【摘要】 D-塔格糖（D-tagatose）是一种新型甜味剂,具有降低血糖、改善肠道菌群等功能,被广泛用于食品及药品等领域。植物乳杆菌WU14（Lactobacillus plantarum WU14）可通过L-阿拉伯糖异构酶转化D-塔格糖,为提高其转化能力,以植物乳杆菌WU14的生物量及L-阿拉伯糖异构酶酶活为指标,通过单因素实验与响应面实验对高产D-塔格糖植物乳杆菌WU14发酵培养基及培养条件进行优化。结果表明,发酵培养基组成为（g/L）:葡萄糖4.35 g、L-阿拉伯糖2.71 g、酵母浸粉17.6g、大豆蛋白胨17.6 g、无水乙酸钠10 g、MgSO₄·7H₂O 0.4 g、MnSO₄·2H₂O 0.05 g、K₂HPO₄ 0.4g;发酵条件为:发酵初始pH值6.24、发酵温度28.6℃、接种量2%、发酵20 h,在此条件下,植物乳杆菌WU14的菌体量比优化前提高了近48%,L-阿拉伯糖异构酶酶活达42.23 U/mL,D-塔格糖的转化率达到69.6%。培养基的优化显著提高植物乳杆菌WU14的菌体量及L-阿拉伯糖异构酶活力,为D-塔格糖进一步工业化发酵生产提供理论基础。更多还原

【Abstract】 D-tagatose is a new sweetener that has the functions of lowering blood sugar and improving intestinal flora, and is widely used in food and medicine. Lactobacillus plantarum WU14 has the ability to transform D-tagatose by L-arabinose isomerase. In order to improve the ability of tranformation, the biomass and the activity of L-arabinose isomerase of L. plantarum WU14 were used as the indicators, the single factor and response surface analysis were employed to optimize the fermentation medium and conditions of L. plantarum WU14 with high D-tagatose yield. The results showed that the optimal composition of the fermentation medium was（g/L）: glucose 4.35 g, L-arabinose 2.71 g, yeast extract powder 17.6 g, soy peptone 17.6 g, anhydrous sodium acetate 10 g, MgSO₄·7 H₂O 0.4 g, MnSO₄·2 H₂O 0.05 g, K₂HPO₄ 0.4 g; fermentation conditions: initial pH6.24, fermentation temperature 28.6 ℃, inoculum 2%, fermentation 20 h. With these optimizations, the biomass of L. plantarum WU14 increased by nearly 48%, the L-arabinose isomerase activity reached 42.23 U/mL and the conversion rate of D-tagatose reached 69.6%. The optimization of the medium significantly increased the biomass and L-arabinose isomerase activity of L. plantarum WU14, which provided a theoretical basis for further industrial fermentation production of D-tagatose.更多还原