New morphological criteria and molecular characterization of black aspergilli aggregate from corn, sorghum and wheat grains.

Corn, sorghum and wheat grains are used as livestock feed in the world. Identification of black aspergilli associated with these grains is necessary to make sure of the safety of the grains because its occurrence is an indicator of mycotoxin production. Forty-five isolates were isolated from the samples collected from Upper Egypt's markets and identified morphologically based on colony color, conidia, stipe and vesicle size and molecularly by using ß-tubulin and calmodulin genes. Isolates were divided into 30 strains of Aspergillus welwitschiae and 15 strains of A. niger. We have found new criteria in the morphological identification of A. welwitschiae as its colony color was black to brown with yellow edge, but in A. niger was black with white edge, also A. welwitschiae sometimes produced finely-to-distinctly roughened brownish conidia on malt extract agar (MEA) media. Thirteen isolates of A. welwitschiae and six of A. niger were recognized as potential producers for ochratoxin A.

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.

Diversity of keratinophilic fungi on human hairs and nails at four governorates in upper egypt.

The mycobiota of 160 hair and nail samples collected from 4 different governorates in upper Egypt were estimated using soil plate method for isolating keratinophilic and dermatophytic fungi. Twenty-three fungi were recorded on both hair and nail samples collected from the four governorates. Highest fungal diversity (20) was collected from Red Sea samples followed by Qena (18) and Aswan (17) while lowest fungal diversity was recorded from Sohage samples. The common genera were Aphanoascus, Aspergillus, Penicillium, Paecilomyces and Chrysosporium. The most prevalent species belonging to these genera were: A. fulvescens, Aphanoascus sp. A. flavus link, A. flavus var. columnaris, P. chrysogenium. P. lilacinus and C. sulfureum. True dermatophytes such as Nannizzia fulva appeared in 20~30% of the male samples.