The beneficial properties associated with garlic consumption have been related to the presence of bioactive compounds including (poly)phenols and organosulfur compounds (OSCs). This study aims to assess the effect of in vitro colonic fermentation on fresh and black garlic by determining the transformation of these compounds through ultrahigh-performance liquid chromatography coupled to mass spectrometry with a linear ion trap (uHPLC-LIT-MS). Colonic fermentation had a similar influence on the phenolic content of fresh and black garlic, with total respective decreases of 43.8% and 41.7%. Meanwhile, fermentation resulted in a significant decrease (33%) in OSCs in black garlic. Compounds such as 4-hydroxybenzoic acid, S-allylcysteine (SAC), and methionine sulfoxide were the phenolic compounds and OSCs with the highest concentration in fresh and black garlic after the in vitro fermentation. These compounds, potentially present at the colonic level, might be responsible for the systemic health benefits associated with the consumption of black and fresh garlic.
Keywords: (poly)phenols; colonic fermentation; human microbial metabolism; organosulfur compounds.