Antimicrobial activities of silver nanoparticles of extra virgin olive oil and sunflower oil against human pathogenic microbes.

Silver nanoparticles were synthesized using extra virgin olive oil (Olea europaea L.) and sunflower oil (Helianthus annuus L.) and characterized by UV-vis spectroscopy, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The brown color solution of olive oil nanoparticles (EVOO-NPs) and sunflower oil nanoparticles (SFO-NPs) showed typical absorption at 418 nm and 434 nm respectively. The morphology of extra virgin olive oil was found to be in semi cubic shapes with particle size of 23.45 nm (XRD) and 42.30 nm (SEM) while particle size of (SFO-NPs) had 42.30 nm (XRD) and 46.80 nm (SEM). Antimicrobial activities of crude extra virgin olive oil (EVOO), crude sunflower oil (SFO), synthesized nanoparticle from (EVOO-NPs) and (SFO-NPs) against human pathogenic strains were investigated. Synthesized nanoparticle from each oil showed a potent antimicrobial activity against all tested micro-organisms than crude oil which increased by (81.14% to 174.65 %) and by (111.65% to 192.31 %) than (EVOO) and (SFO) respectively. Both (EVOO-NPs) and (EVOO) had more antimicrobial activities than (SFO-NPs) and (SFO). EVOO (NPs) and SFO (NPs) showed maximum antibacterial activities against K. pneumoniae. Therefore (EVOO-NPs) and (SFO-NPs) could be used as safe natural product against multidrug resistant microbes.

The seropervelance of infectious hepatitis viruses (HBV, HCV and HEV) among blood donors and their correlation to risk factors in Qena governorate, Upper Egypt.

This study was performed to determine the prevalence of HBV and HCV infection among blood donors and the occurrence of HEV in hepatitis viruses seropositive blood donors. Also, to investigate the correlation between the occurrence of hepatitis viruses and other risk factors (gender, age, occupation, educational level, residency and donors' types). A total of 11,604 blood samples from apparently healthy blood donors of age range 18-60 years old were collected. The blood donors were categorized as voluntary and replacement donors. Blood samples from donors were tested for the presence of HBsAg, HCV and HEV antibodies by using Enzyme-linked immunosorbent assay. The overall results indicated that 671 out of 11,604 blood donors; 370 persons (3.188%) HCV, 295 persons (2.542%) HBV and 6 persons (0.052%) HCV and HBV; were hepatitis viruses seropositive donors. The prevalence of HEV were 193 (28.76%) among these seropositive blood donors. There is a highly significant correlation among HCV, HBV and other risk factors. Also, the HEV showed high significant with age and educational level and significant with donor types and locations. All investigated virus combinations (HEV/HCV, HEV/HBV and HEV/HCV/HBV) were highly significant with the risk factors except for occupation. In conclusion, the HEV is significantly correlated to HCV and HBV seropositive donors and should be screened among blood donors.

Selective oxidation of trimethylolpropane to 2,2-bis(hydroxymethyl)butyric acid using growing cells of Corynebacterium sp. ATCC 21245.

Multifunctional chemicals including hydroxycarboxylic acids are gaining increasing interest due to their growing applications in the polymer industry. One approach for their production is a biological selective oxidation of polyols, which is difficult to achieve by conventional chemical catalysis. In the present study, trimethylolpropane (TMP), a trihydric alcohol, was subjected to selective oxidation using growing cells of Corynebacterium sp. ATCC 21245 as a biocatalyst and yielding the dihydroxy-monocarboxylic acid, 2,2-bis(hydroxymethyl)butyric acid (BHMB). The study revealed that co-substrates are crucial for this reaction. Among the different evaluated co-substrates, a mixture of glucose, xylose and acetate at a ratio of 5:5:2 was found optimum. The optimal conditions for biotransformation were pH 8, 1v/v/m airflow and 500rpm stirring speed. In batch mode of operation, 70.6% of 5g/l TMP was converted to BHMB in 10 days. For recovery of the product the adsorption pattern of BHMB to the anion exchange resin, Ambersep(®) 900 (OH(-)), was investigated in batch and column experiments giving maximum static and dynamic binding capacities of 135 and 144mg/g resin, respectively. BHMB was separated with 89.7% of recovery yield from the fermentation broth. The approach is applicable for selective oxidation of other highly branched polyols by biotransformation.