Pea protein isolate and sour cherry polyphenols interaction improved the stability of polyphenols and the efficacy in alleviating colitis

Abstract

To enhance the bioavailability of sour cherry polyphenol extract (SCE), pea protein isolate (PPI) with low allergenicity was selected to form the complex with SCE. The storage and digestion characteristics of the complex, along with its effects on relieving colitis were evaluated. The results showed that after complexing with PPI, the storage stability of SCE was improved. After digestion, the PSA group (PPI-SCE complex prepared at pH 3) delivered more polyphenols to the small intestine. PSA was more effective in alleviating ulcerative colitis compared with SCE alone, which inhibited the excessive activation of the TLR4/NF-κB pathway. The shortening of the colon length was mitigated. It was manifested in a reduction in inflammatory factor levels, alleviation of colonic damage, and less tissue structure destruction. Meanwhile, PSA upregulated the gene expression of tight-junction proteins such as zonula occludens-1, occludin, and claudin-4, enhancing the integrity of the intestinal barrier and thus alleviating the symptoms of ulcerative colitis. This study provided a reference for the high-value utilization of SCE and the extensive application of PPI.