Anti-MRSA activity of a bioactive compound produced by a marine <i>Streptomyces</i> and its optimization using statistical experimental design

Abstract

<em><strong>Objective(s):</strong></em> To address the alarming problem of methicillin-resistant Staphylococcus aureus (MRSA), herein, a marine Streptomyces capable of producing an anti-MRSA compound has been studied.<br /><em><strong>Materials and Methods:</strong> </em>Strain MN41 was morphologically and physiologically characterized and then, molecularly identified using 16SrRNA analysis. To produce the bioactive compound in large scale, a kind of submerged liquid fermentation was adopted. The antibacterial agent was purified using a silica gel column followed by a semi-preparative HPLC and the isolated metabolite was identified using mass spectrometry, Nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR). Finally, the production process was subjected to a two steps optimization using Plackett-Burman design (PBD) and Response Surface Method (RSM), respectively. In addition, the antitumor activity of the active agent was studied.<br /><em><strong>Results:</strong></em> The purified compound with a molecular weight of 421.2 was identified as a natural pyrrole-derivative. The optimization revealed a significant effect for starch, pH, calcium carbonate and peptone on the production of this anti-MRSA compound and resulted in a 218% increase in the production yield. <br /><em><strong>Conclusion:</strong></em> The isolated pyrrole-derivative showed a remarkable activity against MRSA and also showed some promising anti-tumor activity.