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Article Information Actinomycetes are among the industrially and therapeutically relevant microorganisms and are known to produce useful products such as antibiotics, enzymes, vitamins etc. Among actinomycetes, genus Streptomyces is known to produce a great array of products. In the present study, we have recovered a Streptomyces species RAMPP-065 from Western ghats soil of Kudremukh, Karnataka, India and determined its antimicrobial and antioxidant activity. The isolate was recovered on Starch casein agar and identified as Streptomyces species on the basis of cultural, microscopic, staining and biochemical characteristics. Fermentation was carried out in Starch casein broth for 7 days and filtered. The culture filtrate was extracted with ethyl acetate and the solvent was evaporated to get the extract. Antimicrobial activity of extract was tested against 8 bacteria and 2 fungi by agar well diffusion method. Gram positive bacteria were more sensitive to extract than Gram negative bacteria. Among fungi, susceptibility to extract was higher in Candida albicans than Cryptococcus neoformans. The extract showed a dose dependent scavenging of DPPH free radical as revealed by bleaching of DPPH radical color with increase in concentration of extract. In ferric reducing assay, the absorbance was found to increase with increase in extract concentration. Total phenolic content of extract, as estimated by Folin-Ciocalteau method, was 59mg Gallic acid equivalents/gram. The scavenging and reducing activity of extract were lesser when compared to reference compounds. The soils of Western ghats are rich sources for microorganisms with potent biological activities. To the best of our knowledge, this is the first report on bioactivity of Streptomyces species from Kudremukh soil. Further studies are to be carried out to characterize the Streptomyces isolate and the active principles present in the extract.

Article InformationThe present study was carried out to estimate the content of total phenolics, flavonoids, negundoside and agnuside and to determine antibacterial, cytotoxic and antioxidant efficacy of methanol extract of two varieties of Vitex negundo namely V. negundo var. negundo (Vnvn) and V. negundo var. purpurascens (Vnvp). Total phenolic and flavonoid content of leaf extracts were estimated by Folin-Ciocalteau reagent and Aluminium chloride colorimetric estimation method respectively. Negundoside and agnuside content were estimated using HPLC. Antibacterial activity of both the extracts was tested by Agar well diffusion assay. Cytotoxicity of extract was evaluated by Brine shrimp lethality bioassay. Antioxidant activity of extracts was determined by DPPH free radical scavenging and Ferric reducing assay. The content of total phenolics and flavonoid were higher in extract of Vnvp. Negundoside and agnuside contents were high in Vnvn and Vnvp respectively. Leaf extract of Vnvp was shown to display marked antibacterial, cytotoxic and antioxidant activity when compared with extract of Vnvn. Both the varieties of V. negundo showed marked antibacterial, cytotoxic and antioxidant activity. The extract of Vnvp displayed marked bioactivities than that of extract of Vnvn. The presence of high phenolic and flavonoid content could be attributed to the marked bioactivities of Vnvp.