Evaluation of Anti-inflammatory property of Melanin from marine Bacillus sp BTCZ31

 Objectives: To evaluate the anti-inflammatory property of melanin from marine Bacillus spp. BTCZ31.Methods: Radical scavenging property of melanin was determined by 2,2-Diphenyl-1-picrylhydrazyl and metal chelation assays, which was furtherconfirmed by electron paramagnetic resonance (EPR) spectroscopy. Anti-inflammatory property of melanin was explored in vitro in RAW264.7cell line using cyclooxygenase (COX), Lipoxygenase (LOX), Myleoperoxidase (MPO), cellular nitrite inhibitory assays. Cytotoxicity of melanin wasdetermined using 3-(4,5 dimethythiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay.Results: BTCZ31 melanin showed radical scavenging activity of 67.55% and ferrous ion chelating activity of 97.88%. EPR spectrum showed sharppeaks indicating the presence of unpaired electrons. Melanin inhibited the activity of COX and LOX enzyme with IC50 values of 104.34 μg/mL and10.5 μg/mL, respectively. It also reduced the activity of MPO and cellular nitrite levels. Cytotoxic concentration of melanin was found to be 105.4 μg/mL(IC50).Conclusion: Bacillus spp. BTCZ10 melanin can be a potential anti-inflammatory agent. Further in vivo evaluations are needed for confirming theactivity, leading to therapeutic applications.Keywords: Anti-inflammatory, Antioxidant, Bacillus spp., Bacteria, Marine, Melanin