文献类型：期刊文献

英文题名：Effects of dissolved oxygen on the biooxidation process of refractory gold ores

作者：Sun, Li-Xin[1];Zhang, Xu[1];Tan, Wen-Song[1];Zhu, Ming-Long[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2012

卷号：114

期号：5

起止页码：531

外文期刊名：JOURNAL OF BIOSCIENCE AND BIOENGINEERING

收录：;EI(收录号：20123915465414);WOS:【SCI-EXPANDED(收录号:WOS:000312630000011)】；

基金：This study was financially supported by Open Project Funding of State Key Laboratory of Bioreactor Engineering of China and the National High Technology Research and Development Program of China (Nos. 2007AA060904 and 2012AA061503).

语种：英文

外文关键词：Refractory sulfide gold ores; Biooxidation process; Dissolved oxygen; Acidithiobacillus ferrooxidans; Stirred tank bioreactors

摘要：While multiple theories exist regarding the effect of dissolved oxygen (DO) on the biooxidation of minerals, few studies have been performed the cellular or molecular scale (e.g., genetics) and the mechanism remains unclear. In this paper, the effects of DO concentration on the biooxidation process of refractory sulfide gold ores by Acidithiobacillus ferrooxidans were investigated in the experimental stirred tank bioreactors (STRs). The results indicated that higher biooxidation and cell growth rates were correlated with higher DO concentration. The biooxidation process was restricted at 1.2 ppm DO due to oxygen limitation. Furthermore, the effects of DO on cellular and molecular scale were studied for the first time. The results demonstrated that the oxygen uptake rate (OUR), the Fe2+ oxidation activity and the rus gene expression of A. ferrooxidans all increased with the DO concentration, which might be responsible for the increase of the biooxidation rates with the DO concentration. This study provides insight into the potential impact of molecular-level mechanisms of DO in the biooxidation process of minerals. (C) 2012, The Society for Biotechnology, Japan. All rights reserved.