Search

Antibiotics serve as the cornerstone of the treatment of bacterial diseases in the aquaculture sector. In this study, 210 Nile tilapias (Oreochromis niloticus) weighing approximately 60 ± 2.5 g b.w. were randomly divided into seven treatments (T1–7). The fish were experimentally infected with Aeromonas hydrophila and then treated with oxytetracycline (OTC) after the appearance of clinical symptoms. The fish were fed Moringa oleifera diet alone or M. oleifera diet before OTC treatment to alleviate the effects of OTC treatment. The effects of OTC treatment and M. oleifera were assessed by measuring the gene expressions of cytokines (interleukin [IL]‐1β, IL‐6, tumour necrosis factor‐α, IL‐10 and heat shock protein‐70), antioxidant enzymes (catalase, superoxide dismutase, lipid peroxidase and total antioxidant capacity) and liver enzymes (aspartate aminotransaminase, alanine aminotransaminase and alkaline phosphatase). Although OTC treatment protected fish from A. hydrophila, leading to a decreased mortality rate (49.96%), it exerted deleterious effects on their immune and oxidative statuses. Thus, we recommend that M. oleifera be included in the feed of O. niloticus, especially those exposed to bacterial infection. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles (TiO2 NPs) are used in numerous products, such as paints, pharmaceuticals, environmental sanitizing agents and even as a whitening food additive (E171). Residual TiO2 NPs are considered among the emerging contaminants of aquatic environments. However, the effect of such exposure on intestinal microbiota population, microbial disease resistance and the immune-related gene expression of Nile tilapia (Oreochromis niloticus) is largely obscure. Three groups of fish were nurtured on diets containing 1 mg/ml TiO2 NPs with three different sizes (53, 31 and 13 nm), beside the control group for four weeks before sampling fish tissues. Fish groups fed on TiO2NPs diets showed significantly increased higher levels of tumour necrosis factor (TNF-α), interleukin (IL-6) and IL-1β, along with insignificant changes in IL-8 and IL-10 compared with the control group. These changes indicate a strong inflammatory response. Treated fish groups showed a marked decrease in the count of some intestinal microbiota, aeromonas, pseudomonas and lactobacillus. Fish were challenged against A. hydrophila, and a higher mortality rate was observed in the group fed on smaller TiO2 NPs (13 nm). The levels of antioxidant enzymes such as catalase, glutathione peroxidase and superoxide dismutase were significantly increased in groups fed on TiO2 NPs, while metallothionein levels were only slightly changed. In conclusion, feeding fish with diets containing TiO2 NPs (13 and 31 nm) for 4 weeks alters the intestinal microbiota population and provides additional information on the toxic impacts of TiO2 NPs on the health and immune status of O. niloticus. [ABSTRACT FROM AUTHOR]

The hepatoprotective and antioxidant activities of the hydroalcoholic extract (PE) of pea (Pisum sativumL.) by-product were evaluated, using CCl4-induced oxidative stress and hepatic damage in rats. These activities were assessed via measuring alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein and albumin, malondialdehyde (MDA), reduced glutathione (GSH), protein thiols (PSH), nitrite/nitrate levels, glutathione-peroxidase (GSH-Px), glutathione-S-transferase (GST) activities, as well as, histopathological evaluation. PE revealed significant hepatoprotective and antioxidant activities mostly found in n-butanol fraction. Chromatographic fractionation of this active fraction led to the isolation of five flavonoid glycosidesnamely, quercetin-3-O-sophorotrioside (1), quercetin-3-O-rutinoside (2), quercetin-3-O-(6″″-O-Esinapoyl)-sophorotrioside (3), quercetin-3-O-(6″″-O-Eferuloyl)-sophorotrioside (4) and quercetin-3-O-β-D-glucopyranoside (5). The isolated compounds were quantified in PE, using a validated HPLC method and the nutritional composition of pea by-product was also investigated. Our results suggest that pea by-product contained biologically active constituents which can be utilised to obtain high value added products for nutraceutical use. [ABSTRACT FROM PUBLISHER]