Bioactive minor components of Italian and Extra-European hemp seed oils

Abstract

Nowadays, hempseed oil is well known for its nutritional and health benefits. In this work, a study of unsaponifiable fraction of hemp seed oils (HSO) paying particular attention to the qualitative and quantitative analysis of sterols, aliphatic alcohols, and tocopherols, as well as to carotenoid, and chlorophyll contents. Samples were of Italian (IT) and Extra-European (EE) origin. β-sitosterol was the predominant phytosterol, followed by campesterol, as obtained by high-resolution gas chromatography (HRGC). Moreover, high-performance liquid chromatography (HPLC) analysis with fluorescence detection method was carried out to analyze tocopherol fraction. The results showed high levels of vitamin E vitamers, with prevalence of γ-isomer of tocopherols. Some significant differences (p < 0.05) were detected between IT and EE samples for some bioactive compounds as α- and γ-tocopherols, and chlorophyll contents. Principal component analysis, applied to unsaponifiable fraction data, in particular sterols and tocopherols, has highlighted the ability to discriminate the HSO samples from EE samples. These results are promising and suggest that HSO minor components might be used as geographical markers, after the investigation of a large number of samples.