Browsing by Author "Megahed S."

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    Biomonitoring detoxification efficiency of an algal-bacterial microcosm system for treatment of coking wastewater: Harmonization between Chlorella vulgaris microalgae and wastewater microbiome
    (Elsevier B.V., 2019) Hassan M.; Essam T.; Mira A.; Megahed S.; Department of Microbiology and Immunology; Faculty of Pharmacy; Cairo University; Cairo; Egypt; Department of Genomics and Health; Center for Advanced Research in Public Health; FISABIO FoundationValencia; Spain; Department of Microbiology and Immunology; Faculty of Pharmacy; October University for Modern Sciences and Arts (MSA); Cairo; Egypt
    Nowadays, due to worldwide water shortage, water utilities are forced to re-evaluate treated wastewater. Consequently, wastewater treatment plants need to conduct biomonitoring. Coking wastewater (CWW) has toxic, mutative and carcinogenic components with threatening effect on the environment. CWW was selected as a model for complex highly toxic industrial wastewater that should be treated. CWW from Egypt was treated in a nine-liter photobioreactor using an algal-bacterial system. The photobioreactor was operated for 154 days changing different parameters (toxic load and light duration) for optimization. Optimized conditions achieved significant reduction (45%) in the operation cost. The algal-bacterial system was monitored using chemical assays (chemical oxygen demand and phenol analysis), bioassays (phytotoxicity, Artemia-toxicity, cytotoxicity, algal-bacterial ratio and settleability) and Illumina-MiSeq sequencing of 16S rRNA gene. The algal-bacterial system detoxified (in terms of phytotoxicity, cytotoxicity and Artemia-toxicity) CWW introduced as influent through all phases. A significant difference was recorded in the microbial diversity between influent and effluent samples. Four phyla dominated influent samples; Proteobacteria (77%), Firmicutes (11%), Bacteroidetes (5%) and Deferribacteres (3%) compared to only two in effluent samples; Proteobacteria (66%) and Bacteroidetes (26%). The significant relative-abundance of versatile aromatic degraders (Comamonadaceae and Pseudomonadaceae families) in influent samples conformed to the nature of CWW. Microbial community shifted and promoted the activity of catabolically versatile and xenobiotics degrading families (Chitinophagaceae and Xanthomonadaceae). Co-culture of microalgae had a positive effect on the biodegrading bacteria that was reflected by enhanced treatment efficiency, significant increase in relative abundance of bacterial genera with cyanide-decomposing potential and negative effect on waterborne pathogens. � 2019 Elsevier B.V.
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    Illumina sequencing and assessment of new cost-efficient protocol for metagenomic-DNA extraction from environmental water samples
    (Elsevier Editora Ltda, 2018) Hassan M.; Essam T.; Megahed S.; Cairo University; Faculty of Pharmacy; Department of Microbiology and Immunology; Cairo; Egypt; October University for Modern Sciences and Arts (MSA); Faculty of Pharmacy; Department of Microbiology and Immunology; Cairo; Egypt
    In this study, the development and assessment of a modified, efficient, and cost-efficient protocol for mDNA (metagenomic DNA) extraction from contaminated water samples was attempted. The efficiency of the developed protocol was investigated in comparison to a well-established commercial kit (Epicentre, Metagenomic DNA Isolation Kit for Water). The comparison was in terms of degree of shearing, yield, purity, duration, suitability for polymerase chain reaction and next-generation sequencing in addition to the quality of next-generation sequencing data. The DNA yield obtained from the developed protocol was 2.6 folds higher than that of the commercial kit. No significant difference in the alpha (Observed species, Chao1, Simpson and PD whole tree) and beta diversity was found between the DNA samples extracted by the commercial kit and the developed protocol. The number of high-quality sequences of the samples extracted by the developed method was 20% higher than those obtained by the samples processed by the kit. The developed economic protocol successfully yielded high-quality pure mDNA compatible with complex molecular applications. Thus we propose the developed protocol as a gold standard for future metagenomic studies investigating a large number of samples. � 2018 Sociedade Brasileira de Microbiologia