利用卷枝毛霉成球特性高效收获微藻  

Highly Efficient Bioflocculation of Microalgae Using Mucor circinelloides

作　　者：顾琼[1] 金文标[1] 陈远清[1] 郭仕达[1] 万超凡 

机构地区：[1]哈尔滨工业大学深圳研究生院,土木与环境工程学院,深圳518055

出　　处：《环境科学》2017年第2期688-696,共9页Environmental Science

基　　金：深圳市科技创新委员会项目(JCYJ20150529114024234)

摘　　要：利用卷枝毛霉孢子悬液与小球藻共培养,用过滤含藻菌球的方式来收获微藻.以人工配水为培养基,收获效率为指标,通过单因子试验和正交试验得到最佳收获条件为:pH=6.0,葡萄糖质量浓度为1.25 g·L^(-1),菌藻比为1∶250,收获效率为91.08%.对培养前后培养液中多糖质量浓度进行测定,发现小球藻在培养48 h后多糖质量浓度较培养前增加了约0.047g·L^(-1),而菌藻共培养后的混合液中多糖质量浓度为0.019 g·L^(-1).由此可知在菌藻共培养过程中,小球藻会向外分泌某些水溶性多糖物质供卷枝毛霉利用,二者有一定的共生作用.对小球藻和卷枝毛霉细胞表面Zeta电位进行测量发现,小球藻细胞表面的Zeta电位值随着藻液pH值变化波动不大;而卷枝毛霉细胞表面的Zeta电位值,随着pH值的变小,电位值可由原先最低的-37.7 m V升至-9.87 m V.由此推定菌藻相互吸附的主要机制为电中和吸附.Harvesting of microalgae is the major challenge in cost-efficient large-scale microalgal biomass production due to their low concentration and small cell size in the culture medium. The present paper aimed to study the efficiency of the filamentous fungus Mucor circinelloides spores suspensions to harvest the green unicellular microalga Chlorella pyrenoidosa grown in synthetic medium. Results showed that the optimal co-culture conditions were pH = 6. 0, 1. 25 g·L^ - 1 glucose and 1： 250 fungi to microalgae ratio with harvest efficiency of 91. 08% . In addition, the mentioned optimal conditions could be applied for actual sewage with harvest efficiency of 92. 33% . Polysaccharide concentrations measured before and after 48 h of cultivation showed that the polysaccharide of C. pyrenoidosa cultured alone was increased by 0. 047 g·L ^- 1 , while co-cultured mixture showed increase in polysaccharides by 0. 019 g·L ^- 1 . The recorded decrease in polysaccharides concentration in the co-culture might be attributed to using of excreted polysaccharides by M. circinelloides to grow, confirming the symbiotic association of both organisms. Furthermore, with decreasing the pH, C. pyrenoidosa Zeta potential was stable, while it was increased from - 37. 7 mⅤ to - 9. 87 mⅤ in M. circinelloides, which indicated that charge neutralization was the mechanism of flocculation between algae and fungi.

关 键 词：微藻 丝状真菌 卷枝毛霉 收获 机制 

分 类 号：X703.1[环境科学与工程—环境工程]