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Abstract: The effects of a long storage period on some Tuscan EVOOs filtered and frozen at −23°C in comparison with the same specimens maintained at room temperature in the dark, were evaluated by monitoring the evolution of their phenolic composition and aromatic profile.The oils were analyzed immediately after opening and after 10days up to 18months after oil bottling. A non parametric statistical analysis and principal components analysis (PCA) coupled to linear discriminant analysis (LDA) was applied for assessing the differences among the trials. Increments in tyrosol, hydroxytyrosol and % of hydrolysis were observed for EVOOs stored at room temperatures starting from 3-months storage, and increased thereafter. The frozen EVOOs were statistically undistinguishable over time, differently from the correspondent ones at room temperature. All the frozen EVOOs showed negligible differences in aromatic profile until 12month of storage. Some compounds potentially related to off-odor sensations were significantly increased in the unfrozen specimens only at 18months. [Copyright &y& Elsevier]

Virgin olive oil is a typical component of the Mediterranean diet, consumed unrefined and rich in important molecules, such as minor polar compounds (hydroxytyrosol, tyrosol, secoiridoids and flavonoids) and fatty acids. These molecules not only influence the sensorial properties of both olives and virgin oil but they are also important markers for typicity, biodiversity and quality determination of this product. The aim of this study was to evaluate the minor polar compound and fatty acid contents of 10 monocultivar virgin olive oils, typical of Tuscany, in order to have better knowledge about the quali-quantitative profiles of these compounds in samples obtained from both the same collecting season and same processing technique. Quali-quantitative analysis (performed by HPLC/DAD, HPLC/MS and GC) could be a useful tool to better correlate the typicity of the virgin olive oil with its minor polar compound and fatty acid pattern. Further studies are in progress to isolate the unknown compounds and to further investigate the quality index of this food product. [Copyright &y& Elsevier]

Graphical abstract Highlights • Honey extracts inhibit the activity of protein tyrosine phosphatase 1B (PTP1B). • Chronic treatment with honey extracts enhances the expression of insulin receptor in liver cells. • Treatment of liver cells with honey extracts increases glucose uptake by cells. • Fast NMR analysis can be used to identify honey with anti-hyperglycaemic activity. Abstract Honey is a food known for its medical properties. In this work, we have studied the impact of different types of honey on insulin signalling pathway. We found that honey extracts inhibit the enzyme PTP1B, one of the main negative regulators of insulin receptor signalling. HPLC-MS analysis allowed us to confirm the presence of several natural PTP1B inhibitors in the honey extracts analysed. Statistical analysis methods show a correlation between specific 1H-NMR resonance frequencies/HPLC peaks and the inhibitory power of the samples. This finding will allow the prediction of the biological properties of honey samples applying relative simple analytical methods. Finally, we demonstrated that the treatment of HepG2 cells with honey extracts enhances the expression of insulin receptor, and stimulates glucose uptake. For the first time, our results demonstrate that bioactive components of honey could improve glycaemic control by both inhibiting PTP1B and stimulating the expression of insulin receptor in liver cells. [ABSTRACT FROM AUTHOR]

An original kinetic study of the transformation phenomena of phenolic compounds in olive paste was carried out at different malaxation time-temperature conditions under exposure to air, using Abencor lab equipment to process olives (Frantoio cv) of a known degree of ripeness. Empirical kinetic models and the relevant apparent kinetic constants were determined for the following significant indices: total phenolic compound content in waste water samples using the Folin-Ciocalteu method; verbascoside and β-OH-verbascoside contents in olive paste samples using HPLC; and 3,4-DHPEA-EDA contents in olive oil samples using HPLC. Two opposite phenolic compound transformation phenomena were proposed to explain the kinetic models: (i) enzymatic oxidative damage of phenolic compounds; (ii) physical and enzymatic release of phenolic compounds from cellular tissues. It was possible to propose a reference optimization chart to predict “selective” time-temperature conditions to maximize the apparent EVOO extraction yield while minimizing the degradation phenomena of phenolic compounds during malaxation. [ABSTRACT FROM AUTHOR]

Abstract: The metabolic profile of secondary products in calli and cell suspension cultures of Camptotheca acuminata Decaisne was investigated and compared to that of the leaves and roots taken from the plant. Neither in vitro system produced the anticancer quinoline alkaloid camptothecin (CPT); they accumulated discrete quantities of polyhydroxylated triterpenoids, different from those found in the plant organs, and ellagic acid derivatives. Nine ellagic acid derivatives (1a–1d and 2a–2e) and eight triterpenoid acids (3a–3e and 4a–4c) were isolated and characterised. All the identified triterpenes were related to ursane- or oleanane-type skeletons and their concentrations rose to 4.5% in suspended cells. [Copyright &y& Elsevier]