In Vitro Anticancer Activity of Staphyloxanthin Pigment Extracted from Staphylococcus gallinarum KX912244, a Gut Microbe of Bombyx mori .

The present study reports the in vitro biological nature of the pigment produced by Staphylococcus gallinarum KX912244, isolated as the gut microflora bacterium of the insect Bombyx mori . The purified pigment was characterized as Staphyloxanthin based on bio-physical characterization techniques like Fourier transform infrared spectroscopy, high performance liquid chromatography, Proton nuclear magnetic resonance spectroscopy (1 H NMR), Liquid chromatography-Mass spectroscopy and Gas chromatography-Mass spectroscopy. The Staphyloxanthin pigment presented considerable biological properties including in vitro antimicrobial activity against pathogens Staphylococcus aureus , Escherichia coli and Candida albicans ; in vitro antioxidant activity by % DPPH free radical scavenging activity showing IC50 value of 54.22 µg/mL; DNA damage protection activity against reactive oxygen species and anticancer activity evaluated by cytotoxicity assay against 4 different cancer cell lines like the Dalton's lymphoma ascites with IC50 value 6.20 ± 0.02 µg/mL, Ehrlich ascites carcinoma having IC50 value 6.48 ± 0.15 µg/mL, Adenocarcinomic human alveolar basal epithelial cells (A549 Lung carcinoma) bearing IC50 value 7.23 ± 0.11 µg/mL and Mus mucus skin melanoma (B16F10) showing IC50 value 6.58 ± 0.38 µg/mL and less cytotoxicity towards non-cancerous human fibroblast cell lines (NIH3T3) with IC50 value of 52.24 µg/mL. The present study results suggest that Staphyloxanthin acts as a potential therapeutic agent especially due to its anticancer property.