表面活性剂对热带假丝酵母降解十六烷的影响

研究了Triton X-100、鼠李糖脂二糖脂(di-RL)和CTAB等3种表面活性剂对1株热带假丝酵母菌株Candida tropicalis降解十六烷的影响.结果表明,低浓度的Triton X-100对菌的生长及其十六烷的降解无明显影响,而高浓度的Triton X-100则抑制菌的生长及其对十六烷的降解,96h后Triton X-100浓度分别为0, 0.1, 0.3, 0.5, 1.0和3.0CMC时,对应的十六烷的平均残留率分别为20.5%, 20.2%, 22.0%, 54.4%, 71.2%和68.8%.di-RL促进菌的生长及十六烷的降解,且促进作用随着di-RL浓度的增加而增大,96h后浓度为0.1, 0.3, 0.5, 1.0和3.0CMC的di-RL分别促使十六烷的平均残留率降低到17.4%, 16.6%, 9.9%, 8.8%和7.8%;di-RL在发酵过程中被降解,且添加的di-RL的浓度越大,其被降解的比例越大.CTAB完全抑制菌体的生长和十六烷的降解,表明其具有毒性作用.

Effects of surfactants on biodegradation of hexadecane by Candida tropicalis

The effects of three kinds of surfactants (Triton X-100, di-RL, CTAB) on hexadecane degradation by Candida tropicalis CICC 1463 were studied. Triton X-100 with low concentrations had little effects on cell growth and hexadecane degradation, but had inhibitive effects at high concentrations. After 96 hours, average residual rate of hexadecane was 20.5%, 20.2%, 22.0%, 54.4%, 71.2% and 68.8% for the Triton X-100 concentration of 0, 0.1, 0.3, 0.5, 1.0 and 3.0CMC, respectively. di-RL increasingly enhanced cell growth and hexadecane degradation with concentration increasing, and average residual rate of hexadecane decreased to 17.4%, 16.6%, 9.9%, 8.8% and 7.8% for the concentration 0.1, 0.3, 0.5, 1.0 and 3.0CMC of di-RL after 96 hours. di-RL was also degraded in the fermentation process, and the degradation rate increased with increasing di-RL concentration. CTAB completely inhibited cell growth and hexadecane degradation, indicating its toxicity to Candida tropicalis CICC 1463.