核桃青皮提取物的抑真菌活性研究

Anti-fungal Activity of Walnut Green Husk Extracts

核桃青皮中含有种类较为丰富对供试真菌具有抑菌活性的次生代谢物质。以核桃青皮为原料,乙醇、石油醚、正丁醇、乙酸乙酯以作为提取剂进行浸提,得到核桃青皮的提取液,选取酵母菌、青霉、木霉、马拉色菌、脚气真菌作为供试菌种,通过实验观察不同溶剂提取液对供试菌种的抑制作用,研究核桃青皮提取物对真菌的抑制作用。核桃青皮中含有胡桃醌、多糖、黄酮等多种活性成分,利用分光光度法测定黄酮、胡桃醌、多糖的吸光值,通过吸光值计算提取物中各成分的质量浓度。结果表明:核桃青皮不同极性溶剂的浸提液对酵母菌、青霉、木霉均有抑制效果。核桃青皮95%乙醇浸提液对脚气真菌的抑制效果显著,抑菌率为59.64%;正丁醇核桃青皮浸提液对脚气真菌、马拉色菌有抑制效果。通过核桃青皮不同极性溶剂浸提液抑菌率的比较,和核桃青皮中所含三种活性物质的浓度与抑菌机制可知,核桃青皮不同极性溶剂的浸提液中主要起抑菌作用的是胡桃醌。

Walnut green husk contains abundant types of secondary metabolites with antibacterial activity against fungi. Using walnut green husk as raw materials and organic solvent （ethanol, petroleum ether, butanol or ethyl acetate） as extraction regent, walnut green husk extracts was obtained and their inhibition effect on selected yeasts （Penicillium, Trichoderma, Malassezia and athlete＇s foot fungus） were investigated. Results showed that walnut green husk contained several kinds of active ingredients, such as juglone, polysaccharides and flavonoids.The concenWation of each component in the extract was determined by spectrophotometer. Walnut green husk extracts by different solvents showed inhibitory effect on yeast, Penicillium and Trichoderma. Ethanol （95%） extracts of walnut green husk had significant inhibitory effect on athlete＇s foot fungus with inhibitory rate being of 59.64%. Butanol walnut green husk extract had inhibitory effects on the athlete＇s foot fungus and Malassezia. Comparative analysis of the anti-fungal activity and concentrations of active substances in walnut green husk extracts showed that juglone was the main active components in walnut green husk extracts.