Studies on the production and optimization of yellow pigment extracted from the SB2 strain and evaluation of its antioxidant properties

Actinobacteria are filamentous bacteria that exist independently in soil, oceans, and the atmosphere, producing secondary metabolites with antioxidant and anti-cancer properties. Among these, the SB2 strain is a yellow-pigmented, gram-positive, coccus-shaped bacterium. Raman spectroscopy of SB2 cultures revealed a wave number (cm-1) of 1382.47, which indicates pigment production and was further supported by UV-Vis spectral analysis at 450 nm that confirmed the presence of carotenoid pigment in methanolic extracts of SB2. For optimal pigment synthesis, SB2 required a pH of 7, a temperature of 30 °C, and a nutritional medium with 1% molasses, 1.2% olive oil, and 1% peptone. The yellow pigment extracted from SB2 (500 μg ml-1) demonstrated DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity.