Calabrian extra-virgin olive oil from Frantoio cultivar: chemical composition and health properties
Extra virgin olive oil (EVOO) plays a crucial role in the Mediterranean diet. Recently, attention has been focused on presence in EVOO of phenolic compounds, phytochemicals characterized by a series of healthy properties. This paper analyzed the phenolic profile, the inhibitory activity against carbohydrate hydrolising enzyme as well as the radical scavenging activity of EVOO obtained from Olea europea L. cv. Frantoio. Samples derived from fruits collected in four different areas: Cariati, Vaccarizzo Albanese, Montalto Uffugo, and Praia a Mare. The phenolic profile obtained by HPLC revealed the presence of hydroxytyrosol (3,4-DHPEA, between 1.2 and 5.3 mg/kg) and p-hydroxyphenylethanol or tyrosol (p-HPEA, between 1.1 and 5.4 mg/kg), as the main components. Secoiridoids and their derivatives were also found in high concentrations (3,4-DHPEA-EDA 50.3-98.4 mg/kg, p-HPEA-EDA 34.6-52.9 mg/kg). All samples showed carbohydrate-hydrolyzing enzymes inhibition. The most promising activity was observed with EVOO from Vaccarizzo Albanese (IC50 of 65.5 and 57.7 µg/ml against α-glucosidase and α-amylase, respectively). The same sample showed the highest antioxidant activity of 45.3 and 56.3 µg/ml against DPPH and ABTS radicals, respectively. This sample was richest in phenols. In conclusion, EVOO has high-level bioactive compounds and a promising antioxidant and hypoglycemic activity.