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Pyruvate an important intermediate in the process of glucose metabolism, have a wide range of applications in the chemical, pharmaceutical and agricultural chemicals and other industrial and scientific research. In recent years, the world's growing demand for its commercial. , Pyruvate production methods have begun to shift from the initial chemical synthesis of microbial fermentation synthesis. This article Torulopsis (Torulopses glabrata) obtained by liquid fermentation pyruvate as the original strain. The main contents are as follows: experiments, pyruvate fast determination method. Pyruvate detection using conventional chemical method in the past, a byproduct in the fermentation broth of α-ketoglutarate interested measurement result of a greater interference, several determination methods of comparison, traditional iron ion complex optimization, dual-wavelength spectrophotometric determination of the content of pyruvate in the fermentation broth can eliminate matrix background, color and α-ketoglutarate interference. Measurement wavelength of 510 nm, parameters than the wavelength of 540 nm. Recovery rate of 99. 02%, RSD 0.48%, the method is simple, low cost, accurate and reliable. Experiments to optimize the pyruvate fermentation parameters. Optimization of the seed culture conditions to determine the best seed age 20 h, the optimal seed medium carbon source glucose the seed medium formula: glucose 40 g / L, peptone 4 g / L, magnesium sulfate 0.3 g / L, potassium dihydrogen phosphate, 1 g / l. Optimization of fermentation conditions to determine optimum liquid loading 42mL/250 mL, and the optimal dosage of calcium carbonate 32 g / L, the optimum temperature control program for 0-8 h, 33 ℃ culture, 9 - 36 hours, 30 ° C culture ,37-56 h, 28 ℃ culture. The Box-Behenken center in response to the fermentation medium, the response surface analysis to determine glucose, ammonium sulfate and peptone as the main factors in the fermentation medium, the best combination of ammonium sulfate, 6.5 g / L, glucose 108.6 g peptone / L, 1.92 g / L. The yield was 63 g / L, 17.53 percent higher than before optimization. Experimental use dual enzymatic hydrolysis of starch, starch sugar fermentation production of pyruvate. Amylase hydrolysis conditions: pH 6.3-6.5, temperature 93 ° C, hydrolysis time 20 min, the enzyme dosage of 15 U / g, 20% starch concentration on the the amylase hydrolysis conditions optimized by univariate analysis. Through the center of the Box-Behenken response analysis to determine glucoamylase hydrolysis conditions: pH 4.5, temperature 62.8 ° C, hydrolysis time of 27 hours, the amount of enzyme 170 U / g final DE value of 91.59%.
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