Isolation, characterization and control of some clinical candida albicans

There has been an increase in fungal infections especially those caused by Candida during the last two decades. This resulted in the development of different antifungal agents. However, emerging of resistance to these antifungal agents has been encountered

The aim of this study: was to evaluate the effect of some plants extracts and volatile oils on the growth of Candida albicans. In addition to detecting synergistic effect of plant extracts and volatile oils when combined with antifungal agents

Methodology: Identification of Candida albicans using colonial morphology, microscopic examination, germ tube test, chlamydospore formation, sucrose assimilation, methyle blue and fluorescence methods were performed. Susceptibility testing of Candida albicans to antifungal drugs, plants extract and volatile oils was assessed. Detection of synergistic effects of combination on Candida albicans strains was performed. Studying the effect of the stress of tested antifungals and natural products on the ultrastructure of Candida albicans using electron microscopy was detected

Results: Out of 70 Candida spp isolated from different clinical speciemens, 18 [25.7%] were identified as Candida albicans. Natural plant extracts and essential oils have an obvious effect in inhibiting the growth of Candida albicans. The most effective plant extracts were mint, dianthus, Eucalyptus and the most effective volatile oils were thyme, lemon, and peppermint. When fluconazole or nystatin was added for some plant extracts or essential oils it resulted in increasing their effectiveness. Using electronic imaging, there was a clear difference in the ultrastructure of the Candida albicans cell before and after treatment with fluconazole or lemon oil, which proves their influence on the composition of these cells

Incidence of hepatitis A virus among hospitalized children's in Cairo

Hepatitis A virus [HAV] is an important cause of acute hepatitis worldwide that can lead to severe illness or even death. It is transmitted by the fecal-oral route through the consumption of contaminated food or water. This study was carried out to determine the incidence of HAV infection among hospitalized children's with acute hepatitis and genotyping of HAV Strains circulating in Greater Cairo. To fulfill the aim of the work, stool samples were collected from 102 hospitalized Children's, ages ranged from 0.5 to 12 years during the period from Dec. 2007 to Nov. 2008. Collected stool samples were submitted to nested RT-PCR for amplification of the VP1/2A region of the HAV genome. The expected fragment sizes of PCR products were 391bp and 244 bp for the first and second round of PCR, respectively. PCR products, of 2nd round of some positive samples, were purified for nucleotide sequence analysis in both directions. Fragments nucleotide sequences were compared to sequences derived from the corresponding HAV genome regions in the Gen Bank. Obtained data showed that HAV RNA prevalence were 82.35% [84/102] among hospitalized children's with acute hepatitis, and the highest HAV RNA was in the age group 3-5 and 9-12, where it reached 88.88% [40/45] and 81.8% [18/22] respectively, and the lowest prevalence rate was 70% [7/10] in the age group 0.5-2. Also, the incidence of HAV RNAwas higher in females 88.1%[37/42], than in males 78.33% [47/60]. Seasonal variation of HAV revealed that the viral incidence was 100% during winter and spring seasons, [25/25] and [17/17], respectively. While it was 85.36% [35/41] and 36.84% [7/19] in summer and autumn, respectively. Sequence analysis of selected fragments showed that all fragments are the same isolate. The phylogenic tree of positive samples confirmed that the isolated virus sequencing was most closely related to Hepatitis A virus isolate Egypt-swS5 deposited in the Gen Bank by accession no. [FJ0100837.2], with 100% of nucleotide identity

Role of gamma irradiation for self-life extension and improvement the hygienic quality of fresh fish

This work aimed to study the role of gamma irradiation [1.5 and 3 kGy] in improving hygienic quality of fresh Bolti fish [Tilapia nilotica] stored at refrigerator temperature [3C] in prolonging the shelf-life extension and eliminating the pathogenic microorganisms. The results revealed that an irradiation dose of 3.0 kGy was most effective, not only for reducing the total contaminated bacteria, fungi and yeasts but also for a complete elimination of pathogenic Staph. aureus and E. coli; while Strep. faecalis showed some resistance during 30 days of storage without undesirable changes in their organoleptic properties compared with the control samples without any additives. Exposure doses of 1.5 and 3.0 kGy appeared to be most effective in reducing the viable counts of proteinase producing bacteria after 12 days of cold storage by 98.8% and 99.9% respectively, while a complete sterilization occurred at 3.0 kGy

Nutritional requirements for gelatinase biosynthesis by Streptomyces spheroides

effect of some nutritional factors on gelatinase biosyn-thesis by Streptomyces spheroides was studied. The experimental organism was cultivated at static conditions at 30° and pH 7.0 for 8 days. Starch-nitrate medium was used throughout this work. 0.3% gelatin gave the maximum gelatinase activity among the tested organic and inorganic nitrogen sourced, whereas 2.5% glucose and potassium dibasic phosphate [0.15%] were the most suitable carbon and phosphorus sources, respectively; for gelatinase biosynthesis. The effect of different calcium carbonate concentrations was also tested, 0.1% was the best concentration for gelatinase biosynthesis by Streptomyces spheroides

Detection and induction of phenylalanine ammonia - lyase in Streptomyces viridosporus

IN S. viridosporus, L- phenylanine ammonia lyase [PAL] was detected during the exponential growth as well as the stationary phase in the absence of exogenous L-phenylalanine in complex medium. Cultures grown in the defined medium produced little PAL unless supplemented with L-phenylalanine. A higher specific activity of PAL [10-fold higher than in the defined medium without L-phenylalanine] can be obtained during 48 hr of growth in the defined medium containing L-phenylalanine. This amino acid also induces lyase synthesis in a defined medium when used as the sole source of nitrogen, whereas other amino acids completely failed to induce PAL activity. Maximal induction of PAL occurred when L-phenylalanine was used as the nitrogen or carbon source at 0.6% final concentration. On the other hand, ammonia repressed the PAL synthesis in presence of glucose. Moreover, increasing the concentration of glucose up to 2.0% repressed the lyase activity

Isolation of an gelatinase - producing Streptomycete from Egyptian soil and its characterization

An actinomycete which produced appreciable quantities of protease was isolated. The mature aerial mass of the organism is in the yellow colour series when grown on the ISP media. Long chains of unbranched sporophores occur in both the aerial and substrate mycelia. The Spore surface is smooth. LL-Diaminopimelic acid could be detected in the whole cell hydrolysate. These characteristics indicated that it was Streptomyces spheroides. Optimum environmental conditions of gelatinase production wore established in cultures at 30§ after 8 days of incubation at pH 7.5

Influence of sodium bisulfite as an antimicrobial additive compound on growth and nitrogen metabolism of Aspergillus flavus link

The effect of sodium bisulfite on growth and nitrogen metabolism of Aspergilus flavus link was investigated. The concentrations of 0.015, 0.030 and 0.045% were found to inhibit growth of the fungus by 22.1, 51 .3 and 73.4%, respectively. Toal nitrogen was inhibited by 33.1, 43.2 and 75.5% respectively. Protein was also decreased, the percentage of decrease was a factor of sodium bisulfite concentration. Nucleic acids [RNA and DNA] and its related enzymes [nuclease and ribonuclease T1] were inhibited at all experimental sodium bisulfite concentrations, except ribonuclease T1 which showed a significant increase at 0.015%. Total free amino acids were increased at all sodium bisulfite concenrations. The percentage of increases were 285. 7, 359.8 and 94.4% at 0.015,0.03 and 0.045% sodium bisulfite, respectively Methionine appeared at 0.03%, while praline, valine, isoleucine, leucine, tyrosine and phenyl alanine disappeared at 0.045%