一株高效降解正丙醇的放线菌的筛选与鉴定

Isolation and Identification of an N-Propanol Degrading Actinomycete Strain

以正丙醇为唯一碳源的选择培养基,采用梯度稀释法与平板划线等筛选方法,从浓香型窖底泥中分离、筛选降解正丙醇性能优良的菌株,并对筛选的优良菌株采用形态学及16S r DNA分子生物学进行鉴定,并对菌株的发酵参数进行了研究。共分离到具有正丙醇降解能力的菌株10株,经正丙醇降解能力筛选,发现分离的MBM-7对正丙醇的降解能力较强。经形态特征和16S r DNA基因序列分析,鉴定菌株MBM-7为放线菌目中的原玻璃蝇节杆菌(Arthrobacter protophormiae)。通过温度、正丙醇含量和pH值等发酵参数的研究表明,该菌的最适降解条件为:培养温度32℃、初始正丙醇浓度0.1%、pH7;在上述优化条件下发酵15 d,正丙醇降解率达到91.2%。该菌为首次从窖泥中分离到降解正丙醇的放线菌。

Adopting culture media with n-propanol as the only carbon source,strains with high n-propanol degrading performance were isolated and screened out from Nongxiang pit mud by using gradient dilution method and plate streaking method.Then morphological analysis and16S rDNA identification were carried out,and the fermentation parameters of the strains were studied.A total of10n-propanol degrading strains were isolated,among which strain MBM-7had relatively high n-propanol degrading performance,and it was identified as Arthrobacter protophormiae.The optimum operation conditions of strain MBM-7were obtained as follows:32℃,initial n-propanol concentration at0.1%,pH=7.Fermenting for15d under the above conditions,the degradation rate of n-propanol could reach up to91.2%.This strain was the first n-propanol degrading actinomycete strain isolated from pit mud.(Trans.by HUANG Xiaoli)