茼蒿中绿原酸抑制西瓜枯萎病菌活性研究

Antifungal Activity of Chlorogenic Acid From Chrysanthemum coronarium L. on Fusarium oxysporum f. sp. niveum

为了确定茼蒿中抑制西瓜枯萎病菌的物质,以西瓜枯萎病菌为指示菌株,对从茼蒿茎叶组织中分离纯化并鉴定出的3-O-咖啡酰奎宁酸(绿原酸)的离体抑菌活性进行了研究。结果表明,绿原酸对西瓜枯萎病菌的最不抑菌浓度(MIC)和最不杀菌浓度(MFC)分别为31.25和125 mg·m L^(-1),经室内毒力测定,其对西瓜枯萎病菌的凌半最大效应浓度(EC50)为53.05 mg·m L^(-1)。在绿原酸浓度分别为31.25、125、53.05 mg·m L^(-1)时,即MIC、EC_(50)、MFC的绿原酸浓度处理下,西瓜枯萎病菌的孢子萌发率分别为64%、33%、12%,而绿原酸浓度为0时的孢子萌发率则达到92%,经邓肯氏差异分析,各处理间孢子萌发率差异均显著。随着绿原酸浓度的增大,西瓜枯萎病菌的菌丝干、鲜重均呈现出下降的趋势。此外,绿原酸处理能使细胞膜通透性增加,从而导致菌体细胞内电解质外渗速度加快。本研究结果为茼蒿的深度开发和利用提供了科学依据,也为其他天然抑菌活性成分的筛选及抑菌机理的研究提供可行的试验方法和理论依据,对研究和开发新的天然植物源杀菌剂具有重要的学术价值和应用前景。

In order to determine the antibiotics on Fusarium oxysporum f. sp. from Chrysanthemum coronarium L.,we studied the bacteriostatic activity of 3-O-caffeoylquinic acid（ chlorogenic acid） which was isolated from the stem and leaf tissues of Chrysanthemum. The MIC and MFC of F. oxysporum f. sp. were 31. 25 mg·m L^-1 and 125 mg·m L^-1 respectively. The EC_（50） of chlorogenic acid to F. oxysporum f. sp. was 53. 05 mg·m L^-1 by indoor virulence assay. The spore germination rates of watermelon F. oxysporum f. sp. were 64%,33% and 12% at the concentrations of 31. 25、125、53. 05 mg·m L^-1,respectively,while the spore germination rate reached to 92% at the concentration of 0,the difference of spore germination rate between treatments was significant by Duncan＇ s difference analysis. With the increase of pharmacy concentration,the hyphae and fresh weight of F. oxysporum f. sp. showed a decreasing trend. In addition,the treatment of the agent increased the cell membrane permeability and accelerated the rate of infiltration of the inner electrolyte. This research can provide scientific basis for further development and utilization of Chrysanthemum,and a feasible experimental method and theoretical basis for the screening of other natural antibacterial active ingredients and the study of the mechanism of bacteriostasis,which has important academic value and application prospect for research and development of new natural plant source fungicides.