Chongqing University, Chongqing 400044, China; Research Center for Tobacco Bioengineering and Technology of Chongqing Science and Technology Commission, Chongqing 401147, China; China Tobacco Chongqing Industrial Co. Ltd., Chongqing 400000, China.
Chongqing University, Chongqing 400044, China; Research Center for Tobacco Bioengineering and Technology of Chongqing Science and Technology Commission, Chongqing 401147, China.
Bioresour Technol. 2017 Oct;241:1138-1144. doi: 10.1016/j.biortech.2017.06.066. Epub 2017 Jun 21.
In this study, highly reactive endo- and exo-polygalacturonases (PGs) were produced from the tobacco industry wastewater using immobilized Rhizopus oryzae. Compared with free cells, immobilized cells increased enzyme activity 2.8-fold and reduced production time to 24h by shake-flask production. Moreover, the immobilized cells enabled the semi-continuous production of enzymes through repeated-batch mode for seven consecutive cycles in a scale-up bioreactor. During the first five cycles, the average endo-PG and exo-PG activities reached 307.5 and 242.6U/ml, respectively. The addition of crude enzyme for the hydrolysis of pectin-containing lignocellulosic biomass under high-gravity conditions increased glucose release 4.2-fold (115.4 vs. 29.0g/L), compared with hydrolysis using cellulase alone. This process achieves the efficient production of pectin-degrading enzymes, provides a cost-effective method for tobacco wastewater treatment, and offers the possibility to obtain fermentable sugars with high-titer from pectin-containing lignocellulosic biomass, which has important potential for the commercial production of bio-fuels.
在这项研究中，利用固定化米根霉从烟草工业废水中生产出了高反应性的内切和外切多聚半乳糖醛酸酶（PGs）。与游离细胞相比，固定化细胞通过摇瓶生产将酶活性提高了 2.8 倍，并将生产时间缩短至 24 小时。此外，固定化细胞通过在扩大规模的生物反应器中重复分批模式进行了七轮连续循环，实现了酶的半连续生产。在前五个循环中，内切 PG 和外切 PG 的平均酶活分别达到 307.5 和 242.6U/ml。与单独使用纤维素酶相比，在高浓度条件下添加粗酶进行含果胶木质纤维素生物质水解可将葡萄糖释放量提高 4.2 倍（115.4 比 29.0g/L）。该过程实现了果胶降解酶的高效生产，为烟草废水处理提供了一种具有成本效益的方法，并为从含果胶木质纤维素生物质中获得高浓度可发酵糖提供了可能，这对于生物燃料的商业生产具有重要的潜在价值。
