Phytochemistry, bioactive potential and chemical characterization of metabolites from marine microalgae (Spirulina platensis) biomass

This study aimed to investigate the phytochemical profile, the antibacterial and antioxidant activities of mass cultured Spirulina platensis and the structural characterization of the methanolic extracts. S. platensis was isolated from estuary and mass cultured in the laboratory, methanol was used for extraction, and the yield was calculated as 16%. The seven phytochemicals were quantified by standard procedure, and the phenol was found maximum 96.7 µg/mg followed by alkaloid 89.5 µg/mg. The antibacterial activity was performed by disc diffusion method, and the maximum activity was noted against Salmonella typhi (19 mm) followed by Escherichia coli (12 mm). The antioxidant effect was recorded as concentration-dependent, and in all, the antioxidant effect was recorded in higher concentration level including as standards. In FT-IR spectral analysis, the active functional groups alkyl halide and amine were recorded simultaneously in ¹H NMR analysis, 11 chemical shifts were recorded, and it revealed the stretching of alkane, allylic, benzylic, ketone, alkyne and esters. From the results, the present study concluded that S. platensis is an alternate source of pharmaceutical industry due to its phytochemical profile and bioactive potential.