高丙酮酸黄原胶的发酵研究

Study on the production of high-pyruvate-content xanthan by exocellular enzymes

为得到高丙酮酸黄原胶,进行了黄原胶的除细胞法发酵研究。采用单因素法和正交实验法,对发酵液pH、发酵温度以及发酵培养基成分进行了优化,并考察了游离丙酮酸和NH4Cl的加入量对丙酮酸含量的影响。结果表明:发酵培养基的组成为蔗糖50g/L、酵母膏0.08g/L、KCl15g/L、KH2PO40.06g/L、MgSO40.8g/L、CaCO36.0g/L、柠檬酸0.015g/L、游离丙酮酸2.0g/L、NH4Cl3.0g/L时,在pH7.2,温度32℃下进行发酵实验,丙酮酸含量可达到4.82%。

The synthesis of high-pyruvate-content xanthan was studied by enzymes fermentation. To improve pyruvate content,pH value,temperature and the fermentation medium for xanthangum were studied with monofactorial experiments and orthogonal design. Meanwhile,the effects of free pyruvate acid and NH4Cl on pyruvate content was studied. The optimal medium for producing xanthan was： sucrose 50g/L,yeast extract 0.08g/L,KCl 15g/L, KH2PO4 0.06g/L, MgSO4 0.8g/L, CaCO3 6.0g/L, citric acid 0.015g/L, free pyruvate acid 2.0g/L and NH4Cl 3.0g/L. Under the conditions of the initial pH 7.2 and 32℃,the pyruvate mass fraction was 4.82%.