中文摘要：

以从河南铝土矿样筛选出的一株胶质芽孢杆菌HJ07为出发菌株，对其进行紫外（UV）与亚硝基胍（NTGl诱变育种及铝土矿浸矿脱硅研究．分别通过紫外线照射120S与采用质量浓度为600mg·L^-1的亚硝基胍处理，出发菌株HJ07的致死率分别达到89％与90％，正突变率分别达到16．5％与18．7％．从突变菌株中筛选所得的两株菌种UV-2与NTG-5的生长代谢活性与脱硅能力明显比出发菌株高．在铝土矿浸出体系中，UV-2与NTG-5达到生长稳定期的时间比HJ07分别缩短了48h与24h，且生长稳定期具有更大的细菌浓度．浸矿12d后，UV-2与NTG-5菌株浸出液中SiO2的质量浓度分别比HJ07提高了约25．6％与12．5％，且达到浸出终点的时间分别缩短了3d和2d．UV-2与NTG．5菌株较出发菌株HJ07具有更强的产酸与产胞外聚合物的能力．被UV-2菌株作用后的铝土矿表面的溶蚀程度更加显著，矿物表面形成了明显的菌胶团．

英文摘要：

An original strain Bacillus mucilaginosus H J07 was screened from bauxite sampled from Henan Province of China. It was induced mutagenesis by ultraviolet （UV） radiating and nitrosoguanidine （NTG） culturing, and then was used for bioleaching silicon from bauxite. After treated by 120 s UV radiating and 600 mg.L-1 NTG culturing, its kill rates are 89% and 90%, and its positive mutation rates are 16.5% and 18.7%, respectively. Two mutant strains UV-2 and NTG-5 were screened from a large number of mutant strains, and they have better bioactivity and de-silicon efficiency than H J07 strain. In comparison with H J07 strain, the time that UV-2 and NTG-5 strains reach stable growth in bauxite bioleaching systems shortens by 48 h and 24 h, respectively, and they have higher bacterial concentrations. After 12 d bioleaching, SiO2 mass concentrations in leachates of UV-2 and NTG-5 stains improve by about 25.6% and 12.5%, and the time that UV-2 and NTG-5 strains reach the leaching terminal point shortens by 3 d and 2 d, respectively. UV-2 and NTG-5 strains can produce much more organic acids and extracellular polymeric substances than H J07 strain. Moreover, mineral particle surfaces leached by UV-2 strain are eroded much more obviously and covered with a thicker layer of zooglea.