Hassen Mohamed Sbihi

Evaluation and characterisation of Citrullus colocynthis (L.) Schrad seed oil: Comparison with Helianthus annuus (sunflower) seed oil.

The physicochemical properties, fatty acid, tocopherol, thermal properties, (1)H NMR, FTIR and profiles of non-conventional oil extracted from Citrullus colocynthis (L.) Schrad seeds were evaluated and compared with conventional sunflower seed oil. In addition, the antioxidant properties of C. colocynthis seed oil were also evaluated. The oil content of the C. colocynthis seeds was 23.16%. The main fatty acids in the oil were linoleic acid (66.73%) followed by oleic acid (14.78%), palmitic acid (9.74%), and stearic acid (7.37%). The tocopherol content was 121.85 mg/100g with γ-tocopherol as the major one (95.49%). The thermogravimetric analysis showed that the oil was thermally stable up to 286.57°C, and then began to decompose in four stages namely at 377.4°C, 408.4°C, 434.9°C and 559.2°C. The present study showed that this non-conventional C. colocynthis seed oil can be used for food and non-food applications to supplement or replace some of the conventional oils.

Effects of homogenization process parameters on physicochemical properties of astaxanthin nanodispersions prepared using a solvent-diffusion technique.

Nanodispersion systems allow incorporation of lipophilic bioactives, such as astaxanthin (a fat soluble carotenoid) into aqueous systems, which can improve their solubility, bioavailability, and stability, and widen their uses in water-based pharmaceutical and food products. In this study, response surface methodology was used to investigate the influences of homogenization time (0.5–20 minutes) and speed (1,000–9,000 rpm) in the formation of astaxanthin nanodispersions via the solvent-diffusion process. The product was characterized for particle size and astaxanthin concentration using laser diffraction particle size analysis and high performance liquid chromatography, respectively. Relatively high determination coefficients (ranging from 0.896 to 0.969) were obtained for all suggested polynomial regression models. The overall optimal homogenization conditions were determined by multiple response optimization analysis to be 6,000 rpm for 7 minutes. In vitro cellular uptake of astaxanthin from the suggested individual and multiple optimized astaxanthin nanodispersions was also evaluated. The cellular uptake of astaxanthin was found to be considerably increased (by more than five times) as it became incorporated into optimum nanodispersion systems. The lack of a significant difference between predicted and experimental values confirms the suitability of the regression equations connecting the response variables studied to the independent parameters.

Garden cress (Lepidium sativum Linn.) seed oil as a potential feedstock for biodiesel production

Lepidium sativum L. (garden cress) is a fast growing annual herb, native to Egypt and west Asia but widely cultivated in temperate climates throughout the world. L. sativum seed oil (LSO) extracted from plants grown in Tunisia was analyzed to determine whether it has potential as a raw material for biodiesel production. The oil content of the seeds was 26.77%, mainly composed of polyunsaturated (42.23%) and monounsaturated (39.62%) fatty acids. Methyl esters (LSOMEs) were prepared by base-catalyzed transesterification with a conversion rate of 96.8%. The kinematic viscosity (1.92 mm(2)/s), cetane number (49.23), gross heat value (40.45), and other fuel properties were within the limits for biodiesel specified by the ASTM (American Standard for Testing and Materials). This study showed that LSOMEs have the potential to supplement petroleum-based diesel.

Characterization of White Mahlab (Prunus mahaleb L.) Seed Oil: A Rich Source of α‐Eleostearic Acid

UNLABELLED Seed oils with high polyunsaturated fatty acid content are used in various industries including the food and pharmaceutical industries. White mahlab (Prunus mahaleb L.) seed was found to contain 31% oil. The oil was highly polyunsaturated and abundant in α-eleostearic (38.32%), oleic (31.29%), and linoleic (22.96%) acids, which together comprised 93.91% of the total fatty acids. The α-eleostearic acid was identified and characterized based on (1)H-NMR, UV, and FTIR spectroscopy. The oil was characterized by a relatively high quantity of tocopherols with γ-tocopherol as the major tocopherol isomer. The physicochemical characteristics of the white mahlab seed and seed oil were also determined. The thermogravimetric analysis indicated that the oil was thermally stable up to 350 °C and began to decompose at 520 °C. This study demonstrated that these seeds may be reused and their oil incorporated into other food products, a beneficial practice considering that the compounds present in the seeds and oils have positive effects on human health. PRACTICAL APPLICATION In this study, mahlab seed oil was found to have potentials to become a new edible oil source as it contained a high level of polyunsaturated fatty acids especially, α-eleostearic acid, which is a conjugated fatty acid rarely found in vegetable oils and has a beneficial effects on human health.

Preparation of Astaxanthin Nanodispersions Using Gelatin-Based Stabilizer Systems

The incorporation of lipophilic nutrients, such as astaxanthin (a fat soluble carotenoid) in nanodispersion systems can either increase the water solubility, stability and bioavailability or widen their applications in aqueous food and pharmaceutical formulations. In this research, gelatin and its combinations with sucrose oleate as a small molecular emulsifier, sodium caseinate (SC) as a protein and gum Arabic as a polysaccharide were used as stabilizer systems in the formation of astaxanthin nanodispersions via an emulsification-evaporation process. The results indicated that the addition of SC to gelatin in the stabilizer system could increase the chemical stability of astaxanthin nanodispersions significantly, while using a mixture of gelatin and sucrose oleate as a stabilizer led to production of nanodispersions with the smallest particle size (121.4 ± 8.6 nm). It was also shown that a combination of gelatin and gum Arabic could produce optimal astaxanthin nanodispersions in terms of physical stability (minimum polydispersity index (PDI) and maximum zeta-potential). This study demonstrated that the mixture of surface active compounds showed higher emulsifying and stabilizing functionality compared to using them individually in the preparation of astaxanthin nanodispersions.

Chamaerops humilis L. var. argentea André date palm seed oil: a potential dietetic plant product.

Chamaerops humilis L. var. argentea André (C. humilis) date palm seeds are an underutilized source of vegetable oil, and no studies describing their physicochemical characteristics to indicate the potential uses of this seed or seed oil have been reported. The oil content of the seeds is about 10%, mainly composed of oleic acid (38.71%), lauric acid (21.27%), linoleic acid (15.15%), palmitic acid (9.96%), and stearic acid (7.17%). The tocol (tocopherols and tocotrienols) content is 74 mg/100 g, with δ-tocotrienol as the major contributor (31.91%), followed by α-tocotrienol (29.37%), γ-tocopherol (20.16%), and γ-tocotrienol (11.86%). Furthermore, this oil shows high thermal stability. The differential scanning calorimetery curves revealed that the melting and crystallization points are 9.33 °C and -15.23 °C, respectively.

Characterization of Hachi (Camelus dromedarius) fat extracted from the hump.

In this work, the characteristics of fat from the hump of young camels (Hachi) were evaluated. The physicochemical properties of the fat were as follows: melting point, 45°C; saponification value, 202.3 mg KOH/g oil; refractive index (60°C), 1.468; unsaponifiable matter, 1.37%; free fatty acids (as the percentage of oleic acid), 0.96%; and peroxide value, 3.37 mequiv. O2/kg oil. High-resolution (1)H nuclear magnetic resonance ((1)H NMR) was used for the direct determination of the iodine value of Hachi fat (62.74 g/100 g oil). The Hachi fat was composed primarily of oleic acid (33.35%), followed by palmitic acid (26.16%), stearic acid (10.07%), palmitelaidic acid (9.56%) and myristic acid (8.83%). The thermal properties were assessed by thermogravimetry (TG) and derivative thermogravimetry (DTG). The results of the present analytical study showed that Hachi fat could be used in food products and as an important source of biological materials.

A Cadmium Coordination Polymer Based on Phosphate Clusters: Synthesis, Crystal Structure, Electrochemical Investigation and Antibacterial Activity

Abstract A new d10 coordination polymer,

A direct synthetic route to allyl sulfides from cyclic Morita–Baylis–Hillman alcohols

\left\{ {\left( {{\text{C}}_{5} {\text{H}}_{14} {\text{N}}_{2} } \right)_{2} \left[ {{\text{Cd}}\left( {\left( {{\text{P}}_{6} {\text{O}}_{18} } \right)\left( {{\text{H}}_{2} {\text{O}}} \right)_{2} } \right)} \right] \cdot 6{\text{H}}_{2} {\text{O}}} \right\}_{n}