桂花树内生真菌的分离及其抗氧化抑菌活性

摘要

采用组织贴片培养分离法，分别从桂花树的花、叶、枝等健康组织中分离、纯化获得14、38和22株内生真菌，并采用总抗氧化性能测定、DPPH自由基清除实验和滤纸片法对74株内生真菌抗氧化活性、抑菌活性进行了筛选。结果表明：从桂花中分离获得的内生真菌GH05发酵液的乙酸乙酯萃取液具有较强的抗氧化活性和抑菌活性，其中发酵原液的等量乙酸乙酯萃取液总抗氧化性能达129.04μg Vc/mL，对DPPH自由基清除率为90.35％，5倍浓缩的乙酸乙酯萃取液对大肠杆菌、金黄色葡萄球菌、蜡状芽孢杆菌、苏云金芽孢杆菌和枯草芽孢杆菌等细菌的抑菌圈直径分别可达13.3、19.3、12.4、14.6和14.4 mm。形态学和分子生物学鉴定结果表明GH05为球毛壳菌。%In the cultural method of plant tissue paster on solid medium,14,38 and 22 strains of endophytic fungi were isolateded from fine tissue of Osmanthus fragrans Lour.flowers,leaves and branches.The antioxi-dant and antibacterial activities of the broth of the 74 strains were studied by vitro methods.The results showed that GH05,one strain isolated from Osmanthus fragrans Lour.flowers,has strong antioxidant activities and antibacterial activities.The total antioxidant capacity and the scavenging rate on DPPH of the acetic ether ex-tract of GH05 broth were 129.04 μg Vc/mL and 90.35%.The acetic ether extract of broth of strain GH05 could inhibit the growth of Escherichia coli,Staphylococcus aureus,Bacillus cereus,Bacillus thuringiensis and Bacillus subtilis with the diameters of inhibition zone of 13.3,19.3,12.4,14.6 and 14.4 mm,respectively. The strain GH05 was identified as Chaetomium globosum by morphological and molecular biological method.