Identification of potential angiotensin-I-converting enzyme inhibitory components in celery seed using UHPLC-MS and molecular docking

Ultrafiltration was used to isolate CSAE and the fraction with highest in vitro ACE inhibitory activity was used to assess its effects on cell viability, ACE and ET-1 transcript levels of HUVEC. The main components in the isolate were tentatively identified using UHPLC-MS and molecular docking. Results showed that the ACE inhibitory activity of CSAE was significantly enhanced (p < 0.05) after filtrated through a membrane of 5 kDa molecular weight cut-off (the filtrate was coded as FCSAE5). The concentration of FCSAE5 in the range of 10-2-103 mu g/mL had no significant effect on cell viability. ACE and ET-1 mRNA expressions were significantly inhibited (p < 0.05) after the cells being treated with 1 or 10 mu g/mL of FCSAE5. The main components in FCSAE5 were alkaloids, phenolic compounds, carbohydrates, aromatic compounds, amino acids and terpenoids. Molecular docking results suggested that flavonoids, terpenoids and carbohydrates in celery seeds play main roles in the ACE inhibitory activity.