Pimpinella anisum seeds essential oil from Lesvos island: Effect of hydrodistillation time, comparison of its aromatic profile with other samples of the Greek market. Safe use.

The essential oil of Pimpinella anisum L. (Apiaceae) seeds from Lesvos Island (Greece), famous as flavor for the production of the aperitif "ouzo", has been analyzed by GC-MS for the first time. Additionally, three samples of the Greek market originated from North and Central Greece (Thessaly, Viotia) and Turkey, were also analyzed and all of them were compared to the quality limits given in European Pharmacopoeia for medicinal purposes. The effect of hydrodistillation time found to be very important as the results showed differentiations of the oil yield and the chemical content. The most abundant identified metabolites were trans-anethole, γ-himachalene, estragole and pseudoisoeugenyl 2-methylbutyrate. It is noteworthy, that Lesvos anise oil showed the best quality according to European Pharmacopoeia's standards, while it had the highest yield and the richest chemical composition (28 identified compounds) among all studied samples, contributing to the well known quality of "ouzo" from Plomari. Furthermore, two major secondary metabolites from Lesvos' anise oil: trans-anethole and a mixture of himachalenes have been isolated and structurally determined. Moreover, the safe use of anise oil is discussed due to potential toxic effects of estragole.

Optimization of a green extraction method for the recovery of polyphenols from olive leaf using cyclodextrins and glycerin as co-solvents.

Olive leaf, an agricultural by-product, was studied for the valorization of its biophenols using green extraction techniques; i.e. non-toxic and eco-friendly extraction solvents were used, involving water and glycerol. 2-hydroxypropyl-ß-cyclodextrin (CD), was also employed as an enhancer of the extraction, since cyclodextrins (CD's) are known to improve the extractability of olive leaf polyphenols by forming water soluble inclusion complexes. The process was optimized by implementing a central composite (Box-Behnken) experimental design and response surface methodology, taking into consideration the following independent variables: glycerol concentration (Cgl), CD concentration (CCD) and temperature (T). The evaluation of the extraction model was based on two responses: the total polyphenol yield (YTP) and the antiradical activity (AAR). Optimum values for the extraction process were obtained at 60% (w/v) glycerol content, T = 60 °C and 7% (w/v) CD content. LC-MS analysis was also applied in order to characterize the polyphenolic composition of extracts containing cyclodextrins. The main polyphenols present were oleuropein and oleuropein derivatives. Olive leaf aqueous extracts containing glycerol and cyclodextrins may be used as raw materials/ingredients for several end-users in the food, cosmetic and pharmaceutical industries.