The consumption of olive oil, because of its valuable biomolecules content, has been correlated with a reduction of cardiovascular disease and some types of cancer. In fact, its phenolic compounds have positive effects on several physiological parameters, such as oxidative damage and cellular function. The aim of this study was to characterize extra virgin olive oils from several regions of the Italian territory, produced by using different cultivars as well as cultivation and production techniques, through the evaluation of their phenolic content and anti-oxidant activity. Specifically, the phenols extraction yield, the total phenolic and ortho-diphenolic contents, and the anti-oxidant activity of the phenolic extracts were measured. Furthermore, the following compounds were detected and quantified by RP-HPLC analysis: hydroxytyrosol, tyrosol, para-coumaric acid, ortho-coumaric acid and trans-cinnamic acid. Two different extraction procedures were compared: by using the mixture CH3OH 70% / HCl 1%, the phenols extraction yield was 7-fold higher than that obtained by CH3OH 80%. The amounts of total phenols, ortho-diphenols, and specific bioactive molecules showed wide variability among both oils from different Italian regions and oils produced in the same district, thus indicating that different factors such as cultivar and pedo-climatic conditions can influence the olive oil composition, and its nutritional and healthy properties. The anti-oxidant power of the phenolic extracts was investigated by evaluating their protective capacity against oxidative stress in erythrocytes. TBARS (Thiobarbituric Acid Reactive Substances) and meta-hemoglobin levels were chosen as markers of protection against erythrocyte damages. In particular, a reduction of TBARS and meta-hemoglobin contents was observed in stressed red blood cells pre-treated with phenolic extracts. These results demonstrated that it is possible to characterize extra virgin olive oils from different Italian regions through their phenolic content and their radical-scavenging activity.
Characterization of Italian extra virgin olive oils and evaluation of their protective effect against oxidative stress
G del Monaco;A Morana;E Ionata;L Maurelli;L Marcolongo;F La Cara
2013
Abstract
The consumption of olive oil, because of its valuable biomolecules content, has been correlated with a reduction of cardiovascular disease and some types of cancer. In fact, its phenolic compounds have positive effects on several physiological parameters, such as oxidative damage and cellular function. The aim of this study was to characterize extra virgin olive oils from several regions of the Italian territory, produced by using different cultivars as well as cultivation and production techniques, through the evaluation of their phenolic content and anti-oxidant activity. Specifically, the phenols extraction yield, the total phenolic and ortho-diphenolic contents, and the anti-oxidant activity of the phenolic extracts were measured. Furthermore, the following compounds were detected and quantified by RP-HPLC analysis: hydroxytyrosol, tyrosol, para-coumaric acid, ortho-coumaric acid and trans-cinnamic acid. Two different extraction procedures were compared: by using the mixture CH3OH 70% / HCl 1%, the phenols extraction yield was 7-fold higher than that obtained by CH3OH 80%. The amounts of total phenols, ortho-diphenols, and specific bioactive molecules showed wide variability among both oils from different Italian regions and oils produced in the same district, thus indicating that different factors such as cultivar and pedo-climatic conditions can influence the olive oil composition, and its nutritional and healthy properties. The anti-oxidant power of the phenolic extracts was investigated by evaluating their protective capacity against oxidative stress in erythrocytes. TBARS (Thiobarbituric Acid Reactive Substances) and meta-hemoglobin levels were chosen as markers of protection against erythrocyte damages. In particular, a reduction of TBARS and meta-hemoglobin contents was observed in stressed red blood cells pre-treated with phenolic extracts. These results demonstrated that it is possible to characterize extra virgin olive oils from different Italian regions through their phenolic content and their radical-scavenging activity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
