Preliminary study on purification of two microbial contaminated strains of Chlorella
２株污染小球藻的除菌技术

Purification methods of two strains of Chlorella (Chlorella vulgaris and Chlorella pyrenoidosa) contaminated with microbes was studied by investigating sensibility of the two strains to penicillin, streptomycin sulfate and nystatin. The results revealed sensibilities of the two strains of Chlorella to antibiotics were obviously different. There was no great difference of effects between combined and individual utilization of these antibiotics on growth of the two strains. Though combination of these antibiotics could inhibit microbial contaminants temporally in liquid medium, it can not give pure culture. To unite addition of antibiotics and process of centrifuging and washing could remove most bacteria efficiently, but moulds grew up bloomy. It implied there is a complex relationship among Chlorella, contaminative bacteria and moulds in culture media. Finally, pure culture of Chlorella strains were achieved by applying spread plate method twice with combined antibiotics at proper concentration in media.