No abstract

Stachybotrys microspora is a filamentous fungus characterized by the secretion of multiple hydrolytic activities (cellulolytic and non-cellulolytic enzymes). The production of these biocatalysts was studied under submerged culture using glucose, cellulose, and wheat bran as carbon sources. Endoglucanases, pectinases, xylanases, β-glucanases, chitinases, and proteases were induced on cellulose-based medium and repressed on glucose in both strains with higher amounts produced by the mutant. β-glucosidases were roughly equally produced by both strains under glucose and cellulose conditions. The yield of chitinases, β-glucanases, and proteases produced by Stachybotrys strains was as much higher than the commercialized lysing enzyme called "zymolyase," currently used in yeast DNA extraction. In this context, we showed that S. microspora hydrolases can be successfully applied in the extraction of yeast DNA.

The aim of this work is to study the variation of the global chemical composition of six fish species (Lithognathus mormyrus, Mullus barbatus, Mullus surmuletus, Pagellus erythrinus, Pagrus caeruleostictus and Dentex maroccanus) caught by the trawl of the Gulf of Gabès (Mediterranean Sea). The variations of the chemical contents of the fish as a function of size, sex, organs and parts of the muscle were examined between December 2005 and May 2006. ANOVA indicated that the global chemical composition was significantly affected by two factors: species and body locations (parts of the muscle). The correlation matrix established between the chemical contents showed two highly significant correlations (fat–moisture and protein–ash). The discriminant analysis allowed the distribution in the space of fish species into five groups according to their moisture, proteins, fat and ash contents. The analysis of the fat content in the parts of the fish body revealed the presence of a concentration gradient.

This study was performed to investigate the effect of different cooking methods (frying, steaming and oven cooking) on proximate composition, mineral contents and fatty acid profiles of common pandora (Pagellus erythrinus) fillets. This investigation allows the determination of optimal preparation method to achieve optimal nutritional and healthy fish qualities. The changes in protein and fat contents after oven cooking were found to be insignificant (P > 0.05). The nutritional values of the fish fillets were preserved after steaming and oven cooking. The fatty acid profiles of fish fillets showed differences between cooking methods. The proportion of palmitic acid increased about 40.2 and 39.9% after steaming and oven cooking, respectively, and decreased of 39.1% after frying. The mineral contents of fish fillets (Ca, Na, K, Mg and Fe) prepared by different cooking methods varied significantly (P < 0.05). The ω‐6/ω‐3 ratio, increased due to the frying process. The steaming and oven cooking are preferable cooking methods according to nutritional (protein and fat contents) and healthy (ω‐6/ω‐3 ratio) attributes. Practical Applications In coastal countries, fish is an essential compound of the people diet. Thus, being the impact of different cooking methods on fish's chemical composition is so substantial. For this reason, the study of chemical composition of both fresh and processed fish fillets is so needed for consumers, nutritionists and professional as it allows the former to opt for the best cooking methods of fish fillets.