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Chaaban I.,Alexandria University | El Khawass E.S.M.,Alexandria University | Mahran M.A.,Alexandria University | Mahran M.A.,King Abdulaziz University | And 4 more authors.
Medicinal Chemistry Research | Year: 2013

The synthesis of two novel series of quinol dimethyl ethers linked to either various functionalities or to some biologically active nitrogenous heterocycles is described. Nine of the newly synthesized quinol dimethyl ethers 5a, b, 9b, 10a, d, 12a, b, and 13a, b were selected by the NCI and were tested initially at a single high dose (10 μM) in the full NCI 60 cell panel. Four of the screened quinol dimethyl ethers bearing unsubstituted phenylhydrazone 5a, 4-chlorophenylhydrazone 5b, 4-chlorophenyl-3-sulfanyl-1,2,4-triazole 9b, as well as 4-chloroanilino-1,3,4-oxadiazole 12b moieties satisfied the threshold antitumor screen. 4-Chlorophenylhydrazone 5b showed very promising results and accordingly was chosen for in vivo antitumor screening. Thus, compound 5b of the series could be considered as the potential lead for development of novel anticancer agents. In addition, compounds 5a-c, 6a-c, 9a-c, 10a, b, d, e, g, h, 11a-c, 12a-c, and 13a-c were screened for their in vitro antimicrobial activity. Some of the tested compounds exhibited special high activity comparable to the reference ampicillin against Pseudomonas aeruginosa and Escherichia coli. © 2012 Springer Science+Business Media New York. Source


El Bestawy E.,Alexandria University | El Bestawy E.,King Abdulaziz University | Helmy S.,Alexandria University | Hussein H.,City for Scientific Research and Technology Application | Fahmy M.,City for Scientific Research and Technology Application
World Journal of Microbiology and Biotechnology | Year: 2013

The present study aimed to overcome the toxicity of the heavy metals load, discharged with the industrial effluents into Alexandria sewerage network, on the activated sludge treatment system through effective acclimation for organic matter and heavy metals removal. Optimization and/or acclimatization of the activated sludge process in the presence of Cu, Cd, Co and Cr contaminating mixed domestic-industrial wastewater was investigated. Acclimatization process was performed through abrupt and stepwise addition of tested metals using sequencing batch reactors treatment approach and evaluated as microbial oxygen uptake rate (OUR), dehydrogenase activity (DHA), organic matter (COD) and heavy metals removal. Abrupt addition of metals adversely affected sludge bioactivity leading to decline in the removal efficiency of the targeted contaminants and loss of floc structure. Metals IC50 confirmed that copper possessed the highest toxicity towards the OUR, DHA activity and COD removal with orders Cu > Cd > Cr > Co; Cu > Cd > Co = Cr and Cu > Cd > Cr > Co, respectively. The highest metal removal was recorded for Cd followed by Co, Cu and finally Cr, most of which was retained in the dissolved influent. However, controlled stepwise application of the tested metals exhibited high sensitivity of DHA and OUR activities only at the highest metal concentrations although enhanced at the lowest concentrations while COD removal was not significantly affected. In conclusion, this approach resulted in adaptation of the system where sludge microbes acquired and developed natural resistance to such metals leading to remarkable enhancement of both organic matter and heavy metals removal. © 2012 Springer Science+Business Media Dordrecht. Source


Seufi A.M.,Cairo University | Hafez E.E.,City for Scientific Research and Technology Application | Galal F.H.,Cairo University
BMC Molecular Biology | Year: 2011

Background: Defensins are a well known family of cationic antibacterial peptides (AMPs) isolated from fungi, plants, insects, mussels, birds, and various mammals. They are predominantly active against gram (+) bacteria, and a few of them are also active against gram (-) bacteria and fungi. All insect defensins belonging to the invertebrate class have a consensus motif, C-X5-16-C-X3-C-X9-10-C-X4-7-CX1-C. Only seven AMPs have already been found in different lepidopteran species. No report was published on the isolation of defensin from the Egyptian cotton leafworm, Spodoptera littoralis.Results: An anionic defensin, termed SpliDef, was isolated from the haemolymph of the cotton leafworm, S. littoralis, after bacterial challenge using differential display technique. Based on sequence analyses of the data, specific primers for full length and mature peptide of defensin were designed and successfully amplified 471 and 150 bp amplicons. The integration of the results revealed that the 471 bp-PCR product has one open reading frame (orf) of 303 bp long, including both start codon (AUG) and stop codon (UGA). The deduced peptide consists of a 23-residues signal peptide, a 27-residues propeptide and a 50-residues mature peptide with the conserved six-cysteine motif of insect defensins. Both haemolymph and expressed protein exhibited antibacterial activities comparable to positive control. The RT-qPCR indicated that it was more than 41-folds up-regulated at 48 h p.i.Conclusion: Our results highlight an important immune role of the defensin gene in Spodoptera littoralis by cooperating with other AMPs to control bacterial infection. © 2011 Seufi et al; licensee BioMed Central Ltd. Source


Seufi A.M.,Cairo University | Galal F.H.,Cairo University | Hafez E.E.,City for Scientific Research and Technology Application
PLoS ONE | Year: 2012

Background: Various proteins that display carbohydrate-binding activity in a Ca2+-dependent manner are classified into the C-type lectin family. They have one or two C-type carbohydrate-recognition domains (CRDs) composed of 110-130 amino acid residues in common. C-type lectins mediate cell adhesion, non-self recognition, and immuno-protection processes in immune responses and thus play significant roles in clearance of invaders, either as cell surface receptors for microbial carbohydrates or as soluble proteins existing in tissue fluids. The lectin of Spodoptera littoralis is still uncharacterized. Methodology: A single orf encoding a deduced polypeptide consisting of an 18-residue signal peptide and a 291-residue mature peptide, termed SpliLec, was isolated from the haemolymph of the cotton leafworm, S. littoralis, after bacterial challenge using RACE-PCR. Sequence analyses of the data revealed that SpliLec consists of two CRDs. Short-form CRD1 and long-form CRD2 are stabilized by two and three highly conserved disulfide bonds, respectively. SpliLec shares homology with some dipteran lectins suggesting possible common ancestor. The purified SpliLec exhibited a 140-kDa molecular mass with a subunit molecular mass of 35 kDa. The hemagglutination assays of the SpliLec confirmed a thermally stable, multisugar-binding C-type lectin that binds different erythrocytes. The purified SpliLec agglutinated microorganisms and exhibited comparable antimicrobial activity against gram (+) and gram (-) bacteria too. Conclusions: Our results suggested an important role of the SpliLec gene in cell adhesion and non-self recognition. It may cooperate with other AMPs in clearance of invaders of Spodoptera littoralis. © 2012 Seufi et al. Source

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