以枇杷炭疽病菌为靶标菌,测定了凤尾菇发酵液的乙酸乙酯和正丁醇萃取物的抑菌作用,对抑菌活性较强的乙酸乙酯萃取物采用硅胶柱和Sephadex LH-20凝胶柱进行分离.结果表明,经硅胶柱分离后获得5个组分,其中F4组分对枇杷炭疽病菌有较强的抑菌活性,F4组分再经Sephadex LH-20凝胶柱进一步分离获得3个组分,其中F4-A组分对枇杷炭疽病菌抑菌活性最强.电镜观察结果显示,经F4-A组分处理后的枇杷炭疽病菌菌丝呈不规则的肿大和缢缩,菌丝细胞壁不规则增厚,细胞原生质不均匀,有较大的空腔形成,囊泡增多,这些变化最终导致菌丝细胞解体死亡.
The antifungal activity of the ethyl acetate and n-butanol extracts of fermentation broth of Pleurotus sajor-caju was tested with an indicator fungus, Colletotrichum gloeosporioides, and stronger activity was found in ethyl acetate extract.Five fractions were isolated from ethyl acetate extract through silica gel column chromatography and tested for indicator fungus.One fraction of F4 with maximum inhibiton activity among the five fractions was further isolated with sephadex LH-20 gel chromatography and three components, F4-A, F4-B and F4-C were obtained, respectively.The component F4-A could inhibit remarkably the growth of C.gloeosporioides and the EC50 to hyphal growth and spore germination were 0.12 mg·mL^-1and 0.32 mg·mL^-1, respectively.The inhibition activity of the component F4-A to the hyphae of C.gloeosporioides was observed under a scanning electron microscope(SEM) and a transmission electron microscope(TEM), respectively.The results revealed that the component F4-A not only could inhibit hyphal growth of C.gloeosporioides, but also cause a series of marked morphological and structural alterations of hyphae, including irregular swelling, constriction of the hyphae, considerable thickening of the hyphal cell walls, uneven cell protoplasm, the formation of a large cavity, vesicles increasion in the hyphal cell, etc.These negative effects of the component F4-A resulted in the hyphal cell necrosis of C.gloeosporioides in the end.
Journal of Fujian Normal University:Natural Science Edition
Pleurotus sajor-caju fermentation broth
column chromatography isolation