An endophytic actinomycete strain SKH1-2 isolated from Musa (ABB) cv. ‘Kluai Sao Kratuep Ho’ collected in Suphan Buri province (14° 54′ 22.5″ N/100° 04′ 50″ E), Thailand, was identified as Streptomyces pseudovenezuelae based on phenotypic and chemotaxonomic characteristics, and 16S rRNA sequence analyses. A chemical investigation led to the isolation of two polyketide molecules from the n-butanol crude extract of the strain SKH1-2 culture broth. The compounds were purified using various chromatographic techniques and identified using spectroscopic methods compared with earlier published data. Compound 1, chartreusin, is known as an anti-Gram (+) bacterial compound and was active against Bacillus subtilis ATCC 6633, Kocuria rhizophila ATCC 9341 and Staphylococcus aureus ATCC 6538p with MIC values of 3.1, 1.6 and 12.5 μg/mL, respectively. Compound 2, lumichrome, did not show activity against all tested microbes. To our knowledge, this is the first report of chartreusin and lumichrome isolated from S. pseudovenezuelae. Taken together, it could be proved that Thai plant species are valuable reservoirs of interesting endophytic actinomycetes producing several interesting biologically active compounds.

中文翻译：

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表征链霉菌属的两个聚酮。从麝香根（ABB）分离的SKH1-2 cv。'Kluai Sao Kratuep Ho'。

从Musa（ABB）cv分离的内生放线菌菌株SKH1-2 。根据表型和化学分类学特征以及16S rRNA序列分析，在泰国素攀武里府（14°54′22.5” N / 100°04′50” E）收集的“ Kluai Sao Kratuep Ho”被鉴定为伪链霉菌。化学研究导致从菌株SKH1-2培养液的正丁醇粗提物中分离出两个聚酮化合物分子。使用各种色谱技术对化合物进行纯化，并与早期公布的数据进行比较，采用光谱法进行鉴定。化合物1（沙特里菌素）被称为抗革兰氏（+）细菌化合物，对枯草芽孢杆菌具有活性ATCC 6633，亲核科氏菌（Kocuria rhizophila） ATCC 9341和金黄色葡萄球菌ATCC 6538p，MIC值分别为3.1、1.6和12.5μg/ mL。化合物2（发光铬）并未显示出对所有测试微生物的活性。据我们所知，这是chartreusin和光色素从孤立的第一份报告S. pseudovenezuelae。综上所述，可以证明泰国植物物种是有趣的内生放线菌的有价值的贮藏库，产生了几种有趣的生物活性化合物。