Abstract：
Rice sheath blight, caused by the fungus Rhizoctonia solani, poses a significant threat to rice cultivation globally. This study aimed to investigate the potential mechanisms of action of camphor derivatives against R. solani. Compound 4o exhibited superior fungicidal activities in vitro (EC50 = 6.16 mg/L), and in vivo curative effects (77.5%) at 500 mg/L were significantly (P < 0.01) higher than the positive control validamycin·bacillus (66.1%). Additionally, compound 4o exhibited low cytotoxicity and acute oral toxicity for adult worker honeybees of Apis mellifera L. Mechanistically, compound 4o disrupted mycelial morphology and microstructure, increased cell membrane permeability, and inhibited both PDH and SDH enzyme activities. Molecular docking and molecular dynamics analyses indicated a tight interaction of compound 4o with PDH and SDH active sites. In summary, compound 4o exhibited substantial antifungal efficacy against R. solani, serving as a promising lead compound for further optimization of antifungal agents.
摘要：
水稻纹枯病,由真菌枯萎病引起，对全球水稻种植构成重大威胁。本研究旨在探讨樟脑衍生物对索兰尼的潜在作用机制。化合物4o在体外表现出优异的杀菌活性(EC50=6.16mg/L),500mg/L的体内疗效（77.5％）显着（P<0.01）高于阳性对照有效的霉素·杆菌（66.1％）。此外,化合物4o对ApismelliferaL.的成年工蜜蜂具有低细胞毒性和急性口服毒性。化合物4o破坏菌丝体形态和微观结构，细胞膜通透性增加，并抑制PDH和SDH酶活性。分子对接和分子动力学分析表明化合物4o与PDH和SDH活性位点的紧密相互作用。总之,化合物4o表现出对R.solani的实质性抗真菌功效，作为进一步优化抗真菌药物的有前途的先导化合物。
