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Forty samples of beef burger and sausage (20 for each) were collected from supermarkets in Assiut Governorate during the period from July to November 2011. Samples were mycologically analyzed using dichloran Rose Bengal Chloramphenicol (DRBC) and dichloran 18% glycerol (DG18) agar media. The total number of fungal species on DRBC was higher than that on DG18 (46 versus 31 species in case of beef burger and 41 versus 33 in sausage). In the individual samples the fungal load varied from 6 - 600 colonies/g whereas the number of fungal species fluctuated between 2 and 8 species. Aspergillus, Penicillium and yeasts were the most prevalent fungi contaminating 70-100 % of the samples. Aspergillus niger, A. terreus, A. flavus, Penicillium chrysogenum and P. citrinum were the most common mould species on both beef burger and sausage samples. Sequencing of rRNA gene revealed the identification of 12 species belonging to 6 genera of yeasts which comprised Candida parapsilosis, Galactomyces candidum, Pichia kudriavzevii and Trichosporon domesticum as common ones. Testing the natural occurrence of mycotoxins showed that diacetoxyscirpenol and zearalenone contaminated 25 and 5 % of beef burger samples respectively whereas aflatoxin B1 was found in only 10 % of sausage samples. Out of 24 fungal species isolated from both substrates 10 (40 %) were able to produce detectable quantities of mycotoxins. Aflatoxin B1 was detected in the extracts of A. flavus cultures while aflatoxin B1, B2, G1 and G2 were produced by three isolates of A. parasiticus. Sterigmatocystin was formed by one isolate of Emericella nidulans whereas fumonisin B1 was secreted by two isolates of F. verticillioides. Most fungal isolates were able to produce lipolytic and proteolytic enzymes with the most active belong to A. parasiticus and F. oxysporum, which were also toxinogenic.

This study was aimed to investigate the feasibility of bio- ethanol production by batch fermentation of kareish cheese whey. Two forms of whey; untreated (crude) whey containing 5% lactose and treated whey (deproteinized and concentrated to 14% lactose) were utilized. Fermentation processes were performed by two strains of Kluyveromyces marxianus and four strains of Saccharomyces cerevisiae which were previously recognized as ethanol- producing strains. Effects of different initial pH values, as well as, external supplementation of treated whey by four different nitrogen sources on the rate of ethanol production by two of the highest producing strains were also investigated. All the studied yeast strains were able to grow and produce ethanol from both crude and treated whey. Levels of ethanol production ranged between 3.4- 18.5g/l and 24.11-57.66 g/l from crude and treated whey, respectively. The most suitable initial pH maximizing ethanol yield was 5.5 and the best added nitrogen source was yeast extract. Maximum ethanol levels produced by K. marxianus ZMS3GU133329 and S.cerevisiae EC1118 from treated whey adjusted to pH 5.5 and supplemented by 0.3% yeast extract reached to 69.85 and 65.36 g/L, corresponding to 97.8 and 91.4% of the theoretical values, respectively. The kinetic parameters and productivity were calculated and discussed for all experiments.

This study was aimed to investigate the feasibility of bio- ethanol production by batch fermentation of kareish cheese whey. Two forms of whey; untreated (crude) whey containing 5% lactose and treated whey (deproteinized and concentrated to 14% lactose) were utilized. Fermentation processes were performed by two strains of Kluyveromyces marxianus and four strains of Saccharomyces cerevisiae which were previously recognized as ethanol- producing strains. Effects of different initial pH values, as well as, external supplementation of treated whey by four different nitrogen sources on the rate of ethanol production by two of the highest producing strains were also investigated. All the studied yeast strains were able to grow and produce ethanol from both crude and treated whey. Levels of ethanol production ranged between 3.4- 18.5g/l and 24.11-57.66 g/l from crude and treated whey, respectively. The most suitable initial pH maximizing ethanol yield was 5.5 and the best added nitrogen source was yeast extract. Maximum ethanol levels produced by K. marxianus ZMS3GU133329 and S.cerevisiae EC1118 from treated whey adjusted to pH 5.5 and supplemented by 0.3% yeast extract reached to 69.85 and 65.36 g/L, corresponding to 97.8 and 91.4% of the theoretical values, respectively. The kinetic parameters and productivity were calculated and discussed for all experiments.

Six high ethanol producer yeast strains (two strains of Kluyveromyces marixianus and four of Saccharomyces cerevisiae) were utilized to produce ethanol from treated and non-treated Egyptian sugar cane molasses with gravity (10, 15, 20, 30 & 33.3% sugar). The treated molasses was obtained by heating diluted molasses up to 90ºC and adjusting its pH to 4.5. All yeast strains used produced higher ethanol yield from non-treated molasses with 10% sugar than that obtained from the treated one with the same sugar concentration. On the other hand, treated molasses yielded better ethanol concentration than that gained from non-treated molasses with 15 – 25% sugar. Maximum ethanol production (125.89% g/l) was noticed with fermentation efficiency of 99.97% using S. cerevisiae EC1118 strain on 25% sugar treated molasses at 35ºC. The same strain gave low levels of ethanol when the sugar concentration of the treated molasses was either 30 or 33.3% at both fermentation temperatures used (35º and 40ºC). The kinetic parameters and productivity were calculated and discussed for all treatments.

Six high ethanol producer yeast strains (two strains of Kluyveromyces marixianus and four of Saccharomyces cerevisiae) were utilized to produce ethanol from treated and non-treated Egyptian sugar cane molasses with gravity (10, 15, 20, 30 & 33.3% sugar). The treated molasses was obtained by heating diluted molasses up to 90ºC and adjusting its pH to 4.5. All yeast strains used produced higher ethanol yield from non-treated molasses with 10% sugar than that obtained from the treated one with the same sugar concentration. On the other hand, treated molasses yielded better ethanol concentration than that gained from non-treated molasses with 15 – 25% sugar. Maximum ethanol production (125.89% g/l) was noticed with fermentation efficiency of 99.97% using S. cerevisiae EC1118 strain on 25% sugar treated molasses at 35ºC. The same strain gave low levels of ethanol when the sugar concentration of the treated molasses was either 30 or 33.3% at both fermentation temperatures used (35º and 40ºC). The kinetic parameters and productivity were calculated and discussed for all treatments.

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This survey was designed to study the diversity and occurrence of rhizosphere and rhizoplane fungi in the protectorate of Assiut in Egypt, followed by testing the ability of the most common isolated fungal strains to produce mycotoxins. Not many mycological studies have been carried out to describe the fungal fl ora of this area, which will be of great signifi cance for the endemic mycobiota. Rhizosphere and rhizoplane samples were collected from the protectorate of Assiut, which represents one of the largest distinctive regions of newly reclaimed soil at the Assiut Governorate. The identifi cation of the isolated fungi during our investigation was carried out using the morphological and microscopic features according to many references and confi rmed by the Assiut University Mycology Center ( AUMC). The most common four fungal species were examined for their capability to produce mycotoxins; in addition, chemical confi rmatory tests for mycotoxins were examined.

This survey was designed to study the diversity and occurrence of rhizosphere and rhizoplane fungi in the protectorate of Assiut in Egypt, followed by testing the ability of the most common isolated fungal strains to produce mycotoxins. Not many mycological studies have been carried out to describe the fungal fl ora of this area, which will be of great signifi cance for the endemic mycobiota. Rhizosphere and rhizoplane samples were collected from the protectorate of Assiut, which represents one of the largest distinctive regions of newly reclaimed soil at the Assiut Governorate. The identifi cation of the isolated fungi during our investigation was carried out using the morphological and microscopic features according to many references and confi rmed by the Assiut University Mycology Center ( AUMC). The most common four fungal species were examined for their capability to produce mycotoxins; in addition, chemical confi rmatory tests for mycotoxins were examined.