Simulated digestion of olive pomace water-soluble ingredient: Relationship between the compounds bioaccessibility and their potential health benefits

Olive pomace is a semisolid by-product with a great potential as a source of bioactive compounds. Using its soluble fraction, a liquid-enriched powder (LOPP) was obtained, exhibiting a rich composition in sugars, polyphenols and minerals, with potential antioxidant, antihypertensive and antidiabetic health benefits. To validate LOPP potential as a functional ingredient the effect of the gastrointestinal tract on its bioactive composition and bioactivities was examined. Polyphenols and minerals were the most affected compounds, however, a significant bioaccessibility of potassium and hydroxytyrosol was verified ( 57 %). As a consequence, the LOPP bioactivities were only moderately affected (losses around 50%). For example, 57.82 ± 1.27 % of the recovered antioxidant activity by ORAC was serum - available. From an initial -glucosidase inhibition activity of 87.11 ± 1.04 %, at least 50% of the initial potential was kept (43.82 ± 1.14 %). Regarding initial ACE inhibitory activity (91.98 ± 3.24 %), after gastrointestinal tract losses, significant antihypertensive activity was retained in the serum-available fraction (43.4 ± 3.65 %). The colon-available fraction also exhibited an abundant composition in phenolics and minerals. LOPP showed to be a potential functional ingredient not only with potential benefits in preventing cardiovascular diseases but also in gut health.