Published on: Mar 4, 2016
Transcripts - Polyketide lignan-phenylpropanoids
Lignans & Phenyl-propanoids
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 monomer.
Some 300 lignans have been isolated and
categorized into a number of groups according to
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.
• 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.
• Guaicum officinale resin Guaicum sanctum
• Myristica fragrans
• Piper cubeba
• Magnolia officinalis
• Magnolol: CNS Action: depressant, muscle relaxant, anti platelet,
antimicrobial, anti-tumour, anticancer, insecticidal
• diverse family of organic compounds that are synthesized by
plants from the amino acid phenylalanine.
• 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
• Phenylpropanoids are found throughout the plant kingdom,
where they serve as essential components of a number of
structural polymers, provide protection from ultraviolet light,
defend against herbivores and pathogens, and mediate plantpollinator interactions as floral pigments and scent
• 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 carotenoids.
• 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
• GS: America (US-Virginia, Kentucky, North carolina,
Tennessee, Indiana, Canada)
Indian: Tibet, China, Afghanistan, Himalayas
The rhizome which is about 1 m in length, is dug up cut
into pieces about 10 cm in length and dried.
2-8% resinous material as
Lignan dvt: podophyllotoxin,
alpha & beta peltatin
(Lignan: in form of glycoside)
• Chemical Test:
Alcoholic ext. + strong copper acetate- brown
ppt with Indian podophyllum & green color
without ppt with american podophyllum
-Cyto-toxic, venereal disease
-Podophyllotoxin is semisynthetically converted to
etoposide potent anticancer agent for lung &
-Its GIT irritant, drastic purgative in moderate
• Syn: Bavchi, Malaya tea
• Source: dried ripe fruits and seeds of Psoralea
• Family: Leguminosae
• GS: India, China, Srilanka, Nepal, Vietnam
• Constituents: coumarin like psoralen, isopsoralen,
psoralidin, isopsoralidin, carylifolean,
bavachromanol and psoralenol, Fixed oil 10%,
essential oil 0.05% and resin
• Seeds: Flavonoids: bavachalcone, bavachinin,
isobavachalcone, bavachin and isobavachin
• Seed oil: limonene, aelemene, betacaryophyllenoxide, 4-terpineol, linalool, geranyl
acetate, angelicin, psoralen, bakuchiol
• Chemical Test:
1) psoralen, dissolved in alcohol + NaOH UV light
observation yellow fluorescence
2) Psoralen, dissolved in small amount of alcohol, 3 times
propylene glycol, 5 times acetic acid, 40 times water UV light
observation blue fluorescence
Aphrodiasic, antibacterial, astringent, cytotoxic, deobstruent,
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 bullwort
• 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
3. Ammi majus
4. Phyllanthus (Lignan)
• Syn: Bhumyamlaki, Stone breaker
• Source: dried leaves and stem of
• Family: Euphorbiaceae
• GS: trophical zone
Kidney stones treatment
Lignans: phyllanthin, hypophyllanthine, phyltetralin, lintetralin, niranthin, nirtetralin,
nirphylline, nirurin, niruriside.
Terpenes: Cymene, limonene, lupeol and lupeol acetate.
Flavonoids. Quercetin, Quercitrin, Isoquercitrin, astragalin, rutin, physetinglucoside.
Lipids: Ricinoleic acid, dotriancontanoic acid, linoleic acid, linolenic acid.
Alkaloids: Norsecurinine, 4 - metoxy - Norsecurinine, entnorsecurinina, nirurine,
Alcanes: Triacontanal, Triacontanol.
Others. Vitamin C, tanins, saponins.
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:
-5% yellow resin: anthelmintic property
-Oleoresin: phloroglucinol dvt.
-Monocyclic dvt.: butyryl phloroglucinol,
aspidinol and acylfilicinic acid
-Bicyclic: albaspidin, flavaspidic acid
-Tricyclic: filicic acid