant supplies. Data on the phyto-
chemistry of these medicinal plants could
provide promising molecules for pharma-
cotherapy. As well as using such reverse
pharmacological studies on traditional medi-
cinal plants to provide an economic and time-
saving approach to drug development,
reverse pharmacology can also be applied for
determination of the hidden therapeutic

potential of traditional medicinal plants for
new indications. Here, it would be cheaper
and perhaps more productive to re-examine

plant remedies described in ancient texts. In
addition, it should be borne in mind that the
active antioxidant principles of medicinal
plants may be distributed in specific plant
parts, and may be affected by seasonal vari-
ation, geographical factors, other environ-
mental factors and plant age. Hence, such
factors should be considered during reverse
pharmacological studies on antioxidant plants.
Another consideration is the proper stand-
ardization of postharvesting processing of
raw materials from antioxidant plants.
1.5 Bioprospecting for Traditionally
Antioxidant Plants
Although modern medicine may be available
in countries like India, the traditional systems
of medicine are often used for various his-
torical, cultural and ecological reasons (Kun-
war et al., 2010). Quantitative intracultural
and intercultural comparisons of medicinal
plant knowledge analyses are believed to be
a valid ethnobotanical research approach

towards uncovering generalized knowledge
(Vandebroek, 2010).
Furthermore, each nation has rights
over its biodiversity, in spite of which a situ-
ation called biopiracy (or gene robbing) has
developed in which the genetic resources of

biodiversity-rich developing countries are
being exploited by biotechnologically rich
developed countries. C. longa and W. somnifera
are examples of antioxidant plants from India
that have been patented by outsiders on the
basis of secondary research. In such cases,
indigenous knowledge is being exploited for
commercial gain, with no compensation to the
indigenous peoples themselves. Many believe
that biopiracy contributes to the inequality
between the developing countries that are
rich in biodiversity and the developed coun-
tries that host the companies engaging in bio-
piracy.
This situation has given rise to the pro-
cess of bioprospecting, which deals with the
issues related to the protection of the legal
status of indigenous knowledge and compen-
sation to indigenous herbal practitioners for
that knowledge. Bioprospecting is an urgent
issue for a biodiversity-rich nation like India,
which needs to identify its useful plants, their
phytochemicals and the genes controlling
them, and to document these bio-resources.
Such an approach to India’s traditionally
used medicinal plants would no doubt be
helpful in a manyfold enhancement of Indian
herbal medicines in the global herbal market.
1.6 Conclusion
India is a rich home to rare medicinal plants
of high medicinal importance with antioxi-
dant activity. Several studies are ongoing
throughout the world to identify antioxidant
compounds that are pharmacologically po-
tent with a low profile of side effects, andAyur-
veda, the oldest medical system in the world,
provides many leads to finding active and
therapeutically useful compounds from plants.
Recent research has centred on various strat-
egies to protect crucial tissues and organs
against oxidative damage induced by free
radicals, and many novel approaches and sig-
nificant findings have been made in the last
few years.
The traditional Indian diet includes me-
dicinal plants that are rich sources of natural
antioxidants, and a higher intake of foods
with a high level of antioxidants could be a
strategy that is gaining in importance for pre-
venting diseases that are caused by the gener-
ation of free radicals. This antioxidant capacity
can be explored in the food industry by using
plants as a source of antioxidants to prevent
the development of rancidity and oxidation
in lipids. In fact, in recent years, research has
focused on the use of medicinal plants to ex-
tract natural and low-cost antioxidants that
are also safe and have nutritional and thera-
peutic value to replace synthetic additives
such as BHA and BHT that might be carcino-
genic and/or otherwise toxic. Such nutra-
ceuticals are likely to hold the key to a healthy
society in the future.
Further, many herbs that are used as
spices also have antimicrobial activity that is
of use in preventing the growth of food-borne
pathogens, while the herbal mixture prepar-
ations of Indian traditional medicine may

10 N.K. Dubey et al.
have an antioxidant activity arising from
their plant constituents that may well act in a
synergistic way. This hypothesis, along with
their lack of toxicity, is important for under-
standing both their past and present use.
Natural antioxidants mainly come from
plants in the form of phenolic compounds
(flavonoids, phenolic acids and alcohols,
stilbenes, tocopherols, tocotrienols), ascorbic
acid and carotenoids. The quest for such nat-
ural antioxidants, not only for their pharma-
ceutical uses, but also for dietary and
cosmetic uses, has become a major industrial
and scientific research challenge over the
last two decades. Efforts to gain extensive
knowledge on the power of plant antioxi-
dants and to tap their potential are therefore
on the increase.
References
Abu-Amsha, R., Croft, K.D., Puddey, I.B., Proudfoot, J.M. and Beilin, L.J. (1996) Phenolic content of various
beverages determines the extent of inhibition of human serum and low-density lipoprotein oxidation
in vitro: identification and mechanism of action of some cinnamic acid derivatives from red wine.
Clinical Science 91, 449–458.
Ajila, C.M., Naidu, K.A., Bhat, U.J.S. and Rao, P. (2007) Bioactive compounds and antioxidant potential of
mango peel extract. Food Chemistry 105, 982–988.
Ali, S.S., Kasoju, N., Luthra, A., Singh, A., Sharanabasava, H., Sahu, A. and Bora, U. (2008) Indian medicinal
herbs as sources of antioxidants. Food Research International 41, 1–15.
Amin, I.Y., Norazaidah, K.I. and Hainida, E. (2006) Antioxidant activity and phenolic content of raw and
blanched Amaranthus species. Food Chemistry 94, 47–52.
Ammon, H.P.T. and Wahl, M.A. (1991) Pharmacology of Curcuma longa. Planta Medica 57, 1–7.
Ao, C., Li, A., Elzaawely, A.A., Xuan, T.D. and Tawata, S. (2008) Evaluation of antioxidant and antibacterial
activities of Ficus microcarpa L. fil. extract. Food Control 19, 940–948.
Arnason, T., Hebda, R.J. and Johns, T. (1981) Use of plants for food and medicine by native peoples of eastern
Canada. Canadian Journal of Botany 59, 2189–2325.
Asha, V.V., Akhila, S., Wills, P.J. and Subramoniam, A. (2004) Further studies on the antihepatotoxic activity of
Phyllanthus maderaspatensis Linn. Journal of Ethnopharmacology 92, 67–70.
Auddy, B., Ferreira, M., Blasina, F., Lafon, L., Arredondo, F., Dajas, F., Tripathi, P.C., Seal, T. and Mukherjee, B.
(2003) Screening of antioxidant activity of three Indian medicinal plants, traditionally used for the man-
agement of neurodegenerative diseases. Journal of Ethnopharmacology 84, 131–138.
Badami, S., Gupta, M.K. and Suresh, B. (2003) Antioxidant activity of the ethanolic extract of Striga oroban-
chioides. Journal of Ethnopharmacology 85, 227–230.
Badami, S., Rai, S.R. and Suresh, B. (2005) Antioxidant activity of Aporosa lindleyana root. Journal of Ethno-
pharmacology 101, 180–184.
Baratto, M.C., Tattini, M., Galardi, C., Pinelli, P., Romani, A., Visioli, F., Basosi, R. and Pogni, R. (2003)
Antioxidant activity of galloyl quinic derivatives isolated from P. lentiscus leaves. Free Radical Research
37, 405–412.
Baynes, J.W. (1991) Role of oxidative stress in development of complications in diabetes. Diabetes 40, 405–412.
Beal, M.F. (1995) Aging, energy, and oxidative stress in neurodegenerative diseases. Annals of Neurology 38,
357–366.
Benzie, I.F.F. and Strain, J.J. (1996) The ferric reducing ability of plasma (FRAP) as a measure of antioxidant
power: the FRAP assay. Analytical Biochemistry 239, 70–76.
Brand-Williams, W., Cuvelier, M.E. and Berset, C. (1995) Use of a free radical method to evaluate antioxidant
activity. Journal of Food Science and Technology 28, 25–30.
Cerutti, P.A. (1991) Oxidant stress and carcinogenesis. European Journal of Clinical Investigation 21, 1–11.
Cerutti, P.A. (1994) Oxy-radicals and cancer. The Lancet 344, 862–863.
Cervellati, R., Renzulli, C., Guerra, M.C. and Speroni, E. (2002) Evaluation of antioxidant activity of some
natural polyphenolic compounds using the Briggs–Rauscher reaction method. Journal of Agricultural
and Food Chemistry 50, 7504–7509.
Chatterjee, M., Sarkar, K. and Sil, P.C. (2006) Herbal (Phyllanthus niruri) protein isolate protects liver from
nimesulide induced oxidative stress. Pathophysiology 13, 95–102.

Chitra, V. and Leelamma, S. (1999) Coriandrum sativum changes the levels of lipid peroxides and activity of
antioxidant enzymes in experimental animals. Indian Journal of Biochemistry and Biophysics 36, 59–61.
Chopra, R.N., Nayar, S.L. and Chopra, R.N. (1956) Glossary of Indian Medicinal Plants. Council for Scientific
and Industrial Research, New Delhi.
Cotter, M.A., Love, A., Watt, M.J., Cameron, N.E. and Dines, K.C. (1995) Effects of natural free radical scav-
engers on peripheral nerve and neurovascular function in diabetic rats. Diabetologia 38, 1285–1294.
Cunningham, J.J. (1998) Micronutrients as nutriceutical interventions in diabetes mellitus. Journal of the
American College of Nutrition 17, 7–10.
Dasgupta, N. and De, B. (2007) Antioxidant activity of some leafy vegetables of India: a comparative study.
Food Chemistry 101, 471–474.
Di Matteo, V. and Esposito, E. (2003) Biochemical and therapeutic effects of antioxidants in the treatment of
Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. Current Drug Targets – CNS
and Neurological Disorders 2, 95–107.
Dreosti, E. (2000) Antioxidant polyphenols in tea, cocoa and wine. Nutrition 16, 7–8.
Elliott, A.J., Scheiber, S.A., Thomas, C. and Pardini, R.S. (1992) Inhibition of glutathione reductase by flavonoids.
Biochemical Pharmacology 44, 1603–1608.
Evans, D.A., Subramoniam, A., Rajasekharan, S. and Pushpangadan, P. (2002) Effect of Trichopus zeylanicus
leaf extract on the energy metabolism in mice during exercise and at rest. Indian Journal of Pharmacology
34, 32–37.
Ferrali, M., Signorini, C., Caciotti, B., Sugherini, L., Ciccoli, L., Giachetti, D. and Comporti, M. (1997) Protec-
tion against oxidative damage of erythrocyte membrane by the flavonoid quercetin and its relation to iron
chelating activity. FEBS Letters 416, 123–129.
Gerber, M., Boutron-Ruault, M.C., Hercberg, S., Riboli, E., Scalbert, A. and Siess, M.H. (2002) Food and
cancer:
state of the art about the protective effect of fruits and vegetables. Bulletin du Cancer 89, 293–312.
Ghosal, S. (1996) A plausible chemical mechanism of bioactivities of mangiferin. Indian Journal of Chemistry
35B, 561–566.
Ghosal, S., Tripathi, V.K. and Chauhan, S. (1996) Active constituents of Emblica officinalis : Part 1. The chemistry
and antioxidative effects of two hydrolysable tannins, emblicanin A and B. Indian Journal of Chemistry
35B, 941–948.
Glaser, J.L. (1988) Maharishi Ayurveda: an introduction to recent research. Modern Science and Vedic Science
2, 88–108.
Gomes, A., Vedasiromoni, J.R., Das, M., Sharma, R.M. and Ganguly, D.K. (1995) Anti-hyperglycemic effect of
black tea (Camellia sinensis) in rat. Journal of Ethnopharmacology 45, 223–226.
Govindarajan, R., Rastogi, S.,Vijayakumar, M., Shirwaikar, A., Rawat, A.K.S, Mehrotra, S. and Pushpangadan, P.
(2003) Studies on the antioxidant activities of Desmodium gangeticum. Biological and Pharmaceutical
Bulletin 26, 1424–1427.
Graßmann, J. (2005) Terpenoids as plant antioxidants. Vitamins and Hormones 72, 505–535.
Gupta, V.K. and Sharma, S.K. (2006) Plants as natural antioxidants. Indian Journal of Natural Products and
Resources 5, 326–334.
Halliwell, B. (1997) Antioxidants and human diseases: a general introduction. Nutrition Reviews 55, S44–S52.
Halliwell, B. and Gutteridge, J.M.C. (1999) Free Radicals in Biology and Medicine, 3rd edn. Oxford University
Press, Oxford, UK.
Hancock, J., Desikan, R. and Neill, S. (2001) Role of reactive oxygen species in cell signaling pathways.
Biochemical Society Transactions 29, 345–350.
Harborne, J.B. and Williams, C.A. (2000) Advances in flavonoid research since 1992. Phytochemistry 55,
481–504.
Hashim, M.S., Lincy, S., Remya, V., Teena, M. and Anila, L. (2005) Effect of polyphenolic compounds from
Coriandrum sativum on H2
O2
-induced oxidative stress in human lymphocytes. Food Chemistry 92, 653–660.
Haslam, E. (1996) Natural polyphenols (vegetable tannins) as drugs: possible modes of action. Journal of Natural
Products 59, 205–215.
Huang, D., Ou, B., Hampsch-Woodill, M.F., Judith, A. and Prior, R.L. (2002) High-throughput assay of oxygen
radical absorbance capacity (ORAC) using a multichannel liquid handling system coupled with a mi-
croplate fluorescence reader in 96-well format. Journal of Agricultural and Food Chemistry 50, 4437–4444.
Iqbal, M.J., Hanif, S., Mahmood, Z., Anwar, F. and Jamil, A. (2012) Antioxidant and antimicrobial activities of
chowlai (Amaranthus viridis L.) leaf and seed extracts. Journal of Medicinal Plants Research 6, 4450–4455.
Ito, N., Fukushima, S., Hassegawa, A., Shibata, M. and Ogiso, T. (1983). Carcinogenicity of butylated

hydroxyanisole in F344 rats. Journal of the National Cancer Institute 70, 343–347.

Jodynis-Liebert, J., Murias, M. and Bolszyk, E. (1999) Effect of several sesquiterpene lactones on lipid peroxi-
dation and glutathione level. Planta Medica 65, 320–324.
Katalinic, V., Milos, M., Kulisic, T. and Jukic, M. (2006) Screening of 70 medicinal plant extracts for antioxi-
dant capacity and total phenols. Food Chemistry 94, 550–557.
Kilani, S., Abdelwahed, A., Chraief, I., Ammar, R.B., Hayder, N., Hammami, M., Ghedira, K. and Chekir-
Ghedira, L. (2005) Chemical composition, antibacterial and antimutagenic activities of essential oil from
(Tunisian) Cyperus rotundus. Journal of Essential Oil Research 17, 695–700.
Kirby, A.J. and Schmidt, R.J. (1997) The antioxidant activity of Chinese herbs for eczema and of placebo herbs.
Journal of Ethnopharmacology 56, 103–108.
Knekt, P., Jarvinen, R., Reunanen, A. and Maatela, J. (1996) Flavonoid intake and coronary mortality in

Finland: a cohort study. BMJ 312, 478–481.
Koleva, I.I., van Beek, T.A., Linssen, J.P.H., de Groot, A. and Evstatieva, L.N. (2002) Screening of plant ex-
tracts for antioxidant activity: a comparative study on three testing methods. Phytochemical Analysis
13, 8–17.
Krasowska, A., Rosiak, D., Szkapiak, K., Oswiecimska, M., Witek, S. and Lukaszewicz, M. (2001) The antioxi-
dant activity of BHT and new phenolic compounds PYA and PPA measured by chemiluminescence.
Cellular and Molecular Biology Letters 6, 71–81.
Krishnaiah, D., Sarbatly, R. and Nithyanandam, R. (2011) A review of the antioxidant potential of medicinal
plant species. Food and Bioproducts Processing 89, 217–233.
Kubola, J. and Siriamornpun, S. (2008) Phenolic contents and antioxidant activities of bitter gourd (Momordica
charantia L.) leaf, stem and fruit fraction extracts in vitro. Food Chemistry 110, 881–890.
Kumaran, A. and Karunakaran, R.J. (2007) In vitro antioxidant activities of methanol extracts of five Phyllanthus
species from India. LWT – Food Science and Technology 40, 344–352.
Kunwar, R.M., Shrestha, K.P. and Bussmann, R.W. (2010) Traditional herbal medicine in far-west Nepal:
a pharmacological appraisal. Journal of Ethnobiology and Ethnomedicine 6(35), 1–18.
Kunzemann, J. and Herrmann, K. (1977) Isolation and identification of flavon(ol)-O-glycosides in caraway
(Carum carvi L.), fennel (Foeniculum vulgare Mill.), anise (Pimpinella anisum L.), and coriander (Corian-
drum sativum L.), and of flavon-C-glycosides in anise. I. Phenolics of spices. Zeitschrift für Lebensmittel-
Untersuchung und -Forschung A 164, 194–200.
Lau, K.M., He, Z.D., Dong, H., Fung, K.P. and But, P.P.H. (2002) Antioxidative, anti-inflammatory and hepato-
protective effects of Ligustrum robustum. Journal of Ethnopharmacology 83, 63–71.
Lyckander, I.M. and Malterud, K.E. (1992) Lipophilic flavonoids from Orthosiphon spicatus as inhibitors of
15-lipoxygenase. Acta Pharmaceutica Nordica 4, 159–166.
Mackeen, M.M., Ali, A.M., Lajis, N.H., Kawazu, K., Hassan, Z., Amran, M., Habsah, M., Mooi, L.Y. and

Mohamed, S.M. (2000) Antimicrobial, antioxidant, antitumour-promoting and cytotoxic activities of
different plant part extracts of Garcinia atroviridis Griff. ex. T. Anders. Journal of Ethnopharmacology 72,
395–402.
Masuda, T., Isobe, J., Jitoe, A. and Nakatani, N. (1992) Antioxidant curcuminoids from rhizomes of Curcuma
zanthorrhiza. Phytochemistry 31, 3645–3647.
Mathur, D., Agrawal, R.C. and Shrivastava, V. (2011) Phytochemical screening and determination of antioxi-
dant potential of fruits extracts of Withania coagulans. Recent Research in Science and Technology 3(11),
26–29.
Matsumoto, N., Ishigaki, F., Ishigaki, A., Iwashina, H. and Hara, Y. (1993) Reduction of blood glucose levels
by tea catechin. Bioscience, Biotechnology and Biochemistry 57, 525–527.
Maulik, G., Maulik, N., Bhandarp, V., Kagan, V., Pakrashi, S. and Das, D.K. (1997) Evaluation of antioxidant
effectiveness of a few herbal plants. Free Radical Research 27, 221–228.
Mazur, A., Bayle, D., Lab, C., Rock, E. and Rayssiguier, Y. (1999) Inhibitory effect of procyanidin-rich extracts
on LDL oxidation in vitro. Atherosclerosis 145, 421–422.
Middleton, E. and Kandaswami, C. (1992) Effects of flavonoids on immune and inflammatory cell functions.
Biochemistry and Pharmacology 43, 1167–1179.
Nagao, A., Seki, M. and Kobayashi, H. (1999) Inhibition of xanthine oxidase by flavonoids. Bioscience, Bio-
technology and Biochemistry 63, 1787–1790.
Naik, G.H., Priyadarsini, K.I., Satav, J.G., Banavalikar, M.M., Sohoni, D.P., Biyani, M.K. and Mohan, H. (2003)
Comparative antioxidant activity of individual herbal components used in Ayurvedic medicine. Phyto-
chemistry 63, 97–104.
Nanjo, F., Goto, K., Suzuki, M., Sakai, M. and Hara, Y. (1996) Scavenging effects of tea catechins and their
derivatives on 1,1-diphenyl-2-picrylhydrazyl radical. Free Radicals in Biology and Medicine 21, 895–902.

Natarajan, K.S., Narasimhan, M., Shanmugasundaram, K.R. and Shanmugasundaram, E.R.B. (2006) Antioxi-
dant activity of a salt–spice–herbal mixture against free radical induction. Journal of Ethnopharmacology
105, 76–83.
Osawa, T. and Namiki, M. (1981) A novel type of antioxidant isolated from leaf wax of Eucalyptus leaves.
Agricultural and Biological Chemistry 45, 735–739.
Oyaizu, M. (1986) Studies on products of browning reaction prepared from glucosamine. Japanese Journal of
Nutrition 44, 307–315.
Paolisso, G., D’Amore, A., Giugliano, D., Ceriello, A.,Varricchio, M. and D’Onofrio, F. (1993) Pharmacologic
doses of vitamin E improve insulin action in healthy subjects and non-insulin-dependent diabetic
patients. The American Journal of Clinical Nutrition 57, 650–656.
Patel, V.R., Patel, P.R. and Kajal, S.S. (2010) Antioxidant activity of some selected medicinal plants in western
region of India. Advances in Biological Research 4, 23–26.
Pietta, P.G. (2000) Flavonoids as antioxidants. Journal of Natural Products 63, 1035–1042.
Prince, P.S.M. and Menon, V.P. (1999) Antioxidant activity of Tinospora cordifolia roots in experimental dia-
betes. Journal of Ethnopharmacology 65, 277–281.
Ramos, A., Rivero, R., Victoria, M.C., Visozo, A., Piloto, J. and Garcia, A. (2001) Assessment of mutagenicity
in Parthenium hysterophorus L. Journal of Ethnopharmacology 77, 25–30.
Rathee, J.S., Hassarajani, S.A. and Chattopadhyay, S. (2007) Antioxidant activity of Nyctanthes arbor-tristis leaf
extract. Food Chemistry 103, 1350–1357.
Ravikumar, Y.S., Mahadevan, K.M., Kumaraswmay, M.N., Vaidya, V.P., Manjunatha, H., Kumar, V. and

Satyanarayana, N.D. (2008) Antioxidant cytotoxic and genotoxic evaluation of alcoholic extract of Poly-
althia cerasoides (Roxb.) Bedd. Environmental Toxicology and Pharmacology 26, 142–146.
Re, R., Pelligrini, N., Proteggente, A., Pannala, A., Yang, M. and Rice-Evans, C.A. (1999) Antioxidant activity
applying an improved ABTS radical cation decolorization assay. Free Radical Biology and Medicine 26,
1231–1237.
Reddy, V., Urooj, A. and Kumar, A. (2005) Evaluation of antioxidant activity of some plant extracts and their
application in biscuits. Food Chemistry 90, 317–321.
Rice-Evans, C., Miller, N.J. and Paganga, G. (1996) Structure–antioxidant activity relationship of flavonoids
and phenolic acids. Free Radical Biology and Medicine 20, 933–956.
Rock, C.L., Jacob, R.A. and Bowen, P.E. (1996) Update on the biological characteristics of the antioxidant
micronutrients: vitamin C, vitamin E, and the carotenoids. Journal of the American Dietetic Association
96, 693–702.
Ruch, R.J., Cheng, S.J. and Klaunig, J.E. (1989) Prevention of cytotoxicity and inhibition of intercellular com-
munication by antioxidant catechins isolated from Chinese green tea. Carcinogenesis 10, 1003–1008.
Saucier, C.T. and Waterhouse, A.L. (1999) Synergetic activity of catechin and other antioxidants. Journal of
Agricultural and Food Chemistry 47, 4491–4494.
Scartezzini, P. and Speroni, E. (2000) Review of some plants of Indian traditional medicine with antioxidant
activity. Journal of Ethnopharmacology 71, 23–43.
Seethalaxmi, M.S., Shubharani, R., Nagananda, G.S. and Sivaram, V. (2012) Phytochemical analysis and free
radical scavenging potential of Baliospermum montanum (Willd.) Muell. leaf. Asian Journal of Pharma-
ceutical and Clinical Research 5, 135–137.
Shahidi, F., Janitha, P.K. and Wanasundara, P.D. (1992) Phenolic antioxidants. Critical Reviews in Food Sci-
ence and Nutrition 32, 67–103.
Shanmugasundaram, P. and Venkataraman, S. (2006) Hepatoprotective and antioxidant effects of Hygrophila
auriculata (K. Schum) Heine Acanthaceae root extract. Journal of Ethnopharmacology 104, 124–128.
Sharma, A.K., Pushpangadan, P., Chopra, C.L., Rajasekharan, S. and Saradamma, L. (1989) Adaptogenic ac-
tivity of seeds of Trichopus zeylanicus Gaertn., the Ginseng of Kerala. Ancient Science of Life 8, 212–219.
Shirwaikar, A., Issac, D. and Malini, S. (2004). Effect of Aerva lanata on cisplatin and gentamicin models of
acute renal failure. Journal of Ethnopharmacology 90, 81–86.
Siems, W.G., Grune, T. and Esterbauer, H. (1995) 4-Hydroxynonenal formation during ischemia and reperfu-
sion of rat small intestine. Life Sciences 57, 785–789.
Sies, H. (1993) Strategies of antioxidant defense. European Journal of Biochemistry 215, 213–219.
Singh, B., Chandan, B.K., Sharma, N., Singh, S., Khajuria, A. and Gupta, D.K. (2005) Adaptogenic activity of
glyco-peptido-lipid fraction from the alcoholic extract of Trichopus zeylanicus Gaerten (part II). Phyto-
medicine 12, 468–481.
Sreejayan, N. and Rao, M. (1996) Free radical scavenging activity of curcuminoids. Drug Research 46, 169–171.
Stadtman, E.R. (2004) Role of oxidant species in aging. Current Medical Chemistry 11, 1105–1112.

Tanti, B., Buragohain, A.K., Gurung, L., Kakati, D., Das, A.K. and Borah, S.P. (2010) Assessment of antimicro-
bial and antioxidant activities of Dendrocnide sinuata (Blume) Chew leaves – a medicinal plant used by
ethnic communities of North East India. Indian Journal of Natural Products and Resources 1, 17–21.
Tharakan, B., Dhanasekaran, M. and Manyam, B.V. (2005) Antioxidant and DNA protecting properties of
anti-fatigue herb Trichopus zeylanicus. Phytotherapy Research 19, 669–673.
Vandebroek, I. (2010) The dual intracultural and intercultural relationship between medicinal plant know-
ledge and consensus. Economic Botany 64, 303–317.
Varier,V.P.S. (1994) Indian Medicinal Plants:A Compendium of 500 Species,Vol. 2. Orient Longman, Madras, India.
Wangensteen, H., Samuelsen, A.B. and Malterud, K.E. (2004) Antioxidant activity in extracts from coriander.
Food Chemistry 88, 293–297.
Winston, J.C. (1999) Health-promoting properties of common herbs. American Journal of Clinical Nutrition
70, 491–499.
Wiseman, S.A., Balentine, D.A. and Frei, B. (1997) Antioxidants in tea. Critical Reviews in Food Science and
Nutrition 37, 705–718.
Wong, P.Y.Y. and Kitts, D.D. (2006) Studies on the dual antioxidant and antibacterial properties of parsley
(Petroselinum crispum) and cilantro (Coriandrum sativum) extracts. Food Chemistry 97, 505–515.
Zaman, H. (1974) The South-east Asia region. In: Bannerman, R.H. (ed.) Traditional Medicine. World Health
Organization, Geneva, Switzerland, pp. 231–239.

© CAB International 2015. Plants as a Source of Natural Antioxidants (ed. N.K. Dubey) 15
2.1 Introduction
The oxidative damages caused by reactive
oxygen species (ROS) to lipids, proteins and
nucleic acids may trigger various chronic
diseases, such as coronary heart disease, can-
cer, ageing, diabetes, asthma and rhinitis
(Dhalla et al., 2000; Eberhardt et al., 2000;
Bowler and Crapo, 2002; Hussain et al., 2003;
Maritim et al., 2003; Neumann et al., 2003).
Epidemiological studies have established an
inverse correlation between the intake of
vegetables and fruits and mortality from
age-related diseases such as atherosclerosis,
cancer and diabetes, which could be partly
attributed to their natural antioxidant con-
tent (Gey, 1990; Stephens et al., 1996; Eber-
hardt et al., 2000; La Vecchia et al., 2001).
Natural antioxidants are also going to be of
importance in replacing the synthetic anti-
oxidants that have been widely used in the
food industry to prolong product shelf life,
because various studies have found that
these can be both toxic and carcinogenic. Ex-
amples are butylhydroxyanisole, or BHA
(see Ito et al., 1986) and butylhydroxytoluene,
or BHT (see Safer and Al-Nughamish, 1999).
It is, therefore, vital that new sources of safe and
inexpensive natural antioxidants are found.
Traditional Chinese medicinal plants
(TCMPs) have been used to treat human dis-
eases in China for thousands of years, and
people are becoming increasingly interested
in them because of their good health effects
and low toxicity. The health benefits of TC-
MPs are thought to arise partly from the ef-
fects of the antioxidants that they contain on
ROS produced in the human body. In recent
years, studies on the antioxidant activities
of TCMPs have increased remarkably in
light of the increased interest in their poten-
tial as a rich source of natural antioxidants
(Liu and Ng, 2000; Ou et al., 2003; Cai et al.,
2004; Li et al., 2008). Several studies have in-
dicated that
TCMPs possess more potent
antioxidant activities than common dietary
plants, and contain a wide variety of natural
antioxidants, such as phenolic acids, flavon-
oids and tannins (Dragland et al., 2003; Cai
et al., 2004).
This chapter reviews natural antioxidants
from TCMPs. Section 2.2 gives examples of
the plants that are used in the Chinese medical
system, with information on their antioxidant
2 Natural Antioxidants from Traditional
Chinese Medicinal Plants
Li Sha,1
Li Shu-Ke,1
Li Hua-Bin,1
* Xu Xiang-Rong,2
Li Fang,1
Wu Shan1
and Li An-Na1
1
Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School
of Public Health Sun Yat-Sen University, Guangzhou, China; 2
Key Laboratory
of Marine Bio-resources Sustainable Utilization, South China Sea Institute of
Oceanology, Chinese Academy of Sciences, Guangzhou, China
*Corresponding author. E-mail address: lihuabin@mail.sysu.edu.cn

16 Li Sha et al.
capacities and phenolic contents, and the
methods used to measure these. Section 2.3
presents details of the natural antioxidants
that have been identified in TCMPs, their
relative activities and the methods used for
their separation and identification. Conclu-
sions and future prospects are outlined in
Section 2.4.
2.2 Antioxidant Plants Used in the
Chinese System of Medicine
Evaluation of the antioxidant activities of TC-
MPs is very important because plants that
have high antioxidant capacities and could be
valuable sources of natural antioxidants can
then be screened out. Examination of the lit-
erature shows that the antioxidant activities
of many TCMPs have been evaluated, as ex-
emplified by the studies of Liu and Ng (2000);
Zheng and Wang (2001), Chen et al. (2004),
Yang et al. (2006), Chang et al. (2007) and Chan
et al. (2008). Special attention has been paid to
TCMPs that have blood circulatory regulat-
ing actions (Zhu et al., 2004; Liao et al., 2008),
heat-clearing functions (Long et al., 1999; Liao
et al., 2007), nutritional and tonic properties
(Leung et al., 2005; Liu et al., 2008), antiviral
activity (Chen et al., 2005) and anticancer ac-
tivity (Cai et al., 2004).
The classification of TCMPs designates a
group of them to the ‘pao’ category. These
TCMPs have good health benefits, generally a
lower toxicity and have been consumed as
health tonics or as anti-ageing remedies. The
antioxidant capacities and total phenolic con-
tents of these plants have been measured by
standard methods: the ferric reducing anti-
oxidant power (FRAP) and Trolox equivalent
antioxidant capacity (TEAC) assays, as well
as the Folin–Ciocalteu method (Li et al., 2007);
Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-
2- carboxylic acid) is a water-soluble vitamin
E analogue that is used as a standard antioxi-
dant. The antioxidant capacities of pao cat-
egory plants ranged from 2.9 to 696.7 μmol
Fe(II)/g in the FRAP assay and from 1.7 to
469.5 μmol Trolox/g in the TEAC assay; their
total phenolic contents were in the range of
2.07 to 51.83 mg gallic acid equivalents (GAE)/g.
Several pao plants – Rhodiola sacra, Polygonum
multiflorum, Dipsacus japonicus, Epimedium
brevicornum, Paeonia lactiflora, Ligustrum lu
cidum and Cynomorium songaricum were found
to possess high antioxidant capacities and
total phenolic contents, which are potentially
rich sources of natural antioxidants.
Liu et al. (2008) measured the polyphe-
nol contents and antioxidant capacities of
68 TCMPs suitable for medicinal and food uses
using the Folin–Ciocalteu, FRAP and DPPH
(2,2-diphenyl-1-picrylhydrazyl, also known as
1,1-diphenyl-2-picrylhydrazyl)radical-scavenging
assays (Liu et al., 2008). The plants (or plant
parts) that had high total phenolic (45 mg
GAE/g) and flavonoid (45 mg rutin equiva-
lents (RE)/g) contents also had the highest
antioxidantcapacities(FRAPvalue2.5mmol/g,
and DPPH radical-scavenging capacity 85%).
They included Chinese white olive [Canarium
album], clove [Syzygium aromaticum], prick-
lyash [Zanthoxylum] peel, villous amomum
fruit [from Amomum villosum], Chinese star
anise [Illicium verum] and pagoda tree [Styph
nolobium japonicum] flower which, therefore,
have potential as natural sources of antioxi-
dant foods.
Another group of plants, those categorized
in the ‘heat-clearing’ category, have
attracted
much attention in recent years because they
possess significant anti-inflammatory, anti-
allergic, anti-tumour, antiviral and antibac-
terial activities that could be partly attributed
to their antioxidant and free radical scavenging
activities (Schinella et al., 2002; Cai et al., 2004).
The antioxidant capacities and total phenolic
contents of 45 TCMPs within this category
were measured using the FRAP and TEAC as-
says, and the Folin–Ciocalteu method (Li et al.
2008). Several of them, including Sargentodoxa
cuneata, Fraxinus rhynchophylla, Paeonia lactiflora,
P. suffruticosa and Scutellaria baicalensis showed
high antioxidant capacities and total phenolic
contents, and so are potentially rich sources of
natural antioxidants, both for the preparation
of crude extracts and for the further isolation
and purification of antioxidant components.
A strong correlation between TEAC and
FRAP values implied that the antioxidants in
these plants were capable of scavenging free
radicals and reducing oxidants.
Glechoma hederacea has been used for the
treatment of diuresis and to stimulate the

Traditional Chinese Medicinal Plants 17
blood circulation. The antioxidant activities
of the hot water extract of this plant were
evaluated by different assays, and the results
showed that the extract had antioxidant ac-
tivities that were significantly higher than
those of vitamin C and Trolox in terms of
superoxide anion radical scavenging activity
and Fe2+
-chelating ability (Chou et al., 2012).
Puerariae radix (or Radix puerariae), which
is the dried root of kudzu (Pueraria lobata) is
used for the treatment of coronary heart dis-
ease, myocardial infarction and hypertension.
Three compounds from the crude extract of
this preparation – puerarin, daidzin and
daidzein – were screened and identified as hav-
ing strong antioxidant activity. Daidzein had
strong free radical scavenging activity and
metal chelating activity. Puerarin exhibited a
good DPPH free radical scavenging activity
although its metal chelating capacity was
relatively weak (Chen et al., 2011).
Song et al. (2010) evaluated the anti-
oxidant capacities of 56 selected Chinese

medicinal plants used for the prevention and
treatment of colds, flu and coughs. The re-
sults showed that Dioscorea bulbifera, Eriobot
rya japonica, Tussilago farfara and Ephedra sinica
could be potential rich sources of natural anti-
oxidants.
Panax japonicus has been extensively
used by people of the Tujia nationality in
China. Two polysaccharides named as CP-1a
and CP-2a were extracted and isolated from
rhizomes of the plant and their antioxidant
activities were evaluated by various systems,
including scavenging activities for super-
oxide anions and the hydroxyl and DPPH
radicals. Both samples had inhibitory effects
towards superoxide anions and hydroxyl
and DPPH radicals, with CP-1a showing
a stronger scavenging ability than CP-2a (Wang
et al., 2012a).
Taxillus sutchuenensis is a special folk

medicinal plant in Taiwan. The antioxidant
activities of an aqueous ethanol extract of
T. sutchuenensis various fractions of this were
evaluated by Liu et al. (2012). Among the

fractions assayed, the ethyl acetate fraction
showed the highest TEAC and DPPH radical
scavenging activities. This fraction had also
the highest polyphenol and flavonoid contents.
Quercetin might be an important bioactive
compound in this plant. The results indicated
that T. sutchuenensis is a potent antioxidant
medicinal plant and that its efficacy may be
mainly attributed to its polyphenol content.
Cordyceps jiangxiensis is a medicinal ento-
mopathogenic macrofungus native to east-
ern China. The antioxidant capabilities of
the polysaccharide fractions of the fungus were
evaluated by five assays: the scavenging abil-
ities for DPPH, hydroxyl and superoxide
anion radicals, reducing power and chelating
ability for ferrous ions. The polysaccharide
fractions presented excellent scavenging abil-
ities for superoxide anion radicals. The anti-
oxidantabilitiesofthedifferentpolysaccharide
fractions differed according to the dose tested
but all acted in a dose-dependent manner.
The results suggested that polysaccharides are
an important antioxidant component in the
medicinal activity of this fungus and that
it is also a promising potential source for the

development of natural antioxidants (Xiao
et al., 2011).
Gao et al. (2011) studied the antioxidant
activities of four water-soluble polysacchar-
ide fractions isolated from the tubers of Aco
nitum kusnezoffii. The results indicated that
fraction WKCP-A had noticeable scavenging
activities for DPPH and hydroxyl radicals,
superoxide anions and H2
O2
, was active in the
self-oxidation of 1,2,3-phentriol and showed
ferrous ion-chelating ability and reducing
power. The water-soluble polysaccharides from
A. kusnezoffii, especially WKCP-A, therefore
have the potential to be explored as novel nat-
ural antioxidants for use in functional foods
or medicine.
The antioxidant activities of Ixora chin
ensis were investigated by Chen et al. (2013)

using the DPPH and ABTS (2,2′-azino-bis
(3-ethylbenzthiazoline-6-sulfonic acid) rad-
ical scavenging assays and the reducing
power assay. The results showed that various
extracts of I. chinensis, especially an acetone
extract, had potent antioxidant activities,
which could be exploited in functional food
and medicinal materials.
Jeong et al. (2013) evaluated the antioxi-
dant activity of various solvent fractions of
Smilax china. The results showed that the
ethyl acetate fractions exhibited the highest
antioxidant activities, and that these also had

18 Li Sha et al.
the highest amount of total phenolics (401.62
mg/g). It is suggested that the high antioxi-
dant properties of the root of S. china might be
beneficial to the antioxidant protection system
of the human body against oxidative damage.
Jiang et al. (2012) examined the antioxi-
dant activity of the essential oil of Artemisia
scopariae (as the dried shoot preparation Herba
Artemisiae Scopariae) using preparation using
the DPPH radical scavenging and FRAP as-
says. The essential oil exhibited a strong anti-
oxidant activity, indicating a good potential
for use in the food and pharmaceutical industry.
In recent years, cancer prevention and
treatment using traditional Chinese medicines
has attracted increasing interest. The antioxi-
dant capacities and phenolic compounds of 112
TCMPs that have been associated with antican-
cer activity were evaluated by Cai et al. (2004).
The TEAC values of these plants were in the
rangeof46.7–17,323μmolTroloxequivalent/100g
dry weight (DW), and the total phenolic con-
tents in the range of 0.2–50.3 g GAE/100 g DW.
The major types of phenolic compounds in
these plants were also preliminarily identified,
and included phenolic acids, flavonoids, tan-
nins, coumarins, lignans, quinones, stilbenes
and curcuminoids. These plants showed far
stronger antioxidant capacities, and contained
significantly higher levels of phenolics, than
common vegetables and fruits, and could be
a potential source of natural antioxidants.
Liao et al. (2008) evaluated the antioxi-
dant capacities of 45 TCMPs that regulate
blood circulation using the oxygen radical ab-
sorbance capacity (ORAC) assay. This ex-
presses its results as Trolox equivalents (TE)
and gave a range of 40–1990 μmol TE/g plant.
Several plants with high antioxidant capacity
were screened out, and these included Spatho
lobus suberectus, Sanguisorba officinalis, Agrimonia
pilosa, Artemisia anomala, Salvia miltiorrhiza
and Nelembo nucifera.
The antioxidant activities of five antiviral
TCMPs (Ampelopsis sinica, A. humiliforlia, Po
tentilla freyniana, Selaginella labordei and Chrys
anthemum multiflorum) were studied by Chen
et al. (2005) using both enzymatic and non-
enzymatic in vitro antioxidant assays. All five
plants inhibited xanthine oxidase and lipoxy-
genase activities, and were scavengers of the
ABTS radical cation using the TEAC assay.
Gan et al. (2010a) investigated 40 medi-
cinal plants associated with the prevention
and treatment of cardiovascular and cerebro-
vascular diseases. Most of these plants were
being analysed for their antioxidant activities
for the first time. Generally, they had high
tents. Several plants (Sanguisorba officinalis,
Rosa chinensis, Millettia dielsiana, Polygonum
cuspidatum, Caesalpina sappan and Sophora
japonica) showed high antioxidant activities
and total phenolic contents. These could be
potential rich resources of natural antioxi-
dants, and could be developed into functional
foods or drugs for the prevention and treat-
ment of diseases caused by oxidative stress.
Gan et al. (2010b) also systemically evaluated
50 medicinal plants associated with treatment
of rheumatic diseases. The results suggested
that the antioxidant compounds in these
plants had both free radical scavenging activ-
ity and oxidant reducing power. The highest
tent were shown by Geranium wilfordii, Loran
thus parasiticus, Polygonum aviculare, Pyrrosia
sheaeri, Sinomenium acutum and Tripterygium
wilfordii, and these are therefore potentially
rich sources of natural antioxidants.
Studies by Su et al. (2011) confirmed that
the antioxidant capacities of plant extracts

depend to a certain extent on the kinds of
solvent used to make extracts. Various solvent
extracts of Phymatopteris hastate were screened,
and the results showed that the ethyl acetate
extract had outstanding antioxidant activity,
which was close or even superior to that of the
widely used synthetic antioxidant BHT. Fur-
thermore, the antioxidant activity and the
total phenolic and total flavonoid contents of
different extracts followed the same order:
ethyl acetate extract butyl alcohol extract
petroleum ether extract. All of the extracts, es-
pecially the ethyl acetate extract, were rich in
phenolics and flavonoids.
Deng et al. (2011) examined the antioxi-
dant activity of an ethanolic extract of Taxillus
liquidambaricola and demonstrated that this
had high TEAC and DPPH radical scaven-
ging activities as well as high contents of
polyphenols and flavonoids. When Peng et al.
(2011) evaluated the antioxidant activity of an
aqueous extract of Astragalus membranaceus,

it was shown to effectively scavenge super-
oxide anions, hydrogen peroxide (H2
O2
) and
DPPH radicals, and to decrease 2,2¢-azo-
bis(2-amidinopropane) hydrochloride (AAPH)-
induced human erythrocytes haemolysis. The
results indicated that the aqueous extract of
A. membranaceus has very potent antioxidant
activity. Wang et al. (2012b) studied the anti-
oxidant properties of both the aqueous and
ethanolic extracts of leaves, stems and fruits
of Morus alba. The ethanolic extracts showed
higher contents of both total phenolics and
flavonoids than the aqueous extracts, and the
antioxidant activity of the ethanolic extracts
was also stronger than that of the aqueous ex-
tracts, in the order: leaf extracts fruit extracts
stem extracts.
Investigations were carried out by Zhang
et al. (2011a) on the antioxidant activities of
aqueous and ethanolic extracts of 14 Chinese
medicinal plants and measured their total
phenolic and flavonoid contents. The antioxi-
dant activity was evaluated in a biological
assay using Saccharomyces cerevisiae, the radical
scavenging activity was measured using the
DPPH method, and the total phenolic and fla-
vonoid contents were estimated by the Folin–
Ciocalteu and aluminium chloride methods,
respectively. Four of the plants (Scutellaria bai
calensis, Taxillus chinensis, Rheum officinale and
Sophora japonica) showed significant antioxi-
dant activity in both the yeast model and free
radical scavenging methods. The ethanolic ex-
tract of S. japonica had the highest amounts of
phenolics and flavonoids. It was concluded
that some of the medicinal herbs investigated
in thus study are good sources of antioxidants.
Jin and Wang (2011) evaluated the anti-
oxidant activities of the ethyl acetate soluble
fraction (ESF) and the butanol soluble fraction
(BSF) of an acetone extract of agrimony [Agri
monia pilosa] using DPPH, ABTS, β-carotene-
linoleate and hydroxyl radical scavenging
assays. The IC50
(half maximal inhibitory
concentration) values of the ESF were 8.76,
7.28, 13.56 and 1.76 μg/ml, respectively, in
four assays; those for the BSF were 9.77,
7.96, 8.61 and 2.57 μg/ml, respectively. Both
the ESF and BSF had stronger antioxidant
activity than BHT, which indicates that
agrimony might be a potential source of
antioxidants.
The effect of storage time on the antioxi-
dant capacities of medicinal plants was stud-
ied by Amoo et al. (2012), who evaluated the
antioxidant properties of 21 medicinal plants
after long-term storage (12 or 16 years) in
comparison with those of freshly harvested
materials. The total phenolic contents of Arte
misia afra, Clausena anisata, Cussonia spicata,
Leonotis intermedia and Spirostachys africana
were significantly higher in stored than in
fresh materials but, with the exception of Eke
bergia capensis and L. intermedia, there were no
significant differences between the antioxi-
dant activities of stored and fresh materials.
The apparently high antioxidant activities of
stable bioactive compounds in these medi-
cinal plants offer interesting prospects for the
identification of novel principles for applica-
tion in food and pharmaceutical formulations.
Although most studies on the antioxi-
dant capacities of TCMPs have been con-
ducted in vitro, the antioxidant effects of some
plants have been confirmed in vivo. An ex-
ample is given by the study of Xia et al. (2011),
who investigated the effects of Panax notogin
seng (as the Chinese traditional medicine
Radix Notoginseng, which is prepared from
the roots of the herb P. notoginseng) given as
a dietary supplement on oxidative stress in
male Sprague Dawley rats maintained on a
high-fat diet. P. notoginseng improved hepatic
antioxidant status of the rats as assessed by
superoxide dismutase and glutathione perox-
idase activities and reduced levels of lipid
peroxidation. It is suggested that the plant
can improve lipid profiles, inhibit peroxida-
tion and increase the activity of antioxidant
enzymes, and is, thereby, likely to reduce the
risk of coronary heart disease associated with
oxidative stress.
The antioxidant capacities of the plant
extracts largely depend on the composition
of the extracts. Sample preparation is the cru-
cial first step in the study of antioxidant ac-
tivity of a plant because it is necessary to
extract antioxidants from the plant material
before their antioxidant capacity can be
evaluated, as well as to separate and identify
the natural antioxidants involved. Further-
more, the antioxidant capacity of the plant
extract depends not only on the composition
of the extract and the extraction method but

20 Li Sha et al.
also on the test system used. Because of the
different extraction and evaluation methods
used, it is very difficult to summarize and
compare the antioxidant capacities of the
TCMPs that have been reported in the litera-
ture. Table 2.1 attempts to do this by sum-
marizing data on the antioxidant capacities
and total phenolic contents of a selection of
TCMPs that were taken from selected stud-
ies that employed the same extraction condi-
tions and evaluation methods (Li et al., 2007;
Li et al., 2008; Gan et al., 2010a,b; Song et al.,
2010). The high correlation that was found
between antioxidant capacity and total
phenolic content indicated that phenolic
compounds were a major contributor to the
antioxidant activity of these plants (see also
Figs 2.1 and 2.2). Furthermore, the strong
correlation between values obtained from
the TEAC and FRAP assays implied that the
antioxidants in these plants were capable of
scavenging free radicals and reducing oxi-
dants (see Fig. 2.3).
2.3 Natural Antioxidants from

Traditional Chinese Medicinal Plants
Although antioxidant capacities of many TC-
MPs have been evaluated, the individual anti-
oxidants within them have seldom been
separated and identified. A single plant could
contain highly complex profiles of antioxidant
compounds, and these may be present at very
low concentrations. Various techniques have
been developed for the separation of antioxi-
dants from plants, with thin-layer chromatog
raphy (TLC), open column chromatography
and high-performance liquid chromatog-
raphy (HPLC) the most widely used (Tsao
and Deng, 2004; Li et al., 2011). In recent years,
high-speed counter-
current chromatography
(HSCCC) has also been used for the separ-
ation and purification of antioxidants from
TCMPs (Li and Chen, 2001a,b, 2004a,b,c,
2005a,b,c, 2009; Li et al., 2002, 2004). HSCCC
eliminates the irreversible adsorptive loss,
denaturation and contamination of natural
antioxidants that occur as a result of the solid
support matrix that is used in the conven-
tional chromatographic column, because there
is no solid support matrix in the HSCCC col-
umn (Li and Chen, 2007).
Tung et al. (2009) showed that the ethyl
acetate fraction from Acacia confusa bark
showed strong superoxide radical scaven-
ging activity, reducing power and ferrous
ion-chelating ability, and isolated and identi-
fied 16 constituents from this that included
12 benzoic acids, three cinnamic acids and
one lignin, following an in vitro antioxidant
activity-guided fractionation procedure.
In another study, Wu et al. (2008a) evalu-
ated the antioxidant activities of six xanthone
glycosides from the herb Polygala hongkongen
sis according to their scavenging activities
against DPPH and hydroxyl radicals and
their reductive activities towards Fe3+
. Of the
six, mangiferin showed potential scavenging
effects on DPPH and hydroxyl radicals as
well as reductive activity towards Fe3+
. In
addition, Wu et al. (2008b) isolated and identi-
fied 26 specific phytocompounds, including
three aromatics, three benzophenones, three
flavonoids, three isocoumarins, one phloro-
glucinol, six steroids and seven xanthones
from Garcinia multiflora using a bioactivity-
guidedisolationmethod.Themajorantioxidant
components were 2,4,3′,4′-tetrahydroxy-6-me
thoxybenzophenone and 1,3,6,7-tetrahydroxy-
xanthone.
Yuan et al. (2008) examined the antioxi-
dant activity of camellianin A from Adinandra
nitida. The results showed that camellianin A
could significantly inhibit lipid peroxidation
in a linoleic acid emulsion system, and also
scavenge DPPH and hydroxyl radicals in a
dose-dependent manner.
The antioxidant and free radical scaven-
ging activities of baicalein, baicalin, wogonin
and wogonoside from the roots of Scutellaria
baicalensis were measured in different sys-
tems by Gao et al. (1999). The results from
electron spin resonance (ESR) measurements
showed that baicalein and baicalin (i) scav-
enged hydroxyl, DPPH and alkyl radicals in
a dose-dependent manner, (ii) significantly
protected cells against H2
O2
-induced injury in
a cultured human neuroblastoma SH-SY5Y
cell system and (iii) effectively inhibited the lipid
peroxidation of rat brain cortex mitochondria
induced by Fe2+
-ascorbic acid, AAPH or NA-
DPH (nicotinamide adenine dinucleotide

Table 2.1. Antioxidant efficacy and total phenolic contents of traditional Chinese medicinal plants
(including fungi).a
Scientific name
FRAP value
(μmol Fe(II)/g)b
TEAC value
(μmol Trolox/g)c
Total phenolic
content (mg GAE/g)d
Acanthopanax gracilistylus W.W. Smith 170.19 ± 3.96 125.08 ± 7.32 10.23 ± 0.20
Achyranthes bidentata Blume 12.54 ± 1.30 24.79 ± 3.55 1.34 ± 0.06
Achyranthes longifolia Mak. 18.66 ± 1.62 37.05 ± 2.11 3.15 ± 0.08
Agadtacge rygisa O. Kuntze. 95.19 ± 4.53 46.31 ± 2.39 4.10 ± 0.07
Agrimonia pilosa Ledeb. 255.39 ± 6.24 175.22 ± 2.56 14.10 ± 0.45
Akebia trifoliata (Thunb.) Koidz. 102.18 ± 4.32 29.15 ± 1.29 2.38 ± 0.11
Alisma orientale (Sam.) Juz. 5.54 ± 0.74 25.69 ± 2.11 3.90 ± 0.16
Alpinia galanga (L.) Willd. 82.21 ± 2.92 45.45 ± 0.82 4.25 ± 0.10
Alpinia katsumadai Hayat 42.89 ± 0.95 31.51 ± 0.99 2.52 ± 0.08
Alpinia oxyphylla Mig. 14.5 ± 0.4 10.0 ± 0.7 4.79 ± 0.05
Amomum tsao-ko Crevost et Lemarié 130.16 ± 2.85 100.61 ± 1.71 7.15 ± 0.17
Amomum villosum Lour. 117.57 ± 1.43 80.16 ± 0.97 9.29 ± 0.13
Amomun kravanh Pierre ex Gagnep. 43.54 ± 2.73 25.50 ± 0.88 2.77 ± 0.14
Anemarrhena asphodeloides Bunge 83.80 ± 0.75 63.19 ± 1.24 10.45 ± 0.06
Angelica biserrata Yuan et Shan 68.99 ± 3.26 32.67 ± 2.03 7.63 ± 0.58
Angelica dahurica Benth. et Hook 27.36 ± 0.49 20.79 ± 3.67 2.94 ± 0.11
Angelica sinensis (Oliv.) Diels 27.3 ± 0.04 14.4 ± 0.2 6.23 ± 0.02
Arctium lappa L. 223.68 ± 8.28 74.66 ± 0.53 16.94 ± 1.7
Ardisia japonica (Thunb.) Blume 170.2 ± 4.39 164.1 ± 2.39 13.58 ± 0.03
Arisaema consanguineum Schott 1.05 ± 0.18 0.78 ± 0.14 0.24 ± 0.02
Artemisia anomala S. Moore 10.94 ± 1.18 32.77 ± 3.99 3.15 ± 0.02
Artemisia apiacea Hance 48.72 ± 1.44 30.83 ± 1.63 8.57 ± 0.26
Artemisia argyi H. Lév. et Vaniot 241.19 ± 13.98 127.73 ± 4.63 12.87 ± 0.23
Artemisia capillaris Thunb. 158.87 ± 7.50 106.55 ± 3.63 8.38 ± 0.20
Asparagus cochinchinensis (Lour.) Merr. 9.3 ± 0.06 3.6 ± 0.04 2.97 ± 0.06
Aster tataricus L. f. 14.77 ± 0.89 47.38 ± 1.43 5.56 ± 0.21
Astragalus complanatus Bunge 29.8 ± 0.2 40.2 ± 1.3 6.94 ± 0.13
Astragalus membranaceus
(Fisch.) Bunge
9.1 ± 0.6 5.2 ± 0.02 2.84 ± 0.05
Atractylodes lancea (Thunb.) DC. 28.15 ± 0.25 17.61 ± 2.56 2.41 ± 0.41
Atractylodes macrocephala Koidz. 9.0 ± 0.08 5.6 ± 0.3 2.79 ± 0.01
Bambusa breviflora Munro 115.74 ± 3.91 82.46 ± 1.03 9.03 ± 0.26
Baphicacanthus cusia (Nees) Bremek. 1.23 ± 0.16 0.97 ± 0.55 1.15 ± 0.01
Belamcanda chinensis (L.) DC. 71.39 ± 2.14 76.83 ± 3.04 20.14 ± 0.39
Benincasa hispida (Thunb.) Cogn. 57.28 ± 4.34 40.81 ± 0.42 4.21 ± 0.21
Biota orientalis (L.) Endl. 181.64 ± 11.84 135.95 ± 13.29 9.12 ± 0.59
Bletilla striata (Thunb.) Reichb. f. 27.24 ± 2.09 38.47 ± 2.33 2.75 ± 0.14
Boehmeria nivea (L.) Gaud. 139.10 ± 1.92 132.78 ± 9.35 10.07 ± 0.44
Brassica alba L. Boiss 64.87 ± 2.55 53.51 ± 3.3 3.34 ± 0.37
Buddleja officinalis Maxim. 284.19 ± 0.20 130.82 ± 2.59 28.82 ± 0.60
Bupleurum chinense DC. 32.05 ± 2.22 19.93 ± 0.29 3.41 ± 0.21
Caesalpinia sappan L. 313.50 ± 44.66 417.48 ± 10.57 40.97 ± 0.12
Campsis grandiflora Thunb. 96.68 ± 10.58 101.59 ± 1.97 8.93 ± 0.10
Capsella bursa-pastoris (L.) Medic. 69.99 ± 7.85 41.37 ± 4.01 4.35 ± 0.09
Carthamus tinctorius L. 26.05 ± 1.19 97.60 ± 6.58 7.26 ± 0.05
Celosia argentea L. 1.44 ± 0.01 1.45 ± 0.16 1.73 ± 0.02
Celosia cristata L. 35.13 ± 1.79 34.83 ± 1.66 2.97 ± 0.16
Centipeda minima (L.) A. Braun et Asch. 13.31 ± 0.61 16.87 ± 2.4 2.34 ± 0.03
Cephalanoplos segetum (Bunge) Kitam. 31.55 ± 0.90 32.52 ± 3.36 1.78 ± 0.13
Chaenomeles speciosa (Sweet) Nakai 195.15 ± 2.78 107.61 ± 1.09 13.58 ± 0.13
Changium smyrnioides Wolff 0.35 ± 0.02 2.07 ± 0.07 0.50 ± 0.01
Continued

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