Pharmacognostical studies on the leaves of <i>Ophiorrhiza mungos</i> Linn. (Rubiaceae)

Abstract

AIM: The aim of the study was to carry out pharmacognostical investigation including macro-, microscopical studies, macerate studies and powder analysis in addition to (high performance thin layer chromatography) HPTLC profile of the leaves of Ophiorrhiza mungos. METHODS: Leaves of O. mungos were collected from the forests of Thenmalai, Kerala and shade dried. A few pieces of the leaf were preserved in 70 % alcohol for pharmacognostical evaluation. Preliminary phytochemical analysis and HPTLC of aqueous and alcohol extracts were carried out and camptothecin was identified by comparing the Rf values. RESULTS: O. mungos is identified by characters like the presence of interpetiolar stipules, gamopetalous corolla and inferior ovary. The leaf drug is identified by the presence of rubiaceous stomata, septate, multicellular trichomes containing crystal sand inclusion, resinous content in cells of ground tissue, vessels with spiral and pitted thickenings which serve as useful pharmacopoeial parameters. Preliminary phytochemical analysis revealed alkaloids, carbohydrates and glycosides, phytosterols, phenolic compounds, tannins and flavonoids in alcohol extract. Aqueous extract contained alkaloids, carbohydrates and glycosides, phenolic compounds, tannins, flavonoids, gums and mucilage. Petroleum ether extract contained phytosterols, fixed oils and fats. Chloroform extract contained alkaloids whereas acetone extract contained phytosterols. HPTLC indicated the presence of camptothecin in alcohol and aqueous extracts. CONCLUSION: It is concluded that these pharmacognostical investigations comprising macro-, microscopical, phytochemical studies including HPTLC profile help in the identification of the leaf drug of O. mungos besides confirming that the alcohol and aqueous extracts contained camptothecin, an useful anticancer agent.