在这项研究中,各种益生菌菌株,包括植物乳杆菌,干酪乳杆菌,嗜酸乳杆菌,嗜热链球菌,长双歧杆菌,罗伊利氏杆菌,德氏乳杆菌亚种。保加利亚,鼠李糖乳杆菌,和双歧杆菌,用于豆浆发酵,既作为游离细胞,又作为农产工业残余物如豆渣的合生元,乳清蛋白,香蕉皮,苹果渣,甘蔗渣,橘子皮,和柠檬皮。其中,鼠李糖乳杆菌是豆浆发酵最重要的菌株,表现出10.47logcfu/mL的活力,pH值为4.41,总酸度为1.12%,和有机酸含量(乳酸和乙酸)为11.20和7.50g/L,分别。作为固定在豆渣上的合生体鼠李糖乳杆菌,表现出更令人印象深刻的结果,活力为12.98logcfu/mL,pH值为4.31,总酸度为1.27%,有机酸含量分别为13.90和9.30g/L,分别。经过12小时的发酵,游离细胞中的细胞活力值增加了10.47倍,合生元中的细胞活力值增加了11.19倍。在生存力方面,发酵豆浆的合生元补充被证明比游离细胞更有益,酸度,和有机酸含量。此外,当合生元发酵豆浆冷冻干燥以模拟体外消化系统时,合生元和冷冻干燥的细胞与游离细胞相比表现出优越的胃肠道存活率。益生菌和合生元对结肠癌和肝癌细胞系都表现出细胞毒性,半最大抑制浓度范围为41.96至61.52μL/孔。
In this study, a variety of probiotic strains, including Lactiplantibacillus plantarum, Lacticaseibacillus casei, Lactobacillus acidophilus, Streptococcus thermophilus, Bifidobacterium longum, Limosilactobacillus reuteri, Lactobacillus delbrueckii subsp. bulgaricus, Lacticaseibacillus rhamnosus, and Bifidobacterium bifidum, were utilized for soymilk fermentation both as free cells and as synbiotics on agro-industrial residuals such as okara, whey protein, banana peels, apple pomace, sugarcane bagasse, orange peels, and lemon peels. Among these, Lacticaseibacillus rhamnosus emerged as the most significant strain for soymilk fermentation, exhibiting a viability of 10.47 log cfu/mL, a pH of 4.41, total acidity of 1.12%, and organic acid contents (lactic and acetic acid) of 11.20 and 7.50 g/L, respectively. As a synbiotic Lacticaseibacillus rhamnosus immobilised on okara, showed even more impressive results, with a viability of 12.98 log cfu/mL, a pH of 4.31, total acidity of 1.27%, and organic acid contents of 13.90 and 9.30 g/L, respectively. Over a 12-h fermentation period, cell viability values increased by 10.47-fold in free cells and 11.19-fold in synbiotics. Synbiotic supplementation of fermented soymilk proved more beneficial than free cells in terms of viability, acidity, and organic acid content. Furthermore, when synbiotic fermented soymilk was freeze-dried to simulate the digestive system in vitro, synbiotics and freeze-dried cells demonstrated superior gastrointestinal tract survival compared to free cells. Both the probiotic bacteria and the synbiotics exhibited cytotoxicity against colon and liver cancer cell lines, with half-maximal inhibitory concentrations ranging from 41.96 to 61.52 μL/well.