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Spices and aromatic herbs have been used since ancient times for flavor, aroma, color, and preservation of food and beverages. They are a rich source of bioactive and functional ingredients to which numerous food-related properties are associated. Among the active ingredients, essential oils have received particular attention due to their wide array of biological activities including antioxidant, antimicrobial, anti-inflammatory, anti-nociceptive, anti-carcinogenic, and acaricidal activities, among others (Harris, 2010).Essential oils are a complex mixture of volatile organic components contributing the flavor and fragrance of a plant. Among essential oil-bearing plants, more than 400 species are processed for their raw materials and that 75% of these (300 species) are potential producers of commercially used essential oils (Lawrence, 1995).Because of their biological properties, essential oils are widely used in flavor and fragrance, cosmetics, pharmaceutical, food and feed, and household goods industries. Within the food industries, oil flavoring is one of the major application areas of essential oils owing to their antioxidant property and preventing lipid peroxidation capacity

The present study aims to reduce the fluoride concentration of drinking water using a novel mild adsorbent based natural clay. The natural clay was dealuminated/realuminated and dehydroxylated by intense washing and heating processes. The developed adsorbent was confirmed by X-ray diffraction (XRD), thermal analyses (ATD-TG) and nuclear magnetic resonance solid-state with magic angle spinning (MAS NMR). MAS NMR results showed that distorted tetrahedral-Al coordination and penta-Al coordination sites were responsible for fluoride adsorption. Batch adsorption experiments were investigated without any adjustment of water pH. The effect of the clay dosage over the range of 0.5-2 g/50 mL of sample solution was studied. Results revealed that the aggregation of the clay particles in the water was successfully avoided thanks to the heating process. Kinetics and adsorption isotherms were also investigated. The adsorption equilibrium was achieved on a timescale of seconds. Adsorption kinetics data followed pseudo-first-order as well as pseudo-second-order models while isotherm experimental data followed the Freundlich model. The maximum adsorption capacity was relatively small (1.2 mg•g −1 ). Tests performed on Tunisian contaminated drinking water showed that water potability with respect to fluoride was successfully achieved; suggesting that the dealuminated/realuminated dehydroxylated clay can be a promising fluoride adsorbent for drinking water.

The decomposition of penicillin G and erythromycin antibiotics at concentration of 0.2 mg ml(-1) by gamma irradiation at 50 kGy followed by biological treatment with Cupriavidus metallidurans CH34 was evaluated. Degradation of penicillin G and erythromycin was analyzed using nuclear magnetic resonance analysis (NMR), fourier transform infrared spectroscopy (FTIR), and chemical oxygen demand (COD). The exposure to the absorbed dose of 50 kGy caused degradation of penicillin G and erythromycin in the aqueous solution. The complete disappearance of NMR and FTIR peaks following irradiation confirmed the breakage of the β-lactam ring in penicillin G, and the decarboxylation and cleavage of the thiazolidine ring and for erythromycin, the complete destruction of the three aromatic rings. Irradiation alone removed 52.8 and 65.5 % of penicillin G and erythromycin, respectively. Further reduction to 12.6 and 14 % of the original penicillin G and erythromycin COD, respectively, was achieved using treatment of the irradiation products with C. metallidurans.