Pharmacognosy 4th semester

1. PLANT PRODUCT
SATYAJIT GHOSH
B. PHARM 4TH
SEMESTER

2. FIBERS

3.  Introduction: -
i. Fibres may be defined as any hair-like raw material directly obtainable from an animal, vegetable, or mineral source and convertible into nonwoven fabrics
such as felt or paper or, after spinning into yarns, into woven cloth.
ii. A natural fibre may be further defined as an agglomeration of cells in which the diameter is negligible in comparison with the length. Although nature
abounds in fibrous materials, especially cellulosic types such as cotton, wood, grains, and straw, only a small number can be used for textile products or
other industrial purposes.
iii. They are elastic in that they stretch when put under tension and then partially or completely return to their original length when the tension is removed.
iv. Fibers obtained from various sources can be categorized as follows: -
Plant fiber Jute, Flax, Cotton, Hemp
Animal fiber Silk, Wool
Synthetic fiber Nylon, Terylene, Orlon
From carbohydrates materials Alginate yarns, Rayon,
From protein materials Aridil, Fibroline
Mineral fiber Asbestos, Glass
 Surgical fibers: -
Name & Synonyms Biological sources Active constituents Uses
Cotton
(Absorbent cotton, Surgical
cotton, Medicinal cotton)
Epidermal trichomes of seeds of Gossypium
species (Malvaceae)
93 to 94% cellulose and
moisture-5-7 %
Surgical dressing, filtering media insulation.
Jute
(Gunny - bag fibres)
Phloem fibres of Corchorus spp., Tiliaceae
Cellulose, hemicellulose and
lignin
Manufacture of tows and gunny-bags, straining
filtration media.
Flax
Pericyclic fibres of stem of Linum
usitatissimum, Linaceae
Pecto-cellulose
Straining and filtering media, preparations of
course bags

4. Silk
Fibres obtained from silk worm cocoons of
Bombyx mori, Bombycidae
Protein known as Fibroin Sutures, ligatures
Wool
Fibres from flees of sheep Ovis aries,
Bovidae
Protein known as keratin
In the manufacture of surgical dressings like
domette, crepe bandage, flannel and blankets for
warmth.
 Plant fiber: -
COTTON
Synonyms Sources Cultivation, Collection & Preparation Chemical constituents
Evaluation or Identification or
Chemical test
Therapeutic uses and
commercial utility
Raw cotton,
purified cotton,
absorbent
cotton
Epidermal
trichomes of the
seeds of cultivated
species of the
Gossypium
herbaceum and
other species of
Gossypium,
Malvaceae
 Cotton is cultivated by means of
seed sowing method.
 The cotton plants are shrubs or
small trees that bare fruits
(capsules) after flowering.
 The capsule consists of three to five
seeds and is covered with hairs.
 The bolls are collected when ripe,
separated from the capsule, dried,
and subjected to the ginning press
for processing.
 In ginning process, hairs and seeds
are put before the roller with a small
space, which separates the
trichomes from the seeds.
 The short and long hair separated
by delinter. Short hairs are known
as ‘linters’, which are used in the
manufacturing inferior grade cotton
wool, whereas long hairs are used
for preparation of cloth.
 The seeds remain after the removal
of hair is used for the preparation of
cotton seed oil and oil cake for
domestic animal feed.
 The raw cotton so obtained is full of
impurities like the colouring matter
and fatty material.
 It is then subjected to further
purification by treating it with dilute
soda ash solution under pressure for
about 15 hours.
It consists of
90% of cellulose,
7–8% of moisture, wax,
fat and oil 0.5%,
cell content about
0.5%.
 On ignition, cotton burns with a
flame, gives very little odor or
fumes, does not produce a bead,
and leaves a small white ash;
distinction from acetate rayon,
alginate yarn, wool, silk, and
nylon.
 Dried cotton is moistened with
N/50 iodine and 80% w/w
sulphuric acid is added. A blue
colour is produced; distinction
from acetate rayon, alginate
yarn, jute, hemp, wool, silk, and
nylon.
 With ammoniacal copper oxide
solution, raw cotton dissolves
with ballooning, leaving a few
fragments of cuticle. Absorbent
cotton dissolves completely
with uniform swelling,
distinction from acetate rayon,
jute, wool, and nylon.
 In cold sulphuric acid (80%
w/w) cotton dissolves;
distinction from oxidized
cellulose, jute, hemp, and wool.
 In cold sulphuric acid (60%
w/w) cotton, is insoluble;
Cotton is used as a
filtering medium and in
surgical dressings.
Absorbent cotton absorbs
blood, pus, mucus, and
prevents infections in
wounds.

5.  It is then bleached and washed
properly, dried, and packed. The
packed cotton is then sterilized
using radiations.
distinction from cellulose
wadding and rayon.
 In warm (40°C) hydrochloric
acid it is insoluble; distinction
from acetate rayon (also silk,
nylon).
 It is insoluble in 5% potassium
hydroxide solution; distinction
from oxidized cellulose, wool,
and silk.
JUTE
Synonyms Sources Cultivation, Collection & Preparation Chemical constituents
Evaluation or Identification or
Chemical test
Therapeutic uses and
commercial utility
Gunny It consists of
phloem fibres
from the stem of
various species
of the Corchorus;
C. capsularis Linn,
C. olitorius Linn,
Tiliaceae.
 Retting is the process for the
preparation of bast fibres.
 This process is done by three
methods, that is, microbial (or
water), steam, and mechanical
process.
 The microbial or water retting
process is the oldest and the
popular method employed for the
breaking of lignin bond present
between parenchyma and
sclerenchyma.
 Then the material is washed dried to
release pectin bond which makes
the hard skin to fine thread like
fibres.
 The jute fibres are graded according
to its colour, strength and fibre
length.
 The fibres are of white to brown and
1–4 m. long.
 Jute fibres are
composed primarily of
the plant materials
cellulose and lignin.
 Jute is composed of
about
50–53% cellulose,
20% of hemicellulose
10–11% of lignin along
with other constituents
like moisture not more
than 12–13%, fats, wax,
and ash contributing to
1% each.
 It is listed as the
second most
important vegetable
fibre after cotton.
 Jute is used chiefly to
make cloth for
wrapping bales of raw
cotton, in the
preparation of sacks
and coarse cloth.
 They are also woven
into curtains, chair
coverings, carpets.
 It is even used in the
manufacture of tows,
padding splints,
filtering, and straining
medium.
 Jute is used for the
preparation of coarse
bags.
HEMP
Synonyms Sources Cultivation, Collection & Preparation Chemical constituents
Evaluation or Identification or
Chemical test
Therapeutic uses and
commercial utility
Hemp is the
pericyclic fibre
obtained from
Cannabis sativa
Hemp mainly consist of
cellulose and lignin.
 The historically
mentioned uses are
printing inks, paints,
varnishes, paper,

6. Linn., belonging to
family
Cannabinaceae
bibles, bank notes,
food, textiles (the
original Levi’s jeans
were made from
Hemp cloth), canvas
and building materials.
 Due to its high tensile
strength, bast fibres
are ideal for such
specialized paper
products as: tea bags,
industrial filters,
currency paper, or
cigarette paper.

7. HALLUCINOGENS

8.  Introduction: -
i. Hallucinogens are natural and synthetic substances that, when ingested, significantly alter one’s state of consciousness. Hallucinogenic compounds often
cause people to see (or think they see) random colours, patterns, events and objects that do not exist.
ii. People sometimes have a different perception of time and space, hold imaginary conversations, believe they hear music and experience smells, tastes and
other sensations that are not real.
iii. The other names of hallucinogens are Cartoon acid, Microdot, California sunshine, Psilocybin, Magic mushrooms.
 Hallucinogenic plants: -
Plant Biological source Chemical constituents Uses
Belladonna Atropa belladonna.; nightshade family (Solanaceae).
A perennial branching herb growing to 5-feet tall, with
8-inch-long ovate leaves. The leaves in first-year
plants are larger than those of older plants.
The flowers are bell shaped, Blue-purple or dull red,
followed by a shiny, black or purple 0.5-inch berry.
The plant is native of Europe And Asia
Atropine, hyoscyamine, atropamine,
belladonnine and Hyoscine.
 Belladonna acts upon the
cerebrospinal system, as showing
such symptoms as Dilatation of
the pupils (mydriasis),
presbyopia, obscurity Of vision,
blindness (amaurosis), visual
illusions (phantasms), Suffused
eyes, occasionally disturbance of
hearing (as ringing in the ears,
etc.), numbness of the face,
confusion Of head, giddiness and
delirium.
 Belladonna is used as a
recreational drug, diuretic,
sedative,
 Antispasmodic and mydriatic.
 It is used very successfully to
Treat eye diseases, because of its
effect of dilating the pupil.
 Atropine, an extract of
belladonna, is what an eye doctor
uses when they put liquid in your
eye before testing you for glasses.

9.  Atropine has also been used as an
antidote to Opium.
Betel nut Areca catechu, Palmaceae
A very slender, graceful palm that grows up to 100-
feet tall with a 6-inch diameter trunk.
It is native to Malaysia.
Betel nut contains arecoline alkaloids
which are comparable to nicotine in
its stimulating, mildly intoxicating
and appetite-suppressing effects on
the mind.
It also contains the alkaloids
arecaidine, arecolidine, guvacine and
guvacoline.
 Stimulant, stroke recovery,
schizophrenia, anaemia, dental
cavities, ulcerative colitis and
saliva stimulant.
 It is also used as alcoholism,
aphrodisiac, appetite stimulant,
asthma, cough, digestive aid,
diphtheria and as diuretic.
 The findings of a prior study
indicating a therapeutic
relationship between
consumption of betel nut and
symptoms of schizophrenia were
tested.
Calamus Acorus calamus, Acoraceae
A vigorous perennial herb growing up to 6-feet tall,
composed of much long, slender, grass like leaves up
to 0.75-inch-wide rising from a horizontal rootstock.
It is native to eastern North America, Europe and Asia.
Both triploid and tetraploid calamus
contain asarone.
Monoterpene hydrocarbons,
sequestrene, ketones, α - Asarone
(2,4,5-trimethoxy-1 propenyl
benzene), and β -asarone (cis-
isomer) contained in the roots
essential oils.
 It is use as an analgesic for the
relief of toothache or headache,
for oral hygiene to cleanse and
disinfect the teeth, to fight the
effects of exhaustion or fatigue
and to help cure/prevent a
hangover.
 Also used to treat a cough, made a
decoction as a carminative and as
an infusion for cholic.
 The ethyl acetate fraction of the
Acorus calamus extract (ACE) was
found to enhance adipocyte
differentiation as did
rosiglitazone. The results of
further fractionation of ACE
indicated that the active fraction
does not consist of beta-asarone,
which is a toxic component of this
plant.
 This finding suggests that ACE has
potential insulin-sensitizing
activity like rosiglitazone, and
may improve type 2 diabetes.

10.  The in vitro acetylcholinesterase
(AChE) inhibitory potential of the
hydroalcoholic extract and of the
essential oil.
Catnip Nepeta cataria, Labiatae
A hardy, upright, perennial herb with sturdy stems
bearing hairy, heart-shaped, grayish-green leaves
Native of Eurasia, naturalized in North America.
Daucosterol (beta-sitosterol 3-O-
beta-D-glucoside) was isolated from
the plant, in addition to small
amounts of beta-sitosterol,
campesterol, alpha-amyrin and beta-
amyrin was also isolated.
 It is used as a household herbal
remedy, being employed
especially in treating disorders of
the digestive system and, as it
stimulates sweating, it is useful in
reducing fevers.
 The herb’s pleasant taste and
gentle action makes it suitable for
treating colds, flu and fevers in
children.
 The leaves and flowering tops are
strongly antispasmodic,
antitussive, astringent,
carminative, diaphoretic, slightly
emmenagogue, refrigerant,
sedative, slightly stimulant,
stomachic and tonic.
Chicalote, prickly
poppy
Argemone mexicana, Papaveraceae
It is an annual herb, 1–3 feet high with prickly stems,
leaves and capsules.
It is native to tropical America.
The plant contains alkaloids as
berberine, protopine, sanguinarine,
chelerythrine, etc.
The seed oil contains myristic,
palmitic, oleic, linoleic acids, etc.
 The whole plant is analgesic,
antispasmodic, possibly
hallucinogenic and sedative.
 The fresh yellow, milky, acrid sap
contains protein-dissolving
substances and has been used in
the treatment of warts, cold sores,
cutaneous affections, skin
diseases, itches, etc.
 It has also been used to treat
cataracts.
 The sensitivity of two Gram
positive (Staphylococcus aureus
and Bacillus subtilis) and two
Gram negative (Escherichia coli
and Pseudomonas aeruginosa)
pathogenic multidrug resistant
bacteria was tested against the
crude extracts of leaves and seeds

11. of Argemone mexicana by agar
well diffusion method.
Damiana Turnera diffusa, Passifloraceae
A small shrub with smooth inch long, pale green leaves
which have dense hairs on the underside.
This plant is native to the Southwest and Mexico.
It contains Arbutin, volatile oil,
Tetraphyllin B, resins, gums, starch
and tannins
 It is used as stimulant, mild
diuretic, mild laxative,
testosterone mimetic action,
nervous restorative,
antidepressant, urinary antiseptic
anxiety and depression.
 It also is used as sexual
inadequacies with a strong
psychological or emotional
element and to establish normal
menstruation at puberty.
Datura Datura fastuosa:
It is an annual herb, 4–5 feet tall, with ovate 7- to 8-
inch leaves. It is native to India and naturalized in the
tropics of both hemispheres.
D. inoxia Mill:
It is a low-growing, spreading perennial with hairy 2-
to 4-inch leaves. It is native to Mexico and the
Southwest.
D. meteloides: It is an erect perennial herb with 2–5
inch leaves. It is native to the Southwest and Mexico.
D. stramonium:
It is a green-stemmed, hairless annual, 2–4 feet tall,
with few branches and two 8-inch-long ovate leaves.
Thin out all but the healthiest plant after
sprouting.
One steroidal constituent, datura
sterol and a tricyclic diterpene, have
been isolated for the first time
from the stem bark of Datura metel
along with beta-sitosterol and
atropine.
 The whole plant, but especially
the leaves and seed, is
anaesthetic, anodyne, anti-
asthmatic, antispasmodic,
antitussive, bronchodilator,
hallucinogenic, hypnotic and
mydriatic.
Dona Ana cactus Coryphantha macromeris, Cactaceae
A low, cylindrical cactus to 8-inch-tall branching at the
base, covered with several inch long, soft, spine-tipped
tubercles.
It is native to Mexico and West Texas.
Mainly it contains macromerine, nor-
macromerine.
It also contains phenethylamines.
It is a strong narcotic or
hallucinogenic drug.

12. Fennel Foeniculum vulgare, Umbelliferae
It is a perennial herb growing to 5-feet high, with blue
green stems and leaves. The leaves are finely divided
into threadlike leaflets.
The flower cluster is a large umbel, composed
of 15–20 yellow flowers.
This plant is native of southern Europe; naturalized in
the Western United States.
The major biologically active
constituent of Foeniculum
fruit oil was characterized as (+) -
fenchone and (E)-9- octadecenoic
acid.
It also contains anethole, methyl
chavicol, camphene, etc.
 The plant is analgesic, anti-
inflammatory, anti-spasmodic,
aromatic, carminative, diuretic,
emmenagogue, expectorant,
hallucinogenic, laxative, stimulant
and stomachic.
 The essential oil is bactericidal,
carminative and stimulant.
Pectin’s from Foeniculum vulgare
were extracted under acidic
conditions.
 The obtained pectin was mainly
composed of uronic acid but also
contained traces of rhamnose,
galactose, and arabinose.
 Extracted pectin’s were used as a
carbohydrate source to prepare
biopolymer films in the absence
and in the presence of phaseolin
protein.
 The antiulcerogenic and
antioxidant effects of aqueous
Foeniculum vulgare (FVE) extract
was studied on ethanol-induced
gastric lesions in rats.
 It was found that pretreatment
with FVE significantly reduced
ethanol-induced gastric damage.

13. TERATOGENS

14.  Introduction:
i. The natural or synthetic external agents which adversely affect the developing fetus on coming in contact with them via maternal body are termed
teratogens.
ii. These agents have the ability to permanently change the structure and function of fetal organs exposed to them during development, thus cause birth
defect.
iii. For a plant teratogenic toxin to exert its effect, it should be present in a high dose, should be able to cross the placenta, and should manifest its effect at a
particular gestation time.
iv. These toxins can even lead to fetal death or gross abnormalities. They can cause vascular disruption, oxidative stress, can target specific receptors and
enzymatic sites, can cause endocrine and CNS disruption, and may affect a single anatomical feature or an entire system.
 Factors Influencing Teratogenicity:
The factors influencing the amount of damage a teratogen can cause are:
a- Dose or level of exposure of the teratogen,
b- Heredity,
c- Age of the teratogen,
d- Any other negative influences (for example, several teratogens or a teratogen combined with poor health).
 Examples:
i. Methanolic extracts of Asparagus racemosus can cause gross deformities, can increase the rate of re-absorption, and may also cause intrauterine growth in
the fetus.
ii. The seeds of Malus domestica (apple) and Prunus cerasus (cherry) contain cyanogenic glycosides which are fatal in nature.

15. iii. Solanum tuberosum (potato), Solanum melongena (eggplant), and Lycopersicon esculentum (tomato) contain solanidanes and spirosolanes (suspected
teratogens) in their edible parts.
 Given below are the examples of some highly beneficial medicinal plants, but are known/suspected teratogens:
a- Astragalus
b- Colchicum autumnale
c- Datura stramonium
d- Vinca rosea
e- Veratrum

16. NATURAL ALLERGENS

17.  Introduction: -
i. Allergens are inciting agents of allergy, i.e. the substances capable of sensitizing the body in such a way that an unusual response occurs in hypersensitive
person.
ii. Allergen may be biologic, chemical or of synthetic origin. It is common to speak about the substances, such as pollens, dust, etc., as natural allergens.
iii. The allergy (hypersensitivity) may be defined as a specific immunologic reaction to an immunogen—a normally harmless substance (allergen).
iv. Sneezing is always considered to be a symptom of a cold but sometimes it is an allergic reaction to something in the air. According to reports available
approximately 30% population suffers from some sort of allergic syndrome.
v. Following are predisposing factors which make the person hypersensitive to allergens:
a- Hereditary tendency to allergic response
b- Dysfunction of the endocrine glands
c- Increased excitability of sympathetic and parasympathetic nervous systems
d- Absorption of metabolic and catabolic substances
e- Hepatic dysfunction and
f- Psychic influences
 Types of allergens: -
The allergens can be classified on the basis of types of symptoms, which depend on the shock organs affected by the particular allergens and its route of entry
into the body:
a- Inhalant allergens
b- Ingestant allergens
c- Injectant allergens

18. d- Contactant allergens
e- Infectant allergens
 Inhalant allergens:
i. Inhalant allergens are airborne substances as chemicals, causing respiratory disease, inflammation in the nose and lungs. Inflammation in the nose is
manifested by sneezing, lacrimation, itching and swelling of nose and eyes. The condition is known as sinusitis or hay fever.
ii. Air pollution, both indoor and outdoor, plays a significant role in the aggravation of airway disease in the asthmatics and may contribute to the overall
increase in asthma morbidity.
iii. Symptoms of allergies to airborne substances are:
a- Sneezing often accompanied by a runny or clogged nose
b- Coughing and postnasal drip
c- Itching eyes, nose and throat
d- Allergic shiner (dark circles under the eyes caused by increased blood flow near the sinuses)
e- The ‘allergic salute’ (in a child, persistent upward rubbing of the nose that causes mark on the nose)
f- Watering eyes, conjunctivitis (an inflammation of the membrane that lines the eye lids causing red-rimmed, swollen eyes and crusting the eyelids)
iv. As soon as the allergens land on mucous membrane, a chain reaction occurs that leads the mast cells in these tissues to release histamine and other
chemicals. These powerful chemical contract certain cells of some small blood vessels in the nose, which allow fluid to escape causing the nasal passage
to swell resulting in nasal congestions.
v. The allergens that can cause airborne allergies (inhalant allergens) include pollens, dust, mites, mould spores and animal allergy (epidermis or dander).

19. Pollen allergens: -
i. Pollens are the tiny, egg-shaped, round, angular, square, rectangular or otherwise shaped male cells (organ) of flowering plants. These microscopic,
powdery granules are necessary for plant fertilization.
ii. The average pollen particle size is less than the width of an average human hair. Most pollen grains are single entities but some may be two-compound,
three-compound, tetrad, or so forth.
iii. These pollens can be further classified into two types:
a- Anemophilous (wind pollinated): -
Anemophilous pollens are usually small 15–45 μ in diameter, light, non-adhesive and relatively smooth and are produced by plain looking plants, e.g.
trees (oak, walnut); grasses (bermuda grass and timothy) and weeds (ragweed, plantain).
b- Entomophilous (insect pollinated): -
Entomophilous pollens are usually larger in size (up to 200 μ in diameter), heavier, adhesive and may be somewhat spiny. Plants are scented, with
coloured flowers such as clover, hollyhock, honey suckle and rose.
Most common allergic reactions are produced by wind pollinated (anemophilous) pollens, because of their light weight and the dry nature; these pollen
grains are carried for long distances.
List of plant or tree producing pollens (allergens): Alfalfa, almond, apple, acacia, barley, blue grass, canary grass, cherry, eucalyptus, gladiolus, hazelnut,
juniper, mulberry, mustard, lemon and related species of citrus.
 Ingestant allergens:
i. Allergens which are present in food stuff and swallowed are termed ingestant (food allergy). A food allergy is an immune system response to a food.
ii. Once the immune system decides that a particular food is harmful, it creates specific antibody to it. The gastrointestinal symptoms are mainly affected by
the food allergens, but they also cause skin rash, puffed lips and tongue, migraine, rhinitis or other symptoms like severe eczema of hand and feet.

20. iii. The effects of food allergens are not localized to one organ or area of the body, but it may transfer to other organs by the blood. Thus, an atopic
dermatitis, is developed by patients.
iv. Some most common food allergens ingested by patients are milk, egg, peanut, tree nut (walnut, cashew nut, etc.), fish, shellfish, soy, wheat, orange
juice, cod liver oil or other vitamins containing fish liver oils.
v. In addition to the above-mentioned normal food, there are food additive, which also could be allergic to any individual, viz. mannitol, sorbitol,
polysorbates, malt-dextrin, citrus, bioflavonoids, artificial preservatives, artificial colours, citrus pectin, talc, soy lecithin, gluten, soy flour, rice flour,
alfalfa, potato starch and gum acacia.
vi. Most satisfactory method of combating food allergens is elimination of the offending substance from the diet. Dairy milk allergy is a specific immunologic
antibody– antigen reaction due to a lacto-albumin, because heating and boiling alter this protein. Milk allergy may result in severe dermatitis, recurrent
rhinorrhea, bronchitis and asthma.
 Injectant allergens:
i. Injectant allergens cause symptoms similar to those of the antibiotics, e.g. penicillin, cephalosporin and semisynthetic penicillin, etc. Itching of the palms
of the hands and the soles of the feet, erythema and peeling of the skin are characteristic.
ii. In severe cases anaphylactic shock may occur. The natural sources of injectable allergens are produced by the sting of bees, hornets and wasps.
iii. The allergens injected by the stings of such insects can induce severe local and constitutional reactions sometimes causing death. In addition to penicillin
products, other injectable that may cause allergies are liver extract, antitoxins and the glandular products.
 Contactant allergens:
i. A number of plants and their products have been identified as the causes of contact allergies. The plant most responsible for contact dermatitis in North
America belongs to9 the Anacardiaceae family, primarily the genus Toxicodendron (Rhus) and includes poison ivy, oak and sumac.

21. ii. The allergen component of these plants, called urushiols (a phenolic compound) are found in the oleoresin fraction and are derivatives of
pentadecylcatechol or heptadecylcatechol.
iii. Many plants of Compositae family, which include the rag weeds, also cause contact dermatitis and the allergens responsible had been identified as
Sesquiterpenoids lactone.
iv. Other plants species, which can give rise to contact allergic reactions are Ruta graveolens, asparagus, ornamental ‘dumb cane’ (Dieffenbachia seguine),
buck wheat, butter cups, catalpa leaves, chrysanthemums, ginkgo leaves, lobelia, marigolds, may-apple, osage orange, flowering spurge, snow on the
mountains and smart weeds.
 Infectant allergens: -
i. Allergy caused by the metabolic product of living microorganism in the human body, such as the continual presence of certain types of bacteria,
protozoas, moulds, helminthes and other parasites in the body of human being that are responsible for chronic infection for which patients are not aware.
ii. Often the metabolic product of their growth causes some patient sensitized and the patient may exhibit allergic symptoms, which does not response
positively to routine skin test for inhalant allergens.
iii. In such patients, bacterial metabolic wastes are considered to be infectant allergens. The continuous presence of growth products and metabolic waste of
parasitic organism such as hookworms, tape worms, pinworms, threadworms and dermatophytes are referred as infectant allergens.