Bergenin and neobergenin belongs to isocoumarin group of phytochemicals. They have been isolated from leaves and roots of Fluggea micrcarpa Blume (Euphorbiaceae). The two isocoumarins demonstrated significant protection against aspirin-induced peptic ulcer and pylorus-ligation in animal models. The mechanism of gastro-protective action of bergenin and neobergenin was attributed to increased prostaglandin production ₁.

Luvangetin, a pyranocoumarin isolated from seeds of Aegle marmelos Correa (Rutaceae) has gastro-protective action similar to bergenin and neobergenin however mode of action was thought to be different ₂.

Eclipta alba L. is used as hepatoprotective in Ayurveda. In rats against carbon tetrachloride induced hepatotoxicity. In vivo studies with active fractions from ethanolic extract of Eclipta alba leaves were undertaken. One fraction was containing wedelolactone and other fraction was containing apigenin, 4-hydroxybenzoic acid and protocatcheuic acid. The second fraction was found to be more active hepatoprotective₃.

Kutkins isolated from Picrorhiza kurrooa ex Benth. (Scrophulariaceae) has shown significant curative activity in vitro in primary cultured rat hepatocytes against toxicity induced by thioacetamide, galactosamine, and carbon tetrachloride₄. In another study, active constituent of Picrorhiza kurrooa showed a dose dependent hepatoprotective activity against oxytetracycline induced hepatic damage in rats₅.

Hepatoprotective activity of C-phycocyanin isolated from Spirulina platensis L. was investigated. Intraperitoneal administration of single dose of phycocyanin in a dose of 200mg/kg one to three hours prior to carbon tetrachloride and R-(+)-pulegone, demonstrated significant hepatoprotective activity₆.

Ursolic acid isolated from leaves of Eucalyptus terelicomisdemonstrated hepatoprotective effect against thiacetamide, galactosamine and carbon tetrachloride in rats. Pretreatment with ursolic acid increased the viability of liver cells. In large doses, ursolic acid demonstrated choleretic effect. Further the authors concluded that hepatoprotective activity of ursolic acid was comparable to silymarin₇.

Bioassay guided activity of fruit extract of Terminalia belerica identified 3, 4, 5-trihydroxy benzoic acid (gallic acid), as hepatoprotective principle ₈.

Andrographis paniculata Nees. is well known medicinal plant for its usefulness in liver diseases. In Ayurveda it is known as Bhunimba or Kalmegha. It is used as bitter tonic and febrifuge. Because of bitter taste it is popularly known king of bitters. It contains diterpene lactones (andrographolide, neoandrographolide and kalmeghin).

Andrographolide produced dose dependent chloretic effect evidenced by increase in bile flow, bile salt and bile acids in animal models. The cholretic effect of Andrographis paniculata was found to be better than silymarin₉.

Chebulin an anthraquinone glycoside found in flowers of Terminalia chebula Retz (Combretaceae) popularly known as haritaki in Ayurveda has antispasmodic activity similar to papaverine ₁₀. Chebulin is however considered to be purgative principle of Terminalia chebula.

Anti diarrheal activity of piperine, the principle alkaloid of Piper longum and Piper nigrum L. (Piperaceae) was investigated against diarrhea induced by castor oil, magnesium sulphate and arachidonic acid in rats. Piperine significantly inhibited diarrhea produced by above laxatives and aperients at a dose of 8 and 32 mg/kg p.o. dose. It further inhibited castor oil induced enter pooling explaining prostaglandin inhibiting effect₁₁.

Experiments conducted with Tylpohorine a phenanthroindalizidine alkaloid present in Tylophora asthmatica (L. f.) Wight & Arn. (Asclepiadaceae) in various animal models have shown significant anti-inflammatory, anti-anaphylactic and anti-spasmodic activities. Bronchodilator activity of Tylophora asthmatica is attributed to tylophorine ₁₂.

Guggulsterones found in Commiphora mukul have been reported to inhibit cholesterol synthesis in the liver via antagonism to the farsenoid X receptor and the bile-acid receptor₁₃. Since then several clinical trials have been carried out with standardized extract of Commiphora mukul in treating hypercholesterolemia ₁₄,₁₅, ₁₆.

Jatamansone a sesquiterpene ketone found in Nardostachys jatamansi DC (Valerianaceae) has been reported to have antiarrhythmic activity however details of the study are missing₁₇.

Bacosides belong to group of compounds known as triterpenoid saponins ₁₈. They are considered to be active constituents of Bacopa monnieria L. (Scrophulariaceae) popularly known as Brahami in Ayurveda₁₉. Bacoside-A and bacoside-B have been identified. The bacoside- A content of Bacopa monnieria L. is about 2.5-3.0%.

Extensive pharmacological studies with standardized extracts of Bacopa monniera Linn has demonstrated that the medicinal plant improves the acquisition, retention and retrieval of learned tasks. A study found that bacosids A and B were active in facilitating effects of Bacopa monniera Linn. on learning schedules₂₀. The bacosides further decreases the incidence of retrograde amnesia produced by immobilization induced stress, electro-conclusive shock and scopolamine. Bacoside A and B were found to facilitate the capacity for mental retention in rats and were active in both positive and negative reinforcement experiments ₂₁.

Ginkgo biloba is well known for its pharmacological activities. The medicinal plant contains bioflavonoids, pronathocyanidins, diterpenes and a toxic compound ginkgolic acid. In an experimental study, aimed at anxiolytic activity of ginkgolic acid conjugates (including several salicylates) demonstrated significant anxiolytic activity. In contrast, toe commercial preparations EGb 761 and Ginkocer (devoid of ginkgolic acid conjugates failed to evoke significant anxiolytic activity ₂₂. The study was concluded that ginkgolic acid conjugates might be the active constituents of Ginkgo biloba responsible for the anxiolytic activity.

Gossypin is a bioflavonoid obtained from yellow petals of Hibiscus vitifolius L. (Malvaceae). It has anti-nociceptive activity similar to opium alkaloids and involving multi-neurotransmitter systems. It acts through cholinergic and GABAergic pathways. It seems to have potential analgesic activity with free from tolerance and dependence ₂₃. Cerpegin is an oxazolone alkaloid isolated from Ceropegia juncea Roxb ₂₄. It has shown analgesic effect against acetic acid induced writhing in mice ₂₅.

Gossypin was found to significantly reduce the rat paw, edema and the increased vascular permeability induced by various phlogistic agents. It produced significant inhibition of the accumulation of pouch fluid and granulation tissue formation in the carrageenin induced granuloma pouch in rats. Gossypin was also found effective against the adjuvant and formalin induced chronic arthritis in rats ₂₆.

Betulinic acid, a triterpene isolated from Nelumbo nucifera L. demonstrated significant anti-inflammatory activity when tested in carrageenin and 5-hydroxytryptamine induced paw edema. The activity was comparable to betamethasone and phenylbutazone ₂₇.

Premnazole, an isoxazole alkaloid isolated from Premna integrifolia L. and Gmelina arborea L. (Verbenaceae) demonstrated significant anti-inflammatory activity in reducing cotton pellet-induced granuloma formation in rats. The anti-inflammatory activity was comparable to that of phenylbutazone₂₈. Gangetin-a pterocarpenoid isolated from Desmodium gangeticum has been reported to have anti-inflammatory and analgesic activities₂₉.

Jatamansone a sesquiterpene ketone found in Nardostachys jatamansi DC (Valerianaceae) has been reported to have tranquillizer activity however details of the study are missing₃₀.

Jatamansone sesquiterpene ketone found in Nardostachys jatamansi DC (Valerianaceae) and pongamol, a flavonoid found in Pongamia pinnata (L.) Merr. (Fabaceae) are reported to have significant anticonvulsant activity₃₁, ₃₂.

In a study CNS activity of swertiamarin, a secoiridoid glycoside obtained from Swertia chirata - (Wall.) C.B.Clarke. was evaluated. It was found that swertiamarin significantly reversed the mangiferin-induced CNS-stimulating effects in albino mice and rats ₃₃.

Clausenol a carbazole alkaloid isolated from alcoholic extract of stem-bark of Clausena anisata (Willd) Hook (Rutaceae) has shown antibacterial activity ₄₄,₄₅. The phytochemical was found to be active against bacteria and fungi. Preliminary investigations of xanthochymol, active principle of Garcinia xanthochymus Hook.f. (Guttiferae) demonstrated antimicrobial activity ₄₆.

In 1970 a study reported antifungal activity of Withaferin A₄₇. Fungistatic activity of Zaluzanin-D isolated from Vernonia arborea L. (Asteraceae) was reported₄₈. Lignans (termilignan and thannilignan), 7-hydroxy-3', 4'-(methylenedioxy) flavone and anolignan B isolated from Terminalia belerica (Gaertn.) Roxb. (Combertaceae) have significant antimalarial and antifungal activities ₄₉.

Glycyrrhizin, triterpenoid saponin found in Glychyrrhiza glabra L. (Fabaceae) inhibited the plaque formation in DNA and RNA viruses. It has been proposed that glycyrrhizin blocks the first steps on viral replication as well as the viron exit from the capside ₅₀.

Amarogentin, a secoiridoid glycoside isolated from Swertia chirayita (Roxb ex. Flem) Karst] (Gentianaceae) is inhibitor of topoisomerase I enzyme of Leismania donovani ₅₁,₅₂

Palasonin (terpene anhydride), active principle isolated from seeds of Butea monosperma L. (Fabaceae) inhibited glucose uptake and depleted the glycogen content in Ascaridia galli. In another study interaction of palasonin with glycolytic enzymes and succinic acid production in Ascaris lumbricoides was postulated as possible mechanism of action ₅₃,₅₄.

Gentistein, the active compound of Flemingia vestita Benth. (Fabaceae) was investigated for anthelmintic activity against Fasciolopsis buski, the large intestinal fluke of swine and human host. Genistein induced effect on the activity of nitric oxide synthase which may be the possible mode of action ₅₅.

Swerchirin, xanthone from Swertia chirayita (Roxb ex. Flem) Karst] (Gentianaceae) has hypoglycemic activity. Researchers compared the effects of mode of action of three different hypoglycemic agents; centipiperalon, tolbutamide and swerchirin in normal as well as diabetic rats. Except in rats with severe pancreatic damage, swerchirin showed better glucose lowering effect compared to tolbutamide ₅₆.

Karanjin, a flavone showed significant hypoglycemic activity with a single dose of 0.5 mg/kg in normal rats. However it was ineffective in alloxan- induced diabetic rats₅₇.

Solasodine an alkaloid of Solanum xanthocarpum L. (Solanaceae) demonstrated antifertility activity in male and dogs. The alkaloid on oral administration resulted in inhibition of spermatogenesis and sperm motility. The mechanism of action of solasodine may be attributed to inhibition of testosterone release. Solasodine seems to be valuable antifertility agent of plant origin ₅₉.

Embelin a plant benzoquinone and active constituent of Embelia ribes Burm (Myrsinaceae) is another valuable antifertility agent of plant origin. Several animal studies have proved efficacy of embelin as antifertility agent. Several theories have been postulated for its anti fertility activity but authentic one is still to come. Plumbagin, napthoquinone from Plumbago rosea L. (Plumbaginaceae) has anti fertility activity similar to embelin₆₀.

Mucuna prurita Baker (Fabaceae) is well known spermopiotic plant of Ayurveda. In a study the total alkaloidal content (mucuadine, mucuadinine, mucucuadinine, pruriendine, mucunine, mucunadine, nicotine) of Mucuna prurita demonstrated increased spermatogenesis in albino rats₆₁.

Embelin demonstrated 100 per cent anti-implantation activity in albino rats and rabbits when given in a dose of 10mg/kg.