• Phenols probably constitute the largest group pf plant
• Phenols are utilized as Colouring agents. Flavouring agents,
aromatizers and antioxidants. E.g.
• Simple phenolic compounds
• Coumarins and glycosides
• Anthraquinones and glycosides
• Naphthaquinone and glycosides
• Flavones and related flavonoid glycoside
• Anthocyanidins and anthocyanins
• Lignans and lignin
Lignan: Dimeric derivatives
• Dimeric compounds formed essentially by the union of the two
molecules of a phenylpropene derivative.
• Not synthesized by lignin biosynthetic pathway.
• Unlike lignin, optically active and probably arise by stereospecific,
reductive coupling between the middle carbons of the side chain of
• Some 300 lignans have been isolated and categorized into a number
of groups according to structural features.
• Important pharmaceutical examples are the lignans of Podophyllum
spp. which appear to be formed from two molecule of coniferyl
alcohol or the corresponding acid with subsequent modification;
apparently, a sinapic acid derivative, as might be expected by the
inspection of the podophyllotoxin molecule, is not involved.
• Lignans, cited are not however, necessarily the therapeutically
active constituents of the plant.
• Neo-lignans are also derived from the same unit as lignans but
the C6-C3 moieties are linked head to tail or head to head and
not through the beta-beta’ carbons.
• They occur in the heart wood of trees of the Mangoliaceae,
Lauraceae and Piperaceae.
• Example: Guaicum officinale resin Guaicum sanctum
• Myristica fragrans, Piper cubeba
• Magnolia officinalis Magnolia obovata:
• Magnolol: CNS Action: depressant, muscle relaxant, anti
platelet, antimicrobial, anti-tumour, anticancer, insecticidal
• It is an important polymeric substance, (C6-C3)n, laid down in a matrix of
cellulose microfibrils to strength certain cell wall.
• It is an essential component of most woody tissues and involves vessels,
tracheids, fibers and sclreids.
• Lignins from different biological sources vary in composition, depending on
the particular monomeric units in which they are composed.
• Variations in lignin constitutes also arise as a result of random
condensations of the appropriate alcohols with mesomeric free radicals
formed from them by the action of a laccase type (oxidase) enzyme.
• As there is no template for this non-enzymatic condensation the lignin
molecules formed vary in structure and so it is not possible to isolate lignin
as a compound of defined composition.
• In the wall, it appears to occur chemically combined with
hemicellulose and built up in greatest concentration in the
middle lamellae and in the primary walls.
• Lignified cell walls after treatment with Schultze’s macerating
fluid (HNO3+ Potassium chlorate) will show cellulose
• Acid Aniline sulphate bright yellow
• Phloroglucinol + conc. HCl pink/red
• Chlor-zinc-iodine yellow
• diverse family of organic compounds that are synthesized by plants
from the amino acid Phenyl alanine.
• Their name is derived from the six-carbon, aromatic phenyl group
and the three-carbon propene tail of cinnamic acid, which is
synthesized from phenylalanine in the first step of phenyl propanoid
• Phenylpropanoids are found throughout the plant kingdom, where
they serve as essential components of a number of structural
polymers, provide protection from UV light, defend against
herbivores and pathogens, and mediate plant-pollinator interactions
as floral pigments and scent compounds.
• Concentrations of phenylpropanoids within plants are also altered
by changes in resource availability.
• Phenylpropanoids and other phenolics are part of the
chemical composition of sporopollenin.
• This substance found in pollen is not exactly known, due to its
unusual chemical stability and resistance to degradation by
enzymes and strong chemical reagents. Analyses have
revealed a mixture of biopolymers, containing mainly long
chain fatty acids, phenylpropanoids, phenolics and traces of
• Tracer experiments have shown that phenylalanine is a major
precursor, but other carbon sources also contribute. It is likely
that sporopollenin derives from several precursors that are
chemically cross-linked to form a rigid structure
Lignan & Polyketide
• Syn: May apple, Wild mandrake
• Source: dried roots and rhizomes of American:
Podophyllum peltatum & India: Podophyllum
• Family: Podophyllaceae (Berberidaceae)
• GS: America (US-Virginia, Kentucky, North
carolina, Tennessee, Indiana, Canada)
• Indian: Tibet, China, Afghanistan, Himalayas
• The rhizomes and roots are obtained from wild grown plants
growing at an altitude of 3000 to 4000 m.
• Underground rhizomes remain dormant in winter and
produce aerial shoots in April to May.
• Shoots flower during summer and die in November
• Rhizomes and roots are dug up in spring or autumn, washed,
cleaned and dried in the sun
• The drug collected in the month of may has higher resin
content than the collected in November.
• Actually the roots contain more resin than rhizomes and
hence roots are preferred.
• P. peltatum
• 2-8% resinous material as podophyllin, Lignan dvt:
podophyllotoxin, alpha & beta peltatin, (Lignan: in form of
glycoside), Desmethyl podophyllotoxin,
• Flavonoid: quercetin, kaempferol, essential oil, Starch
• P. hexandrum
• 7-15% Resin as Podophyllin
• 40% podophyllotoxin
• Chemical Test:
• Alcoholic ext. + strong copper acetate- brown ppt with
Indian podophyllum & green color without ppt with
• Cyto-toxic, venereal disease, Warts,
• Podophyllotoxin is semisynthetically converted to
etoposide potent anticancer agent for lung & testicular.
• Its GIT irritant, drastic purgative in moderate uses
• American Podophyllum
• Not so
• The CaOx crystals are fewer
and smaller (30-60-100
• Less resin 2-8 %
• Contains alpha & beta
• Podophyllotoxin is less
• Indian Podophyllum
• Vascular bundles are more
• The CaOx crystals are fewer
and smaller (20-30-60 Micro
• More resin up to 7-15%
• No constituents
• Podophyllotoxin is more
• Chemical Test:
• psoralen, dissolved in alcohol + NaOH UV light
observation yellow fluorescence
• Psoralen, dissolved in small amount of alcohol, 3 times
propylene glycol, 5 times acetic acid, 40 times water UV light
observation blue fluorescence
• Aphrodisiac, antibacterial, astringent, cytotoxic, diaphoretic,
diuretic, stimulant, stomachic , tonic, lower back pain, skin
disease, bed wetting, leprosy, hair loss
3. Ammi majus
• Syn: Bishop’s weed, Laceflower, Toothpick ammi, Large
• Source: dried fruits of Ammi majus
• Family: Umbelliferae
• GS: Europe, Egypt, West africa, India
• Constituents: furanocoumarins, xanthotoxin, imperatorin,
• CT: 1) drug+ waterboilstrainfiltrate+ NaOH no rose
color distinct from Ammi visanaga
2) Alc. Ext of fruit blue fluorescence under UV light
• Uses: furanocoumarin: stimulate pigment production in skin
when exposed to bright sunlight and hence treatment of
vitiligo and psoriasis
5. Male fern (polyketide-resin)
• Syn: Filix Mass, Rhizoma filicis Maris
• Source: dried rhizome and its
surrounding frond bases of
• Family: Polypodiaceae
• GS: Europe, England, Germany,
India: JK, HP, SK at high altitude of
• Use: Potent taenicide, kills worms
and expel it out, absorption from
GIT blindness, in large dose: