Xia Jun, Xu Jiaxing, Hu Lei, Liu Xiaoyan
a Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environmental Protection, College of Chemistry and Chemical Engineering , Huaiyin Normal University , Huai'an , China.
Prep Biochem Biotechnol. 2016 Nov 16;46(8):798-802. doi: 10.1080/10826068.2015.1135464.
Poly(L-malic acid) (PMA) is a natural polyester with many attractive properties for biomedical application. However, the cost of PMA production is high when glucose is used as a carbon source. To solve this problem, cane molasses as a low-cost feedstock was applied for the production of PMA. Six pretreatment methods were applied to cane molasses before fermentation. Pretreatment with combined tricalcium phosphate, potassium ferrocyanide, and sulfuric acid (TPFSA) removed significant amounts of metal ions from cane molasses. The PMA concentration increased from 5.4 g/L (untreated molasses) to 36.9 g/L (TPFSA-pretreated molasses) after fermentation in shake flasks. A fed-batch fermentation strategy was then developed. In this method, TPFSA-pretreated cane molasses solution was continuously fed into the fermentor to maintain the total sugar concentration at 20 g/L. This technique generated approximately 95.4 g/L PMA with a productivity of 0.57 g/L/hr. The present study indicated that fed-batch fermentation using pretreated cane molasses is a feasible technique for producing high amounts of PMA.
聚（L-苹果酸）（PMA）是一种具有许多对生物医学应用有吸引力特性的天然聚酯。然而，当使用葡萄糖作为碳源时，PMA的生产成本很高。为了解决这个问题，甘蔗废蜜作为一种低成本原料被用于生产PMA。在发酵前对甘蔗废蜜应用了六种预处理方法。用磷酸三钙、亚铁氰化钾和硫酸联合预处理（TPFSA）从甘蔗废蜜中去除了大量金属离子。在摇瓶中发酵后，PMA浓度从5.4 g/L（未处理的废蜜）增加到36.9 g/L（TPFSA预处理的废蜜）。然后开发了一种分批补料发酵策略。在这种方法中，将TPFSA预处理的甘蔗废蜜溶液连续进料到发酵罐中，以将总糖浓度维持在20 g/L。该技术产生了约95.4 g/L的PMA，生产率为0.57 g/L/小时。本研究表明，使用预处理甘蔗废蜜的分批补料发酵是生产大量PMA的可行技术。
