摘要
从新疆地区土壤中经驯化、分离纯化得到一株极端嗜盐菌,并对其形态特征、生理生化特性及16S rDNA同源性进行了检索比较,鉴定该菌株为伸长盐单胞菌(Halomonas elogata);其次,考察了不同因素对菌株降解偶氮染料--活性兰BRF的影响,比较了不同盐度条件下的降解率,并在30℃、5%盐度生长条件下采用单因素实验考察了该菌接菌量、染料初始浓度、初始pH等因素对活性兰BRF72h降解率的影响,采用正交试验L9(33)获得适宜的降解条件;最后,通过紫外-可见吸收光谱分析了降解产物.结果表明,该菌株耐盐范围为0～32%,最适生长盐度为5%～20%;在盐度为3%～25%条件下该菌株对活性兰BRF的降解率随着盐度的升高先升后降,5%盐度下的降解效果最佳;在30℃、5%盐度下适宜降解条件为:染料浓度100mg·L-1,pH=7,接菌量5%,72h的降解率为88.62%.紫外-可见光谱结果显示,降解产物的光谱与活性兰BRF的明显不同,可见光区的吸收峰消失,正己烷萃取液无紫外吸收,二氯甲烷萃取液出现两个紫外吸收峰,推测为芳胺类及杂环类等极性化合物;质谱分析证实,降解产物合苯甲基二胺、2,6-氨基苯酚等极性化合物.
An extremely halophilic bacterial strain was acclimated,isolated and purified from the saline-alkali soil obtained from the Xinjiang Uygur Autonomous Region.It was identified as Halomonas elogata based on its morphology,physiological-biochemical characteristics and 16S rDNA sequence analysis.Subsequently,the influencing factors on the azo dye degradation were explored.Degradation effects in a series of salt concentrations were compared.In single factor experiments,the influencing factors of inoculation volume,initial azo dye concentration and pH were tested respectively under inoculation conditions of 30℃ and 5% salinity.The orthogonal experiments L9（33） were designed to obtain the optimal experiment conditions.Finally,the degradation products were estimated by the UV-vis spectra.The results indicated that the strain Halomonas elogata was tolerant to a wide salinity ranging from 0 to 32%,while the optimal salinity for its cell growth was from 5% to 20%.Among salinity range of 3% to 25%,the degradation rate increased initially and then decreased with the salinity increasing,and the best degradation effect happened when the salinity was 5%.At 30℃ and salinity of 5%,the optimal conditions for degradation of azo dye Reactive Blue BRF were found as follows：initial concentration of 100 mg · L-1 for azo dye,pH 7 and initial inoculation volume of 5% for the strain.Under these conditions,an 88.62% degradation of azo dye was achieved over a time period of 72 hours.The UV-vis spectra revealed that the degradation products were quite different from Reactive Blue BRF.There was no peak in visible region and its n-hexane extraction,while its dichloromethane extracts exhibited two UV absorption peaks implying that degradation products might be polar aromatic amines and heterocyclic compounds.Mass spectrometry results revealed that the degradation products included polar compounds such as benzyl diamine and 2,6-diamino-phenol.
出处
《环境科学学报》
CAS
CSCD
北大核心
2012年第9期2091-2096,共6页
Acta Scientiae Circumstantiae
作者简介
作者简介：韦娜（1986-），女，E-mail：weina333aaa@163．com；
通讯作者（责任作者），E-mail：qqzhang@onc．edu．cn.
