鼠李糖脂对假单胞菌GP3A降解芘的性能及细胞表面性质的影响

在实验室可控条件下,研究了生物表面活性剂鼠李糖脂对假单胞菌GP3A生长情况、降解芘(初始浓度为15 mg·L-1)性能以及降解过程中菌体表面性质(细胞表面疏水性、菌体Zeta电位)的影响.结果表明,鼠李糖脂明显促进了GP3A的生长,当鼠李糖脂浓度为200 mg·L-1和500 mg·L-1时,72 h时菌体的生长量比未...

Effects of rhamnolipid on the pyrene-degrading ability and cell surface properties of Pseudomonas sp. GP3A

This study aimed to investigate the effects of rhamnolipid on the growth of Pseudomonas sp. GP3A,its pyrene-degrading ablity(the initial pyrene concentration was 15 mg·L^-1) and the cell surface properties including cell surface hydrophobicity and zeta potential of the strain during the degradation process. The results showed that rhamnolipid could obviously promote the growth of GP3A. Compared with the control grown in the absence of rhamnolipid,the biomass of GP3A increased 5 and 12 times in 72h in 200 and 500 mg·L^-1 rhamnolipid,respectively. In addition,the degradation of pyrene was accelerated with increasing rhamnolipid and the average residual rate of pyrene in 144 h decreased to 43%,39%,33%,respectively,for 50,200 and 500 mg·L^-1 of rhamnolipid. The efficiency of pyrene removal was enhanced significantly over that without rhamnolipid,where the residual amount of pyrene was as high as 81%. The cell surface hydrophobicity was enhanced distinctly by rhamnolipid even at the 50 mg·L^-1 low concentration. The cell surface hydrophobicity of GP3A cultivated in 50mg·L^-1 rhamnolipid reached 66% in 72h,while that the control was only 21.1%. Increased cell surface hydrophobicity was beneficial to the degradation of the substrate. The absolute values of zeta potential of the bacteria and the culture medium with pyrene both increased with the addition of rhamnolipid. However,the addition of rhamnolipid had little effect on the zeta potential of the degradation system.