高效溶磷菌株Bmp5筛选及活力和培养条件的研究

Isolation of the High Efficiency Phosphate Solubilization Bacterium Bmp5 and Its Activity and Culture Conditions

从不同地区的土壤样品中分离出11株微生物菌株，其中菌株Bmp5表现出较高的溶磷活力．对比研究发现，Bmp5对磷酸钙、磷酸铁、卵磷脂的溶解能力明显高于荧光假单胞菌Pseudomonas fluorescens As1．867，对磷酸氢钙的溶磷量是巨大芽孢杆菌Bacillus megaterium As1．223的2．17倍．培养条件优化试验表明，Bmp5的适宜pH范围为5．5～8．0，最适碳源为草酸铵、甘油，最适氮源为草酸铵，最佳培养温度为35℃．金属离子Fe^3＋、Ca^2＋、Mn^2＋、Zn^2＋对Bmp5解磷能力有一定的促进作用，而Cu^2＋、Ni^2＋则抑制其解磷．经鉴定，Bmp5为蜡状芽孢杆菌B．cereus．

Eleven strains of phosphate solubilization microorganisms were isolated from different district soil samples. Among them, Bmp5 showed the highest phosphate solubilizing activity. The phosphate solubilization capacity of Bmp5 in calcium orthophosphate, ferric phosphate and lecithin were significantly higher than that of Pseudomonasfluorescens Asl. 867 ; while the phosphate solubilization capacity in calcium hydrogen phosphate was 1.17 times higher than that of Bacillus megaterium As 1. 223. The optimized culture conditions of the highest phosphate solubilizing acitivity were pH at 5.5-8.0; using ammonium oxalate, glycerol as carbon source; ammonium oxalate as nitrogen source and temperature at 35℃. The phosphate solubil/zing activity further increased in the presence of the Fe^3＋ , Ca^2 ＋ , Mn^2 ＋, Zn^2 ＋in the medium,but decreased in the presence of Cu^2 ＋, Ni^2 ＋. Bmp5 was identified as B. cereus.