Variation Patterns of Mung Bean Polyphenols during Cooking Processes and Their Regulatory Effects on Heat Stress-induced Apoptosis in Caco-2 Cells

This study extracted polyphenols from mung beans subjected to varying cooking times and subsequently determined their total polyphenol content, antioxidant activity, and individual phenolic profile. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting techniques were used to investigate the effect of polyphenols extracted from mung bean on apoptosis induced by heat stress. The results showed that mung beans cooked for 25 min yielded polyphenols with the highest content (16.017 mg/g) and antioxidant capacity (DPPH: 90.733%; ABTS+: 89.997%; T-AOC: 90.423 U/mL). Consequently, this extract was selected for all subsequent experiments. Compared with heat stress group (HS), polyphenols extracted from mung bean after cooking for 25 min could significantly inhibit the mRNA (1.336, 1.319, 1.354) of heat shock proteins (Hsp27, Hsp70, Hsp90) and apoptotic protein expression (Bax: 1.212) (PBCL-2 (0.976) and Bcl-2 (0.696) were increased, while the expressions of CYCS (1.323), CASP3 (1.496), PARP1 (1.208) and related proteins were decreased. The results indicated that the effect of polyphenols extracted from mung bean boiled for 25 min on the prevention of heat stress was greater than the relief effect. After boiling mung bean for 25 min, polyphenols extracted from mung bean reduced intracellular ROS content, regulated HSP27 (HS: 1.015, NAC (ROS inhibitor): 0.832, Pro-mbp+NAC: 0.482, Rem-mbp+NAC: 0.697), HSP70 (HS: 1.013, NAC: 0.856, Pro-mbp+NAC: 0.497, Rem-mbp+NAC: 0.732), and HSP90 (HS: 1.016, NAC: 0.873, Pro-mbp+NAC: 0.501, Rem-mbp+NAC: 0.726), confirmed that heat stress-induced apoptosis was related to the mitochondrial pathway mediated by Caspase, thereby inhibiting heat stress-induced apoptosis. This study provides a theoretical basis for further research on the related pathways of heat stress regulation by polyphenols extracted from mung bean.