4种绿僵菌乙酸乙酯初提物抗菌活性比较

Comparison of Antimicrobial Activities of Ethyl Ecetate Extracts from Four Metarhizium spp.

绿僵菌属真菌是一种具有很强致病性的昆虫病原真菌,广泛地寄生于多种昆虫体内。以冬虫夏草、蛹虫草为代表的昆虫病原真菌具有良好的医药保健功能,绿僵菌能产生多种具有活性的代谢产物。本研究采用液体深层培养技术,对4种绿僵菌菌丝体进行液体培养,培养液经乙酸乙酯萃取后获得绿僵菌初提物。采用抑菌圈法评价4种绿僵菌乙酸乙酯初提物对13种致病菌的抗菌活性,并测定对相应致病菌的最低抑制浓度。结果表明,经液体培养后的4种绿僵菌乙酸乙酯初提物均具有一定的抗菌活性。4种绿僵菌提取物均对蜡样芽孢杆菌和缓慢芽孢杆菌具有抑制作用,其中贵州绿僵菌提取物对蜡样芽胞杆菌的最低抑菌浓度达到6.45mg/m L,对溶血性葡萄球菌的最低抑菌浓度为3.23mg/m L。棕色绿僵菌初提物均对蜡样芽孢杆菌、缓慢芽孢杆菌、溶血性葡萄球菌、副溶血性弧菌、藤黄微球菌产生抑制效果,对藤黄微球菌的最低抑菌浓度达到13.9mg/m L。本研究为虫草绿僵菌抗菌化合物的进一步研究及开发利用奠定基础。

Metarhizium spp.are highly pathogenic insect fungi,which widely parasitize in a variety of insects.The insect pathogenic fungi from Cordyceps sinensis and Cordyceps militaris have a good medical and health functions,which can produce variety of active metabolites.In this study,four species of Metarhizium were cultured in liquid culture.The culture medium was extracted with ethyl acetate,which finally obtain the primary extract of Metarhizium spp..The antimicrobial activities of the four ethyl acetate extracts of Metarhizium spp.to 13 pathogens were evaluated using the inhibition zone method,and the minimum inhibitory concentration(MIC)of the corresponding pathogens was determined.The results showed that the ethyl acetate extracts produced by the four species of Metarhizium had a certain antibacterial activity.Four extracts of Metarhizium spp.had inhibitory effects on Bacillus cereus and Bacillus lentus.The minimum inhibitory concentration of the extract of Metarhizium guizhouense on Bacillus cereus was 6.45 mg/mL,and the MIC for Straphylococcus haemolyticus was 3.23 mg/mL.The extracts of Metarhizium brunneum had inhibitory effect on the Bacillus cereus,Bacillus lentus,Vibrio parahaemolyticus,Straphylococcus haemolyticus and Micrococcus luteus.The minimum inhibitory concentration of Metarhizium brunneum extract on Micrococcus luteus was 13.9 mg/mL.This study laid the foundation for the further study,and for development and utilization of antimicrobial compounds of Metarhizium spp.