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Metal complexes of Schiff base 4-[(2, 4-dihydroxy-benzylidene)-amino]-1, 5-dimethyl-2-phenyl-1, 2-dihydroxo-pyrazol-3-one (H2L) derived from condensation of 2,4-dihydroxybenzaldehyde and 4-aminoantipyrine were synthesized and characterized by FT-IR spectra, elemental analysis, 1H &13C NMR, mass spectra, UV–Visible, X-ray diffraction, molar conductance, magnetic moment and thermal analysis (TGA). The elemental analysis proved that the complexes have the general formulae of [M(HL)(X)(OH2)]2, where M = Cu(II); X = OAc− (1); NO3− (2); Cl− (3), M = Co(II) (4), Mn(II) (5); X = OAc and {[UO2(HL)]2.2(OAc)}(6). According to the FT-IR spectra data, it was found that the H2L ligand is coordinated to the metal ions in a tridentate donor sites of the nitrogen atom of azomethine group, the oxygen atom of phenolic group and the oxygen atom of carbonyl group. From the measurements of magnetic susceptibility and electronic spectral data, it is found that these complexes are octahedral geometries. The trend in g value (g║ ˃ g⊥ ˃ 2.00) suggests that the unpaired electron on copper has dx2-y2 character and the complexes have an octahedral structure. By comparing the synthesized ligand (H2L) to its metal complexes was screened for their antibacterial activity against Klebsiella pneumoniae, Escherichia coli, Pseudomonas sp., Bacillus cereus and Staphylococcus aureus. It was found that the metal complexes had more potent antimicrobial than the parent Schiff base ligand against one or more microbial species. Some complexes showed higher activity than ligand. The complex (3) has antibacterial activities against Bacillus cereus, Klebsiella pneumoniae and Staphylococcus aureus. The antibacterial activity of complex (3) was the highest ones than the ligand and other complexes as well as penicillin G against Klebsiella pneumoniae. Antifungal activities were determined against Fusarium oxysporum, Aspergillus niger and Candida albicans. The inhibition efficiency of the prepared ligand (H2L) against the corrosion of carbon steel in HCl (2 M) solution was determined by various electrochemical techniques.

Roselle (Hibiscus sabdariffa L.) is one of the most crucial medicinal plants all over the world. The present study was carried out with the intention of solving some problems related to soil-borne diseases. Fusarium oxysporum is associated with wilt disease of roselle plant. The application of some microbiota i.e., a mixture of Pseudomonas fluorescens (PSR-11), Bacillus subtilis (BSR-8), Pleurotus ostreatus and mycorrhizeen® individually or in combination were investigated for controlling wilt disease, growth, and yield of roselle plant. The study was conducted in sandy textured soil under sprinkler irrigation of Ismailia Agricultural Research Station, Ismailia, Egypt. Under greenhouse conditions, all the tested bioagents reduced wilt incidence and increased the percentage of survived plants. The conglomeration of the bacterial mixture of Pseudomonas fluorescens and Bacillus subtilis, Pleurotus ostreatus and mycorrhizeen® was more effective in controlling wilt disease than using any of them individually. The application of the investigated bioagents showed a significant increase in phenol, photosynthetic pigments, and dehydrogenase contents, as well as root colonization percent. The obtained results showed the ability of B. subtilis and P. fluorescens to produce lytic enzymes such as β-1-3 glucanase, β-1-4 glucanase, chitinase and protease, in addition to their production of siderophore and HCN. The consortium of all microbiota gave the best results for growth and yield parameters of roselle plant.

Characterization of bacteriophages facilitates better understanding of their biology, host specificity, genomic diversity, and adaptation to their bacterial hosts. This, in turn, is important for the exploitation of phages for therapeutic purposes, as the use of uncharacterized phages may lead to treatment failure. The present study describes the isolation and characterization of a bacteriophage effective against the important clinical pathogen Escherichia coli, which shows increasing accumulation of antibiotic resistance. Phage fEg-Eco19, which is specific for a clinical E. coli strain, was isolated from an Egyptian sewage sample. Phage fEg-Eco19 formed clear, sharp-edged, round plaques. Electron microscopy showed that the isolated phage is tailed and therefore belongs to the order Caudovirales, and morphologically, it resembles siphoviruses. The diameter of the icosahedral head of fEg-Eco19 is 68 ± 2 nm, and the non-contractile tail length and diameter are 118 ± 0.2 and 13 ± 0.6 nm, respectively. The host range of the phage was found to be narrow, as it infected only two out of 137 clinical E. coli strains tested. The phage genome is 45,805 bp in length with a GC content of 50.3% and contains 76 predicted genes. Comparison of predicted and experimental restriction digestion patterns allowed rough mapping of the physical ends of the phage genome, which was confirmed using the PhageTerm tool. Annotation of the predicted genes revealed gene products belonging to several functional groups, including regulatory proteins, DNA packaging and phage structural proteins, host lysis proteins, and proteins involved in DNA/RNA metabolism and replication.

Background Hypertrophy of the nucleolus is a distinctive cytological feature of malignant cells and corresponds to aggressive behaviour. This study aimed to identify the key gene associated with nucleolar prominence (NP) in breast cancer (BC) and determine its prognostic significance. Methods From The Cancer Genome Atlas (TCGA) cohort, digital whole slide images identified cancers having NP served as label and an information theory algorithm was applied to find which mRNA gene best explained NP. Dyskerin Pseudouridine Synthase 1 (DKC1) was identified. DKC1 expression was assessed using mRNA data of Molecular Taxonomy of Breast Cancer International Consortium (METABRIC, n = 1980) and TCGA (n = 855). DKC1 protein expression was assessed using immunohistochemistry in Nottingham BC cohort (n = 943). Results Nuclear and nucleolar expressions of DKC1 protein were significantly associated with higher tumour grade (p p p DKC1 mRNA and protein expressions were independent risk factors for BCSS (p Conclusion DKC1 expression is strongly correlated with NP and its overexpression in BC is associated with unfavourable clinicopathological characteristics and poor outcome. This has been a detailed example in the correlation of phenotype with genotype.

Green synthesized nanoparticles are more advantageous over conventionally prepared ones due to less toxicity, production cost, and environmental hazards. With the widespread of the utilization of nanoparticles, little is known about the maternal-fetal transplacental transfer of green nanoparticles. We have biosynthesized silver nanoparticles using metabolites of Streptomyces malachitus and sunlight then coated them with chitosan. These nanoparticles have been characterized and intraperitoneally administered at doses of 100 mg/kg on the 6th, 8th, and 10th gestational days. On the 18th day of pregnancy, both coated and non-coted NPs were detected in different maternal tissues, placenta, and in fetuses, as determined by estimation of silver content and observation by electron microscopy. Chitosan coating decreased the silver content in different tissues, maybe due to the larger size of coated nanoparticles that retards the transfer. The toxic effects on maternal and fetal tissues were proportional to their silver content, as determined by the liver and kidney functional analysis of pregnant rats and the ultrastructural and histopathological examination of the maternal liver, placenta and fetal liver. The present data suggest that green silver nanoparticles biosynthesized by Streptomyces malachitus cross the placenta and have toxic effects on maternal tissues, placenta, and fetus. Chitosan coating of these nanoparticles decreases the transfer, and consequently, the toxicity. However, it does not prevent this toxicity.

Members of the family Enterobacteriaceae aremajor pathogens associated with gastrointestinal disorderscaused by the consumption of contaminated foods. This study developed a multiplex PCR targetingspecific genes for simultaneous detection and differentiationof seven major Enterobacteriaceae members, namely,Escherichia coli (uidA), Proteussp. (atpD), Salmonella sp. (invA), Enterobacter sp. (16S rRNA), Klebsiella sp. (gyrA), Klebsiella pneumoniae (rpoB) and K. oxytoca (pehX) from contaminated food samples. Four main types of food samples comprise fresh, frozen, processed frozen and processed preserved samples were examined by using simultaneous amplification of those seven-targeted genes from obtained reference strains. The multiplex PCR assay showed detection sensitivity reached 5-10 cfu for each pathogen after 2h of sample incubation on nutrient broth. Generally, the 7plex-PCR assay revealed that the most common pathogens found in 192 different food samples with high frequency was Salmonella which distributed within most of all types of food having the maximum occurrence frequency reached 6.77% in hotdog and sausage samples followed by 5.21% in fresh chicken and beef burger. The occurrence frequency % of E. coli was found to be high in chicken/beef burger samples (6.25%), and then slightly decreased to 5.21%, 4.68% and 4.17% in frozen meat, hotdog/sausage and fresh fish samples, respectively. The processed preserved (chicken/beef luncheon and pastrami) and frozen chicken possessed the lowest presence of foodborne pathogens. This study recommends the use of 7plex-PCR detection system for the rapid and accurate detection of some Enterobacteriaceae pathogens is inexpensively and thus could be used for the regular monitoring of food quality.

The present study was focused on isolation and screening of tyrosinase enzyme produced by actinomycetes. The isolates were primarily identified to genus level on the basis of their microscopic and cultural characteristics. Biochemical and other characters were used to identify isolates to species level. A total five soil samples were collected from different sites at Damietta EL-Gededa (Egypt) and Meslatah (Libya). The total 36actinomycete isolates were obtained from soil by performing serial dilution technique and using starch-nitrate agar and primary screened for tyrosinase production by using tyrosine agar medium. Based on the result of primary screening,8 isolates 2D, 4D, 5L, 6L, 12D, 13D, 14D and 26L showed blackish brown pigment development due to melanin production, was selected. These isolates were taken for secondary screening(tyrosinase assay) by culturing on tyrosine broth at 30OC for 5 days. Greenish black color was reported in tyrosine broth indicated the positive tyrosinase activity. Out of them, isolates13D,14D and 26Lwhich showed the highest tyrosinase activities (1.2 U/ml, 4.8 U/mL and 8.4 U/mL, respectively) were identified on the basis ofcultural, morphological, physiological, biochemical as Streptomyces malachitorectus, Streptomycesiakyrus and Streptomycesechinatus, respectively.

Characterization of bacteriophages facilitates better understanding of their biology, host specificity, genomic diversity, and adaptation to their bacterial hosts. This, in turn, is important for the exploitation of phages for therapeutic purposes, as the use of uncharacterized phages may lead to treatment failure. The present study describes the isolation and characterization of a bacteriophage effective against the important clinical pathogen Escherichia coli, which shows increasing accumulation of antibiotic resistance. Phage fEg-Eco19, which is specific for a clinical E. coli strain, was isolated from an Egyptian sewage sample. Phage fEg-Eco19 formed clear, sharp-edged, round plaques. Electron microscopy showed that the isolated phage is tailed and therefore belongs to the order Caudovirales, and morphologically, it resembles siphoviruses. The diameter of the icosahedral head of fEg-Eco19 is 68 ± 2 nm, and the non-contractile tail length and diameter are 118 ± 0.2 and 13 ± 0.6 nm, respectively. The host range of the phage was found to be narrow, as it infected only two out of 137 clinical E. coli strains tested. The phage genome is 45,805 bp in length with a GC content of 50.3% and contains 76 predicted genes. Comparison of predicted and experimental restriction digestion patterns allowed rough mapping of the physical ends of the phage genome, which was confirmed using the PhageTerm tool. Annotation of the predicted genes revealed gene products belonging to several functional groups, including regulatory proteins, DNA packaging and phage structural proteins, host lysis proteins, and proteins involved in DNA/RNA metabolism and replication.

L-asparaginase is used as an antileukemic drug and as a food additive to reduce the risk of acrylamide formation. New L-asparaginases are required to reduce costs and avoid clinical side effects. Citrobacter freundii EGY-NE1represents a potential source of new L-asparaginase. We purified extracellular L-asparaginase from Citrobacter freundii EGY-NE1 (through ammonium sulfate precipitation, dialysis, Sephadex-G50 and DEAE-cellulose columns) to 5.83 fold and 25.76 % recovery. The purified L-asparaginase was a low molecular weight enzyme of 19 kDa. It was optimally active at 37 ˚C, pH 8 and 40 mM asparagine. The Km and Vmax of the enzyme were 0.0179 M and 2.66 U/ml, respectively. Ca2+, Mg2+, K+ and Ba+ 2 activated the enzyme, while Na+, Zn+ 2, EDTA, azide, tartrate and HgCl2 inhibited it. The crude and purified enzymes were immobilized by encapsulation in Ca-alginate; this improved their stability and reusability. The entrapped L-asparaginases on Ca-alginate were examined by scanning electron microscope; their protein diameters ranged from 42.17 to 47.37 nm and from 46.78 to 71.97 nm for the immobilized crude and purified enzymes, respectively. Both the immobilized enzymes kept their maximal activity for 10 minutes at 40 ˚C. After the 5th cycle of repeated use, the immobilized purified and crude enzymes kept 91% and 89 % of their activities, respectively.

This study explored the applicability of using TaqMan qPCR (quantitative polymerase chain reaction) for Escherichia coli, Salmonella enterica and non-virulent Vibrio cholerae detection in surface and drinking water. One hundred and twenty water samples were collected monthly (January 2017–December 2017) from the surface water (input) and drinking water (output and distribution networks) of two drinking water treatment plants (DWTPs) in Damietta County, Egypt. The distribution of the studied bacteria based on their detection by TaqMan qPCR compared with membrane filtration (MF) technique showed that the higher positive samples were detected by TaqMan qPCR. The bacterial count was totally absent in all output samples. TaqMan qPCR assay (based on sequence detection of uidA, invA, and ompW) revealed 97.96%, 99.14%, and 98.3% specificity for E. coli, S. enterica, and non-virulent V. cholerae, respectively, compared with 100% specificity for all strains when MF cultures were applied. TaqMan qPCR exhibited 100% sensitivity for all strains, while it was 91.67%, 80%, and 50% using MF cultures for E. coli, S. enterica, and non-virulent V. cholerae, respectively. In conclusion, TaqMan qPCR sensitivity makes it a useful tool for urgent fast monitoring of water contamination, especially in network samples that contain low bacterial count.

Conventional antifungal agents have failed to treat several infectious diseases of many Aspergillus strains. These strains have been linked to the production of high-potency mycotoxins, which cause mould diseases on fruits and vegetables and have negative health consequences. The current study aimed to develop new effective nanomaterials using efficient methods that were stable and antifungal. The current work has been carried out to use the free cell supernatant of Escherichia coli D8 (MF062579) in the biosynthesis of reduced graphene oxide/silver nanocomposite (rGO/AgNC). At room temperature, the nanocomposite was prepared by an economical and simple one-step approach. Different parameters were optimized in the biofabrication of rGO/AgNC such as silver nitrate concentration, bacterial supernatant concentration, pH value, and temperature. Ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Zeta analyses were used to evaluate the optimized rGO/AgNC. The biosynthesis process was performed within minutes in the incidence of solar irradiation. The mean size of silver nanoparticles (AgNPs) was estimated to be 9-18 nm. The biogenesis of spherical-shaped, well-dispersed AgNPs was validated by TEM images. AgNPs have a positive potential value, as seen by the zeta potential graph. rGO/AgNC had a harmful effect on the ultrastructure of rGO/AgNC-treated Aspergillus including membranes damage, malformation, and complete lysis of fungal cells in addition to enzymatic inhibition in lactate dehydrogenase activity. This study states a well-designed approach to develop a new antimicrobial agent, rGO/AgNC, against pathogenic human and phytopathogenic Aspergillus spp. in addition to a probable mechanism for the nanomaterial’s antimicrobial action.

Acinetobacter baumannii is an opportunistic pathogen that presents a serious clinical challenge due to its increasing resistance to all available antibiotics. Phage therapy has been introduced recently to treat antibiotic-incurable A. baumannii infections. In search for new A. baumannii specific bacteriophages, 20 clinical A. baumannii strains were used in two pools in an attempt to enrich phages from sewage. The enrichment resulted in induction of resident prophage(s) and three temperate bacteriophages, named vB_AbaS_fEg-Aba01, vB_AbaS_fLi-Aba02 and vB_AbaS_fLi-Aba03, all able to infect only one strain (#6597) of the 20 clinical strains, were isolated. Morphological characteristics obtained by transmission electron microscopy together with the genomic information revealed that the phages belong to the family Siphoviridae. The ca. 35 kb genomic sequences of the phages were &gt, 99% identical to each other. The linear ds DNA genomes of the phages contained 10 nt cohesive end termini, 52-54 predicted genes, an attP site and one tRNA gene each. A database search revealed an &gt, 99% identical prophage in the genome of A. baumannii strain AbPK1 (acc. no. CP024576.1). Over 99% identical prophages were also identified from two of the original 20 clinical strains (#5707 and #5920) and both were shown to be spontaneously inducible, thus very likely being the origins of the isolated phages. The phage vB_AbaS_fEg-Aba01 was also able to lysogenize the susceptible strain #6597 demonstrating that it was fully functional. The phages showed a very narrow host range infecting only two A. baumannii strains. In conclusion, we have isolated and characterized three novel temperate Siphoviridae phages that infect A. baumannii.

Antimicrobial targets should be essential to the life or pathogenicity of bacteria and contain conserved target binding regions. This chapter reviews the antimicrobial target sites, their structures, roles, and their inhibition. Life-essential targets include FtsZ and their regulatory proteins; they mediate the cell division and its accompanying modifications in the cell wall. Peptidoglycan biosynthesis enzymes also belong to life-essential targets; we focused on the integral membrane protein MraY, the membrane-associated protein MurG, and penicillin-binding proteins (PBPs) rather than Mur enzymes due to their in vivo inaccessibility. Targeting DNA, as an essential element, may damage the strands or interfere with the replication mechanisms, or even specific genes; sequence-specific binders are designed. For expanding the drug targets, bacterial quorum sensing systems (QSs) are targeted; it regulates several genes; we reviewed the quorum quenching through several approaches. Other targets would provide new anti-virulence drugs. The d-alanylation of teichoic acid represents a potential target in Gram-positive bacteria; we discussed the specificity and inter-species conservation of the key enzyme (d-Alanyl carrier protein ligase) in this pathway.

Mixed ligand complexes of Cu(II), Co(II), Ni(II), Mn(II) and Cd(II) with N,N'-1,4-phenylene (2-hyboxynaphthaliden imine) (H2L) as primary ligand and 4-aminoantipyrine (4-AAp) as secondary ligand have been prepared. The newly formed complexes were characterized using elemental analysis, magnetic susceptibility, molar conductance, 1H NMR, UV–Vis., FTIR, X-ray diffraction, mass, thermal analysis and ESR techniques. The elemental analysis, data reveal the formation of [2:1:2] [M: H2L: 4-AAP] complexes. The mode of bonding between Cu(II), Ni(II), Co(Il), Mn(II) and Cd(II) and ligands has been studied by IR spectrophotometry. Electronic absorption spectra and magnetic moment measurements of the mixed-ligand complexes suggest a distorted octahedral geometry around the central metal ion and the anions X− are in the axial positions, for all compounds. The ligands are found to behave in a neutral bidentate manner, through nitrogen atom and oxygen atom of carbonyl group (secondary ligand), whereas H2L (primary ligand) coordinated through nitrogen and OH group as a neutral ligand. FT-IR spectral data shows that the ligand acted as bis-bidentate coordination through ON–NO donor system. The XRD patterns of the ligand and its mixed ligand complexes showed the polycrystalline natures. The ligand and its mixed complexes were studied for their microbial activity against some bacteria and fungi. The ligand in comparison to its mixed ligand complexes (1-5) was screened for their antibacterial activity against Klebsiella pneumoniae, Escherichia coli, Pseudomonas sp., Staphylococcus aureus and Bacillus cereus. Antifungal activities of ligand in comparison to its mixed ligand complexes (1-5) were determined against Fusarium oxysporum, Aspergillus niger and Candida albicans. It was found that the mixed ligand complex (5) is more active than other mixed ligand complexes and penicillin G against Bacillus cereus, Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas sp. The mixed ligand complex (5) is more active than the ligand and other mixed ligand complexes and miconazole against Aspergillus niger. The inhibition efficiency of the prepared ligand (H2L) against the corrosion of P355 carbon steel in HCl (2 M) solution was determined by various electrochemical methods are found to be in reasonable agreement. The morphology of protected P355 carbon steel was test by energy dispersive X-ray and scanning electron microscope (EDX–SEM).

This study was concerned with the isolation of bacterial strains from different water sources. Among these strains; Enterobacter sp. exhibited extracellularly biosynthesized silver nanoparticles with good monodispersity. Enterobacter sp. has produced extremely stable nanoparticles within 72 hrs at 35°C in dark conditions. These nanoparticles are characterized by UV–vis spectrophotometer, transmission electron microscopy, Zeta potential analyzer, and size distribution by volume. Enterobacter sp. synthesized 9.45-17.15 nm sized spherical shaped silver nanoparticles. The presence and binding of stabilized proteins with nanoparticles were confirmed by the zeta size distribution by volume. Our study demonstrates that silver nanoparticles are potent inhibitors of the plant pathogenic fungus, Fusarium oxysporum f. sp. lycopersici.

A novel bis-bidentate azo dye ligand, formed by the diazotized reaction of 1,4-diaminobenzene and 8- hydroxyquinoline in 1:2 M ratio resulted the formation of 5,5′-{(1E, 1E`)-1,4-phenylenebis(diazene-2,1-diyl)}bis(quinoline-8-ol) (H2L1) as primary ligand and its Cu(II), Ni(II), Co(II), Mn(II), Cr(III), UO2(II) and Cd(II) complexes. Incorporating of 8-hydroxyquinoline (HL2) as co-ligand with the formed mixed-ligand complexes of the composition, [M2(L1)(L2)2(OH2)4] (M = Cu(II), Co(II), Ni(II), Mn(II), UO2(II), Cd(II) and [Cr2(L1)(L2)2(OH2)2(Cl2)] were synthesized and characterized. H2L1, HL2, and their mixed ligand complexes were screened against two local gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and three local gram-negative bacteria (Klebsiella pneumoniae Escherichia coli and Pseudomonas sp). Antifungal activities were determined against Fusarium oxysporum Aspergillus niger, and Candida albicans. Cr(III), Mn(II) and UO2(II) mixed ligand complexes showed higher activity than H2L1 and HL2; their cytological effects on S. aureus and B. cereus along with the in-silico docking showed that these complexes represent antibacterials targeting FtsZ and DltA proteins; hence, affect cell divisions and gram-positive cell walls. The XRD patterns of the Mn(II) and UO2(II) mixed ligand complexes are polycrystalline natures.

P HYTOGENIC mounds (nebkhas) formed by halophytes are widely distributed in coastal and desert environments. Such nebkhas provide loci for geochemical and biological activities that influence ecosystem processes and function. Seasonal variation in soil and bacterial properties were investigated within the nebkhas under the canopy of Halocnemum strobilaceum and in the surrounding unvegetated sites at salt marshes of Lake Manzala. The parameters measured include soil moisture, organic matter, total nitrogen and phosphorus, pH, electrical conductivity (EC), and bacterial community and enzyme characteristics. Enrichment ratios for soil salinity and nutrients were evaluated to indicate the salinity and fertility islands within nebkhas. Soil moisture content showed significant differences between the different seasons with the highest value in winter (16.55%) at unvegetated control site.Soil electrical conductivity, total nitrogen and phosphorus had their significantly higher values in nebkhas during autumn. The enrichment values for the measured soil parameters ranged from 0.31 to 4.09 in the four seasons which indicates a clear accumulation effect for soil nutrients and salts within the nebkhas under the canopy of H. strobilaceum. Bacterial abundance was consistently higher in nebkhas through all seasons. Eleven genera of bacteria belong to Firmicutes, Actinobacteria and proteobacteria phyla were recorded in nebkha and unvegetated sites. These genera varied in their occurrence between the two locations and the four seasons. It can be concluded that the formation of nebkhas by halophytic vegetation have noticeable effects on accumulation of soil salinity and fertility during different seasons that affect bacterial abundance and activity in coastal environment.

Allyl isothiocyanate (AITC) is a natural occurring essential oil found in plants of the family Brassicaceae. It is a well-recognized antimicrobial agent against a variety of foodborne pathogens. By vapor and solution deposition methods into raw and de-oiled Laminaria japonica, an edible, brown seaweed, we demonstrate AITC vapor phase activity against Listeria monocytogenes, Bacillus subtilis, and Micrococcus luteus. Colony deactivation occurred for each bacterium in the range 99.87–99.99% within 72 h. The kinetics of these activities was fitted to the Weibull and the Albert-Mafart population decay models. Combined standard uncertainty in the final model fitting is introduced for these models, along with bias factor analysis. The former indicates the degree of fit of the models while the latter indicated which of the models was the most appropriate. In general, the bias factor analysis of the models indicated that the Albert-Mafart model was the superior. The continued activity of AITC after contact with the seaweed delivery system suggested that the L. japonica + AITC system would represent a viable natural, edible system for food preservation.

In comparison between the eastern and western coasts of the Mediterranean Sea of Egypt, water samples were collected seasonally from Port Fouad City and Damietta branch of the Nile River during four successive seasons. Water samples were tested for some physical and chemical parameters including: water turbidity, TSS and chlorophyll-a as well as the determination of water salinity, pH, concentrations of some nutrient salts and trace metals such as: Cl-, Na+, K+, Mg+2, Ca+2, PO4-3, NO3-, SO4-2, Fe+3, Cu+2, Zn+2 and Mn+2. Total bacterial counts of collected water samples were determined as well as biochemical identification of 17 bacterial genera. Results showed that the western coast of the Egyptian Mediterranean Sea recorded higher salinity values and higher concentrations of Cl- ions than those recorded in the eastern coast represented in Port Fouad City. Water turbidity values showed strong positive significant correlations between Alexandria and Port Fouad as well as Port Fouad and the Nile River while non-significant correlations occurred between water turbidity of Alexandria site and the Nile River site.

Metal(II) complexes of 4-(((2-hydroxynaphthalen-1-yl)methylene)amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (HL) were prepared, and their compositions and physicochemical properties were characterized on the basis of elemental analysis, with1HNMR, UV–Vis, IR, mass spectroscopy and thermogravimetric analysis. All results confirm that the novel complexes have a 1:1 (M:HL) stoichiometric formulae [M(HL)Cl2] (M = Cu(II)(1), Cd(II)(5)), [Cu(L)(O2NO)(OH2)2](2), [Cu(HL)(OSO3)(OH2)3]2H2O(3), [Co(HL)Cl2(OH2)2]3H2O(4), and the ligand behaves as a neutral/monobasic bidentate/tridentate forming a five/six-membered chelating ring towards the metal ions, bonding through azomethine nitrogen, exocyclic carbonyl oxygen, and/or deprotonated phenolic oxygen atoms. The XRD studies show that both the ligand and Cu(II) complex (1) show polycrystalline with monoclinic crystal structure. The molar conductivities show that all the complexes are non-electrolytes. On the basis of electronic spectral data and magnetic susceptibility measurements, a suitable geometry has been proposed. The trend in g values (g ll > g ⊥ > 2.0023) suggest that the unpaired electron on copper has a $$d_{{x^{2} - y^{2} }}$$ character, and the complex (1) has a square planar, while complexes (2) and (3) have a tetragonal distorted octahedral geometry. The molecular and electronic structures of the ligand (HL) and its complexes (1–5) have been discussed. Molecular docking was used to predict the binding between HL ligand and the receptors of the crystal structure of Escherichia coli (E. coli) (3t88) and the crystal structure of Staphylococcus aureus (S. aureus) (3q8u). The activation thermodynamic parameters, such as activation energy (E a), enthalpy (ΔH), entropy (ΔS), and Gibbs free energy change of the decomposition (ΔG) are calculated using Coats–Redfern and Horowitz–Metzger methods. The ligand and its metal complexes (1–5) showed antimicrobial activity against bacterial species such as Gram positive bacteria (Bacillus cereus and S. aureus), Gram negative bacteria (E. coli and Klebsiella pneumoniae) and fungi (Aspergillus niger and Alternaria alternata); the complexes exhibited higher activity than the ligand.

Metal(II) complexes of 3-[(2-hydroxy-3-methoxybenzylidene)hydrazo]-1,3-dihydroindol-2-one (HL) were prepared, their compositions and physicochemical properties were characterized on the basis of elemental analysis, molar conductivity, 1 H NMR, UV–Vis, IR, mass spectroscopy, X-ray, magnetic measurements and thermogravimetric analysis (TGA). All results confirm that the novel complexes have 1:1 metal-to-ligand stoichiometric formulae [M(HL)(OAc) 2 (OH 2 ) 2 ] (M Cu(II)( 1 ), Co(II)( 2 ), Ni(II)( 3 ) and Cd(II)( 4 )), octahedral configuration and the ligand behaves as a neutral bidentate forming six-membered chelating ring towards the metal ions, bonding through azomethine nitrogen and ketonic oxygen atoms. The molecular structures of the ligand and its metal complexes were also studied using quantum chemical calculations and shows that the keto form with hydrogen bond is more stable than other forms. The coordination geometry around all complexes ( 1 – 4 ) exhibits an octahedral geometry. The XRD studies show that both the ligand and Cu(II) complex show polycrystalline with Triclinic crystal system. The activation thermodynamic parameters, such as activation energy (E a ), enthalpy (ΔH), entropy (ΔS), and Gibbs free energy change of the decomposition (ΔG) are calculated using Coats–Redfern and Horowitz–Metzger methods. The ligand and its metal complexes ( 1 – 4 ) showed antimicrobial activity against bacterial species, Gram positive ( Staphylococcus aureus ), Gram negative ( Escherichia coli ) bacteria and yeast ( Candida albicans ), the ligand exhibited higher activity than the complexes. All investigated compounds were screened in vitro for their antioxidant, cytotoxic and antitumor activity. Molecular docking was used to predict the binding between HL ligand and the receptors of crystal structure of E. coli (3T88), crystal structure of S. aureus (3q8u) and crystal structure of C. albicans (1Q40).

This study aimed to compare and analyze the results of microbiological and immunological laboratory investigations of pulmonary tuberculosis and non-tuberculosis patients from Hospitals at Saudi Arabia, and also to evaluate the serodiagnosis detection of tuberculosis promptly using immunological assays in comparison with the traditional Ziehl Neelsen microbiological techniques. This is to develop reliable, effective assay, shorter duration and more specific diagnosis of active tuberculosis. The sensitivity, specificity and efficiency of Ziehl-Neelsen stain were 48 %, 100 % and 64 %, respectively. An identified antigen in serum samples of infected persons with pulmonary tuberculosis was detected using TB-Spot ELISA technique. The sensitivity, specificity and efficiency of TB-Spot ELISA for the detection of antigen were 97 %, 95 % and 98 %, respectively. The serum levels of TNF-α reach statistical difference (P< 0.0001) in patients positive for TB antigen in comparison with the levels in negative individuals for TB.

Twenty marine actinomycetes were isolated from sediments and rhizosphere of some halophyte plants from coastal regions of North Delta, Egypt. Four isolates which showed a wide range of antimicrobial activities (inhibition for both Gram-positive and Gram-negative bacteria, and fungi) were selected and identified on the basis of their cellular morphology, physiological and chemotaxonomic characterization. The isolates were identified and named as Streptomyces albus strain DEG18, Streptomyces canaries strain REB9, Streptomyces sp strain REB5 and Streptomyces sp strain G12. Extraction of metabolites filtrate and biomass were carried out by ethyl acetate and acetone, respectively. In secondary screening, all four Streptomyces strains showed antibacterial activity against Enterobacter cloaca and antifungal activity toward Fusarium oxysporum, three strains out of them showed antibacterial activity against Bacillus cereus, whereas two showed activity against Bacillus subtilis and Staphylococcus aureus, whereas some strains showed activity toward Klebsiella pneumoniae and Alternaria alternata.

Residents in many developing countries store treated drinking water in tanks or reservoirs because of intermittent and infrequent water supplies. Many studies have focused on bacterial contamination of domestic reservoir waters, the cyanobacterial and algal contamination is largely unexplored. Therefore, the present study investigates toxic cyanobacteria and their microcystin (MC) toxins in some domestic water storage reservoirs in Egypt as an example for developing countries. Three phytoplankton groups including cyanobacteria, green algae and diatoms were found in domestic reservoirs. Among these species, the toxic cyanobacterium Microcystis aeruginosa had the highest cell density during warm months (4.2–5.92 cells × 106 L–1). This cell density increased along the time, indicating that environmental conditions in these reservoirs promoted the proliferation of this species. Intra- and extracellular MCs were also detected in reservoir waters at concentrations of 3.5–40 and 1–7.6 μg L–1, respectively, exceeding the WHO guideline limit of 1 μg L–1 for these toxins in drinking water. Heterotrophic bacteria were found in association with cyanobacteria in reservoir waters. The study suggests that treated-water storage reservoirs should be monitored for the presence of toxic cyanobacteria to protect the public from exposure to their potent toxins.

A novel bis-bidentate azo dye ligand, formed by the diazotized reaction of 1,4-diaminobenzene and 8-hydroxyquinoline in 1:2 M ratio resulted the formation of 5,5'-{(1E, 1E′)-1,4-phenylenebis(diazene-2,1-diyl)}bis(quinolin-8-ol) (H2L1) as primary ligand and its Cu(II), Ni(II), Co(II), Mn(II), Cr(III), UO2(II) and Cd(II) complexes. Incorporating of 8-hydroxyquinoline (HL2) as co-ligand with the formed mixed-ligand complexes were synthesized and characterized using elemental analysis, FT IR, 1 H NMR, UV–visible and mass spectroscopy as well as molar conductance, magnetic measurements, solid reflectance, thermal analysis, electron spin resonance and X-ray diffraction. From elemental and spectral data, the formulae [M2(L1)(L2)2(OH2)4] (where M = Cu(II) (1), Co(II) (2), Ni(II) (3), Mn(II) (4), UO2(II) (6), Cd(II) (7)) and [Cr2(L1)(L2)2(H2O)2(Cl)2] (5) for the metal complexes have been proposed. The geometric structures of the mixed-ligand complexes were found to be octahedral and the XRD patterns showed the polycrystalline natures. The bond lengths, bond angles, the highest occupied molecular orbital energy, the lowest unoccupied molecular orbital energy and quantum chemical parameters were calculated to confirm the geometry of the mixed-ligand complexes (1–5 & 7). The molecular docking was used to predict the efficiency of binding between mixed-ligand complexes (1–7) with receptor of the prostate cancer (PDB code: 2q7k). The theoretical study was used to calculate the HOMO–LUMO energies gap (ΔE) for mixed-ligand complexes (1–5 & 7).

AmyLa α-amylase gene from Laceyella sp. DS3 was heterologously expressed in E. coli BL21. E. coli BL21 maximally expressed AmyLa after 4 h of adding 0.02 mM IPTG at 37 °C. The recombinant AmyLa α-amylase was purified 2.19-fold through gel filtration and ion exchange chromatography. We immobilized the purified recombinant AmyLa α-amylase on four carriers; chitosan had the best efficiency. The recombinant free and the immobilized AmyLa α-amylase showed optimum activity in the pH ranges of 6.0–7.0 and 4.0–7.0, respectively and possessed an optimum temperature of 55 °C. The free enzyme had activation energy, Km, and Vmax of 291.5 kJ, 1.5 mg/ml, and 6.06 mg/min, respectively. The immobilized enzyme had activation energy, Km, and Vmax of 309.74 kJ, 6.67 mg/ml, and 50 mg/min, respectively. The immobilized enzyme was calcium-independent and insensitive (relative to the free enzyme) to metals. It could also be reused for seven cycles.

3-Allyl-5-(4-arylazo)-2-thioxothiazolidine-4-one (HLn ) ligands (where n = 1 to 3) were hypothesized to have antimicrobial activities mediated through inhibition of new antimicrobial targets. The ligands (HLn ) were synthesized and characterized by infrared (IR) and 1 H nuclear magnetic resonance (1 H NMR) spectra. The ligands (HLn ) were in silico screened to their potential inhibition to models of d-alanyl carrier protein ligase (DltA) (from Bacillus cereus, PDB code 3FCE) and nucleoside diphosphate kinase (NDK) (from Staphylococcus aureus; PDB code 3Q8U). HL3 ligand has the best energy and mode of binding to both NDK and DltA, even though its binding to DltA was stronger than that to NDK. In antimicrobial activity of HL3 ligand, morphological and cytological changes in HL3 -treated bacteria agreed with the in silico results. The HL3 ligand showed significant antimicrobial activity against B. cereus, S. aureus, and Fusarium oxysporium. The HL3 -treated bacterial cells appeared malformed and incompletely separated. Its cell walls appeared electron-lucent and ruptured. They contained more mesosomes than normal cells. It was found that the HL3 ligand represented as a bactericide against B. cereus and S. aureusby blocking target DltA, and may target NDK.

Monitoring of cyanobacteria and their associated toxins has intensified in raw water sources of drinking water treatment plants (WTPs) in most countries of the world. However, it is not explored yet for Egyptian WTPs. Therefore, this study was undertaken to investigate the occurrence of cyanobacteria and their microcystin (MC) toxins in the Nile River source water of Damietta WTP during warm months (April-September 2013) and to evaluate the removal efficiency of both cyanobacterial cells and MCs by conventional methods used in this plant as a representative of Egyptian drinking WTPs. The results showed that the source water at the intake of Damietta WTP contained dense cyanobacterial population (1.1-6.6 × 107 cells L(-1)) dominated by Microcystis aeruginosa. This bloom was found to produce MC-RR and MC-LR. Both cyanobacterial cell density and intracellular MCs in the intake source water increased with the increase in temperature and nutrients during the study period, with maximum values obtained in August. During treatment processes, cyanobacterial cells were incompletely removed by coagulation/flocculation/sedimentation (C/F/S; 91-96.8%) or sand filtration (93.3-98.9%). Coagulation/flocculation induced the release of MCs into the ambient water, and the toxins were not completely removed or degraded during further treatment stages (filtration and chlorination). MCs in outflow tank water were detected in high concentrations (1.1-3.6 μg L - 1), exceeding WHO provisional guideline value of 1 μg L - 1 for MC-LR in drinking water. Based on this study, regular monitoring of cyanobacteria and their cyanotoxins in the intake source water and at different stages at all WTPs is necessary to provide safe drinking water to consumers or to prevent exposure of consumers to hazardous cyanobacterial metabolites.

Two mesophilic streptomycetes (S. violaceoruber and S. spiroverticillatus) were selected to study their Poly R-478 decolorization ability and lignocellulose solubilizing activity. Both strains were able to degrade Poly R-478 dye and ferulic acid during growth on a minimal salts medium. The Poly R-478 decolorizing activities of both strains were induced by adding different carbon sources to the culture media. S. violaceoruber could decolorize 63% of Poly R-478 after 24 h. Both strains could solubilize straw and produce acid-precipitable polymeric lignin (APPL) with different efficiency. From the major extracellular enzymes recovery of both strains on rice and wheat straw, we can predicate that the biodegradation process was partial indicating a possible utilization in biological delignification.

The Cu2+, Co2+, Ni2+ and UO22+ polymer complexes of 5-(2,3-dimethyl−1-phenylpyrazol-5-one azo)-8-hydroxyquinoline (HL) ligand were prepared and characterized. Elemental analyses, IR spectra, X-ray diffraction analysis and thermal analysis studies have been used to confirm the structure of the prepared polymer complexes. The chemical structure of metal chelates commensurate that the ligand acts as a neutral bis(bidentate) by through four sites of coordination (azo dye nitrogen, carbonyl oxygen, phenolic oxygen and hetero nitrogen from pyridine ring). The molecular and electronic structures of the hydrogen bond conformers of HL ligand were optimized theoretically and the quantum chemical parameters were calculated. Elemental analysis data suggested that the polymer complexes have composition of octahedral geometry for all the polymer complexes. Molecular docking of the binding between HL and the receptors of prostate cancer (PDB code 2Q7L Hormone) and the breast cancer (PDB code 1JNX Gene regulation) was studied. The interaction between HL and its polymer complexes with the calf thymus DNA (CT-DNA) was determined by absorption spectra. The antimicrobial activity of HL and its Cu2+, Co2+, Ni2+ and UO22+ polymer complexes were investigated; only Cu(II) polymer complex (1) was specifically active against Aspergillus niger. It inhibited the fungal sporulation and distorted the fungal mycelia, which became squashed at a concentration of 150 μg/ml; transmission electron microscope (TEM) also showed a deactivation of autophagy in the treated A. niger cells via accumulation of autophagic bodies in vacuoles. The inhibition process of the prepared ligand (HL) against the corrosion of carbon steel in 2 M HCl solution was determined by various methods (weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques) are found to be in reasonable agreement. The mechanism of inhibition in presence of HL in carbon steel corrosion obeys Friendlish adsorption isotherm.

α-Amylase from Thermoactinomyces vulgaris was highly purified 48.9-fold by ammonium sulfate precipitation, gel filtration on Sephadex G-50 column, and ion exchange chromatography column of DEAE-cellulose. The molecular weight of the enzyme was estimated to be 135 and 145 kDa by SDS-PAGE. Its high molecular weight is due to high glycosylation. The purified amylase exhibited maximal activity at pH 6.0 to 7.0 and was stable in the range of pH 4.0 to 9.0. The optimum temperature for its activity was 50 °C. The enzyme half-life time was 120 min at 50 °C, suggesting intermediate temperature stable α-amylase. The enzyme was sensitive to different metal ions, including NaCl, CoCl(2), and CaCl(2), and to different concentrations of EDTA. The enzyme activity was inhibited in the presence of 1 mM CaCl(2), suggesting that it is a calcium-independent α-amylase. The TLC showed that the amylase hydrolyzed starch to produce large maltooligosaccharides as the main products. A 1.1-kb DNA fragment of the putative α-amylase gene (amy TVE) from T. vulgaris was amplified by using two specific newly designed primers. Sequencing analysis showed 56.2 % similarity to other Thermoactinomyces α-amylases with two conserved active sites confirming its function.

A novel series of copper(II) and palladium(II) with 4-derivatives benzaldehyde pyrazolone (L(n)) were synthesized. The mixed ligand complexes were prepared by using 1,10-phenanthroline (Phen) as second ligand. The structure of these complexes was identified and confirm by elemental analysis, molar conductivity, UV-Vis, IR and (1)H NMR spectroscopy and magnetic moment measurements as well as thermal analysis. The ligand behaves as a neutral bidentate ligand through ON donor sites. ESR spectra show the simultaneous presence of a planar trans and a nearly planar cis isomers in the 1:2 ratio for all N,O complexes [Cu(L(n))(2)]Cl(2)⋅2H(2)O. Schiff bases (L(n)) were tested against bacterial species; namely two Gram positive bacteria (Staphylococcus aureus and Bacillus cereus) and two Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae) and fungal species (Aspergillus niger, Fusarium oxysporium, Penicillium italicum and Alternaria alternata). The tested compounds have antibacterial activity against S. aureus, B. cereus and K. pneumoniae.

Thirty nine isolates of Escherichia coli, twenty two isolates of Klebsiella pneumoniae and sixteen isolates of Pseudomonas aeruginosa isolated from urinary tract infected patients were analyzed by antimicrobial susceptibility typing and random amplified polymorphic DNA (RAPD)-PCR. Antibiotic susceptibility testing was carried out by microdilution and E Test methods. From the antibiotic susceptibility, ten patterns were recorded (four for E. coli, three for K. pneumoniae and three for P. aeruginosa respectively). Furthermore, genotyping showed seventeen RAPD patterns (seven for E. coli, five for K. pneumoniae and five for P. aeruginosa respectively). In this study, differentiation of strains of E. coli, K. pneumoniae and P. aeruginosa from nosocomial infection was possible with the use of RAPD.

The identification of native HCV antigens may prove very useful in the diagnosis and early treatment of HCV infection. Here, we aimed to identify and partially characterize a native HCV-NS4 antigen.The western blot, ELISA and immunohistochemical staining were used to identify the native antigen in sera and liver biopsies of HCV serotype 4 infected patients.The native NS4 antigen was identified in serum at 27-kDa molecular weight, in addition to a lower approximately 21-kDa antigen. The purified HCV antigen showed a polypeptide band at 27-kDa when analyzed by silver stained SDS-PAGE and a single peak at 7.6 min by capillary zone electrophoresis. The immunostaining pattern of hepatocytes was cytoplasmic with mainly coarse granular and diffuse pattern based on specific rabbit antisera to the native HCV antigen. A highly significant correlation (r=0.797, p0.0001) was shown between serum concentrations of the HCV-NS4 antigen and HCV-RNA. Also, antigen detection rates were increased (p0.05) with the progression of liver disease.A native HCV-NS4 antigen was identified and partially characterized as 27-kDa protein and the NS4 antigenemia based ELISA test can serve as a useful addition to HCV diagnostic methods, especially under field condition.

Lake Manzala in Egypt have shown great changes in water properties including pH (7.4 to 8.4), total suspended solids (19 to 350 mg/l), total dissolved salts (1578 to 33480 mg/l), dissolved oxygen (2.25 to 8.45 mg/l), ammonia (0.00 to 44.8 mg/l) and nitrate (0.00 to 8.96 mg/l). In addition there has been quite high bacterial density in water and fish of the lake, including total viable bacterial counts and indicator organisms such as total coliforms, faecal coliforms and some other organisms such as Aeromonas spp., Vibrio spp. and Staphylococcus spp. However, the magnitude number of bacteria in water and fish was found to vary sometimes considerably and sometimes slightly depending on the site of sampling. Our results herein showed that LakeManzala is highly contaminated.

α-Amylase (AmyLa) from Laceyella sp. DS3 was purified 13.8 fold by ammonium sulfate precipitation, gel filtration and ion exchange chromatography. The purified AmyLa showed an optimum pH of 7 and an optimum temperature 55°C. It had activation energy, Km and Vmax of 196.1 K joules, 0.81 mg/mL and 2.85 mg/min, respectively. Co2+, Cu2+, Hg2+ and Na+ were strong inhibitors of AmyLa whereas Cl- was an activator. Although AmyLa is a Ca2+ independent α-amylase, it was activated by Ca2+. The AmyLa gene encoding α-amylase activity was sequenced. It revealed putative triple promoters and an open reading frame of 1449 bp (483 amino acids) including a 29 amino acid putative signal peptide. AmyLa was shown to possess four conserved sequence regions of the GH13 family. Polyacrylamide gel electrophoresis identified 69.2 and 72.5 kDa proteins whose α-amylase activities were confirmed by native gel staining. Modelling of AmyLa revealed three domains A-C with domain A containing a catalytic (β/α)8 barrel. Phylogenetic and evolutionary tree analysis suggests that AmyLa might be have been transferred from fungi to an ancient thermoactinomycete ancestor, then adapted to bacterial genome features.

A series of copper (II) complexes of bidentate azo rhodanine ligands (HLn) have been synthesized and characterized. The IR spectral and thermogravimetric analysis are used to characterize the isolated complexes. X-ray diffraction patterns show polycrystalline nature for as-synthesized ligand HL2 and its complex. Quantum chemical parameters, absolute hardness, global electrophilicity and additional electronic charge were calculated for HLn. Copper(II) complexes (1-4) are tested against four local bacterial species; namely two Gram positive bacteria (Staphylococcus aureus and Bacillus cereus) and two Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae) and against four local fungal species (Aspergillus niger, Fusarium oxysporium, Penicillium italicum and Alternaria alternata). The tested complexes have good antibacterial activity against Staphylococcus aureus and Escherichia coli and have low antifungal activity against Aspergillus niger, Fusarium oxysporium and Alternaria alternata. We found that the complex (3) is more active than other complexes against Staphylococcus aureus and Escherichia coli as expected from Hammett’s substituent coefficients (σR). Ultrastructure studies of the affected Staphylococcus aureus and Escherichia coli confirmed that complex (3) has bactericidal effect.