Department of Food Science & Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
Mol Nutr Food Res. 2024 Jul;68(14):e2300555. doi: 10.1002/mnfr.202300555. Epub 2024 Jun 21.
There is a lack of research comparing how different protein isolates influence the microbiome, especially when carbohydrate (CHO) availability is varied. The objective is to determine changes in gut microbiota composition and function during fermentation of digested protein isolates under high and low CHO conditions.
Protein isolates from beef, egg white, milk, pea, and soy are subjected to in vitro digestion and fermentation with human fecal microbiota. Under low CHO conditions, the microbiota is primarily proteolytic with decreased concentrations of peptides and increased variance among microbial taxa and production of ammonia and branched chain fatty acids by the microbiota. Milk protein not only results in the highest production of butyrate and p-hydroxyphenylacetate but also has high concentrations of deleterious fermentation metabolites. Amino acid composition of the protein isolates is significantly correlated with abundances of many microbial taxa and metabolites, but the correlations are stronger in the low CHO medium.
This study shows that low CHO conditions increase proteolytic fermentation and result in increased differences in microbiota response to protein isolates. It also showed that amino acid composition is highly associated with microbiota composition and function especially under low CHO conditions.
缺乏比较不同蛋白质分离物如何影响微生物组的研究，特别是当碳水化合物（CHO）的可用性发生变化时。目的是确定在高和低 CHO 条件下消化的蛋白质分离物在发酵过程中肠道微生物群落组成和功能的变化。
从牛肉、蛋清、牛奶、豌豆和大豆中提取蛋白质分离物，并用人体粪便微生物群进行体外消化和发酵。在低 CHO 条件下，微生物群主要是蛋白水解的，肽的浓度降低，微生物类群之间的差异增加，微生物产生的氨和支链脂肪酸增加。牛奶蛋白不仅导致丁酸和对羟基苯乙酸的产量最高，而且还具有高浓度的有害发酵代谢物。蛋白质分离物的氨基酸组成与许多微生物类群和代谢物的丰度显著相关，但在低 CHO 培养基中相关性更强。
本研究表明，低 CHO 条件会增加蛋白水解发酵，导致微生物对蛋白质分离物的反应差异增加。它还表明，氨基酸组成与微生物群落组成和功能高度相关，特别是在低 CHO 条件下。
