Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
J Appl Microbiol. 2021 May;130(5):1508-1522. doi: 10.1111/jam.14877. Epub 2020 Oct 18.
This study aimed to isolate actinomycetes from marine environments and examine their antifungal activity against Talaromyces marneffei both in vitro and in vivo.
Nineteen out of 101 actinomycete extracts were active and further determined for their minimum inhibitory concentrations (MIC). Three extracts of AMA50 that isolated from sediment showed strong antifungal activity against T. marneffei yeast (MICs ≤0·03-0·25 µg ml ) and mould (MICs 0·5-16 µg ml ) forms. The hexane extract from the cells of AMA50 (AMA50CH) exhibited the best activity against both the forms (MIC ≤ 1 µg ml ). Three extracts from AMA50 killed the melanized yeast cells at 0·5 µg ml . The AMA50CH was further tested for protective effects in Caenorhabditis elegans model. At concentrations of 1-8 µg ml , the AMA50CH prolonged survival of T. marneffei-infected C. elegans with a 60-70% survival rate. The composition of AMA50CH was determined by gas chromatography-mass spectrometry. The major components were n-hexadecanoic acid, tetradecanoic acid and pentadecanoic acid. Sequencing analysis revealed that isolate AMA50 belonged to the genus Streptomyces.
The AMA50CH from Streptomyces sp. AMA50 was the most effective extract against T. marneffei.
Talaromyces marneffei is one of the most important thermally dimorphic pathogenic fungi. These results indicated the potency of marine-derived actinomycete extracts against T. marneffei both in vitro and in vivo.
本研究旨在从海洋环境中分离放线菌，并研究其对马尔尼菲青霉菌的体外和体内抗真菌活性。
从 101 个放线菌提取物中分离出 19 个具有活性的提取物，并进一步测定其最小抑菌浓度（MIC）。从沉积物中分离出的 AMA50 的 3 个提取物对马尔尼菲青霉菌酵母（MICs≤0.03-0.25μg/ml）和霉菌（MICs 0.5-16μg/ml）形式具有很强的抗真菌活性。AMA50 细胞的正己烷提取物（AMA50CH）对两种形式均表现出最佳活性（MIC≤1μg/ml）。3 种提取物可在 0.5μg/ml 杀死黑素化酵母细胞。进一步在秀丽隐杆线虫模型中测试 AMA50CH 的保护作用。在 1-8μg/ml 浓度下，AMA50CH 可延长感染马尔尼菲青霉菌的秀丽隐杆线虫的存活时间，存活率为 60-70%。通过气相色谱-质谱法确定 AMA50CH 的成分。主要成分是正十六烷酸、十四烷酸和十五烷酸。测序分析表明，分离株 AMA50 属于链霉菌属。
来自链霉菌属 AMA50 的 AMA50CH 是最有效的抗马尔尼菲青霉菌提取物。
马尔尼菲青霉菌是最重要的热双相致病性真菌之一。这些结果表明海洋来源的放线菌提取物对体外和体内的马尔尼菲青霉菌具有潜在的作用。
