Citrus pectin enzyme hydrolysate (PEH) of different hydrolysis time intervals (6 hours, PEH-6; 12 hours, PEH-12; 24 hours, PEH-24; or 48 hours, PEH-48) or concentrations (1%, 2%, and 4%) was tested for its growth stimulation effect on two probiotics, Bifidobacterium bifidum and Lactobacillus acidophilus. Higher monosaccharide concentrations and smaller molecular weights of PEHs were obtained by prolonging the hydrolysis time. In addition, higher PEH concentrations resulted in significantly higher (p < 0.05) probiotic populations, pH reduction, and increase in total titratable acidity than the glucose-free MRS negative control. Furthermore, significantly higher populations in the low pH environment and longer survival time in nonfat milk (p < 0.05) were observed when the two probiotics were incubated in media supplemented with 2% PEH-24, than in glucose and the negative control. In comparison with other prebiotics, addition of 2% PEH-24 resulted in a more significant increase in the probiotic population (p < 0.05) than in the commercial prebiotics. This study demonstrated that PEH derived from citrus pectin could be an effective prebiotic to enhance the growth, fermentation, acid tolerance, and survival in nonfat milk for the tested probiotics.

中文翻译：

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柑橘果胶水解物益生元作用的评价

不同水解时间间隔（6小时，PEH-6；12小时，PEH-12；24小时，PEH-24；或48小时，PEH-48）或浓度（1%、2%）的柑橘果胶酶水解物（PEH） , 和 4%) 测试其对两种益生菌，双歧杆菌和嗜酸乳杆菌的生长刺激作用。通过延长水解时间可以获得更高的单糖浓度和更小的PEHs分子量。此外，与不含葡萄糖的 MRS 阴性对照相比，较高的 PEH 浓度导致益生菌数量显着增加（p < 0.05）、pH 降低和总可滴定酸度增加。此外，当两种益生菌在补充有 2% PEH-24 的培养基中孵育时，在低 pH 环境中的种群数量显着增加，在脱脂牛奶中的存活时间更长（p < 0.05），比葡萄糖和阴性对照。与其他益生元相比，添加 2% PEH-24 导致益生菌数量的增加比商业益生元更显着（p < 0.05）。这项研究表明，从柑橘果胶中提取的 PEH 可能是一种有效的益生元，可增强所测试益生菌在脱脂牛奶中的生长、发酵、耐酸性和存活率。