Study on antimicrobial properties of U.V. treated shilajit

To investigate the antimicrobial activity (antibacterial & antifungal) of U.V. treated shilajit (US) and normal shilajit (NS) and to determine the minimum inhibitory concentration (MIC) value.Methods:The antibacterial activity of NS & US was evaluated at different concentrations by agar well diffusion method against selected gram positive and gram negative organisms, MIC was determined by prescribed method and antifungal activity was also checked by the well diffusion method. Phyto chemical analysis was done by Kokate et al., 2009; Evans et al., 2002; Khandelwal et al., 1995 method.Results:NSdid not show any antimicrobial activity. However, after U.V. treatment shilajit showed the potentially good antimicrobial activity against all available bacterial strains and antifungal activity only against Penicillium chrysogenum. MICwas 2mg/ml for Bacillus subtilis, Bacillus cereus, Escherichia coli, Proteus vulgaris, 5mg/ml for Pseudomonas aeruginosa and Klebsiella pneumoniaand 3mg/ml for Staphylococcus aureus.Phyto chemical analysis showed presence of carbohydrates, triterpenes, flavonoids and cardiac glycosydes.Discussion:The results in the present study suggest that the shilajit change its antimicrobial properties by U.V. treatment, which showed good antibacterial activities. This studycould be useful to formulate the new antimicrobial bioactive compounds from U.V. Treated shilajit.