Department of Biotechnology, Mepco Schlenk Engineering College, Sivakasi, 626 005, Tamil Nadu, India.
Appl Biochem Biotechnol. 2013 Nov;171(6):1328-38. doi: 10.1007/s12010-013-0425-6. Epub 2013 Aug 16.
Bacillus badius isolated from soil has been identified as potential producer of penicillin G acylase (PGA). In the present study, batch experiments performed at optimized inoculum size, temperature, pH, and agitation yielded a maximum PGA of 9.5 U/ml in shake flask. The experiments conducted in bioreactor with different oxygen flow rates revealed that 0.66 vvm oxygen flow rate could be sufficient for the maximum PGA activity of 12.7 U/ml. From a detailed investigation on the strategies of the addition of phenyl acetic acid (PAA) for increasing the production of PGA, it was found that the controlled addition of 10 ml of 0.1 % (w/v) PAA once in every 2 h from 6th hour of growth showed the maximum PGA activity of 32 U/ml. Thus, our studies for the first time showed that at concentration above 0.1 % (w/v) PAA, the PGA production decreased. This selective condition paves the way for less costly bioprocess for the production of PGA.
从土壤中分离出的短芽孢杆菌已被鉴定为青霉素 G 酰化酶 (PGA) 的潜在生产菌。在本研究中，在优化的接种量、温度、pH 值和搅拌条件下进行分批实验，在摇瓶中得到了 9.5 U/ml 的最大 PGA。在不同氧流速的生物反应器中进行的实验表明，0.66 vvm 的氧流速足以获得 12.7 U/ml 的最大 PGA 活性。通过对添加苯乙酸 (PAA) 以提高 PGA 产量的策略进行详细研究，发现从生长的第 6 小时开始，每隔 2 小时添加一次 10ml0.1%（w/v）的 PAA，可使 PGA 活性达到 32 U/ml。因此，我们的研究首次表明，在 PAA 浓度高于 0.1%（w/v）时，PGA 的产量会下降。这种选择性条件为生产 PGA 的成本更低的生物过程铺平了道路。
