伊犁野核桃内抑菌抗氧化内生真菌的分离、筛选和鉴定

Isolation,Screening and Identification of Active Endophytic Fungi from Yili Wild Walnut

旨在从伊犁野核桃中分离抑菌活性、抗氧化性较强的内生真菌,并鉴定其种属。采用组织块分离野核桃内生真菌,通过平板对峙法进行抑菌活性实验,同时检验其 DPPH 自由基清除能力,并对其进行菌种鉴定。结果显示,(1)从野核桃中分离出 49 株内生真菌,茎部数量最多;根部次之,果仁未分离到;(2)菌株 YHT-6 和 YHT-4 抑菌效果显著,对 4 种供试菌株抑菌指数都大于 10,YHT-4 对 4 种供试菌株的抑菌直径均超过 1.4 cm;(3)菌株 YHT-4 清除 DPPH 自由基能力较强,与 Vc 相当;(4)经形态学和分子学初步鉴定菌株 YHT-4 为三线镰刀属(Fusarium tricinctum)。分离得到的菌株 YHT-4 具有较强的抑菌、抗氧化活性,可作为药物开发的潜在来源进行进一步研究。

The objective of this work is to screen the endophytic fungi with strongly antibacterial and antioxidant activities from Yili wild walnut and then identify them. We used tissue separation method to isolate the endophytic fungi from wild walnut,and the plate confrontation to conduct the experiment on their antibacterial activities as well as their DPPH radical scavenging capacity. Finally,the strains were identified. As results,(1)49 strains of endophytic fungi were isolated. The most isolates came from the stem,then from the roots,and none from the kernels.(2)Strain YHT-4 and YHT-6 presented significant antibacterial effects and the inhibitory index was > 10,and YHT-4 inhibited pathogenic fungus with diameter > 1.5 cm.(3)The strain YHT-4 demonstrated a stronger ability to scavenge DPPH free radicals which was equivalent to Vc.(4)The strain YHT-4 was molecularly identified as Fusarium tricinctum based on morphology and molecular science. In conclusion,the isolated strain F. tricinctum sp. YHT-4 had strong antibacterial and anti-oxidant activities,and it can he used as potential sources for drug development in further study.