In the present work, a newly isolated marine bacterium, Micrococcus sp. MP76, from coastal area of Persian Gulf around Bushehr province, Iran, was identified with the ability to produce bioactive compounds.
The pigment production was optimized by changing carbon and nitrogen sources in bacterial growth media at 28° C and 220 rpm for 5 days. Partial purification of the pigment was carried out using suitable solvents.
Maximum pigment extract was achieved (1.4 g/l) when cultured in the medi um containing 0.5% (v/v) molasses, 0.5% (w/v) peptone, 1% (w/v) sea salt, 0.01% (w/v) potassium phosphate, and 0.05% (w/v) yeast extract, pH=7.0. Antibacterial effect assessment of the extract against pathogenic bacteria revealed the MIC values in the range of 4.2–7.5 mg/ml depending on different pathogens. The pigment extracted from medium supplemented by molasses and ammonium sulfate had 81% radical scavenging activity, and its IC 50 value was 0.28 mg/ml.