Actinobacteria, particularly from under-studied habitats, are often endowed with diverse biological properties. In the present study, about 17 actinobacterial strains were isolated from Sabarimala forest — an understudied ecosystem in Western Ghats, India and screened for their pigment producing potential. Pinkish brown soluble pigment producing Streptomyces sp. strain S45 was selected and screened for antibacterial and anti-HIV activity. The bioactivity of ethyl acetate extract of the strain S45 showed maximum zone of inhibition against Staphylococcus aureus ATCC 29213 (17.3±0.4 mm) and Bacillus cereus (15.6±0.6 mm). Also, it showed anti-HIV activity with the IC50 value of 8.75 µg/mL. The bioactive pigment isolated from the strain S45 was partially purified and characterized using UV absorption. In bio-autography, an antibacterial compound found to be active against S. aureus ATCC 29213 and its MIC values ranged between 25-1.56 µg/mL. Variables such as glucose, rhamnose, soybean meal and CaCl₂, pH 7 and temperature 30℃ were found to influence bioactive pigment production. Potential strain S45 was identified as Streptomyces species on the basis of microscopic, cultural, physiological and 16SrRNA analysis. Results suggest that the Streptomyces sp. S45 strain explored in this study could be a promising candidate for isolation of antibacterial and anti HIV pigment.

中文翻译：

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链霉菌细胞外色素的抗菌和抗HIV活性。从印度萨巴里马森林土壤中分离出的S45

放线菌，特别是来自研究不足的栖息地的放线菌，通常具有多种生物学特性。在本研究中，从印度西部高止山脉一个被研究不足的生态系统Sabarimala森林中分离出大约17种放线菌菌株，并对其色素生产潜力进行了筛选。粉红棕色可溶性色素，产生链霉菌。选择菌株S45，并筛选其抗菌和抗HIV活性。S45菌株乙酸乙酯提取物的生物活性显示出对金黄色葡萄球菌ATCC 29213（17.3±0.4 mm）和蜡状芽孢杆菌的最大抑制区（15.6±0.6毫米）。此外，它还具有抗HIV活性，IC50值为8.75 µg / mL。从菌株S45分离的生物活性颜料被部分纯化并使用UV吸收表征。在生物自显影中，发现一种抗菌化合物对金黄色葡萄球菌ATCC 29213具有活性，其MIC值在25-1.56 µg / mL之间。发现诸如葡萄糖，鼠李糖，豆粕和CaCl ₂，pH 7和温度30℃的变量会影响生物活性色素的产生。根据显微镜，文化，生理和16SrRNA分析，潜在菌株S45被鉴定为链霉菌种。结果表明链霉菌sp。在这项研究中探索的S45菌株可能是分离抗菌和抗HIV色素的有前途的候选者。