耐盐反硝化细菌的筛选鉴定及生长促进剂对其反硝化性能的影响研究

Screening and Identification of Salt-Resistant Denitrifying Bacterium and Effect of Growth Promoters on Its Denitrification Performance

生物脱氮是高效、低成本的废水处理方式,生长促进剂可以调控微生物的代谢。从海州湾的海泥样品中分离得到1株耐盐反硝化细菌LY,研究了其反硝化性能,并比较了4种生长促进剂赤霉素、复硝酚钠、萘乙酸、胺鲜脂等对菌株LY反硝化性能的影响。结果表明,根据形态特征、生理生化性质及16S rDNA基因序列,鉴定该菌为解淀粉盐水球菌(Salinicoccus amylolyticus);在反硝化培养基中菌株LY表现出良好的反硝化性能,72 h脱氮率为80.83%;萘乙酸、胺鲜脂对菌株LY的生长具有促进作用,赤霉素、复硝酚钠对菌株LY的生长略微抑制;萘乙酸能够显著提高菌株LY的脱氮效率,脱氮率提高了57.8%,添加0.01 mg·L^(-1)萘乙酸后,菌株LY可以在24 h内将硝酸盐完全转化;添加1 mg·L^(-1)萘乙酸后,菌株LY对废水COD的去除效率显著提高。表明,菌株LY和生长促进剂萘乙酸在高盐高氮废水处理中具有潜在应用前景。

Biological nitrogen-removal is an efficient and low-cost wastewater treatment method,and growth promoters can regulate the microbial metabolism.In this paper,we isolated a salt-resistant denitrifying strain LY from sea mud samples in Haizhou Bay,and studied its denitrification performance.Meanwhile,we compared the effects of four growth promoters,including Gibberellin,sodium nitrophenolate,naphthalene acetic acid,and amine fresh fat,on the denitrification performance of strain LY.The results show that the strain LY is identified as Salinicoccus amylolyticus based on morphological characteristics,physiological and biochemical properties,and 16S rDNA gene sequence.The strain LY has good denitrification performance in denitrification medium,and the denitrification rate can reach 80.83%at 72 h.Naphthalene acetic acid and amine fresh fat have a promoting effect on the growth of strain LY,while Gibberellin and sodium nitrophenolate slightly inhibit the growth of strain LY.Naphthalene acetic acid can significantly improve the nitrogen-removal efficiency of strain LY,and the nitrogen-removal rate increases by 57.8%.After adding 0.01 mg·L^(-1) naphthalene acetic acid,the strain LY can completely transform nitrate within 24 h.In addition,after adding 1 mg·L^(-1) naphthalene acetic acid,the COD removal efficiency of strain LY from wastewater is significantly improved.The study indicates that the strain LY and the growth promoter naphthalene acetic acid have promising applications in the treatment of high-salt and high-nitrogen wastewater.