以34种植物病原真菌和5种细菌为供试菌,采用离体试验方法对核桃青皮乙醇提取物及其萃取相进行抑菌效果研究。结果表明:核桃青皮乙醇提取物对供试病原真菌均有一定的抑制活性;在浓度为40 mg.mL-1时,乙酸乙酯萃取相抑菌效果最好,对番茄灰霉、棉花立枯和小麦纹枯3种病原真菌的抑制率均为100%,对枯草芽孢杆菌和金黄色葡萄球菌的抑菌圈直径达12.07 mm和12.54 mm;不同浓度乙酸乙酯萃取相对相同病原菌的抑制效果差异显著,对番茄灰霉、棉花立枯、苹果炭疽、小麦纹枯和小麦赤霉5种病原菌的EC50分别为:7.263 4、6.219 1、9.069 5、5.591 2和10.310 2 mg.mL-1。
Antifungal activity of the ethanol extracts and its extract phase from walnut seedcases against 34 species of fungi and 5 microorganisms were studied with the plate diluting method.The results showed that the ethanol extracts of walnut seedcases have different range activities to tested fungus.The inhibitation of acetyl acetate extract is the best when the concentration of every extract phase is 40 mg·mL-1.The inhibiting rates of the extract are 100% to Botrytis cinerea,Thanatephorus cucumeris and Rhizoctonia cerealis,respectively.Diameter of the inhibited rings are 12.07 mm and 12.54 mm to Bacillus subtilis and Staphylococus aureus Rosenbach,respectively.Different concentrations have different antifungal activities to the same pathogenic fungus.Their EC50 values of acetyl acetate's extraction against mycelial growth of Botrytis cinerea Pers,Thanatephorus cucumeris,Glomerella cingnlata.Schr.et,Rhizoctonia cereal and Fusarium graminearum are 7.263 4,6.219 1,9.069 5,5.591 2 and 10.310 2 mg·mL-1,respectively.