R & D results

　　Project aspect:

　　①Riboflavin production system engineering design optimization

　　Core technology: Screening and verifying the ingredients of key materials (molasses, cottonseed meal, etc.) through small tests to improve yield and material conversion rate; systematic optimization and stability verification of riboflavin production process, including fermentation process Optimization, transformation of production equipment to increase utilization, etc., to solve pollution problems from the source.

　　Innovation points: optimizing the ratio and substitution of key fermentation materials to increase the yield of riboflavin fermentation; regulating the process control of riboflavin fermentation, shortening the production cycle, reducing energy consumption and costs; optimizing the process system through pilot trials, and reducing waste materials Recycling and utilization.

　　②Study on fermentation technology of adenosine production by fermentation of clear liquid

　　Core technology: adenosine fermentation condition optimization and process control, involving orthogonal test method, response surface method to optimize adenosine fermentation medium, 30 L fermenter fermentation process control and condition optimization, 30 L fermenter adenosine fed-batch fermentation The research on the efficient separation and extraction process of adenosine ensures product quality and improves product yield.

　　Innovation points: simplification of fermentation formula, higher quality of fermentation materials, improved extraction yield, lower energy consumption and production costs; independent research and development of adenosine clear night fermentation technology and post-extraction technology are at the leading domestic level. After mass production, Greatly increase the production capacity of adenosine and have strong domestic and foreign market competitiveness.

　　③The effect of high-performance stirring blade on dissolved oxygen and fluid mass transfer in tryptophan fermentation

　　Core technology: the stirrer type selection and fermentation experiment was conducted at the level of 50L fermentation tank to determine the optimal stirrer type, rotating speed and optimum pH conditions.The optimized l-tryptophan fermentation process established in the pilot test was successfully enlarged in a 10m3 tank.The industrial scale 330m3 tank application of L-tryptophan fermentation Optimization process.

　　Innovation points: The suitable agitator can effectively reduce energy consumption and increase the concentration of dissolved oxygen in the fermentation broth;Suitable for the industrial production of L-tryptophan the optimal stirring paddle model, speed and pH conditions, effectively improve the economic benefits.

　　④Industrial project on the production of α-ketoglutaric acid by cell (enzyme) catalysis

　　Core technology: Immobilized enzyme technology is used to improve the activity of glutamate oxidase and the conversion rate of fermentation to improve its enzyme activity, which has significance for the large-scale industrial production of a-ketoglutaric acid and the further improvement of production level of a-ketoglutaric acid in China.

　　Innovation points: The metabolic engineering transformation of α-ketoglutaric acid production strain involves the construction of genome integrated expression system, the blocking of α-Ketoglutaric acid degradation pathway, the enhancement of α-Ketoglutaric acid synthesis pathway and the enhancement of intracellular oxygen transfer rate.α-ketoglutaric acid fermentation process control and process optimization, involving the flask condition optimization, 30 L fermentation tank fermentation process control and condition optimization;The extraction process of α-ketoglutaric acid was studied, including the influence of operating conditions on membrane flux during microfiltration, the screening of cation exchange resin, and the influence of ultrasonic oscillation on the extraction of α-Ketoglutaric acid.

　　⑤Study on enzyme immobilization during ketoglutaric acid conversion

　　Core techniques: collection of bacterial cells after α-ketoglutaric acid fermentation, preservation of protease activity and pretreatment of cells;Glutamate oxidase was immobilized by different enzyme immobilization techniques, and appropriate crosslinking agent and carrier were selected to delay the inactivation time and improve the conversion rate.

　　Innovation points: The high-efficiency production strain and its fermentation process were used to scale up production in a 50 m3 fermentation tank. The acid production level of -ketoglutaric acid was ≥100 g/L, the conversion rate was ≥90%, and the fermentation cycle was ≤24 h.

　　⑥Industrial research project on production of L-alanine by cell (enzyme) catalysis

　　Core technology: culture of bacteria -- adaptive adjustment of the fermentation formula, through the implementation of this series of measures, to the maximum extent to meet the growth conditions and catalytic activity of bacteria;Extraction process -- Aiming at the condition that the solubility and temperature of alanine are not linear, the extraction process that conforms to the equipment performance is studied from the pH and temperature aspects, which greatly improves the operability of the process.In order to solve the problems of low yield and poor quality of L-alanine, an efficient separation and extraction process of L-alanine based on membrane system, cell immobilization and ultrasonic crystallization was developed.

　　Innovation point: Amplification production was carried out in 300 m3 fermentation tank by using the constructed high-efficiency production strain and its fermentation process. L-alanine acid production level ≥120g/L, conversion rate ≥80%, and fermentation cycle ≤40 h.

　　⑦Study on extraction technology of L-leucine

　　New product development: We have do the small test ,middle test and the workshop industrialized production activities of these products:L-hydroxyproline, adenosine, adenosine cyclophosphate, N-acetylglucosamine, L-2-aminobutyric acid, L-4 hydroxyisoleucine, L-arginine,and some products have been into the market.

　　Up to now, the company’s technology center has applied for 8 achievements appraisal, of which 2 scientific and technological achievements have been applied for and passed the appraisal from 2017 to 2018, namely:

　　①Key technology and industrialization of hydroxylated amino acid biosynthesis: This achievement was comprehensively evaluated as the international advanced level by the expert group of China National Light Industry Council;

　　②The key technology and industrialization of metabolic regulation of purine nucleosides and their derivatives: This achievement was comprehensively assessed as the international leading level by the expert group of China National Light Industry Council.