BACKGROUND:Marine actinomycetes are efficient producers of new secondary metabolites that show different biological activities,including antibacterial,antifungal,anticancer,insecticidal,and enzyme inhibition activities.METHODS:The morphological,physiological,and biochemical properties of the strain Streptomyces sp.VITPSA were confirmed by conventional methods.Antibacterial,anti-oxidant,anti-inflammatory,anti-diabetic,and cytotoxic activities of Streptomyces sp.VITPSA extract were determined.The media were optimized for the production of secondary metabolites.Characterization and identification of secondary metabolites were conducted by high-performance liquid chromatography,gas chromatography-mass spectroscopy,and Fourier transform infrared spectroscopy analysis.RESULTS:The strain showed significant antibacterial,anti-oxidant,and cytotoxic activities,moderate anti-inflammatory activity,and no satisfactory anti-diabetic activity.The ethyl acetate extract of Streptomyces sp.VITPSA showed maximum antibacterial activity against two gram-positive and gram-negative bacteria at 0.5 mg/mL.The antioxidant potential of the crude extract exhibited strong reducing power activity at 0.5 mg/mL with 95.1％ inhibition.The cytotoxic effect was found to be an IC5o of 50 μtg/mL on MCF-7 cell lines.Experimental design of optimization by one-factor analysis revealed the most favorable sucrose,yeast extract,pH (7.25),and temperature (28℃) conditions for the effective production of secondary metabolites.CONCLUSION:This study revealed that Streptomyces sp.VITPSA is an excellent source of secondary metabolites with various bioactivities.