NMR‐based metabolomic approach for EVOO from secular olive trees of Apulia region

Abstract

In this work, a first level investigation was carried out to study the extra virgin olive oils (EVOOs) obtained from secular olive trees of Apulia region. Microextracted olive oil samples from selected and genetically characterized olive trees were studied by 1H NMR‐based metabolomic approach and multivariate analysis, according to cultivar and geographic origin, within the Apulia region. The 1H NMR spectra of oils were analyzed by several pattern recognition methods, using both unsupervised (principal component analysis) and supervised (partial least squares discriminant analysis, orthogonal partial least squares discriminant analysis (OPLS‐DA)) statistical techniques. EVOOs obtained from secular olive trees could be easily differentiated by OPLS‐DA not only depending on the used cultivars but also according to their geographical origin within the different districts of the Apulia region, such to justify a larger biodiversity maintenance of Apulia secular germplasm. Therefore, differences in chemical composition and NMR profiles of EVOOs may be explained either by cultivars or geographic areas. Practical applications: About 10% of the genetic olive tree patrimony within the Apulia region consists of the secular olive trees. A recently introduced regional law (No 14 of June 4th, 2007) allows to exploit oil produced from secular olive trees by labeling it with the special mention: “extra virgin oil from the Apulia secular olive trees”. Characterization of extra virgin olive oils obtained from secular trees may be an optimal solution to increase the value for this product and make it available on the market. On the other hand this economic issue is very important to preserve the unique landscape offered by the ancient olive groves of the Apulia region in south east Italy.

Phytochemical profile and antioxidant capacity of virgin olive oil obtained from the olive cultivar <em>‘Roghiani’</em> from different regions of northern Libya

“…So, its nutritional properties are highly valued for their positive effects on human health (Ballus et al, 2014). The chemical composition of VOO consists of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA) (Del Coco et al, 2013). MUFA was essentially attributed to decreased endothelial activation, and LDL susceptibility to oxidation (Dabbou et al, 2011).…”

Beneficial mycorrhizal symbionts affecting the production of health‐promoting phytochemicals

“…Since recent studies on flavan‐3‐ol and flavanone isomers reported that isomeric forms may show different functional activities , the need of molecular structures elucidation of bioactive metabolites prompted research aimed at improving NMR‐based techniques and softwares analyzing NMR spectra. Moreover, food metabolomics NMR‐based studies allowed metabolic profiling, useful for nutraceutical characterization and traceability of products, using rather simple preparation procedures . However, extended databases of reference compounds NMR spectra are still needed to identify a wide range of metabolites by NMR analyses .…”

Tunisian Extra Virgin Olive Oil Traceability in the EEC Market: Tunisian/Italian (Coratina) EVOOs Blend as a Case Study

“…Moreover, the need of a scientific tool to assess EVOOs geographical origin represents a hot topic issue since the European Regulation 182 of 6 March 2009-which declared the compulsory labeling of EVOOs with the geographical origin of the olives in all European countries [18]-still lacks an official validation methodology. We are currently involved in several NMR based metabolomics and chemometric studies to assess cultivar composition and geographical areas origin of extra virgin olive oils [19][20][21][22][23][24][25]. In this work we focused on a methodological 1 H-NMR spectroscopy coupled with a chemometrics approach in order to provide a quantitative blend composition assessment.…”

“…In particular, we build a specific 1 H-NMR spectral database with blends of a typical Apulian oil obtained from the popular cultivar Coratina [20,25,26], and a widely available Tunisian oil (obtained from Chemlali and Chetoui cultivars) at different known Coratina/Tunisian percentage composition. The relation obtained between the 1 H-NMR based metabolic profiles of the reference blends (accounting for their overall molecular content) and their content could be used as a tool to evaluate the blend composition in analogous possible test samples.…”