中文摘要：

通过分离、初筛和复筛从盐渍化石油污染土壤中分离出一株高效耐盐的石油降解菌株YJ-8,经形态学、生理生化和16S rRNA序列分析,该菌株被鉴定为粘质沙雷氏菌Serratia marcescens,其石油烃的降解率为64%。耐盐性实验结果表明,该菌可在NaCl浓度为50 g/L的培养基中生长。为进一步增强该菌株耐受高浓度NaCl和降解石油烃的能力,采用低能N^＋注入技术对其进行诱变,最终获得1株遗传性能稳定的突变株。该突变株在原油发酵液中可将表面张力降至27.5 mN/m,石油烃的降解效率为74%,可耐受80 g/L浓度的NaCl。作为一株耐盐的石油烃高效降解菌,该菌在石油污染的盐渍化土壤修复中具有广阔的应用前景。

英文摘要：

A halo-tolerant strain YJ8,which can degrade petroleum efficiently,was isolated from saline soil contaminated by petroleum and selected out by enrichment culture,prescreening and rescreening. Through morphological,physiological,biological,and phylogenetic（16S rRNA） characterization,the strain YJ8 with the petroleum-degrading rate of 64%,was identified as Serratia marcescens,it could endure NaCl concentration of 50 g/L. In order to enhance its petroleum-degrading and halo-tolerant ability,the mutation of YJ8 was carried out by using low energy N~＋ implantation. After the mutation,the mutant YJ8-10,which showed the highest petroleum-degrading rate and stable hereditary stability was selected out. In the crude oil broth,the mutant YJ8-10,with the petroleum-degrading rate of 74%,could reduce the liquid surface tension to 27.5 mN/m,and endure NaCl concentration up to 80 g/L. Therefore,the halo-tolerant and high-petroleum-degrading bacteria YJ8-10 will have a broad application prospects in petroleum-contaminating saline soil restoration.