Oleuropein

The primary bioactive polyphenol in olive leaves. RCTs using olive leaf extract standardized to oleuropein show modest blood pressure reduction in pre-hypertensive subjects and improved endothelial function. Anti-inflammatory and antimicrobial properties demonstrated in vitro. Verbascoside (acteoside) is a related phenylpropanoid often co-extracted with oleuropein from olive fruit/leaf — similar antioxidant profile. Bioavailability is moderate; extensively metabolized after absorption.