Chemical composition and thermal properties of Tunisian pecan nut [Carya illinoinensis (Wangenh.) K. Koch] oils

An investigation on fatty acid, triacylglycerol, tocopherol, and xanthophyll contents and thermal properties of pecan (Carya illinoinensis) kernel oils from two cultivars was carried out. The main fatty acids were oleic acid, followed by linoleic and palmitic acids. The predominant triacylglycerols were OOL, OOO, and OLL (where O stands for oleoyl and L for linoleoyl). Pecan kernel oil is a rich source of tocopherols, mainly γ-tocopherol. Two xanthophylls (lutein and zeaxanthin) were investigated, and lutein was found to be the major one. Thermal behavior was studied by differential scanning calorimetry (DSC). Pecan nut oil displayed melting and crystallization transitions at low-temperature zones. The difference between DSC parameter values provides a path for distinguishing among cultivars. These data promote pecan kernel oil as a potential source of bioactive compounds with nutraceutical properties (monounsaturated fatty acids, tocopherols, and xanthophylls) and reveal, for the first time, the thermal properties of Carya illinoinensis oil.

Composition and characterization by GC-MS of the essential oil extracted from

Fresh leaves of N. glauca were collected from the northern region of Tunisia. The leaves were submitted to water distillation for 4 h, using a Clevenger-type apparatus. The obtained essential oils were dried over anhydrous sodium sulphate and after filtration, stored at 4 °C until use. The chemical composition of the isolated essential oil was analyzed by gas chromatography–mass spectrometry (GC–MS). Eighteen compounds were identified: eugenol, the major compound in the essential oil, was present at a high level (58.49%), followed by nonadecane, eugenyl acetate and tridecane, 3-methyl at 6.38; 5.57 and 5.19%, respectively. The percentage of compounds dodecane, 2, 6, 11 trimethyl, tetradecane, docosane, tricosane and 1, 2-benzene dicarboxilic, dibutyl ester varied between 1 and 2%; whereas the other compounds (including limonene, and saturated hydrocarbons) remained at low percentages, not exceeding 1%. This study could be very useful for the characterization, pharmaceutical and therapeutic applications of the essential oil from N. glauca.

Highly efficient modified lead oxide electrode using a spin coating/electrodeposition mode on titanium for electrochemical treatment of pharmaceutical pollutant

In this study, Ti/TiO₂/PbO₂ anodes consisting of a PbO₂ coating growth on the TiO₂ interlayer deposited on titanium substrates were prepared combining different deposition technics: electrochemical method using anodization (Anod), electrodeposition (EL), and sol gel spin coating (SG). Different kinds of anodes have been tested for the removal of ampicillin, a pharmaceutical pollutant, from water. The structure and the surface morphology of the prepared multiple coatings were characterized by scanning electron microscopy and Energy-Dispersive X-ray spectroscopy respectively. Electrochemical impedance spectroscopy was also investigated in order to study the electrocatalytic activity of the anodes. The performance of the electrodes was evaluated through high performance liquid chromatography and chemical oxygen demand (COD) measurements. It was noticed that ampicillin could be mineralized by anodic oxidation process using Ti/TiO₂/PbO₂ anodes. The best results were obtained for Ti/TiO₂^SG/PbO₂^EL as anode with a 64% of COD removal after 300 min of treatment and a fast decrease in the amount of ampicillin was reached after almost one hour. Experimental results demonstrate that Ti/TiO₂^SG/PbO₂^EL anode presents the best ability for the degradation of ampicillin through anodic oxidation compared to the Ti/TiO₂^SG/PbO₂^SG and Ti/TiO₂^Anod/PbO₂^EL electrodes.

Chemical characterization and thermal properties of kernel oils from Tunisian peach and nectarine varieties of

A comparative study was conducted to determine the fatty acids, triacylglycerol compositions and thermal properties of Tunisian kernel oils from the Prunus persica varieties, peach and nectarine, grown in two areas of Tunisia, Gabes and Morneg. Qualitatively, the fatty acids composition and triacylglycerol species were identical for all samples. Oleic acid (67.7-75.0%) was the main fatty acid, followed by linoleic (15.7-22.1%) and palmitic (5.6-6.3%) acids. The major triacylglycerol species were triolein, OOO (38.4-50.5%), followed by OOL (18.2-23.2%), POO (8.3-9.7%) and OLL (6.3-10.1%). The thermal profiles were highly influenced by the high content of triolein due to the importance of oleic acid in these oils. Moreover, the fatty acids distribution in TAG external positions was determined as corresponding to an α asymmetry coefficient that was between 0.10 and 0.12, indicating a high asymmetry in the distribution of saturated fatty acids in the position sn-1 and sn-3 in the TAG species of all samples.