不同来源Burkholderia菌株对高岭石浸矿效果的影响

Effects of Burkholderia Strains from Different Sources on Kaolinite Leaching

通过摇瓶培养实验,研究两株不同来源Burkholderia菌种(BKZ01、BKZ08)对高岭石中Si、Al等主要元素的溶出动力学差异,并结合菌种的生长代谢特性,探明菌种选择性浸出矿物中主要元素的可能生物化学机制。结果表明:BKZ01具有较强代谢产苹果酸与酒石酸的能力,BKZ08不产酒石酸,但代谢产柠檬酸、草酸、胞外多糖与蛋白质的能力相对较强;BKZ01对高岭石中Si的浸出选择性要明显好于BKZ08,其浸出液中SiO_(2)的含量是BKZ08的1.55倍,而BKZ08对Al的浸出选择性要明显强于BKZ01,其浸出液中Al_(2)O_(3)的浓度是BKZ01的2.18倍。分析认为,Burkholderia代谢产物的组分与分泌量差异是影响其选择性浸出高岭石矿物中Al、Si、K、Fe等元素效率的关键因素,其中苹果酸、酒石酸与柠檬酸、草酸可分别促进细菌优先释放Si与Al;而蛋白质与多糖对细菌选择性浸出K、Fe有利。

Through shaking flask culture experiment,the dissolution kinetics of Si,Al and other main elements in kaolinite by two Burkholderia strains from different sources(BKZ01 and BKZ08)were studied.Combined with the growth and metabolism characteristics of the strains,the possible biochemical mechanism of selective leaching of main elements in minerals by the strains was explored.The results showed that BKZ01 had a stronger ability to metabolize malic acid and tartaric acid,BKZ08 did not produce tartaric acid,but had a relatively stronger ability to metabolize citric acid,oxalic acid,extracellular polysaccharide and protein.The leaching selectivity of BKZ01 to Si in kaolinite is significantly better than that of BKZ08.The content of SiO_(2) in the leaching solution is 1.55 times that of BKZ08,while the leaching selectivity of BKZ08 to Al is significantly stronger than that of BKZ01.The concentration of Al_(2)O_(3) in the leaching solution is 2.18 times that of BKZ01.The analysis shows that the composition and secretion of Burkholderia metabolites are the key factors affecting the efficiency of selective leaching of Al,Si,K,Fe from kaolinite minerals.Malic acid(tartaric acid)and citric acid(oxalic acid)can promote the preferential release of Si and Al,respectively.Protein and polysaccharide are beneficial to the selective leaching of K and Fe by bacteria.