The bioaccessibility and bioactivity of polyphenols from tsampa prepared from roasted highland barley flour solid-fermented by autochthonous lactic acid bacteria.

Tsampa, which is abundant in polyphenols, demonstrates significant bioactivity and potential health benefit. However, the bioaccessibility and potential bioactivity of polyphenols derived from tsampa prepared from autochthonous lactic acid bacteria solid-fermented roasted highland barley flour (F-RHBF) have not been investigated. This study aimed to evaluate the bioaccessibility and bioactivity of polyphenols from tsampa prepared from F-RHBF through in vitro digestion model, and additionally, to explore the protective effects of digested tsampa extract against oxidative stress damage by establishing HO -induced oxidative stress injury model of HepG cells. The results indicated that tsampa prepared from F-RHBF exhibited excellent bioaccessibility and bioactivity of polyphenols, including antioxidant and digestive enzymes inhibitory activity, compared to tsampa prepared from unfermented RHBF (UF-RHBF). Furthermore, the digested extract of tsampa prepared from F-RHBF was more effective in protecting HepG cells from oxidative damage by reducing the level of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activity of superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx), and total antioxidant capacity (T-AOC). These findings suggested that fermentation and in vitro digestion can improve the bioaccessibility and bioactivity of polyphenols from tsampa. Present findings pave the way toward applying fermented highland barley flour to design tsampa and novel functional foods.