粤北大宝山矿区土壤中抗铅菌株的筛选鉴定

Screening and identification of Pb-resistance strain from Dabaoshan mining area in Northern Guangdong Province

采集大宝山矿区重金属污染的土壤样品,采用稀释涂布平板法对土壤样品中抗铅菌株的筛选,进一步在含不同铅浓度的培养液中进行驯化;通过对该菌株的形态观察、一系列生理生化试验、以及16S r DNA序列的比对研究进行鉴定;利用原子荧光光度计测定其对发酵液中铅的吸附能力。结果表明,分离获得的抗铅菌株在铅浓度为500 mg·L-1的培养液中长势良好,鉴定为类短短芽孢杆菌(Brevibacillus parabrevis),该菌株在含铅浓度为300mg·L-1的液体培养情况下,培养20 h左右,对发酵液中铅的去除效率高,高达30.27%。

Using the method of dilution butteron on plate, a Pb-resistance strain was screened from the heavy metal polluted soil in Dabaoshan mining area, north of Guangdong Province. The strain was further acclimatized by culturing in liquid medium containing different lead concentrations. The strain was identified by cell morphology, physiological and biochemical characteristics, and 16 S r DNA sequence alignment. Further its Pb adsorption capacity in fermentation broth was determined by atom fluorescence spectrometry. The results showed a Pb-resistance strain was obtained and it grew well in the condition of 500 mg/L Pb. This strain was identified as Brevibacillus parabrevis. Cultured in liquid medium containing 300 mg/L Pb, the strain had the highest Pb removal efficiency（30.27%） after culturing for 20 hours.