Mahmoud Abdel-Hamid

Protective effect of whey proteins against nonalcoholic fatty liver in rats.

BackgroundNonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and can vary from hepatic steatosis to end-stage liver disease. It is the most common liver disease and its prevalence is increasing worldwide. In the present study, the effect of whey proteins on some parameters of NAFLD was investigated.ResultsOral administration of the studied whey proteins products reduced the final body weight of rats. There was a significant reduction effect (P < 0.05) of the tested proteins on hepatic triglycerides, liver enzymes (ALT and AST), lipid peroxidation (malondialdehyde level) and serum glucose. Feeding on whey proteins caused an increase in the reduced glutathione. Hepatic content of reduced glutathione was not affected by any of the used whey proteins, but it showed an increasing tendency (P > 0.05). Liver histology showed an improvement of fatty infiltration in hepatocytes from whey protein groups and gives the histology of liver a normal appearance.ConclusionsThe obtained results indicate a possible role for oral administration of whey proteins in the regulation of liver biochemistries in a rats model of NAFLD. This regulatory effect of whey proteins was accompanied by an improvement in fatty infiltration in hepatocytes and a reduction of oxidative stress parameters.

Antioxidant and antibacterial activities of bioactive peptides in buffalo’s yoghurt fermented with different starter cultures

Abstract The effect of Lactobacillus acidophilus 20552 ATCC (T2) or Lactobacillus helveticus CH 5 (T3) in combination with yoghurt starter (1:1) on the antioxidant and antibacterial activities of the bioactive peptides present in buffalo’s yoghurt was studied. The SDS-PAGE results indicate that all caseins were completely hydrolyzed by both strains, whereas whey protein fractions were still present. All starter cultures have the ability to produce low-molecular-weight bioactive peptides, most of which were originated from β-casein and fewer from αs1 casein. The antioxidant activity (%) of the water-soluble peptide extract from yoghurt samples increased in all samples during storage. Samples containing Lb. helveticus CH 5 showed the highest values. All yoghurt treatments displayed antibacterial activity against Escherichia coli. Control yoghurt and T3 showed higher antibacterial activity on E. coli, Staphylococcus aureus, and Bacillus cereus as compared to T2.

Spectrochemical Analytical Follow up of Phytoremediation of Oil-Contaminated Soil

ABSTRACT Total Petroleum Hydrocarbons (TPH) are one of the most common groups of persistent environmental toxic organic contaminants to many organisms as well as to humans. In the present work, oil-polluted soil samples were phyto-remediated and analyzed. The investigated soil samples were collected from a location close to the oil petroleum production site in Ras-Gharib, Red Sea, Egypt. The phytoremediation process through TPH reduction and/or removal was carried out using Helianthus annuus (sunflower plant) based on its efficiency as a phytoremediator for organic pollutants. A preliminary four-week scheme of Helianthus annuus remediation, supported by twice quantized fertilization, provided a result of ∼56% clean soil. Contaminated and phyto-remediated samples were diagnosed and analyzed through particle size distribution, Carbon-Hydrogen-Sulfur-Nitrogen elemental analysis (CHSN), Organic Matter content (OM%), Total Petroleum Hydrocarbons determination (%) and spectroscopically through Laser Induced Breakdown Spectroscopy (LIBS) and Laser Induced Fluorescence (LIF). Promising results have been achieved indicating the feasibility of planting sunflower for effective TPH remediation of the polluted soil and also the possibility of in situ monitoring of the remediation with easy, cost effective and fast spectrochemical analytical techniques, namely LIBS and LIF.

Determination of Aflatoxins in Plant-based Milk and Dairy Products by Dispersive Liquid–Liquid Microextraction and High-performance Liquid Chromatography with Fluorescence Detection

Abstract The consumption of plant-based milk has increased due to their nutritional attributes. However, these products may contain aflatoxins if contaminated raw materials were used, although little concern is present in international regulation regarding this topic. In this work, dispersive liquid–liquid microextraction (DLLME) was used for the determination of the most important aflatoxins (B1, B2, G1, and G2) in oat, rice, coconut, almond, and birdseed plant-based milk and milk-based products enriched with oats, almonds, and walnuts using high-performance liquid chromatography (HPLC) with photochemical derivatization and fluorescence detection. Calibrations in matrix were performed for all of the samples, obtaining satisfactory linearity, with correlation coefficients exceeding 0.994 for all of the aflatoxins. The precision in terms of repeatability and intermediate precision, expressed as the relative standard deviation, was lower than 9.7%, and recoveries ranged between 82 and 104%, fulfilling current legislation for the determination of aflatoxins. In addition, the limits of quantification were 0.5 µg L−1 for the aflatoxins, allowing the determination of these compounds below the maximum levels established by European Commission in these commodities. Finally, 23 commercial products were analyzed to characterize the presence of these toxins.