Abstract

Probiotic bacteria continue to receive increasing attention in the food and feed industries. However, the production of Bifidobacterium and Lactobacillus at an industrial scale is challenging because of specific nutrient requirements and conditions, which are complicated and costly. We developed low-cost culture media by modifying the carbon and nitrogen sources for Bifidobacterium animalis subsp. lactis KMP-H9-01 and Lactobacillus reuteri KMP-P4-S03 from available food grade components. Sucrose (15 g/l) was selected as a suitable carbon source for both strains because it was the most economic and facilitated bacterial growth that was equal to that of glucose. The Bifidobacterium strain required beef extract as a nitrogen source to multiply. The fermentation of both strains using the modified media formula in 5-L and 50-L bioreactors showed that the highest cell counts of L. reuteri and B. animalis subsp. lactis were 9 and 9.8 log CFU/ml after 12–15 h, respectively. The concentration (g/l) ratio between lactate and acetate obtained from B. animalis subsp. lactis was 7:7.4 at 12 h and 11.4:10.6 at 40 h; the ratio was similar at both time points (6.9: 1.1) for L. reuteri. Thus, this economically modified food-grade medium for the large-scale fermentation of two probiotic bacteria was efficient.

 抽象的

益生菌在食品和饲料行业中继续受到越来越多的关注。然而，由于特定的营养需求和条件，双歧杆菌和乳酸菌的工业规模生产具有挑战性，且复杂且成本高昂。我们通过改变动物双歧杆菌亚种的碳源和氮源开发了低成本培养基。乳酸菌KMP-H9-01 和罗伊氏乳杆菌KMP-P4-S03 来自可用的食品级成分。选择蔗糖（15克/升）作为两种菌株的合适碳源，因为它与葡萄糖一样最经济且有利于细菌生长。双歧杆菌菌株需要牛肉提取物作为氮源才能繁殖。使用改良培养基配方在 5 L 和 50 L 生物反应器中对两种菌株进行发酵表明，路伊氏乳杆菌和动物芽孢杆菌亚种的细胞计数最高。 12-15 小时后，乳酸菌分别为 9 和 9.8 log CFU/ml。从动物芽孢杆菌亚种获得的乳酸和乙酸之间的浓度（克/升）比。 12小时时乳酸为7:7.4，40小时时乳酸为11.4:10.6；罗伊氏乳杆菌在两个时间点的比率相似 (6.9: 1.1)。因此，这种经济改良的食品级培养基对于两种益生菌的大规模发酵是有效的。