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.

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Alginate was recovered from Sargassum latifolium biomass using different conditions of alkali treatment.Box-Behnken experimental design was evaluated to study the influence of alkali:alga ratio, temperatureand time on alginate yield, and its molecular weight (MW) and mannuronic/guluronic acid ratio (M/G).The second-order polynomial equations were analyzed by appropriate statistical methods. Extractiontemperature and time were the most important factors during alginate alkaline extraction. MW andM/G ratio played an important role in controlling the reducing power of alginate. Increasing pH of thealginate solutions enhanced its reducing capacity, while thermal treatment showed a negative effect.Additionally, alginate exhibited good emulsion stabilizing capacities with diverse hydrophobic com-pounds. Emulsifying activity was less sensitive to temperature, ionic strength and more stable at acidicpH.

There is a growing demand for chitosan production from fungi as it provides superior physico-chemical properties over traditional crustacean sources. Chitosan was recovered from Aspergillus niger biomass using different conditions of alkali deproteinization and Box-Benhken experimental design was evaluated to study the influence of alkali concentration, temperature and time on chitosan yield, degree of deacetylation (DD) and molecular weight (MW). Chitosan with different physico-chemical properties was obtained under different combinations of extraction factors. Desirability function was then used to predict the best overall combinations of responses. The most desirable compromise allowed for the recovery of chitosan with a yield of 7.0% (w/w), DD 83.64% and MW 2.70 × 104 Da, which were in good agreement with the predicted values. The recovered chitosan exhibited a good hydroxyl radical scavenging activity and ferrous ions chelating ability reached to 82.40% and 87.23%, respectively. Additionally, it demonstrated good emulsion stabilizing capacities with different vegetable oils. The results suggest that fungal mycelia can be used as a promising source of chitosan with important physico-chemical properties suitable for several applications such as food, pharmaceutical, and cosmetic industries.

The beta-amyloid (Aβ) peptide was used as an important biomarker for Alzheimer's disease (AD) diagnosis. The development of an accurate, selective, rapid, and highly sensitive technique for detecting of Aβ level is an important issue in biology, and medicine to assess human health risks. Here, gold nanoparticles (Au NPs) with different size were electrochemically deposited onto the indium tin oxide (ITO) substrate in the presence of different molecular weights of surfactants. The modified substrates were used as a high sensitive electrochemical sensor of in-vitro as well as ex-vivo monitoring of Aβ based on cyclic voltammetry and square wave voltammetry techniques. Our findings revealed that the modification of ITO electrode with Au NPs could enhance its sensor performance with high sensitivity for low concentration levels of Aβ over a wide linear range with a detection limit of about 20.7 ng/g, which is less than the concentration of insoluble Aβ40 (105.4±40.2 μg/g) in brain of AD induced. In addition, Au NPs/ITO modified electrodes have demonstrated ability to monitor Aβ in the brain extracted samples without any potential interference with other components. Raman spectroscopy has been used to confirm the presence of Aβ in the AD-induced samples. Thus, it is applicable for analyzing ex-vivo samples.

The incidence of onion purple blotch disease was investigated at Assiut Governorate, Egypt during 2011. Lesions with typical symptoms of the disease were colonized by Alternaria porri, Stemphylium vesicarium or mixtures of the both pathogens comprising 2.6, 39.8 and 57.6 % of samples, respectively. Four isolates were selected for virulence evaluation according to the nature of isolation, whereas two isolates were individually associated with the diseased samples and two isolates were collectively recovered. Individually, A. porri AUMC9301 and AUMC10453 showed high virulence contributing 81.25 and 78.13 %, respectively. Also, S. vesicarium AUMC10512 and AUMC10519 exhibit severity comprising 37.50 and 25.00 %, respectively. On the other hand, mixture of A. porri AUMC10453 and S. vesicarium AUMC10519 exhibited highest virulence (91.50 %). In conclusion, this investigation proved that onion plants showing purple blotch symptoms mainly colonized by both A. porri and S. vesicarium. Consequently, increase in the disease may be attributed to the association between these pathogens.