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Despite the economic importance and the diffusion of grapevine cultivation worldwide, little is known about leaf chemical composition. We characterized the phenolic composition of Nebbiolo, Barbera, Pinot noir, Cabernet Sauvignon, Grenache, and Shiraz (Vitis viniferaL.) healthy leaves (separating blades and veins) during the season. Quantitative and qualitative differences were found between leaf sectors and among genotypes. In healthy grapevine leaves, anthocyanins, dihydromyricetin-rhamnoside, hexosides of dihydroquercetin, and dihydrokaempferol exclusively accumulated in veins. Astilbin was the only flavanonol detected in blades and the prevalent flavanonol in veins. Barbera distinguished for the lowest proanthocyanidin and the highest hydroxycinnamate content, and Pinot noir for the absence of acylated-anthocyanins. Nebbiolo, and Cabernet Sauvignon displayed a high concentration of epigallocatechin gallate in veins. Nebbiolo leaves showed the highest concentrations of flavanonols and the widest profile differentiation. Knowledge derived from the present work is a contribution to find out leaf polyphenol potential as a part of grapevine defense mechanisms and to dissect genotype-related susceptibility to pathogens; moreover, it represents a starting point for future deepening about grapevine and vineyard byproducts as a source of bioactive phenolic compounds.

Salvia officinalisL. (Sage) is an important industrial plant used both for food and pharmaceutical purposes. The terpene fraction of this plant, which contains thujones and other mono and sesquiterpenoids, is responsible for many of its therapeutic and culinary properties. We used two extraction methods [hydrodistillation (HD) to obtain the essential oil (EO), and supercritical CO2extraction (SFE)] to analyze by gas chromatography–mass spectrometry (GC–MS) the terpene fraction extracted from sage dried leaves. α-Thujone, β-thujone and other oxygenated monoterpenes (1,8-cineole, linalool, camphor, borneol and bornyl acetate) as well as hydrocarbon (β-caryophyllene and α-humulene) and oxygenated sesquiterpenes (caryophyllene oxide, viridiflorol, humulene epoxide II and III) were found. The EO contained a significantly (p < 0.05) higher percentage of 1,8-cineole (10.4%), α-thujone (17.3%) and camphor (29.2%), whereas supercritical fluid (SF) extracts contained a significantly higher percentage of borneol (8.4%), bornyl acetate (2.2%), α-humulene (6.4%), viridiflorol (22.1%), humulene epoxide II and III (2.4% and 0.4%), and some unidentified sesquiterpene alcohols. Both EO and SF extracts contained equal amounts of β-thujone (4.8%) and β-caryophyllene (~7%). Our results show that HD of EO is a more efficient and economic method for α- and β-thujone extraction.

Ocimum basilicum(sweet basil) is an important essential oil plant used for different purposes (from food flavoring to pharmaceutical applications) characterized by the presence of several chemotypes. Here we show a comparative analysis between hydrodistillation of essential oils (EO) and supercritical CO2extraction (SFE) of an O. basilicumchemotype particularly rich in T-cadinol. SFE yielded a higher percentage of 1,8-cineole (10%; 4-fold), linalool (23.2%; 5.8-fold), eugenol (13.3%; 1.2-fold) and germacrene D (5.6%; 28-fold) with respect to EO. On the other hand, EO composition was characterized by higher percentages of T-cadinol (27.5%; 3-fold) and some other sesquiterpenes with respect to SFE. The presence of high percentages of T-cadinol in EO is of great importance owing to the biological activity of this compound in cancer therapy and as an antibiotic.