School of Life Science and Agriculture, Qiannan Normal University for Nationalities, Duyun, Guizhou, 558000, China.
Chem Biodivers. 2024 May;21(5):e202400337. doi: 10.1002/cbdv.202400337. Epub 2024 Apr 11.
Rice sheath blight (RSB), caused by Rhizoctonia solani, is a significant disease of rice. The negative effects of chemical fungicides have created an urgent need for low-toxicity botanical fungicides. Our previous research revealed that the ethanol crude extract of Moutan Cortex (MC) exhibited superior antifungal activity against R. solani at 1000 μg/mL, resulting in a 100 % inhibition rate. The antifungal properties were mainly found in the petroleum ether extract. However, the active ingredients of the extract are still unclear. In this study, gas chromatography-mass spectrometry (GC-MS) was utilised for the analysis of its chemical components. The mycelium growth rate method was utilized to detect the antifungal activity. The findings indicated that paeonol constituted the primary active component, with a content of more than 96 %. Meanwhile, paeonol was the most significant antifungal active ingredient, the antifungal activity of paeonol (EC=44.83 μg/mL) was much higher than that of β-sitosterol and ethyl propionate against R. solani. Observation under an optical microscope revealed that paeonol resulted in abnormal mycelial morphology. This study provided theoretical support for identifying monomer antifungal compounds and developing biological fungicides for R. solani.
水稻纹枯病（RSB）由立枯丝核菌引起，是一种严重影响水稻的疾病。化学杀菌剂的负面影响促使人们迫切需要低毒性的植物源杀菌剂。我们之前的研究表明，牡丹皮乙醇粗提物在 1000μg/mL 时对丝核菌表现出优异的抗真菌活性，抑制率达到 100%。抗真菌特性主要存在于石油醚提取物中。然而，提取物的活性成分仍不清楚。在这项研究中，采用气相色谱-质谱联用（GC-MS）分析其化学成分。利用菌丝生长速率法检测抗真菌活性。结果表明，丹皮酚是主要的活性成分，含量超过 96%。同时，丹皮酚是最主要的抗真菌活性成分，其抗真菌活性（EC=44.83μg/mL）明显高于β-谷甾醇和丙酸乙酯对丝核菌的抗真菌活性。光学显微镜观察发现，丹皮酚导致菌丝形态异常。这项研究为鉴定单体抗真菌化合物和开发防治丝核菌的生物杀菌剂提供了理论支持。
