Wei Longfeng, Zhang Qinyu, Xie Ailin, Xiao Yang, Guo Kun, Mu Shuzhen, Xie Yudan, Li Zhu, He Tengxia
Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences, Institute of Agro-Bioengineering, Guizhou University, Guiyang, China.
Guizhou Key Laboratory of Agricultural Biotechnology, Guiyang, China.
Front Microbiol. 2022 Jul 11;13:934857. doi: 10.3389/fmicb.2022.934857. eCollection 2022.
fungi can produce a wide range of secondary metabolites, and they have represented a potential resource of novel bioactive compounds. Bacterial plant diseases have a serious impact on the sustainable development of agriculture worldwide, so it is necessary to use natural antibacterial compounds in microorganisms to control plant pathogens. This study was conducted to investigate the bioactive compounds of xj, three plant pathogens ( T-37, EC-1, and RS-2) were used as indicator bacteria, according to the biological activity tracking, five compounds were isolated from xj spore powder, and characterization of compounds was done by NMR (H-NMR and C-NMR) and EI-MS and was identified as ergosterol (1), β-sitosterol (2), 5-pentadecylresorcinol (3), 5-hydroxymethyl-2-furancarboxylic acid (4), and succinimide (5). Compounds 3 and 5 were isolated from xj for the first time. The minimum inhibitory concentration (MIC) of five compounds against three plant pathogens was evaluated, the results showed that compound 4 exhibited the strongest antibacterial activity against tested bacteria, and RS-2 was the most sensitive to compound 4, showing the lowest MIC of 15.56 μg/ml. We concluded that the mechanism of action of the compound 4 against RS-2 might be described as compound 4 acting on bacterial protein synthesis and intracellular metabolism according to the results of the scanning electron microscopy observation, permeability of cell membrane and SDS-PAGE. These results indicated that compound 4 has good potential to be as a biocontrol agent. In conclusion, the results from this study demonstrated that the compounds with antibacterial activity are of great significance of the prevention and control of plant phytopathogenic bacteria, and they may be applicable to exploring alternative approaches to integrated control of phytopathogens.
真菌能产生多种次生代谢产物，它们是新型生物活性化合物的潜在来源。细菌性植物病害对全球农业的可持续发展造成严重影响，因此利用微生物中的天然抗菌化合物来控制植物病原体很有必要。本研究旨在探究xj的生物活性化合物，以三种植物病原体（T - 37、EC - 1和RS - 2）作为指示菌，通过生物活性追踪，从xj孢子粉中分离出五种化合物，并利用核磁共振（氢核磁共振和碳核磁共振）和电子轰击质谱对化合物进行表征，鉴定为麦角固醇（1）、β - 谷甾醇（2）、5 - 十五烷基间苯二酚（3）、5 - 羟甲基 - 2 - 呋喃羧酸（4）和琥珀酰亚胺（5）。化合物3和5首次从xj中分离得到。评估了这五种化合物对三种植物病原体的最低抑菌浓度（MIC），结果表明化合物4对受试细菌表现出最强的抗菌活性，RS - 2对化合物4最敏感，最低MIC为15.56μg/ml。根据扫描电子显微镜观察、细胞膜通透性和十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳结果，我们得出化合物4对RS - 2的作用机制可能是作用于细菌蛋白质合成和细胞内代谢。这些结果表明化合物4有作为生物防治剂的良好潜力。总之，本研究结果表明具有抗菌活性的化合物对植物植物病原菌的防治具有重要意义，它们可能适用于探索植物病原体综合防治的替代方法。
