A method for synergistic and selective regulation of whole-cell cocatalytic synthesis of various sugar acids by metal ions

Abstract

The invention discloses a method for co-catalyzing and synthesizing multiple sugar acids by metal ions to selectively regulate whole cells, and relates to the technical field of biocatalyzing sugar synthesis of sugar acids. Main features: In the mixed sugar solution containing glucose and xylose or lignocellulose hydrolyzate, 1g / L~10g / L Gluconobacter oxidans is used as a biocatalyst to co-catalyze the synthesis of sugar from glucose and xylose under the condition of oxygen supply acid. Adding a certain concentration of metal salts containing zinc ions and ferric ions selectively inhibits the catabolism of gluconic acid by cells, but has little effect on the catalytic dehydrogenation of xylose and glucose, thereby achieving co-catalysis and efficient synthesis of glucose by cells acid (salt) and xylonic acid (salt) products, and effectively shorten the reaction time. Adopt this method, the utilization rate of glucose and xylose reaches 100%, the yield of gluconic acid exceeds 70%, the yield of xylonic acid exceeds 92%, the total concentration of product gluconic acid (salt) and xylonic acid (salt) Can exceed 30% (mass concentration).

Description

1. Technical field [0001] The invention relates to the technical field of biologically catalyzing the synthesis of sugar acids from sugars, in particular to a method for co-catalyzing and synthesizing various sugar acids in whole cells through selective regulation of metal ions. 2. Background technology [0002] Gluconic acid and xylonic acid, as polyhydroxy organic acids, can be used as food, feed additives, cement superplasticizers, dispersants, slow-release agents, concrete adhesives, plasticizers, glass cleaners, metallurgical removers, etc. Rust agent, metal ion chelating agent, textile bleaching aid, pesticide suspending agent, tanning agent and water stabilizer, etc., are widely used in food, medicine, feed breeding, chemical industry and environmental protection and other industries. The preparation and production methods of sugar acid mainly include chemical methods and biological methods. The chemical methods generally require the use of inorganic catalysts, harsh ...

AI Technical Summary

Problems solved by technology

However, in a reaction system where multiple sugar components coexist, Gluconobacter oxidans preferentially catalyzes the rapid production of gluconic acid from glucose, and the biooxidation of other sugars including xylose will be inhibited to varying degrees by glucose, resulting in a delayed effect. At the same time, the gluconic acid produced will be rapidly further catabolized by the cells and consumed in large quantities, eventually resulting in a serious loss of gluconic acid product yield (Zhou Xin, et al, Bioresources, 2015; Zhou Xin, et al, Biochemical Engineering Journal, 2015) Therefore, it is difficult to directly catalyze the lignocellulose hydrolyzate with whole cells of Gluconobacter oxydans to co-catalyze the synchronous and efficient synthesis of sugar and acid from various sugar components.

Images