Food Amyloid Fibrils as Safe Nutrition Ingredients: In-vitro and In-vivo Assessment

Abstract If safety concerns could be conclusively disproven, food protein amyloid fibrils would constitute superior ingredients compared to native monomers from a technological, nutritional, sensorial, and physical perspective. Here, we show, by combining SDS-PAGE, ELISA, fluorescence, AFM, TEM, MALDI-MS, CD, microfluidics, and SAXS techniques on β-lactoglobulin and lysozyme amyloid fibrils subjected to in-vitro gastrointestinal digestion, that either no noticeable differences exist between amyloid aggregates and their monomer counterparts after the gastrointestinal digestion process (as in β-lactoglobulin), or that amyloid fibrils are even digested significantly better than monomers (as in lysozyme). Both amyloid protein sources are digested down to unfolded oligopeptides well-below amyloid nuclei size and deprived of the β-sheet amyloids hallmark signature. We further conclude via in-vivo studies on both C. elegans and mice animal models that the digested fibrils present no observable toxicity to the investigated animal models. These results suggest that final peptides digested from food amyloids fibrils are at least equally safe than those obtained from the digested corresponding native monomers and feature no detectable toxicity in-vivo, pointing to food amyloid fibrils as potential ingredients for human nutrition.