摘要
于江西省吉安市内一株明万历年间植下的古榕树下,采集根际土样并使用23种指示菌通过管碟法和菌丝生长速率法对土壤内放线菌进行拮抗筛选,最终得到一株传代稳定的广谱拮抗菌株AHF-20.根据对菌株的形态观察、生理生化特性以及分子生物学鉴定,将该拮抗菌株鉴定为链霉菌,并对该菌株的抑菌活性物质进行了研究.结果表明:链霉菌AHF-20的发酵产物对23种测试指示菌全部具有拮抗效果,且抑菌能力稳定性较好,对温度、光照、紫外线、酸碱都有一定的耐受性,于121℃下加热20 min后依然存在抑菌活性.根据活性物质的极性使用正丁醇萃取发酵产物,获得的正丁醇粗提物稀释至1μg·mL^-1后,对大肠杆菌仍有抑制效果,可见具有较好的生防利用潜力和开发成新型微生物药物的可能性.
Rhizosphere soil samples were collected from an ancient banyan tree grown in the Wanli period of Ming Dynasty in Ji’an City,Jiangxi Province.Twenty-three kinds of indicator bacteria were used to screen soil actinomycetes by cylinder-plate method and mycelium growth rate method.A broad-spectrum antagonistic strain AHF-20 with stable passage was obtained.According to the morphological observation,physiological and biochemical tests,and molecular biological identification,the antagonistic strain was identified as Streptomyces.We examined the antibacterial active substance of the strain.The results showed that the fermentation products of Streptomyces AHF-20 had antagonistic effects on all the 23 test indicator bacteria.The antibacterial ability was stable,tolerant to temperature,light,ultraviolet,acid and alkali.Antibacterial activity still existed after heating at 121℃for 20 min.The fermentation product was extracted with n-butanol according to the polarity of the active substance.The obtained crude n-butanol extract was diluted to 1μg·mL^-1,which still had inhibitory effect for Escherichia coli.The results indicated that it has well utilization potential for biocontrol and developing new microbial drug.
作者
李健
李肖鹤
后文
郑沈
朱向东
LI Jian;LI Xiao-he;HOU Wen;ZHENG Shen;ZHU Xiang-dong(College of Biological Science and Engineering,Jiangxi Agricultural University,Nanchang 330045,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2019年第11期3894-3902,共9页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(21366012)
江西省教育厅科技计划项目(GJJ170286)资助~~
关键词
链霉菌
拮抗特性
生物防治
Streptomyces
antagonistic properties
biocontrol
