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Choi J.-A.,Yonsei University | Hwang J.-H.,Yonsei University | Dempsey B.A.,Pennsylvania State University | Abou-Shanab R.A.I.,Yonsei University | And 8 more authors.
Energy and Environmental Science | Year: 2011

The influence of ultrasonication pretreatment on fermentative bioenergy [ethanol/hydrogen (H 2)] production from a newly isolated microalgae biomass (Scenedesmus obliquus YSW15) was investigated. S. obliquus YSW15 biomass was sonicated for 0 min (control), 5 min (short-term treatment), 15 and 60 min (long-term treatment), which caused different states of cell lysis for microbial fermentation. Long-term sonication significantly damaged the microalgal cell integrity, which subsequently enhanced the bioenergy production. The accumulative bioenergy (ethanol/hydrogen) production after long-term sonication was almost 7 times higher than that after short-term treatment or the control. The optimal ratio of microalgal biomass to anaerobic inoculum for higher bioenergy production was 1:1. Microscopic analyses with an energy-filtering transmission electron microscope (EF-TEM) and an atomic force microscope (AFM) collectively indicated that cells were significantly damaged during sonication and that the carbohydrates diffused out of the microalgae interiors and accumulated on the microalgae surfaces and/or within the periplasm, which led to enhanced bioaccessibility and bioavailability of the biomass. These results demonstrate that ultrasonication is an effective pretreatment method for enhancing the fermentative bioenergy production from microalgal biomass. © 2011 The Royal Society of Chemistry.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: KBBE.2010.3.5-03 | Award Amount: 3.91M | Year: 2011

The project ULIXES aims to unravel, categorize, catalogue, exploit and manage the microbial diversity available in the Mediterranean Sea for addressing bioremediation of polluted marine sites. The idea behind ULIXES is that the multitude of diverse environmental niches of the Mediterranean Sea contains a huge range of microorganisms and their components (e.g. catabolic enzymes) or products (e.g. biosurfactant) that can be exploited in pollutant- and site-tailored bioremediation approaches. ULIXES intends to provide the proof of concept that it is possible to establish and exploit for bioremediation site-specific collections of microbial strains, mixed microbial cultures, enzymes, biosurfactants and other microbial products. These biotechnological resources will be mined by using approaches based on isolation of culturable microorganisms as well as by extensively applying advanced novel meta-omics technologies recently developed by the project partners and exclusively available for ULIXES. Three pollutant classes recognized worldwide as environmental priorities will be considered: petroleum hydrocarbons, chlorinated compounds and heavy metals. A large set of polluted environmental matrices from sites located all over the Mediterranean Sea will be explored, including seashore sands, lagoon sediments, deep sea sediments polluted by heavy oil hydrocarbons at oil tanker shipwreck sites, hypersaline waters and sediments from polluted salty coastal lakes and natural deep hypersaline anoxic submarine basins and mud volcanoes where hydrocarbon seepages occur. The mined collections of microbial biotechnological products will be exploited for development of novel improved bioremediation processes whose effectiveness will be proved by ex situ and in situ field bioremediation trials. A careful dissemination action will be pursued to assure capillary information of the ULIXES results and products to stakeholders and SMEs operating in the sector of marine bioremediation.


Abou-Shanab R.A.I.,Yonsei University | Abou-Shanab R.A.I.,Mubarak City for Scientific Research and Technology Applications | Hwang J.-H.,Yonsei University | Cho Y.,Kwangwoon University | And 2 more authors.
Applied Energy | Year: 2011

Due to increasing oil prices and climate change concerns, biodiesel has gained attention as an alternative energy source. Biodiesel derived from microalgae is a potentially renewable and carbon-neutral alternative to petroleum fuels. One of the most important decisions in obtaining oil from microalgae is the choice of algal species to use. Eight microalgae from a total of 33 isolated cultures were selected based on their morphology and ease of cultivation. Five cultures were isolated from river and identified as strains of Scenedesmus obliquus YSR01, Nitzschia cf. pusilla YSR02, Chlorella ellipsoidea YSR03, S. obliquus YSR04, and S. obliquus YSR05, and three were isolated from wastewater and identified as S. obliquus YSW06, Micractinium pusillum YSW07, and Ourococcus multisporus YSW08, based on LSU rDNA (D1-D2) and ITS sequence analyses. S. obliquus YSR01 reached a growth rate of 1.68±0.28 day-1 at 680nm and a biomass concentration of 1.57±0.67g dwt L-1, with a high lipid content of 58±1.5%. Under similar environmental conditions, M. pusillum reached a growth rate of 2.3±0.55 day-1 and a biomass concentration of 2.28±0.16g dwt L-1, with a relatively low lipid content of 24±0.5% w/w. The fatty acid compositions of the studied species were mainly myristic, palmitic, palmitoleic, oleic, linoleic, g-linolenic, and linolenic acids. Our results suggest that S. obliquus YSR01 can be a possible candidate species for producing oils for biodiesel, based on its high lipid and oleic acid contents. © 2011 Elsevier Ltd.


Abou-Shanab R.A.I.,Yonsei University | Abou-Shanab R.A.I.,Mubarak City for Scientific Research and Technology Applications | Matter I.A.,Yonsei University | Kim S.-N.,Korea Institute of Science and Technology | And 3 more authors.
Biomass and Bioenergy | Year: 2011

Microalgal lipids are the oils of the future for sustainable biodiesel production. One of the most important decisions in obtaining oil from microalgae is the choice of species. A total of 45 algal cultures were isolated from a freshwater lake at Wonju, South Korea. Five microalgal isolates were selected based on their morphology and ease of cultivation under our test conditions. These cultures were identified as strains of Scenedesmus obliquus YSL02, Chlamydomonas pitschmannii YSL03, Chlorella vulgaris YSL04, S. obliquus YSL05, and Chlamydomonas mexicana YSL07 based on microscopic examination and LSU rDNA (D1-D2) sequence analysis. S. obliquus YSL02 reached a higher biomass concentration (1.84 ± 0.30 g L-1) with a lower lipid content (29% w/w), than did Chla. pitschmannii YSL03 (maximum biomass concentration of 1.04 ± 0.09 with a 51% lipid content). Our results suggest that Chla. pitschmannii YSL03 is appropriate for producing biodiesel based on its high lipid content and oleic acid proportion. © 2011 Elsevier Ltd.


Daba A.S.,Mubarak City for Scientific Research and Technology Applications | Youssef G.A.,Alexandria University | Kabeil S.S.,Mubarak City for Scientific Research and Technology Applications | Hafez E.E.,Mubarak City for Scientific Research and Technology Applications
African Journal of Microbiology Research | Year: 2011

Successful utilization of Pleurotus ostreatus (Jacq.) P. Kumm. (type NRRL-0366) mushroom as a type of edible locally isolated mushroom in Egypt at the Mushroom Research Center (Mubarak City for Scientific Research and Technology Applications), to produce extensive hydrolyzing cellulase complex enzymes. This hydrolysis was approached in submerged culture supplemented with avicel PH101 as a substrate for endo-,exoglucanase production. The avicel concentration 6% yielded the maximum enzyme activities (2.46, 1.80 U/ml) for both endo-and exoglucanase activities on basal medium at 27°C, initial pH value of 5.5 for 12 days on rotary shaker (180 rpm) incubation period. Cellulase enzyme was amplified using specific PCR and the amplicone was cloned using TOPO TA cloning vector. The cellulolytic activity of the recombinant protein was examined and high activity was obtained compared with the standard ones. The avicel was used as a sole carbon source in the fermentation medium and the results revealed that, avicel induced the cellulolytic activity of the examined organism compared with those grown on medium deficient of avicel. © 2011 Academic Journals.


Ibrahim S.S.,Cairo University | Hafez E.E.,Mubarak City for Scientific Research and Technology Applications | Hashishe M.M.,Alexandria University
Journal of Experimental and Clinical Cancer Research | Year: 2010

Background. Breast cancer is one of the most common diseases affecting women. Inherited susceptibility genes, BRCA1 and BRCA2, are considered in breast, ovarian and other common cancers etiology. BRCA1 and BRCA2 genes have been identified that confer a high degree of breast cancer risk. Objective. Our study was performed to identify germline mutations in some exons of BRCA1 and BRCA2 genes for the early detection of presymptomatic breast cancer in females. Methods. This study was applied on Egyptian healthy females who first degree relatives to those, with or without a family history, infected with breast cancer. Sixty breast cancer patients, derived from 60 families, were selected for molecular genetic testing of BRCA1 and BRCA2 genes. The study also included 120 healthy first degree female relatives of the patients, either sisters and/or daughters, for early detection of presymptomatic breast cancer mutation carriers. Genomic DNA was extracted from peripheral blood lymphocytes of all the studied subjects. Universal primers were used to amplify four regions of the BRCA1 gene (exons 2,8,13 and 22) and one region (exon 9) of BRCA2 gene using specific PCR. The polymerase chain reaction was carried out. Single strand conformation polymorphism assay and heteroduplex analysis were used to screen for mutations in the studied exons. In addition, DNA sequencing of the normal and mutated exons were performed. Results. Mutations in both BRCA1 and BRCA2 genes were detected in 86.7% of the families. Current study indicates that 60% of these families were attributable to BRCA1 mutations, while 26.7% of them were attributable to BRCA2 mutations. Results showed that four mutations were detected in the BRCA1 gene, while one mutation was detected in the BRCA2 gene. Asymptomatic relatives, 80(67%) out of total 120, were mutation carriers. Conclusions. BRCA1 and BRCA2 genes mutations are responsible for a significant proportion of breast cancer. BRCA mutations were found in individuals with and without family history. © 2010 Ibrahim et al; licensee BioMed Central Ltd.


El-Sersy N.A.,National Institute of Oceanography and Fisheries of Egypt | Abd-Elnaby H.,National Institute of Oceanography and Fisheries of Egypt | Abou-Elela G.M.,National Institute of Oceanography and Fisheries of Egypt | Ibrahim H.A.H.,National Institute of Oceanography and Fisheries of Egypt | El-Toukhy N.M.K.,Mubarak City for Scientific Research and Technology Applications
African Journal of Biotechnology | Year: 2010

Cellulase is a very important enzyme due to its great industrial applications. Six marine strains of actinomycetes were screened for their carboxymethyl cellulase (CMCase) productivity. Streptomyces ruber was chosen to be the best producing strain. The highest enzyme production (25.6 U/ml) was detected at pH 6 and 40°C after 7 days of incubation. Plackett-Burman design was applied to optimize the different culture conditions affecting enzyme production. Results showed that a high concentration of KH2PO4, and a low concentration of MgSO4 had a significant effect on enzyme production. Rice straw was used as a low cost source of cellulose. It was found that 30 g/l rice straw was the suitable concentration for maximum enzyme production. Partial purification of cellulase enzyme using an anionexchange chromatography resulted in the detection of two different types of CMCases, type I and II, with specific activity of 4239.697 and 846.752 U/mg, respectively. Moreover, estimation of their molecular weight revealed 27.0 kDa for cellulase type I and 24.0 kDa for cellulase type II. It could be concluded that S. ruber is a powerful cellulase producer strain under our tested experimental conditions. © 2010 Academic Journals.


Sifour M.,Jijel University | Saeed H.M.,Alexandria University | Zaghloul T.L.,Alexandria University | Berekaa M.M.,Alexandria University | Abdel-Fattah Y.R.,Mubarak City for Scientific Research and Technology Applications
Biotechnology | Year: 2010

In earlier study a new thermophilic strain Geobacillus stearothermophilus strain-5 producing thermostable lipase was isolated and identified based on 16S rRNA sequencing. Phylogenetic analysis revealed its closeness to geobacilli especially the thermophilic Geobacillus stearothermophilus with optimal growth and lipolytic enzyme activity at 60°C and pH 7.0. In this study thermostable lipase gene from this bacterium was isolated by PCR using degenerate primers. The DNA fragment coding for lipase gene was cloned in the pCR 4-TOPO plasmid and the ligation products were transformed into Escherichia coli XL1-blue cells. Partial sequencing of the gene was carried out (accession number DQ923401). Analysis by BLAST program showed some sequence similarity to that, of several lipase genes from thermophilic Geobacillus and Bacillus submitted to Genhank. © 2010 Asian Network for Scientific Information.


Abou-Elela G.M.,National Institute of Oceanography and Fisheries of Egypt | Ibrahim H.A.H.,National Institute of Oceanography and Fisheries of Egypt | Hassan S.W.,National Institute of Oceanography and Fisheries of Egypt | Abd-Elnaby H.,National Institute of Oceanography and Fisheries of Egypt | El-Toukhy N.M.K.,Mubarak City for Scientific Research and Technology Applications
African Journal of Biotechnology | Year: 2011

Among the eighteen (18) alkaliphilic marine bacterial isolates studied in ten sampling sites in Marsa-Matrouh beaches, the highest alkaliphilic and proteolytic activities were detected in Bacillus cereus. Alkaline protease from B. cereus was purified by ammonium sulfate precipitation and Sephadex G-200. The molecular mass determined using SDS-PAGE, was nearly 31.0 39 kDa. Some fundamental properties like effects of different temperatures, pH, metal ions (Ca2+, Mg2+, Cu2+, Pb3+, Mn2+ and Cd2+) and ethylene diamine tetraacetic acid (EDTA) on protease activity were also studied. Maximum activities were obtained at pH 10, 50°C and only Cu2+ ions enhanced the relative enzyme activity up to 112%. The application of alkaline protease for the removal of blood stains from cotton cloth indicates its potential use in detergent formulations. B. cereus protease showed excellent stability in the presence of locally available detergents and retained about 60% of its activity with most of them even after 3 h of incubation at temperature of 50°C. © 2011 Academic Journals.


El-Sharouny E.E.,Alexandria University | El-Toukhy N.M.K.,Mubarak City for Scientific Research and Technology Applications | El-Sersy N.A.,National Institute of Oceanography and Fisheries of Egypt | El-Gayar A.A.E.-A.,Alexandria University
Biotechnology and Biotechnological Equipment | Year: 2015

An alkaliphilic-thermotolerant Bacillus cereus N1 isolated from Bani Salama Lake, Wadi El-Natron, Egypt, was proved to produce mannanase enzyme. Optimization of the fermentation medium components using Plackett‒Burman design was applied. Glucose and inoculum size were found to be the most significant factors enhancing the production of the enzyme. On applying optimized medium in the fermentation process, an enzyme productivity of 42.2 UmL‒1 was achieved with 6.4 fold increase compared to the basal one. Mannanase was also extracted and purified using chromatography such as ionexchange chromatographic and gel filtration methods. It was indicated that, the mannanase activity extracted and purified from the isolate B. cereus N1 was reduced to 321.6 U (about 36% of the whole mannanase in the culture filtrate) in comparison with the initial mannanase activity (900 U) and the total protein content reduced to 52 mg (the initial total protein content was 220 mg). However, the specific activity for the mannanase from B. cereus N1 at the end of the purification steps was found to be about 628 Umg‒1 compared to 4.2 Umg‒1 at the initial culture filtrate. It was also indicated that the mannanase enzyme was purified almost 149-fold. © 2015 The Author(s).

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