State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning 530007, China.
National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning 530007, China.
Mar Drugs. 2021 Sep 11;19(9):516. doi: 10.3390/md19090516.
Fusarium wilt of banana (also known as Panama disease), is a severe fungal disease caused by soil-borne f. sp. (). In recent years, biocontrol strategies using antifungal microorganisms from various niches and their related bioactive compounds have been used to prevent and control Panama disease. Here, a thermotolerant marine strain S185 was identified as , displaying strong antifungal activity against . The strain S185 possesses multiple plant growth-promoting (PGP) and biocontrol utility properties, such as producing indole acetic acid (IAA) and ammonia, assimilating various carbon sources, tolerating pH of 4 to 9, temperature of 20 to 50 °C, and salt stress of 1 to 5%. Inoculation of S185 colonized the banana plants effectively and was mainly located in leaf and root tissues. To further investigate the antifungal components, compounds were extracted, fractionated, and purified. One compound, inhibiting with minimum inhibitory concentrations (MICs) of 25 μg/disk, was identified as iturin A5 by high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and nuclear magnetic resonance (NMR). The isolated iturin, A5, resulted in severe morphological changes during spore germination and hyphae growth of . These results specify that S185 plays a key role in preventing the pathogen by producing the antifungal compound iturin A5, and possesses potential as a cost-effective and sustainable biocontrol strain for Panama disease in the future. This is the first report of isolation of the antifungal compound iturin A5 from thermotolerant marine S185.
香蕉枯萎病（也称为巴拿马病）是一种由土壤传播的真菌引起的严重真菌病，其病原体为 f. sp. （）。近年来，人们利用来自各种生境的抗真菌微生物及其相关生物活性化合物来开发生物防治策略，以预防和控制巴拿马病。在这里，我们鉴定出一株耐热海洋菌株 S185 为 ，其对 具有很强的抗真菌活性。该菌株 S185 具有多种植物促生（PGP）和生物防治实用特性，例如产生吲哚乙酸（IAA）和氨，同化各种碳源，耐受 pH 值为 4 至 9、温度为 20 至 50°C 和盐度为 1 至 5%。接种 S185 可有效定植香蕉植物，其主要定殖于叶片和根部组织。为了进一步研究其抗真菌成分，我们对化合物进行了提取、分离和纯化。一种化合物，对 的最小抑菌浓度（MIC）为 25 μg/disk，通过高分辨电喷雾电离质谱（HR-ESI-MS）和核磁共振（NMR）鉴定为伊枯草菌素 A5。分离出的伊枯草菌素 A5 导致 孢子萌发和菌丝生长过程中出现严重的形态变化。这些结果表明，S185 通过产生抗真菌化合物伊枯草菌素 A5 来防止 病原体，并且作为未来防治巴拿马病的一种具有成本效益和可持续性的生物防治菌株具有潜力。这是首次从耐热海洋 菌株 S185 中分离出抗真菌化合物伊枯草菌素 A5 的报道。
