Angiotensin I-converting enzyme (ACE) inhibition and biological activities of green and black tea samples from Azorean Camellia sinensis

Abstract

The inhibition of ACE can be targeted in order to control hypertension and much attention has recently been paid towards the search for natural products as alternatives to synthetic drugs due to their adverse side effects associated with them. Camellia sinensis tea has received considerable attention due to the beneficial effects on health, particularly as a result of its antioxidant properties. The objective of this study was to investigate the ACE-inhibition of different types of Azorean C. sinensis tea samples and consequently its ability to reduce hypertension, relating it to antioxidant activity, catechin profiles, total phenolic content (TPC) and total flavonoid content (TFC) in different seasons. The results clearly highlighted differences in ACE-inhibition, FRSA, FRAP, FIC activity, TPC and epicatechin content among samples and the best results were observed in green tea collected in the summer. For TFC, higher values were observed in black tea harvested during the summer. In conclusion, the differences are related to the effect of collecting seasons, with the higher values being found in the summer with respect to the spring season.

Keywords

• Anti-hypertensive effects
• Biological activities
• Antioxidants
• Catechins
• Phenolic and flavonoid contents
• Camellia sinensis tea samples