Green and Fast Extraction of Chitin from Waste Shrimp Shells: Characterization and Application in the Removal of Congo Red Dye

Due to their detrimental and carcinogenic effects, synthetic organic dyes pose significant environmental and health risks. Consequently, addressing the bioremediation of industrial wastewater containing these organic dyes has become an urgent environmental concern. The adsorption using low-cost and green materials is one of the best alternative techniques for the removal of dyes. This study aims to investigate the use of chitin to eliminate Congo red (CR), an anionic dye, from wastewater. The chitin was produced from shrimp shell in a quick and environmentally friendly manner by utilizing a co-solvent (glycerol/citric acid (GLC)). The resulting adsorbent was characterized through various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and FT-IR spectroscopy. The effectiveness of CR removal with chitin was studied with respect to contact time, adsorbent dose, initial pH, equilibrium isotherms, and kinetic and thermodynamic parameters. It was observed that variations in the dye concentration and pH significantly influenced the removal of CR with chitin. Under optimal operating conditions (pH = 7, contact time = 130 min, temperature = 50 °C), the adsorption capacity reached 29.69 ± 0.2 mg/g. The experimental data revealed that CR adsorption onto a chitin adsorbent is better represented by a Langmuir isotherm

Oxidative stress and cytotoxic potential of anticholinesterase insecticide, malathion in reproductive toxicology of male adolescent mice after acute exposure

Objective(s):The present study was undertaken to determine the effects of acute exposure to malathion on oxidative stress and cytotoxic potential of anticholinesterase insecticide, malathion in reproductive toxicology of adolescent male mice. Materials and Methods: Thirty two adolescent male mice at pubertal age were treated with 500 mg/kg body weight (BW) of malathion for three days. After exposure, biochemical markers and sperm analysis were evaluated and finally histological modifications of testis and sperm were assessed. Results: Our data showed that treatment of male mice with malathion (500 mg/kg, BW) could lead to oxidative stress. Induced oxidative stress status can be assessed due to increased malondialdhyde (MDA) content, decreased thiol group content, as well as increased antioxidant enzyme activities. On the other hand, exposure to malathion at the pubertal age led to alteration of semen parameters; sperm production and percentage of motile sperm were decreased in the treated groups compared to the control.  Furthermore, exposure of male mice to malathion led to a decrease of testosterone level, inhibition of acetylcholinesterase, and decrease of the reproductive performance of male mice after three days of treatment at the age of puberty. Conclusion: The importance to carry out in vitro reproductive toxicology assays lies on the need of knowing the alterations these insecticides may cause at cellular level, since they are endocrine disruptors that interfere with reproductive functions

Stimulated growth rate by restriction of P availability at moderate salinity but insensitive to P availability at high salinity in Crithmum maritimum

The halophyte Crithmum maritimum thrives in cracks of calcareous rocks or cliffs at seashores, a situation which associates limited phosphorus availability and high salinity. In order to understand the common patterns of colonization and zonation of this species, seedlings were cultivated for 34 d in inert sandy soil irrigated with a nutrient solution containing or not phosphorus at moderate (50 mM) or high (250 mM) NaCl level. Net assimilation rate and consequently relative growth rate increased in response to P deprivation at moderate saline level, but not at high salinity level. Parallelly, CO2 fixation rate, rubisco capacity, transpiration rate and stomatal conductance were diminished by P deprivation at moderate NaCl level. Intercellular CO2 concentration was therefore not affected. Chlororophyll fluorescence analysis revealed that photosynthetic systems were insensitive to change in P availability at moderate salinity level: neither pigment content, nor effective and maximum quantum yield, photochemical and non photochemical quenching, and electron transport rate were affected by P deprivation. On the contrary, at high salinity level when net photosynthesis, rubisco capacity and the quantum yields of PS2 were severely affected, P deprivation strongly augmented electron transport rate. Stomatal aperture and more modest increase in net photosynthesis, rubisco capacity, photosystem II effective quantum yield and photochemical quenching accompanied this response. This study shows the tolerance of C. maritimum to the phosphorus deprivation combined to moderate or to high saline level which may explain the common patterns of colonization and zonation of this species

From immunotoxicity to carcinogenicity: the effects of carbamate pesticides on the immune system

International audienceThe immune system can be the target of many chemicals, with potentially severe adverse effects on the host's health. In the literature, carbamate (CM) pesticides have been implicated in the increasing prevalence of diseases associated with alterations of the immune response, such as hypersensitivity reactions, some autoimmune diseases and cancers. CMs may initiate, facilitate, or exacerbate pathological immune processes, resulting in immunotoxicity by induction of mutations in genes coding for immunoregulatory factors and modifying immune tolerance. In the present study, direct immunotoxicity, endocrine disruption and inhibition of esterases activities have been introduced as the main mechanisms of CMs-induced immune dysregulation. Moreover, the evidence on the relationship between CM pesticide exposure, dysregulation of the immune system and predisposition to different types of cancers, allergies, autoimmune and infectious diseases is criticized. In addition, in this review, we will discuss the relationship between immunotoxicity and cancer, and the advances made toward understanding the basis of cancer immune evasion