We report the determination of phenolic compounds in olive leaves by reversedphase
HPLC/DAD, and the evaluation of their in vitro activity against several
microorganisms that may be causal agents of human intestinal and respiratory tract
infections, namely Gram positive (Bacillus cereus, B. subtilis and Staphylococcus aureus),
Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Klebsiella
pneumoniae) and fungi (Candida albicans and Cryptococcus neoformans). Seven phenolic
compounds were identified and quantified: caffeic acid, verbascoside, oleuropein, luteolin
7-O-glucoside, rutin, apigenin 7-O-glucoside and luteolin 4’-O-glucoside. At low
concentrations olive leafs extracts showed an unusual combined antibacterial and
antifungal action, which suggest their great potential as nutraceuticals, particulalry as a
source of phenolic compounds.
