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Optimization of conditions for anthocyanin hydrolysis from red wine was investigated using response surface methodology. The aglycon forms of the anthocyanins were quantified by high-performance liquid chromatography with diode array detection. The combined effects of three independent variables, HCl amount, heating temperature, and hydrolysis time, were studied using a 2(3) full-factorial central composite design. Anthocyanin hydrolysis yield depended mainly on the heating temperature and time of hydrolysis. HCl amount was the factor that least influenced the hydrolysis of anthocyanins. From experimental results, the maximum yield of anthocyanidins was reached with 9.8 mL of HCl (32% v/v), a heating temperature of 166.2 °C, and a hydrolysis time of 46.6 min. Five anthocyanidins, namely, delphinidin, cyanidin, petunidin, peonidin, and malvidin, were quantified in red wine. The reliability of the method was confirmed by recovery experiments, performed under optimal conditions. Recoveries indicated that anthocyanidins resisted the hydrolysis conditions.

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Bisphenol A (BPA) is an endocrine disrupting chemical (EDC) whose migration from food packaging is recognized worldwide. However, the real overall food contamination and related consequences are yet largely unknown. Among humans, children's exposure to BPA has been emphasized because of the immaturity of their biological systems. The main aim of this study was to assess the reproductive impact of BPA leached from commercially available plastic containers used or related to child nutrition, performing ecotoxicological tests using the biomonitoring species Daphnia magna. Acute and chronic tests, as well as single and multigenerational tests were done. Migration of BPA from several baby bottles and other plastic containers evaluated by GC-MS indicated that a broader range of foodstuff may be contaminated when packed in plastics. Ecotoxicological test results performed using defined concentrations of BPA were in agreement with literature, although a precocious maturity of daphnids was detected at 3.0 mg/L. Curiously, an increased reproductive output (neonates per female) was observed when daphnids were bred in the polycarbonate (PC) containers (145.1±4.3 % to 264.7±3.8 %), both in single as in multigenerational tests, in comparison with the negative control group (100.3±1.6 %). A strong correlated dose-dependent ecotoxicological effect was observed, providing evidence that BPA leached from plastic food packaging materials act as functional estrogen in vivo at very low concentrations. In contrast, neonate production by daphnids cultured in polypropylene and non-PC bottles was slightly but not significantly enhanced (92.5±2.0 % to 118.8±1.8 %). Multigenerational tests also revealed magnification of the adverse effects, not only on fecundity but also on mortality, which represents a worrying trend for organisms that are chronically exposed to xenoestrogens for many generations. Two plausible explanations for the observed results could be given: a non-monotonic dose-response relationship or a mixture toxicity effect.

The rising of global per capita food consumption has driven scientists and manufacturers into a search for new or renewed edible oil sources, while also improving their production towards maximum yield, quality, and economic feasibility. Hence, a new origin (Algerian) of Moringa oleifera seed oil was characterized in the present study in terms of its physical and chemical features on two consecutive crops. Moreover, aiming to ascertain if the industrial solvent extraction could be enhanced, extracted oils from shelled and unshelled seeds were compared. All oils under study presented a low oxidation status and an excellent resistance to oxidation. Additionally to the characteristic high average content of unsaturated fatty acids (71% oleic acid), microcomponent analyses revealed interesting amounts of phytosterols (4–5 g/kg), tocopherols (287–327 mg/kg), carotenoids (4–8 mg/kg), and phenolic compounds (11–17 mg/kg). These outcomes were within or better (stability and oxidative status) than reported data for M. oleifera seed oil from other origins, and without significant differences between crops. Apart from a slight color change and increased sterol and wax contents when extracted with shells, no other significant compositional changes were observed, including oil extraction yield, both equivalent to 37% on a kernel basis. This work sustains the high quality of Algerian M. oleifera seed oil, a still underutilized crop in this country. Also, it provides an insight on the potential use of grinded whole seeds directly for solvent extraction, reducing labor demand and cost for the industries, without significant variation on compositional and stability parameters. Practical applications: Regarding the growing demand on edible oils, and considering Algeria as a country with a large range of climatic conditions, M. oleifera cultivation for edible oil extraction could be of economic interests to the region. Based on the findings of this work, the oil extracted from M. oleifera grown in Algeria presents significantly high quality, stability, and consistency between crops. From a technological point of view, we also propose that solvent extraction can be performed directly on the powder of whole M. oleifera seeds, avoiding the shelling step, with proportional oil yield and equivalents quality, of major importance for the industry. Algerian Moringa oil presents high quality, stability, and consistency between crops. The presence of shells does not effect oil quality and yield, of major importance for the industry.

In the present work, an experimental study on the performance of an “in-house”-developed proton-exchange membrane (PEM) fuel cell with 25 cm2 of active membrane area is described. The membrane/electrodes assembly (MEA), from Paxitech, has seven layers [membrane/catalyst layers/gas diffusion layers (GDLs)/gaskets]. The catalytic layers have a load of 70% Pt/C and 0.5 mg of Pt/cm2 on both sides, and the membrane is made of Nafion 112. A multiserpentine configuration for the anode and cathode flow channels is used. Experiments were carried out under different anode and cathode relative humidities (RHs) and flow rates. Predictions from a previously developed one-dimensional model, coupling mass- and heat-transfer effects, are compared to experimental polarization curves. The influence of the anode and cathode relative humidification level on the cell performance is explained under the light of the predicted water content across the membrane. Under the operating conditions studied, the net water flux of water is toward the anode. Accordingly, the influence of the anode humidification is not significant, and the influence of the cathode humidification has a high impact in fuel cell performance. Results show that fuel cell performance is better for experiments where higher water content values were obtained. In comparison to the anode feed flow rate influence, the influence of the cathode feed flow rate has a major impact in fuel cell performance.