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Roig B.,University of Nimes | Mnif W.,University of Monastir | Mnif W.,Institute Superieur Of Biotechnologie Of Sidi Thabet | Hadj Hassine A.I.,University of Monastir | And 5 more authors.
Critical Reviews in Environmental Science and Technology | Year: 2013

Concerns over the threats posed by a large number of molecules, collectively termed as endocrine disrupting compounds (EDCs) and generally known to alter and disrupt hormone systems and physiological functions, have often been expressed in academic and scholarly debates. From the perspective of classical toxicology, EDCs have genomic mechanisms of actions and exert agonistic or antagonistic effects on steroid receptors. They are also able to alter reproductive function by binding to estrogen or androgen receptors, and the neuroendocrine system by binding to the thyroid receptor. Recently, EDCs have been shown to have equally complex nongenomic mechanisms, altering steroid synthesis or steroid metabolism. As environmental contaminants, these molecules proved disruptively harmful for many wildlife species, particularly those from or depending on the aquatic ecosystem. An increasingly growing body of research has voiced further concerns that human populations are not immune from the dangers of EDCs. Studies from this line of research caution that EDCs can alter hormonal balance and that a whole range of breast and prostate cancers, endometriosis, cryptorchidism, and hypospadias have been linked to exposure to EDCs. This particular area has raised a lot of controversy and the literature on this subject often presents opposing, and sometimes conflicting, perceptions and perspectives. Accordingly, the authors aimed to contribute to the committed academic search for better appreciation of the topic. They first discuss the major natural and synthetic chemicals with endocrine disrupting properties to which humans and wildlife may be exposed. They then describe the key endocrine mechanisms of action and conclude by addressing the main observed effects in human and wildlife populations. © 2013 Copyright Taylor and Francis Group, LLC.

Mnif W.,University of Monastir | Mnif W.,Institute Superieur Of Biotechnologie Of Sidi Thabet | Hassine A.I.H.,University of Monastir | Bouaziz A.,University of Monastir | And 3 more authors.
International Journal of Environmental Research and Public Health | Year: 2011

Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health. © 2011 by the authors; licensee MDPI, Basel, Switzerland.

Yaich H.,University of Sfax | Garna H.,Institute Superieur Of Biotechnologie Of Sidi Thabet | Besbes S.,University of Sfax | Barthelemy J.-P.,University of Liege | And 3 more authors.
Food Hydrocolloids | Year: 2014

The impact of the extraction conditions has been studied on the yield, chemical composition, rheological and textural properties of ulvan from the green seaweed Ulva lactuca. High ulvan yield was obtained after combining enzymatic and chemical extraction but the lowest yield results at the drastic conditions (pH 1.5 and 90°C). Besides, solvent acidity was an important parameter controlling the ulvan extraction efficiency. The different extraction processes affected chemical composition of ulvan extracts and in particular, sulphate, ash and sugar contents. Low proportions of galactose, glucose and protein were also found in sulphated polysaccharides. The extract, which is resulted from combined enzymatic and chemical extraction, was mainly composed of high peak molecular weight polysaccharides. Ulvan hydrocolloids demonstrated a pseudoplastic behavior. Viscoelastic behavior was carried out at a concentration of 1.6% (w/v) in the presence of 7mM sodium tetraborate and at pH 7.5. However, polysaccharides formed a gel. It was not the case for the extract at pH 1.5 and 90°C under the same conditions. The results showed that a significant effect of the conditions of extraction on the textural characteristic (firmness, springiness and adhesiveness) of ulvan gels. © 2014 Elsevier Ltd.

Tir M.,Tunis el Manar University | Rebeh I.,Tunis el Manar University | Telahigue K.,Tunis el Manar University | Hajji T.,Institute Superieur Of Biotechnologie Of Sidi Thabet | And 2 more authors.
JAOCS, Journal of the American Oil Chemists' Society | Year: 2015

The goal of this study was to evaluate the chemical composition and the fatty acid profile of mantle and tentacle of male and female Sepia officinalis, sampled at four seasons from the Mediterranean sea of Tunisia. S. officinalis were found to be rich in glycogen, protein and oil, and significant differences were observed between samples. The level of saturated fatty acid and unsaturated fatty acid showed significant variability among sex and during seasons. DHA and EPA, as polyunsaturated fatty acids, were the most abundant in all samples (14.8-27.8 % and 10.4-18.3 %, respectively). Oleic acid was the most abundant monounsaturated fatty acids (1.63-4.52 %). ∑n3 and ∑n6 was remarkably different between seasons and among sex. This study could be suitable for the development of reliable guide of fatty acid accumulation in cephalopod. © 2015 AOCS.

Garna H.,Institute Superieur Of Biotechnologie Of Sidi Thabet | Emaga T.H.,University of Liege | Emaga T.H.,African Research Center on Bananas and Plantains | Robert C.,University of Liege | Paquot M.,University of Liege
Food Hydrocolloids | Year: 2011

A new technique for the purification of pectins using protein (sodium caseinate) was developed and that could replace the process of ethanol which is currently used in industries. Commercial pectins were used as a model to verify the feasibility of the process and to define some important parameters. The results indicated that this purification technique is based primarily on the electrostatic interactions between these two polymers. The electrostatic interactions were strongly dependent on pH and salt concentration. The maximum pectin precipitation was obtained at pH 3.5. At this pH, the pectin acquires a negative charge while the protein is positively charged, promoting thus their attractions. Furthermore, the dissociation of the pectin-caseinates complex and the precipitation of caseinate at pH 4.6 were observed in the presence of salt. This method is very specific, suggesting that it could be used to purify some electrically charged polysaccharides. © 2010 Elsevier Ltd.

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