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A total of 17 actinomycetes were isolated and screened against five bacterial pathogens. Forty-one per cent of the isolates were active against the tested pathogens. The most potent isolate was identified as Streptomyces parvus by using a 16S rRNA sequence analysis. S. parvus produced active compound(s) against a number of Gram negative and Gram positive bacteria. The obtained inhibition zones were 14, 19, 20 and 20 mm against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Aeromonas hydrophila, respectively. Moreover, the anticancer activity of S. parvus was tested against four different cell lines: human liver cancer cell line, mouse lymphoma cell line, breast cancer cell line and human colon cancer cell line. The inhibition activities were 53%, 56%, 57% and 42%, respectively. To achieve a maximum production of the bioactive compound, PlackettÀBurman design was applied. The productivity increased up to 1.3-fold, when S. parvus was grown in optimized medium composed of: 10 g, 2 mL (10 3 colony-forming units mL ¡1 ) inoculum size with pH 8 for 7 d of incubation. The main constitutes of S. parvus crude extract were determined by gasÀliquid chromatography mass spectrometry. They were found to be ethane, 1,1-diethoxy; di-n-octyl phthalate; ethanol, 2,2-diethoxy; 9,12-octadecadienoic acid; methyl ester (E,E) and benzoic acid.

Ten sediment samples were gathered from several geographical locations around mangrove habitat, Red Sea coast, Egypt, during summer 2019. Actinobacteria are widespread in most mangrove soil samples. The average actinomycetes counts in sediment samples were ranged from 4 to 15 CFUg-1, also physico-chemical characters for soil samples were determined. Statistical analysis was applied to assess if the geographical location and physico-chemical characters influenced the communities of actinomycetes. A total of 10 actinomycetes were isolated and characterized physiologically and biochemically. The antimicrobial activities of different actinomycetes isolates were assessed. Isolate M3 was chosen as the most promising isolate with broad antagonistic activity against Bacillus subtilis ATCC 6633, Escherichia coli ATCC 19404, Staphylococcus aureus ATCC6538, Pseudomonas aeruginosa ATCC 9027, and Candida albicans ATCC 10231 with inhibition zones ranged from 12.0 ± 0.9 to 20.0 ± 1.9 mm. Genotypic characterization of isolate M3 was made using 16S rDNA sequence analysis and identified as Streptomyces mutabilis M3 with accession number MT483919. This strain exhibited anticancer activity against breast cancer cell line (Mcf7), liver cancer cell line (HepG2) and colon cancer cell line (HCT116) and the IC50 values were 324.77, 333.71 and 354.46, respectively. Streptomyces mutabilis M3 MT483919 had high bio-flocculating activity for seawater treatment, and the recovery of the samples ranged between 71.97 and 76.05%. The crude extract of Streptomyces mutabilis MT483919 M3 was analyzed by Fourier transform infrared spectrum (FT-IR) and Gas chromatography-mass spectrometry (GC-MS).

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Background The utilization of bioluminescent bacteria in environmental monitoring of water contaminates considers being a vital and powerful approach. This study aimed to isolate, optimize, and apply luminescent bacteria for toxicity monitoring of various toxicants in wastewater. Results On the basis of light intensity, strain Vibrio sp. 6HFE was initially selected, physiologically/morphologically characterized, and identified using the 16SrDNA gene. The luminescence production was further optimized by employing statistical approaches (Plackett-Burman design and central composite design). The maximum bioluminescence intensity recorded 1.53 × 106 CPS using optimized medium containing (g/L), yeast extract (0.2g), CaCl2 (4.0), MgSO4 (0.1), and K2HPO4 (0.1) by 2.3-fold increase within 1h. The harnessing of Vibrio sp. 6HFE as a bioluminescent reporter for toxicity of organic solvents was examined using a bioluminescence inhibition assay. According to IC50 results, the toxicity order of such pollutants was chloroform > isoamyl > acetic acid > formamide > ethyl acetate > acetonitrile > DMSO > acetone > methanol. However, among eight heavy metals tested, the bioluminescence was most sensitive to Ag+ and Hg+ and least sensitive to Co2+ and Ni2+. Additionally, the bioluminescence was inhibited by benzene, catechol, phenol, and penta-chlorophenol at 443.1, 500, 535.1, and 537.4 ppm. Conclusion Vibrio sp. 6HFE succeeded in pollution detection at four different environmental and wastewater samples revealing its efficiency in ecotoxicity monitoring.

Achrom mode ba Hana National Sediments used as a g North Delta from 9.8x10 Delta sedim selected th 4% (w/v) a identified a analysis. Th and NaCl respectively showed no only by V. p 014 and V. both strains 89.982 mmo tolerance to

Mediterranean Sea Genotype heavy metals azo-dyes Fourteen psychrotolerant Pseudomonas strains were isolated from seawater and sediments in the Mediterranean Sea, Egypt, using culturedependent techniques. Genotypic characterization for the fourteen strains was performed using 16S rDNA sequence analysis. The Pseudomonas strains were screened for some physiological, and biochemical characters, also resistance to some antibiotics and heavy metals were tested. Moreover, heavy metals bioaccumulation and azo-dyes removal were estimated. All tested Pseudomonas strains were able to resist and accumulate several metals (Pb 2 +, Cu 2+ and Cd 2+) with variable degrees, depending on bacterial strains and metal ion species. The highest tolerance (MICs) was observed with lead ions as all strains grew in presence of 750-800 ppm of lead, also, lead ions were easier to be bioaccumulate than the other metals, while cadmium bioaccumulation was relatively low with respect to the other two metals. Pseudomonas sp. H69A was the most potent strain in accumulation of the different metals. It supports the highest accumulated values of lead and cupper (2.95 and 1.837 mg /g fresh cells, respectively).The Pseudomonas strains were monitored for their ability to decolorize three different azo-dyes (fast orange, methanil yellow and acid fast red). All Pseudomonas strains achieved powerfull decolorization activity with the tested dyes. The maximum decolorization activities were recorded in fast orange. Pseudmonas sp. H26S recorded the highest decolorization percentages (91%) with fast orange and their biosorption capacity was 4.8 mg/g.

Antimicrobial resistance is a main public health problem that can possibly cause an expected 10 million mortalities per year by 2050 (Sugden et al., 2016). The crisis of antimicrobial resistance has been attributed to the absence of new agents or misuse of ARTICLE INFO