Towards biomolecular aided agriculture: metabolic fingerprint of wild and cultivated Sicilian medicinal plants belonging to the folk tradition

Abstract

For chemotaxonomic and agro-technological purposes, extracts of wild thyme (Thymus vulgaris L., 30 samples), oregano (Origanum vulgare L., 61 samples) and rosemary (Rosmarinus officinalis L., 57 samples) collected in different areas of the Sicilian region, as well as cultivated sage (Salvia officinalis L., 7 samples), were screened for their phenolic compound content. All these plants belong to Sicilian culinary tradition and folk remedies. In order to have as many details as possible on the composition of these plants and their variation, extracts of different polarity (lipidic and alcoholic) for each cultivar were obtained and analysed. Several groups of selected molecules, typical of the different species and a part of their secondary metabolism (chemotaxonomical markers), were chosen, containing flavonoids, terpenoids, and organic acids as more representative chemical classes. The markers were firstly identified in the extracts through exhaustive analyses using the LC/UV-DAD/MS technique and then processed with high-throughput HPLC to obtain qualitative and quantitative compositional data. These data, together with the yield of extractions from the vegetable material, provided enough information to build up an analytical matrix from which the best extract in terms of presence and percentage of polyphenols could be selected.