Unveiling the microbiota-mediated impact of different dietary proteins on post-digestive processes: A simulated in...

Protein digestion and microbial metabolism play crucial roles in overall health. However, the mechanisms that differentiate the digestion and metabolism of dietary proteins from different sources in the organism remain poorly understood. This study investigated the digestive properties and microbial fermentation of various animal proteins (chicken, pork, beef, and casein) and plant proteins (soy bean, mung bean, kidney bean, rice, and wheat) in an in vitro simulation. The results indicated that animal-derived proteins had higher essential amino acid content (33.97-37.12 g/100 g) and digestibility levels (49.15-60.94 %), and provided more small molecule peptides upon digestion. Nevertheless, soy bean and wheat proteins also exhibited higher digestibility (54.70 % and 60.94 %), probably due to the extraction process. The fermentation results showed that distinct metabolic profiles that emerged for different protein sources. Plant-derived proteins (especially kidney bean, rice and wheat) promoted the proliferation of beneficial bacteria and microbial diversification and stimulated short-chain fatty acids (SCFA) production. Conversely, meat proteins (pork, chicken, beef) had significantly lower microbial diversity and SCFA than these plant proteins. These findings provide valuable insights into the effects of dietary protein sources on digestion and gut microbiome, and offer scientific guidance for optimizing dietary choices to improve health.