【摘要】 通过稀释涂板法和划线法,从河道污泥、花园土壤、鲈鱼肠道内分离筛选到5株产絮凝剂细菌,经过复筛,得到一株高效产絮凝剂菌株DK-1。其适宜培养条件为:乳糖20 g/L,尿素0.5 g/L,酵母膏0.5 g/L,K2HPO45 g/L,KH2PO42 g/L,NaCl 0.1 g/L,(NH4)2SO40.2 g/L,琼脂15~20 g,双蒸水1000 mL,pH值为7.5~9.5,装液量30~60mL/250 mL,摇床转速160 r/min,37℃培养48~72 h。其发酵液对高岭土悬液的絮凝率高于80%。该菌在3%~5%接种量条件下可获得最短2天的高效产絮凝剂周期,絮凝成分以多糖和蛋白质为主且具有较好的热稳定性,结果表明该菌具有重要的研究前景和应用价值。更多还原

【Abstract】 Five stubs of strains were sorted out and dissolved from the sludge,the intestines of weever and the garden soil.A strain,DK-1,with high flocculating activity was futher screened from thses strains.The results showed that the optimum cultivation condition is carbon sources(lactose) 20 g/L,and nitrogen sources-the mixture of yeast extract(0.5 g/L) and ammonium sulfate(0.2 g/L) and carbamide(0.5 g/L).Under the cultivating conditions of primary pH value 7.5～9.5,the liquid pack of 30～60 mL/250 mL inoculum size being 3%～6%,temperature 37 ℃,and a shaking table of 160 r/min,strain DK-1 cultivated for 48～72 h can produce a highly efficient flocculant,with the ratio of flocculation to kaolin clay suspension more than 80%.The flocculant mainly includes polysaccharide and a little protein.All the above characteristics will significantly contribute to its broad prosepective industrial applications.更多还原