土壤耐锶细菌的筛选及其吸附效果

为了从土壤中筛选出具有耐锶性的细菌,利用牛肉膏蛋白胨固体培养基采用平板涂布的方法从土壤中分离出了12株菌株,通过其对Sr~(2+)的吸附效果对比分析,筛选出了其中4株对Sr~(2+)具有较好吸附效果的细菌进行了驯化,并对驯化前、后细菌生长速率(υA)及对Sr~(2+)的吸附效果进行了分析。结果显示:在含Sr~(2+)培养液中驯化后的细菌生长能力有明显提高,生长速率υA的峰值υA,max的位置由驯化前的1.0d提前到0.5d;同时驯化后的细菌对Sr~(2+)吸附效率均有所提高,筛选出的4株细菌在30℃、转速120r/min、pH=7、培养时间5.0d的条件下对Sr~(2+)的最佳吸附效率均可达到90%以上。

Screening and Adsorption Effect Analysis of Strontium Tolerant Bacteria in Soil

In order to screen bacteria with strontium tolerance from soil,using flat coating method in beef peptone culture medium to isolate 12 strains from soil.Through the comparative analysis of the Sr2+ adsorption effect,4 strains of bacteria which have good adsorption effect on Sr2+ to domestication was selected,and the bacterial growth rate(vA) before and after acclimation as well as the Sr2+ adsorption effect was analysed.The results show thatthe growth ability of acclimated bacteria in the culture medium containing Sr2+ is obviouslyimproved,the peak position(vA.max) of growth rate (vA) increases from 1.0 d to 0.5 d.At the same time,the adsorption efficiency of Sr2+ is improved after the domestication bacteria.The best adsorption efficiency of screened 4 strains of bacteria on Sr2+ can reach more than 90％ in the condition of temperature is 30 ℃,rotational speed is 120 r/min,pH is 7 andincubation time is 5 d.