Oxidative stress and hepatotoxicity in rats induced by poisonous pufferfish (Lagocephalus lagocephalus) meat

This study was undertaken to evaluate the effect of pufferfish (Lagocephalus lagocephalus) meat poisoning on hepatic functions of Wistar rats. For this purpose, groups of rats (Lcr, Lcu+b and Lcu-b) received diet supplemented with 10% of raw or cooked meat, respectively, with or without cooking water of L. lagocephalus while groups Mcr and Mcu+b received diet supplemented with 10% of raw or cooked meat of Liza aurata, which were used as a negative control. In Lcu+b group, ALT, AST and ALP rates (hepatic enzyme markers) decreased after two months of treatment, indicating liver damage. We also observed an increase of 54 and 65% of thiobarbituric acid reactive substances (TBARS) in their livers respectively 48 hours and two months after treatment compared to controls. The catalase (CAT) activity in group Lcu+b decreased (p < 0.05) after two periods of treatment, whereas metallothionein (MT) level significantly increased and decreased, respectively after 48 hours and two months. In fact, in the histological analysis of the livers from Lcu+b treated group, we observed an increase in vacuolisation, necrosis, hepatocytes ballooning and sinusoids dilation. These results indicate that L. lagocephalus meat cooked with water produces hepatotoxicity and oxidative damage

Extracted tetrodotoxin from puffer fish Lagocephalus lagocephalus induced hepatotoxicity and nephrotoxicity to Wistar rats

This study aimed to investigate the toxicity of raw and boiled tissue extracts of Lagocephalus lagocephalus flesh or liver. Five groups of six male Wistar rats each were used. Four groups received a daily intraperitoneal injection of raw or boiled tissue extracts of L. lagocephalus flesh and liver at a dose of 1 ml/100 g (v/w). The fifth group served as a sham and received a daily intraperitoneal injection of saline solution (1 ml/100 g of 0.9% NaCl, v/w). During the experiment, there was a slight decrease in body weight in all treated groups. Our results revealed that the activities of various enzymes like transaminase, alkaline phosphatase (ALP), gamma glutamyl transpeptidase (γ-GT) and lactate dehydrogenase (LDH) decreased in serum and increased in liver and kidney tissues, producing hepatotoxicity and nephrotoxicity in the treated rats. These observations on the toxicity of this Tunisian puffer fish revealing toxicity especially in the flesh, the edible part of fish, clearly indicate the danger of using this fish as food.Key words: Hepatotoxicity, Lagocephalus lagocephalus, nephrotoxicity

Efficiency of natural clay and titania P25 composites in the decolouring of methylene blue (MB) from aqueous solutions: dual adsorption and photocatalytic processes

In this paper, we use Tunisian clay materials as alternative low-cost adsorbents, as well as substrates to immobilise TiO2 for the decolouration of methylene blue (MB) dye solutions. The collected raw clay from the mine of Tamra was characterised by various techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). XRD patterns of the raw clay showed halloysite as the main phase (61%), with a lower content of kaolinite (39%). For MB adsorption, the experimental data were fitted by Langmuir and Freundlich adsorption equations. It was found that the studied clays alone were not very efficient at adsorbing MB dye molecules. The decolouration of MB was improved by adding a photocatalytic function to the clay, by adding various amounts of TiO2 nanopowder (20–80&nbsp;wt%) to the clay, imbuing it with photocatalytic capabilities. These combined effects of the phenomena of adsorption and photocatalysis for MB removal by the TiO2-doped clay resulted in a very satisfactory performance, even with the relatively low quantity of 20&nbsp;wt% added TiO2 photocatalyst. This gave 48.6% removal after only 30-min adsorption in the dark, increasing to 84.1% removal after a further 3&nbsp;h under UV light, through combined chemo-physical adsorption and photocatalytic decolouration phenomena

Thermomechanical Autovaporization (MFA) as a Deodorization Process of Palm Oil

Throughout the vegetable oil industry, there is a focus on eradicating the volatile molecules affecting the aroma or taste of the crude oil, whether it is natural or derived from the extraction process. Refining aims to reduce these compounds to a level acceptable to the consumer. In addition, the famous conventional operation of deodorization calls for high levels of temperature depending on the boiling point used to remove the atmospheric pressure of each molecule. The process implies a vacuum level between 10 to 80 kPa absolute pressure, a temperature generally between 190 and 240 &deg;C, and a duration of 2 to 3 h. These conditions necessarily (inevitably) lead to a decrease in the quality of refined oil. Recently, the application of the Multi-Flash Autovaporization &ldquo;MFA&rdquo; operation has shown the possibility of eradicating volatile molecules while adopting relatively low temperature and time levels. Despite the high boiling temperature of the volatile organic compounds (VOC), MFA leads to good efficiency in reducing VOCs and preserving oil quality. The main odorant compounds in the crude palm oil were E-2-Hexenal, heptanal, octanal, nonanal, and decanal. Specific literature can indicate precise boiling temperatures under atmospheric pressure. In addition, many experimental studies have explained the evolution of each molecule and shown how they depend on the operating parameters (inlet oil pressure from 200 to 450 kPa and from 5 and 30 s time of each cycle, and the number of cycles up to 7), and how the empirical mathematical models describe the MFA deodorization, estimate the efficiency of the whole process, and optimize the operating parameters. In this research, the thermodynamic data of absolute pressure volatility versus temperature was used to better identify the removal rate (up to around 87%) implied by an abrupt pressure drop to a vacuum of 5 kPa for p = 450 kPa, t = 25 s/cycle, and the number of cycles (C = 6). The safeguarding of the fatty acid profile illustrated the maintenance of the oil quality

Production of silica gel from Tunisian sands and its adsorptive properties

Thanks to its highly absorbent character, silica gel is used in several applications, such as air moisture removal, as a treatment agent for effluents. In this study, silica gels were synthesised from Tunisian sands, collected from the Fortuna and Sidi Aich Formations in northern and central Tunisia. The collected quartz sand raw materials, as well as the prepared silica gels, were characterised by different techniques, such as X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). XRD patterns of quartz sands showed quartz as main phase (86.1–98%), with lower contents of potassic feldspars, along with kaolinite and calcite. These quartz sands presented relatively small quantities of Fe2O3 (0.3%–0.5%) and TiO2 (0.1%–0.6%). The synthesised silica gels exhibited pore diameters exceeding 20&nbsp;Å and surface areas up to 194&nbsp;m2/g, comparable with those described in the literature and commercial silica gel. N2 adsorption isotherms showed that the silica gels prepared from Tunisian sands are mesoporous materials with high adsorption capacities. To understand better their adsorbent properties and applicability on an industrial scale, these gels were tested for methylene blue (MB) absorption. Maximum decolourisation rates (up to 96% after a contact time of 180&nbsp;min) occurred with products synthesised at pH 3. The adsorption mechanism fitted better with a Langmuir model, revealing a monolayer coverage process of MB molecules over the gel surface, and the adsorption kinetics of the dye on these materials is well described by the second order model. The corresponding equilibrium adsorption capacities obtained from experimental data (Qexp&nbsp;=&nbsp;292–214&nbsp;mg/g) were close to the estimated maximum adsorption capacities (Qe&nbsp;=&nbsp;333–250&nbsp;mg/g), and to that of an industrial silica gel (250&nbsp;mg/g)