This study investigates the performance of acetate feed membrane less single chamber microbial fuel cell and physical characterization of the bio film present on the anode surface using Scanning Electron Microscope (SEM) and 16S rRNA analyzer. The performance has been investigated using Teflon treated carbon paper with 0.3 mg/cm2 Pt/C loaded as a cathode and carbon paper as an anode. The maximum open circuit potential is noticed as 791 mV, the system successfully revealed a maximum power density of 86.1 mW m−2 at stable current density of 354 mA m−2 with high coulombic efficiency of 65% at maximum degradation rate of 96%. SEM showed the dense adherence of microorganisms on the anode. 16S rRNA sequencing results indicates phylogenetic mixture in the communities of anodic biofilm and there is no single dominant bacterial species. The dominant phyla are Firmicutes, Gamma Proteobacteria, Alpha Proteobacteria, Actinobacteria, with ten dominant microbial strains: Bacillus firmus, Shewanella profunda, Bacillus isronensis, Brevundimonas bullata, Pseudomonas putida, Planococcus citreus, Micrococcus endophyticus, Acinetobacter tandoii, Bacillus safensis and Shewanella xiamenensis.

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To identify the most important ripening parameters of Fuerte avocado fruits, and to quantify the relationship between color changes, electrical conductivity and softening of avocado fruits, the ripening process was investigated to fulfill the consumer and market demands. Mature and high quality avocado fruits (Persea Americana Mill.) were held to ripe at 20 o C in controlled temperature rooms with 90-95% relative humidity for two weeks. Fruit quality characteristics (respiration rate, soluble solids content (SSC), total acidity (TA), ascorbic acid and oil content) during ripening period at 20 o C were evaluated. Moreover, ripening parameters as color changes, chlorophyll contents, fruit firmness and electrical conductivity and ripening enzymes (CX and PME) were also investigated throughout ripening process. During ripening period for 2 weeks at 20 o C, fruit quality criteria showed that respiration rate and oil content had a noticeable significant increase with the ripening increase. While, acidity (TA), soluble solids (SSC) and ascorbic acid content cleared a slight and significant decrease. Throughout color development, the three parameters lightness (L*), hue (h•) and chroma (C*) changed significantly, hue decreased little, lightness moderately, while chroma changed more quickly. Moreover, an significant decline in chlorophyll a and b concentration occurred and reflected to color changes during ripening process. For ripening enzyme activities, Fuerte avocado fruits showed a great increase in cellulase activity compared with gradual decrease in Pectinmethylesterase activity after ripening. Avocado fruit firmness markedly reduced gradually after harvest till ripening at 20 o C, and this decline was positively correlated with an increase of electrical conductivity of the fruit tissue suggesting a gradual loss of cell membrane integrity. This increase in conductivity was promoted by ripening process. These results have allowed us to set that ripening process had some parameters were simple and rapid to measure as ripening indices. We conclude that in Fuerte avocado fruits, electrical conductivity (EC) can serve as a good indicator of membrane permeability and that it is highly correlated with ethylene production, softening and also demonstrates a relationship between firmness and EC.

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Background: Biomass produced as a byproduct from the β-mannanase production process by Aspergillus tamarii NRC 3was evaluated as a biosorbent for the removal and recovery of some heavy metal ions.Results: Under optimal conditions, the isolated strain recorded the highest β-mannanase activity (31.88 Uml −1 ). Thus, the biomass produced from mannanase production process as a byproduct was evaluated as a biosorbent for the removal and recovery of some heavy metal ions from aqueous solutions and an industrial wastewater. The fungal biomass was found to be efficient for the removal of Cu +2 and some heavy metal ions. The biosorption process of copper(II) by Aspergillus tamarii NRC 3 biomass was affected by changing of time, temperature, pH, metal ions concentration, the presence of some heavy metals, and biomass concentration. The rate of Cu +2 uptake from Cu +2 solution proceeded rapidly, and it appeared to be virtually complete during the initial 5 min (92%); the maximum uptake of Cu +2 appeared at 30°C, pH 5, and biomass concentration 5 g w/w. On the other hand, the fungal biomass was to remove considerable proportion of Pb 2+ , Co +2 , Ni 2+ , Fe +3 , and Cr 3+ in addition to Cu 2+ . The uptake of Cu +2 by pretreated biomass was studied. Recovery of the sorbed metal ions by desorbing agents and the potential reuse of the regenerated biomass in metal ions uptake (reloading) were evaluated. Conclusions: Aspergillus tamarii NRC 3 biomass seems to be quite feasible in the removal of heavy metal ions especially Cu +2 from aqueous solutions.

Microbial protease represents the most important industrial enzymes, which have an active role in biotechnological processes. The objective of this study was to isolate new strain ofStreptomycesthat produce proteolytic enzymes with novel properties and the development of the low-cost medium. An alkaline protease producer strain NRC-15 was isolated from Egyptian soil sample. The cultural, morphological, physiological characters and chemotaxonomic evidence strongly indicated that the NRC-15 strain represents a novel species of the genusStreptomyces, hence the nameStrptomyces pseudogrisiolusNRC-15. The culture conditions for higher protease production by NRC-15 were optimized with respect to carbon and nitrogen sources, metal ions, pH and temperature. Maximum protease production was obtained in the medium supplemented with 1% glucose, 1% yeast extract, 6% NaCl and 100 μmol/L of Tween 20, initial pH 9.0 at 50 °C for 96 h. The current results confirm that for this strain, a great ability to produce alkaline proteases, which supports the use of applications in industry.

Two experiments were conducted during the summer and winter seasons of 2013 to study the effect of grafting using different rootstocks on the yield and quality and chemical analysis of cucumber (Cucumis sativus L.) cultivar "Hady" under high and low temperatures. The experiments consisted of 5 treatments, 4 rootstocks, namely Bottle Gourd (Lagenaria siceraria Standl.), Supper Shintosa (Cucurbita maxima Duchesne×Cucurbita moschata Duchesne), Squash 3 (Cucurbita pepo) and Ferro' (C. maxima × C. moschata), in addition to non-grafted control. Data were recorded on plant length and physical characters of fruits 30, 60 and 90 days after planting, early and total yield/m2, chemical characters (percentage of dry matter, TSS and total and reducing sugars) of cucumber fruits and percentage of N, P and K in cucumber leaves. The results indicated that Ferro rootstock increased plant height, physical characters, early and total yield of cucumber fruits in both summer and winter seasons, as compared with non-grafted control. No significant effect was detected from using rootstocks on N, P and K percentage in cucumber leaves, except grafting cucumber on Bottle Gourd rootstock which significantly increased N% only in the winter season. Chemical contents of cucumber fruits were not affected by grafting in summer season, while Bottle Gourd increased total sugars and Ferro rootstock caused significant increase in the percentage of dry matter and reducing sugars in winter season as compared with non grafted plants.