Mutation Breeding Of Chlorella Vulgaris By UV And ARTP And Construction Of Symbiotic System Of Algae And Bacteria

Microalgae treatment of domestic wastewater can effectively absorb nutrients,decompose toxic pollutants,enrich heavy metal ions,improve water dissolved oxygen,enhance n,P and other elements circulation.However,there are also bottlenecks such as long processing time and low microalgae yield.The symbiotic system of microalgae and composite bacteria can solve the problems of slow growth of microalgae and difficult utilization of macromolecular nutrients.In order to improve the efficiency of microalgae in wastewater treatment and algae biomass in Hebei Province,this paper studies the selection of algae species in the south central region of Hebei Province,and the treatment of Chlorella by UV mutagenesis and atmospheric pressure room temperature plasma mutagenesis The removal effect of TN,TP and COD by Chlorella colony and complex bacteria treated by mutation technology was discussed,which laid the theoretical foundation and technical guidance for the coupling of industrial treatment of domestic wastewater and Chlorella production,and also provided some new ideas and new directions for wastewater treatment.1.In order to obtain microalgae species suitable for the local environment,six species were selected from the south central area of Hebei Province.The growth rate,cell density,biomass accumulation and other indicators were measured.WS-4 strain(Chlorella vulgaris)was selected as the following experimental species after optimization and comparison.2.Two mutants nby-1 and nby-2 were obtained by UV irradiation.The biomass accumulation,Chl.A,crude protein,total lipid and polysaccharide of the mutants were measured.The growth rate of nby-1 increased by 6.95%,biomass increased by 7.38%,chlorophyll content increased by 14.54%,and crude protein content decreased The content of total fat increased by 9.81%.3.The mutant nby-1 of Chlorella vulgaris was treated by ARTP mutation technology,and the mutation time was 40 s.By calculating the growth rate and measuring the biomass accumulation,a chlorella mutant byq-1 was selected from 10 positive mutants.Its biomass accumulation increased by 13.24%,Chl.A content was 7.6mg/l,crude protein content was 31.54%,polysaccharide content was 1.67%,and total fat content was 25.75%.4.The symbiotic system of Chlorella and composite bacteria was constructed.The results showed that the removal rates of TN,TP and COD in the mixed medium were 79.16%,75.84% and 81.79%,respectively.The biomass,chlorophyll and total lipid contents of Chlorella in symbiotic system were 0.936g/l,7.81mg/l and 28.79% respectively,which increased by 14.43%,10.15% and 6.35% respectively.