Yujian Wang, Xiaojuan Yang, Wei Tu, Hongyu Li
College of Life Science, Lanzhou University, Lanzhou, 730000, China.
J Microbiol Methods. 2007 Feb;68(2):212-7. doi: 10.1016/j.mimet.2006.07.013. Epub 2006 Sep 18.
By four different methods, Acidithiobacillus ferrooxidans cells were immobilized by the complex of PVA and sodium alginate. The beads formed by these different methods were evaluated in terms of relative mechanical strength, biological activity, dilatability, and so on. The results indicate that the technique utilizing the complex of PVA and sodium alginate crosslinked with Ca(NO(3))(2) is more appropriate for the immobilization of A. ferrooxidans than any others. So the PVA-calcium nitrate beads were used in batch and continuous culture. A maximum ferrous iron oxidation rate of 4.6 g/l/h was achieved in batch culture. Long-time performance of packed-bed bioreactor was evaluated systematically over 40 days, depending on the conversion ratio of ferrous iron and the residence time. At a residence time of 2.5 h, 96% of the initial ferrous iron was oxidized. This study shows this new immobilization technique will be a feasible and economical method for A. ferrooxidans.
采用四种不同方法，通过聚乙烯醇（PVA）与海藻酸钠的复合物固定嗜酸氧化亚铁硫杆菌细胞。对通过这些不同方法形成的珠子在相对机械强度、生物活性、膨胀性等方面进行了评估。结果表明，利用与Ca(NO₃)₂交联的PVA和海藻酸钠复合物的技术比其他任何技术更适合嗜酸氧化亚铁硫杆菌的固定化。因此，PVA - 硝酸钙珠子被用于分批培养和连续培养。在分批培养中实现了最大亚铁氧化速率为4.6 g/l/h。根据亚铁的转化率和停留时间，对填充床生物反应器的长期性能进行了40天的系统评估。在停留时间为2.5小时时，96%的初始亚铁被氧化。本研究表明这种新的固定化技术将是一种用于嗜酸氧化亚铁硫杆菌的可行且经济的方法。
