R & D Center, Seoul Dairy Cooperative, Ansan, Gyeonggi, 15407, South Korea.
Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, South Korea.
Appl Microbiol Biotechnol. 2016 Dec;100(23):10095-10106. doi: 10.1007/s00253-016-7863-3. Epub 2016 Oct 28.
In a previous study, the synbiotic combination of selected Lactobacillus gasseri strains and Cudrania tricuspidata leaf extract (CT) was shown to significantly improve the functionality of fermented milk, and the greatest synbiotic effect was exhibited with L. gasseri 505. The aim of the present study was to investigate the growth kinetics and fermentation metabolism of this specific synbiotic combination. Fermentation was carried out in synthetic media and milk with or without CT supplementation using L. gasseri 505. Whole genome sequencing and comparative genomics analyses were conducted to verify the novelty of strain. Titratable acidity, pH, microbial population, and organic acid production were measured during the fermentation period. The addition of CT accelerated the acidification rate, supporting the growth of L. gasseri 505, and the production of fermentation metabolites such as lactic acid and pyruvic acid also significantly increased during fermentation of both of CT-supplemented synthetic media and milk. In particular, the formic acid and propionic acid in CT were significantly utilized during fermentation of milk by L. gasseri 505. Moreover, the antioxidant capacity of CT-supplemented fermented milk increased due to the release of bioactive compounds until the exponential growth phase, after which the antioxidant activity declined due to degradation and loss of potency. Therefore, this study established that L. gasseri 505 efficiently utilized the CT-related nutrients during fermentation producing resulting metabolites with health-promoting effects, although it is necessary to control the fermentation time to obtain dairy products with optimum functionality.
在之前的一项研究中，已证明特定的植物乳杆菌（Lactobacillus gasseri）菌株与三裂叶野木瓜（Cudrania tricuspidata）叶提取物（CT）的共生组合可显著改善发酵乳的功能性，其中植物乳杆菌（Lactobacillus gasseri）505 展现出最大的共生效果。本研究旨在研究该特定共生组合的生长动力学和发酵代谢。在含有或不含有 CT 补充剂的合成培养基和牛奶中使用植物乳杆菌（Lactobacillus gasseri）505 进行发酵。通过全基因组测序和比较基因组学分析来验证该菌株的新颖性。在发酵过程中测量可滴定酸度、pH 值、微生物种群和有机酸生成。CT 的添加加速了酸化速率，支持植物乳杆菌（Lactobacillus gasseri）505 的生长，并且在 CT 补充的合成培养基和牛奶的发酵过程中，发酵代谢产物（如乳酸和丙酮酸）的产生也显著增加。特别是在植物乳杆菌（Lactobacillus gasseri）505 发酵牛奶的过程中，CT 中的甲酸和丙酸被显著利用。此外，由于生物活性化合物的释放，CT 补充发酵乳的抗氧化能力增加，直到指数生长期，此后由于降解和效力丧失，抗氧化活性下降。因此，本研究证实植物乳杆菌（Lactobacillus gasseri）505 在发酵过程中有效地利用 CT 相关营养物质产生具有促进健康作用的代谢产物，尽管有必要控制发酵时间以获得具有最佳功能的乳制品。
