Production of hydroxy marilone C as a bioactive compound fromStreptomyces badius

Hydroxy marilone C is a bioactive metabolite produced from the culture broth of Streptomyces badius isolated from Egyptian soil. Hydroxy marilone C was purified and fractionated by a silica gel column with a gradient mobile phase dichloromethane (DCM):methanol then Sephadex LH-20 column using methanol as a mobile phase. It was subjected to many procedures such as infrared (IR), nuclear magnetic resonance (NMR), Mass spectroscopy (MS) and UV spectroscopy for elucidation of its structure. It was evaluated for antioxidant, cytotoxicity against human alveolar basal epithelial cell line (A-549) and human breast adenocarcinoma cell line (MCF-7) and antiviral activities; showed that the maximum antioxidant activity was 78.8% at 3 mg/ml after 90 min. and the IC₅₀ value against DPPH radical found about 1.5 mg/ml after 60 min. Using MTT assay the effect of the pure compound on the proliferation of A-549 cells and MCF-7 cells was 443 μg/ml and 147.9 μg/ml, respectively, while for detection of antiviral activity using Madin-Darby canine kidney (MDCK) cells the maximum cytotoxicity was at 27.9% and IC₅₀ was 128.1 μg/ml. The maximum concentration required for protecting 50% of the virus-infected cells against H1N1 viral cytopathogenicity (EC₅₀) was 33.25% for 80 μg/ml. These results indicated that the hydroxy marilone C has potential antitumor and antiviral activities.