Pea dietary fiber for adhesion and excretion of enterotoxigenic E. coli K88 to prevent intestinal colonization

Enterotoxigenic Escherichia coli (ETEC) expressing K88 (F4) fimbriae are associated with post-weaning diarrhea in piglets. Dietary components as well as feed additives can interfere with the colonization of the porcine intestine by ETEC. Digestion resistant fibers, for example, can competitively inhibit the adherence of ETEC to host intestinal tissues. Grain legumes such as peas or faba beans are alternative plant protein sources to soybeans in animal feed that can be cultivated in temperate climates. In fact, these crops are not only rich in protein, but also contain starch and fiber. The aim of this study was to test the binding capacity for ETEC O149:K91:K88ac (LT+/STb+) of pea (Pisum sativum, cv. Attika) and faba bean (Vicia faba, cv. Divine), and of different fractions of these grain legumes obtained before and after in vitro digestion. All products were milled to a particle size of less than 1 mm. In vitro digestion was performed using pepsin and pancreatin. Adhesion of ETEC K88 to the pea and bean materials was determined in a microplate-based binding assay. When comparing the raw products, pea hulls, pea inner fiber, whole pea, pea starch and pea protein scored higher in terms of adhesion of ETEC K88 than faba bean starch, whole faba bean, faba bean protein and faba bean hulls. Pea hulls proved even superior to a commercial yeast cell wall product in terms of the binding capacity for ETEC K88. After in vitro digestion, the binding capacity for ETEC K88 remained preserved in washed digestion remnants of both pea hulls and whole pea, indicating the potential of these products to offer alternative adhesion sites for ETEC K88 to host receptors in the piglet small intestine