Spice as Medicine; Bioactive compounds; Pharmacological properties;Health benefits

1. SPICE AS MEDICINE:
LEMONGRASS
GENUS: CYMBOPOGON
By
Kevin KF Ng, MD, PhD
Former Associate Professor of Medicine
Division of Clinical Pharmacology
University of Miami, Miami, FL. USA
Email:kevinng68@gmail.com
A Slide Presentation for HealthCare Provider Oct 2020

2. Outline of lecture
• History
• Producing and consuming countries
• Scientific classification
• Anatomy, composition, essential oil
• Bioactive compounds
• Pharmacology
• Safety issues
• Recipes
• Summary

3. What is lemongrass?
.
▪ Lemongrass is a perennial grass with long, sharp-edged
blades. It grows in dense clumps in tropical or subtropical
climates.
▪ It is grown throughout Southeast Asia, Southern India, Sri
Lanka, Central Africa, Brazil, Guatemala, the US and the West
Indies.
▪ The plants last three to four years and are harvested every
three to five months
▪ Propagation is by dividing the root clump.

4. Origin of lemongrass
▪ Most of the species of lemon grass are native to South Asia, South-east Asia and
Australia.
▪ The East Indian lemongrass (Cymbopogon flexuosus) , also known as Malabar or
Cochin grass is native to Cambodia, Vietnam, Laos, India, Sri Lanka, Burma, and
Thailand,
▪ The West Indian lemon grass (Cymbogon citratus ), is generally assumed to be of
Malaysian origin .
▪ Both the species are today cultivated throughout tropical and subtropical Asia.

5. Milestones in the history of lemongrass
https://www.newdirectionsaromatics.com/products/essential-oils/lemongrass-organic-essential-oil.html

6. Number of lemongrass and lemongrass essential oil
publications in PubMed from 1946 to 2019
https://www.ncbi.nlm.nih.gov/pubmed/?term=lemongrass+essential+oil
lemongrass
essential oil

7. Cymbopogon
The name Cymbopogon is derived
from the Greek words ‘kymbe’ (boat)
and ‘pogon’ (beard), referring to the
flower spike arrangement
https://aromaticstudies.com/lemongrass-cymbopogon-citratus/

8. Scientific classification of lemongrass

9. Botany of lemongrass
▪ The genus Cymbopogon belongs to the grass family, Poaceae (syn.
Gramineae)
▪ The Poaceae family has about 700 genera and 11,000 species widely
distributed in all regions of the world.
▪ Cymbopogon is a genus comprising about 180 species, subspecies,
varieties, and subvarities.
▪ Cymbopogon species found within the aromatherapy industry include:
▪ C. citratus (lemongrass),
▪ C. martinii var. motia and sofia (palmarosa and ginger -grass respectively),
▪ C. flexuosus (lemongrass),
▪ C. winterianus (Java citronella),
▪ C. nardus (Ceylon citronella), and
▪ C. nardus x C. jwarancusa (jamrosa).
https://aromaticstudies.com/lemongrass-cymbopogon-citratus/

10. Two main varieties of lemongrass
▪ There are two main varieties of Lemongrass:
▪ East Indian lemongrass (Cymbopogon flexuosus (Nees ex Steud.) J.F. Watson)
which is considered to have its origins in southern India and
▪ West Indian lemongrass (Cymbopogon citratus (DC ex Nees) Stapf) which is
thought to have its origin in Malaysia
▪ Cymbopogon citratus is largely used for culinary purposes,
▪ Cymbopogon flexuosus is used in essential oils and perfumes.
https://aromaticstudies.com/lemongrass-cymbopogon-citratus/

11. Top lemongrass producing countries

12. Common usage of lemongrass
▪ Food Industry
▪ Traditional or Medicinal Uses
▪ Aromatherapy with essential oil
▪ Pharmaceutical Industry
▪ Cosmetics and Perfumery Industries

13. Methods of extracting bioactive compounds from lemongrass
http://www.ifrj.upm.edu.my/21%20(02)%202014/4%20IFRJ%2021%20(02)%202014%20043.pdf

14. Botanical parts of a lemongrass plant
leaves
bulb
roots

15. Nutrient composition of lemongrass

16. Bioactive compounds of lemongrass in
root, stem-leaves and essential oil
https://www.researchgate.net/publication/271236199_A_REVIEW_ON_LEMON_GRASS_AGRICULTURAL_AND_MEDICINAL_ASPECT
oil yield 0.25-0.6%

17. Bioavailability of volatile essential oils
Adapted from https://www.youtube.com/watch?v=QicBAUFX7VA&feature=share

18. Elimination profile of geraniol after 12.5 mg
intravenous infusion to rats (2018)
Data are expressed as the mean ± SE of four independent experiments. The elimination followed an apparent first order
kinetics, confirmed by the semilogarithmic plot reported in the inset (n = 5, r = 0.963, P < 0.0001). The half-life of geraniol
was calculated to be 12.5 ± 1.5 min.
https://www.frontiersin.org/articles/10.3389/fphar.2018.00018/full

19. Pharmacokinectics and pharmacodynamics of
oral citral 500mg/kg in rats
▪ 50% of the dose was excreted within 24 hours.
▪ The metabolites were a biliary glucuronide and several acids.
▪ The metabolites that were isolated were:
▪ 3-hydroxy-3,7-dimethyl-6-octenedioic acid
▪ 3,8-dihydroxy-3,7-dimethyl-6-octenoic acid
▪ 3,9-dihydroxy-3,7-dimethyl-6-octenoic acid
▪ E- and Z-3,7-dimethyl-2,6-octadienedioic acid
▪ 3,7-dimethyl-6-octenedioic acid
▪ E-3,7-dimethyl-2,6-octadienoic acid
▪ The urinary metabolites of citral appeared to arise from metabolic pathways other
than a nucleophilic addition to the double bond.
https://www.sigmaaldrich.com/life-science/nutrition-research/learning-
center/plant-profiler/cymbopogon.html

20. Pharmacological properties of lemongrass
https://www.sigmaaldrich.com/life-science/nutrition-research/learning-center/plant-profiler/cymbopogon.html

21. Inhibitory effect of lemon grass oil against fungal strains by
(A) disc diffusion, and (B) vapor diffusion methods. (2014)
DGIZ: Diameter of growth inhibition zone;
LGEO: lemon grass essential oil.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4170112/

22. Cytotoxicity and antimicrobial effects of citronella oil
(Cymbopogon nardus) and commercial mouthwashes on
S. aureus and C. albicans biofilms in prosthetic materials. (2019)
https://www.ncbi.nlm.nih.gov/pubmed/31606567

23. Lemongrass ( Cymbopogon flexuosus) essential oil demonstrated anti-
inflammatory effect in pre-inflamed human dermal fibroblasts (2017)
▪ Lemongrass (Cymbopogon flexuosus) essential oil (LEO), which has citral as its main component, has
exhibited anti-inflammatory effect in both animal and human cells. In this study, we evaluated the anti-
inflammatory activity of commercially available LEO in pre-inflamed human dermal fibroblast cells. We
first studied the impact of LEO on 17 protein biomarkers that are critically associated with inflammation
and tissue remodeling. LEO significantly inhibited production of the inflammatory biomarkers vascular
cell adhesion molecule 1 (VCAM-1), interferon gamma-induced protein 10 (IP-10), interferon-inducible T-
cell alpha chemoattractant (I-TAC), and monokine induced by gamma interferon (MIG); decreased levels
of the tissue remodeling biomarkers collagen-I and III, epidermal growth factor receptor (EGFR), and
plasminogen activator inhibitor (PAI-1); and inhibited the immunomodulatory biomarker macrophage
colony-stimulating factor (M-CSF). Furthermore, we studied the impact of LEO on genome-wide gene
expression profiles. LEO significantly modulated global gene expression and robustly impacted signaling
pathways, many of which are critical for inflammation and tissue remodeling processes. This study
provides the first evidence of the anti-inflammatory activity of LEO in human skin cells and indicates that
it is a good therapeutic candidate for treating inflammatory conditions of the skin.
https://www.researchgate.net/publication/315503809_Lemongrass_Cymbopogon_flexuosus_esse
ntial_oil_demonstrated_anti-inflammatory_effect_in_pre-inflamed_human_dermal_fibroblasts

24. Lemongrass effects on IL-1beta and IL-6 production by
macrophages (2009)
Cymbopogon citratus has been widely recognised for its ethnobotanical and medicinal
usefulness. Its insecticidal, antimicrobial and therapeutic properties have been reported,
but little is known about its effect on the immune system. This work aimed to investigate
the in vivo effect of a water extract of lemongrass on pro-inflammatory cytokine (IL-
1beta and IL-6) production by macrophages of BALB/c mice. The action of lemongrass
essential oil on cytokine production by macrophages was also analysed in vitro. The
chemical composition of the extract and the oil was also investigated. Treatment of mice
with water extract of lemongrass inhibited macrophages to produce IL-1beta but induced
IL-6 production by these cells. Lemongrass essential oil inhibited the cytokine production
in vitro. Linalool oxide and epoxy-linalool oxide were found to be the major components
of lemongrass water extract, and neral and geranial were the major compounds of its
essential oil. Taken together, these data suggest an anti-inflammatory action of this
natural product.
http://www.aromaticscience.com/lemongrass-effects-on-il-1beta-and-il-6-
production-by-macrophages/

25. Antipyretic Effects of Citral and Possible Mechanisms of Action:
systemic administration of lipopolysaccharide (LPS) to rats. (2017)
https://www.semanticscholar.org/paper/Antipyretic-Effects-of-Citral-and-Possible-of-
Em%C3%ADlio-Silva-Mota/6e58043fee3a0d9f22990c702ce3610a169e603d/figure/1
iL-1β TNF-α
iL-6 PGE2

26. EFFECT OF C. CITRATUS ROOT EXTRACT, FLOWER EXTRACT, AND
GLIBENCLAMIDE ON
BLOOD SUGAR IN DEXAMETHASONE INDUCED HYPERGLYCEMIA
http://ijpsr.com/bft-article/study-of-antidiabetic-effect-of-lemongrass-cymbopogon-
citratus-aqueous-roots-and-flower-extracts-on-albino-mice/?view=fulltext
BLOOD SUGAR

27. Effect of citral on glucose tolerance test.
Effect of citral on glucose tolerance. Glucose tolerance test.
Mean peak glucose levels of Group A (127 ± 4 mg/dL), Group B
(123 ± 3mg/dL), Group C (120 ± 3 mg/dL), drug control (145 ±
4 mg/dL), and diet control groups (132 ± 4 mg/dL) at the end
of experiment. Mean glucose levels are shown. All data are
mean ± SD. Mean peak glucose levels of Group A, Group B, and
Group C are significantly lower than the drug control (one-way
ANOVA, Holm–Sidak method, P < 0.05)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3113383/
A
B
C

28. Effect of Cymbopogon Citratus and Citral on Vascular Smooth
Muscle of the Isolated Thoracic Rat Aorta (2012)
Citral may partially act through the NO pathway while a vasodilator prostaglandin may mediate the effect of LE.
https://pubmed.ncbi.nlm.nih.gov/22675383-effect-of-cymbopogon-citratus-
and-citral-on-vascular-smooth-muscle-of-the-isolated-thoracic-rat-aorta/

29. Anti-Platelet aggregation activity of Cymbopogon ambiguous
bioactive compounds(2010)
Infusions and decoctions of Cymbopogon ambiguus have been used traditionally in
Australia for the treatment of headache, chest infections and muscle cramps. The aim of
the present study was to screen and identify bioactive compounds from C. ambiguus that
could explain this plant's anti-headache activity. A dichloromethane extract of C.
ambiguus was identified as having activity in adenosine-diphosphate-induced human
platelet aggregation and serotonin-release inhibition bioassays. Subsequent fractionation
of this extract led to the isolation of four phenylpropenoids, eugenol, elemicin, eugenol
methylether and trans-isoelemicin. While both eugenol and elemicin exhibited dose-
dependent inhibition of ADP-induced human platelet serotonin release, only eugenol
displayed potent inhibitory activity with an IC(50) value of 46.6 microM, in comparison to
aspirin, with an IC(50) value of 46.1 microM. These findings provide evidence to support
the therapeutic efficacy of C. ambiguus in the non-conventional treatment of headache
and inflammatory conditions.
https://www.researchgate.net/publication/40846789_Isolation_of_Bioactive_Com
pounds_That_Relate_to_the_Anti-Platelet_Activity_of_Cymbopogon_ambiguus

30. Effect of Lemongrass Oil, an Essential Oil, on
Serum Cholesterol (1989)
▪ To test the hypothesis that non-sterol mevalonate pathway end products lower serum
cholesterol levels, we asked 22 hypercholesterolemic subjects (315±9 mg cholesterol/dl)
to take a daily capsule containing 140 mg of lemongrass oil, an essential oil rich in
geraniol and citral. The paired difference in serum cholesterol levels of subjects
completing the 90-day study approached significance (P<0.06, 2-tailed t-test). The
subjects segregated into two groups, one consisting of 14 subjects resistant to the
protocol and the other consisting of 8 subjects who responded. Paired differences in
cholesterol level at 30, 60 and 90 d for resistant subjects were +2±6, +2±7 and −1±6
mg/dl; paired differences for the responding subjects were −25±10 (p<0.05), −33±8
(p<0.01) and −38±10 (p<0.025), respectively. The paired difference (+8±4) in the
cholesterol levels of six responders 90 days after the discontinuation of lemongrass oil
was not significant.
https://link.springer.com/article/10.1007/BF02535203

31. Effect of lemongrass essential oil on serum cholesterol (1989)
https://link.springer.com/article/10.1007/BF02535203
not significant

32. The cancer cells that are sensitive to geraniol in vitro.
No clinical studies available at this time
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4809657/

33. In vitro cytotoxicity and anticancer effects of citral nanostructured
lipid carrier on MDA MBA-231 human breast cancer cells (2019)
https://www.nature.com/articles/s41598-018-38214-x

34. Anticancer effect of lemongrass oil and citral on cervical
cancer cell lines (2013)
https://www.researchgate.net/publication/265842609_Anticancer_effect_of_lemongrass_oil_and_citral_on_cervical_cancer_cell_lines
Hela cell line ME-180 cell lines
lemongrass oil
lemongrass oil
citral
citral

35. Lemongrass essential oil and citral suppress the
proliferation of small-cell lung cancer cells (2018)
https://www.ncbi.nlm.nih.gov/pubmed/29568932

36. Cytotoxicity of citral, lemongrass oil (LO) and geraniol
on cancer cell lines (2018)
cells
cells
https://www.sciencedirect.com/science/article/pii/S2214750018301926

37. Essential oil from Cymbopogon flexuosus suppresses
HSP90 gene expression
https://www.sciencedirect.com/science/article/pii/S2214750018301926
screening of plant based compounds inhibition by essential oil at different concentration.
HSP90 is one of the major chaperones responsible for the proper folding of cancer proteins
LO= lemongrass oil

38. Use of lemongrass essential oil
▪ Traditional/Folk Medicinal Uses
▪ Food Industry
▪ Aromatherapy
▪ Cosmetics, Toiletries and Perfumery Industries
▪ Pharmaceutical Industry

39. Safety issue of geraniol in lemongrass
▪ The United States Food and Drug Administration (FDA) recognizes
geraniol as safe for human consumption when used appropriately.
▪ The Environmental Protection Agency (EPA) exempts it from
registration when used as a pesticide or insecticide.
https://abstraxtech.com/blogs/education/what-is-geraniol-uses-benefits

40. The Effectiveness of Aromatherapy in Reducing Pain:
A Systematic Review and Meta-Analysis (2016)
https://www.hindawi.com/journals/prt/2016/8158693/fig3/

41. Commercial products of Lemongrass
▪ Fresh lemongrass
▪ Dry lemon grass
▪ Culinary lemongrass powder
▪ Lemongrass as ingredient in:
▪ Curry
▪ Tea
▪ Cakes
▪ Lemongrass essential oil

42. Lemongrass in common Thai Cuisine

43. Summary
▪ Lemongrass is a perennial plant that originated in
Southeast Asia
▪ It is cultivated for its medicinal and culinary uses.
▪ Multiple health benefits have been demonstrated in vitro
▪ However, clinical studies are few.
▪ The essential oil used in aromatherapy has been shown
to reduce pain.
▪ As a fragrant flavoring ingredient, it is enjoyed by all in
culinary cuisines.

44. ANY QUESTION?
Please contact
Kevin KF Ng, MD, PhD
Email: kevinng68@gmail.com
44