摘要
从活性污泥中分离得到两株高效的微生物絮凝剂产生菌MBP-31和MBG-15。通过培养条件优化,考察各种因素,如碳源、氮源、pH值、碳氮比、培养时间、絮凝剂投加量对絮凝效果的影响。结果表明,MBP-31对高岭土悬浊液的最佳絮凝条件为:碳源为葡萄糖,氮源为尿素,pH值为7.0～8.0,碳氮比为25,培养时间为48 h,絮凝剂投加量为1 mL。MBG-15对高岭土悬浊液的最佳絮凝条件为:碳源为葡萄糖,氮源为蛋白胨,pH值为7.0～8.0,碳氮比为25,培养时间为96 h,絮凝剂投加量为2 mL。在最佳絮凝条件下进行絮凝试验,MBP-31、MBG-15对高岭土悬浊液的絮凝率分别达到89.87%、91.25%。对两菌株所产微生物絮凝剂的活性分布、热稳定性进行了研究,两种微生物絮凝剂均分布在发酵液离心后的上清液中,MBG-15有较好的热稳定性。
Biopolyrner floccu｜ation is a dynamic process resulting in the formation of stable aggregates or flocculants due to the synthesis of extracellular polymers by living cells. However, the use of biopolymer floeculants has been restricted to some extent for its high cost. In order to obtain effective microbioflocculant and reduee its production costs, two strains of bioflocculant-producing bacteria which both have a good flocculating capability, were screened from activated sludge, named MBP-31 and MBG-15. Then the optimization of influencing factors such as carbon source, nitrogen source, pH value, C/N ratio, culture duration and liquid pack of binflocculant on the cultivation conditions of two strains was studied. The optimum flocculation conditions of MBP-31 are shown as follows： glucose as carbon source, urea as nitrogen source, pH value of 7.0 - 8.0, C/N ratio = 25, 48 hours of culture duration and 1.0 mL of binflocculant. The optimum flocculation conditions of MBG-15 are indicated as follows： glucose as carbon source, peptone as nitrogen source, pH value of 7.0- 8.0, C/N = 25, 96 hours of culture time and 2.0 mL of bioflocculant. Under the optimum conditions, the highest flocculating rate of MBP-31 and MBG-15 could achieve up to 89.87%, 91.25%, respectively. The distribution of flocculating activity and thermal stability were investigated as well. The result showed that most of the microbioflocculants were concentrated in the supernatant and the thermal stability of MBG-15 was considerably high. Thus, in future, both of the studied bioflocculant-producing bacteria strains have a broad prospective applications in wastewater treatment, food and fermetation industries, drinking water treatment and industrial downstream processing. To note, bio-floeculants are harmless to the environment and human beings, indicating their potential to be the alternatives of existing chemical flocculants.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2010年第6期46-49,共4页
Journal of Safety and Environment
基金
温州市科技计划项目(S20090008)
浙江省科技计划项目(2010C3316131)
关键词
环境科学技术基础学科
微生物絮凝剂
筛选
絮凝活性
培养条件
basic discipines of environmental science and technology
microbinflocculant
screening
flocculating activity
culture condition
