ANTIMICROBIAL PHYTOCHEMICALS IN GINKGO BILOBA L LEAVES FROM UTTARAKHAND HIMALAYA

Abstract

Recent upsurge in the therapeutic potential of medicinal plants as a source of newlinephytochemicals is gaining momentum all over the globe. Among other issues of research, newlinescreening of medicinal plants for active constituents and evaluating the biological activity deserve newlinepriority attention in view the increasing demand of herbal medicine in different systems of newlinemedicine. Ginkgo biloba leaves contain pharmaceutically important flavonoid glycosides and newlineginkgolides which improve blood flow, act as antioxidants and also used as memory enhancers and newlineanti-vertigo agents. While Ginkgo has been well recognized for medicinally important active newlineingredients, the species has received limited attention for its antimicrobial properties. Keeping this newlinebackground in view, Ginkgo plants were selected for detailed investigations for nutritional and newlinephytochemicals constituents, standardization of methodology for extraction and quantification of newlineactive ingredients and antimicrobial activity present in the leaf extracts of Ginkgo biloba growing newlinein the Indian Himalayan Region. newlineFive trees, located in Almora and Nainital districts of Uttarakhand, were selected for the newlinecollection of leaf material in different seasons (i.e. spring, rainy and autumn). These five trees were newlinegenetically different. Extraction of active ingredients from powdered leaf samples was performed newlinein 5 solvent systems (3 pure solvents i.e., methanol, ethyl acetate, n-Butanol), combination of newlineacetone/water (3:2) - 1 set and aqueous (1 set). The nutritional and phytochemical values could be newlineassessed for different biochemical parameters including proximate, trace elements, total phenolic, newlineflavonoid contents and antioxidant activity using spectrophotometric methods. Quantification of newlineGinkgo leaf flavonoid glycosides was conducted using HPLC following standard procedure along newlinewith different extraction techniques. Optimization of time and temperature for detection of newlineginkgolides and bilobalide was performed by TLC method. Factorial analysis was performed to correlate the influence