Rameshwar Dayal

Abstract

Phytochemistry is the study of extraction, isolation and identification of plant chemicals viz; alkaloids, iridoides, phenolics, steroids, coumarins, terpenoides and others. These secondary metabolites play key role in the development of many new sources of plant - derived products. The isolation and characterization of new bioactive constituents from plants have become possible with the advent of latest sophisticated techniques such as chromatographic methods, multidimensional NMR and mass spectrometry. About one hundred twenty compounds were characterized using GC-MS for essential oils and latest spectroscopic methods like 2D NMR and other techniques for the pure compounds of which four compounds namely; artoflavanone, stipulin, luteolin-4'- rutinoside and quercetin-3-0-digalactoside were found to be new. A number of compounds were found to possess medicinal activity. This paper describes the isolation and characterization of chemical constituents from the different parts of nine plant species having biological activity.

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Virendra Singh Rana , Rameshwar Dayal

Abstract

Studies to determine the appropriate month of harvesting of Vitex negundo leaves for the isolation of optimum amount of essential oil have been reported. The maximum oil yield (0.28%) was obtained in the month of October.

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P. L. Soni , Rameshwar Dayal , Vineet Kumar

Abstract

Over exploitation of non-wood forest products (NWFPs) is threatening forest ecosystems in India. Harvesting NWFPs from threatened and endangered species has led to search of new alternatives. Thus there is an urgent need to find abundantly available and new substitutes as well as to develop simple and suitable technologies for sustainable utilization of NWFPs to save environment. This paper describes some of the eco-friendly technologies/processes developed by Forest Research Institute, Dehra Dun in recent years from abundantly available forest/agro biomass. The new technologies will go a long way in saving the fragile ecosystem of the country.

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Rameshwar Dayal

Abstract

Since his existence on this planet man has had to depend on Nature for sustenance and survival. Medicinal plants have been used by him to keep himself healthy. According to the studies on ethnomedicine and folk medicine about 2000 species are newly identified as drug yielding plants and are well known for their use in about 4000 drug industries of various Indian systems of medicine. Phytochemical examination of a number of them has been carried out and active ingredients, isolated, identified are being currently used as drugs. Chemical examination of hitherto unexplored medicinal plants will help in discovering new drugs.

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Mukhtar Ahmad , Rameshwar Dayal , R. K Mishra , P. C Dobhal

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Natural forest products have long been known to possess insecticidal, insect growth regulating and antifeedant properties. Doring present studies extractives of some forest produce including acetone and alcohol extracts of bark and ischolar_mains of Dalbergia stipulacea, leaves of Eucalyptus hybrid and Adina conlifolia, ursolic acid and bryonolic acid were evaluated as insect antifeedant against poplar defoliator Clostera eupreata (Lepidoptera : Notodontidae). Ursolic acid (separated from Euealyptru hybridleaves extract) has shown maximum antifeedant activity and gave over 92 per cent protection of poplar leaves from its pest. It was followed by alcohol and acetone extracts of Eucalyptru hybrid leaves, bryonolic acid, acetone extract of D. stipulacea bark, alcohol extract of A. cordifolia leaves etc. Solvents play important role in extracting active ingredient of specific nature as acetone extracts of D.stipulacea were found more effective than their alcohol extracts while solvents (acetone and alcohol) did not sbow any antifeedant activity on their own.

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Rameshwar Dayal

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Oleoresins of Pinus merkusii and Pinus insulari (Khasi pine) from Arunachal Pradesh were studied. On hydrodistillation the two resins gave 23% and 21 % of turpentine oil respectively. The oils were analysed by GLC. P. merkusii oil was found to contain α -pinene (57.05%). And -carene (39.35%) while α-pinene (59.36%), β -pinene (31.20%) and longifolcne (0.78%) were present in that of P insularis.

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Rameshwar Dayal , M. L. Maheshwari

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The essential oils obtained from the leaves of two hybrids namely FRI-4, FRI-5 and from E. camaldulensis, E, tereticornis, E. deglupta and E. robusta were analysed by GLC. Fifteen compounds viz.α-pinene, camphene,β-pinene, phellandrene, limonene, cineole,γ-terpinene, p-cymene, citronellyl, linalool, terpine-1-ene-401,citronellyl, acetone, borneol,α-terpineol and piperitone in varying ratios have been identified in all of them. Physiochemical properties of the oils have also been determined.

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