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bioRxiv · 10.1101/2023.11.30.569454

Simulated digestion, uptake and colonic fermentation of Gorse (Ulex europeaus) suggests safe use as a source of protein concentrates and potential bioactives.

Abstract

BackgroundInvasive plants such as Gorse (Ulex europeaus) may serve as a potentially sustainable source of edible proteins and bioactives through the production of leaf protein concentrates (GLPC). The digestion, uptake and safety of phytochemicals from GLPC and the protein depleted but bioactive rich fraction (PDF) from Gorse was studied using an in vitro simulated digestion model. ResultsBoth the Gorse fractions and their digesta maintained the viability of cultured (Caco-2) intestinal cells above the 80% threshold, suggesting a lack of overt toxicity. In the digestion model, most of the plant metabolites in the digesta were largely confined to the apical fraction of the Caco-2 monolayer (representing the lumen) and were subsequently expected to be delivered to the colon. Food matrix had a significant but marginal effect on the permeability of metabolites across the Caco-2 monolayer. Lastly, in vitro intestinal microbial action appeared to produce beneficial compounds such as enterolactones, and equol. ConclusionThe Gorse fractions lack general overt toxicity to Caco-2 cells. GLPC and PDF provide metabolic substrates for the colonic microbes to produce secondary compounds that are associated with positive health outcomes.

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Iyer, A., Duncan, G. J., Hayward, N. J., Bestwick, C. S., Duncan, S. H., Russell, W. R.. 2023-11-30. Simulated digestion, uptake and colonic fermentation of Gorse (Ulex europeaus) suggests safe use as a source of protein concentrates and potential bioactives.. https://doi.org/10.1101/2023.11.30.569454

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