Impact of in vitro digestion on the cytotoxicity and microbial viability of cholinesterase-inhibitor-rich vegan soups in human intestinal cell models.

Vegan lunch soups formulated with mushroom, asparagus, leek, and sea buckthorn were previously developed by our team to provide a consistent daily intake of dietary cholinesterase inhibitors. Considering the proposed continuous consumption of these functional soups, it is essential to examine any cytotoxic responses that may occur in the gastro-intestinal tract. This work starts this topic by investigating the effect of in vitro digested soups towards selected human intestinal cells and intestinal bacteria. Reduced viability of Lactobacillus and Bifidobacterium strains after 24 h of incubation of each soup with bacteria in the "large intestine" was observed, but it was not statistically (P < 0.05) confirmed. Sea buckthorn soup demonstrated the highest cell counts and these observations were confirmed by SEM analysis. All soups (at 1 % and 2.5 % in the medium) showed decreased metabolism of healthy colon epithelial CCD 841 cells (MTT and NR tests). Metabolism of colorectal cancer HT-29 cells was reduced by leek soup (at 0.01 % - 2.5 %) and all other soups at 2.5 % (MTT test), but no effect was observed in MTT test. Asparagus soup decreased the percent number of CCD 841 cells at early apoptosis large stage and all soups increased the percent of CCD 841 cells at the necrosis stage. All soups decreased the percent of HT-29 cells in S phase. Also, mushroom and leek soups increased the percent of HT-29 cells in G2 phase.