9.C.19.  The PolyPhenol Uptake (PPU) Family 

Polyphenol-rich lentil hull are a potential source of nutrients for animals. Among the bioaccessible polyphenols, catechin glucoside, kaempferol tetraglucoside, procyanidin dimers and dihydroxybenzoic acid-O-dipentoside were most efficiently transported across the caco-2 membrane, and responsible for promoting intestinal integrity as a result of enhanced expression of tight junction proteins.  When ingested by rats, lentil hull polyphenols underwent extensive I and II phase metabolic reactions in vivo, including hydroxylation, methylation, glucuronidation and sulfation. Thus, lentil hull polyphenols are bioaccessible and bioavailable, and lentil hulls as a by-product can be a valuable ingredient for future functional foods (Guo et al. 2023). The transport proteins have not been identified.



Guo, F., L. Peng, H. Xiong, R. Tsao, H. Zhang, L. Jiang, and Y. Sun. (2023). Bioaccessibility and transport of lentil hull polyphenols in vitro, and their bioavailability and metabolism in rats. Food Res Int 167: 112634.