eng
National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology
Egyptian Journal of Microbiology
0022-2704
2357-0881
2013-12-31
48
1
1
21
10.21608/ejm.2013.245
245
Original Article
Removal of Lead(II) by Saccharomyces cerevisiae AUMC 3875
THE REMOVAL of lead(II) from artificial aqueous solution using live and dead biomass of Saccharomyces cerevisiae AUMC 3875 was investigated. The minimum inhibitory concentration (MIC) value of S. cerevisiae AUMC 3875 for lead(II) was 600mg/l. Maximum lead(II) uptake capacities were achieved at pH 5.0 and initial metal ion concentration 300mg/l using 3g/l live and dead cells, respectively. Maximum biosorption capacities were reached after 3h and 20min for live and dead cells, respectively. Fourier Transform Infrared spectroscopy (FTIR) results revealed the important role of C=O, ـــ OH, ـــ NH, protein amide II band, 2 PO , mannans, sulphur and sulphur-oxygen compounds in lead(II) uptake. Scanning electron microscopy analysis (SEM) showed that the cell surface morphology and surface area/volume ratio changed greatly after lead(II) uptake. Transmission electron microscopy analysis (TEM) confirmed the involvement of both extracellular adsorption and intracellular penetration through the cell wall. X-ray powder diffraction (XRD) analysis revealed the presence of Pb(SO4), Pb2OSO4 in dead yeast cells and Pb3O2(SO4),Pb2OSO4 in live biomass. Energy dispersive Xray microanalysis (EDAX) confirmed the occurrence of sulphur, oxygen and lead(II) on the cell wall. The removal of lead(II) from storage battery industry wastewater was performed by dead yeast cells efficiently.
https://ejm.journals.ekb.eg/article_245_74d82e41f77477908ce0a92b24fc79b9.pdf
Saccharomyces cerevisiae
> Lead(II)
Biosorption
SEM
TEM
FTIR
EDAX
XRD
eng
National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology
Egyptian Journal of Microbiology
0022-2704
2357-0881
2013-12-31
48
1
23
52
10.21608/ejm.2013.246
246
Original Article
An Investigation on Tolerance and Biosorption Potential of Aspergillus awamori ZU JQ 965830.1 to Cu(II)
THE MINIMUM inhibitory concentration (MIC) value of A.awamori for Cu(II) was 3100mg/l and a complete inhibition of biomass production was observed at 800mg/l concentration of Cu(II). Slight changes were observed by SEM investigation in Cu(II)-stressed biomass. Quantification of Cu(II) was performed by EDAX. Transmission electron microscopy investigation (TEM) confirmed the involvement of extracellular adsorption, intracellular penetration through the cell wall and vacuolation. Cu(II) stress induced noticeable changes in the activities of polyphenol oxidase(PPO), glutathione reductase (GR) and peroxidase (POD) and in the concentration of total antioxidant, soluble protein and thiol. High performance liquid chromatography analysis (HPLC) revealed that Cu(II) stress stimulated the production of oxalic acid .Maximum Cu(II) uptake capacity was achieved at pH 4.0, initial metal ion concentration 500mg/l and biomass dosage 1g/l. Maximum Cu(II) uptake capacities were reached after 180 min for live biomass and 30 min for dead biomass. Fourier transform infrared spectroscopy (FTIR) results gave an indication of chelation between oxygen-, nitrogen-, phosphorus- and especially sulphur-containing ligands of biomass with metal ions. X-ray diffraction analysis (XRD) revealed the presence of CuSO4.H2O in live and dead biomass. EDAX confirmed the occurrence of sulphur, oxygen and Cu(II) in the cell wall
https://ejm.journals.ekb.eg/article_246_169743234d48643ca7e2fea5ed762ee5.pdf
Aspergillus awamor
Cu(II)
Stress
Antioxidant enzymes
Biosorption
eng
National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology
Egyptian Journal of Microbiology
0022-2704
2357-0881
2013-12-31
48
1
53
69
10.21608/ejm.2013.247
247
Original Article
Use of Different Antibiotic Combinations against Fluoroquinolone-Resistant Salmonella enterica from Humans in Egypt
EMERGENCE of antibiotic resistance by pathogenic Salmonella spp. is a worldwide problem. Antibiotic combination was used as a clinical cure to solve the problem. Over one and a half years , one hundred gastroenteritis bacterial pathogens were collected from three Egyptian hospitals from fecal and blood sources. 58% Salmonella isolates were purified and identified using phenotyping and serotyping techniques. Out of the 58% Salmonella spp., 41.4% represented S. Typhimurium, 27.6% S. Enteritidis, 5.2% S. Typhi, 3.4 % S. ParatyphiA, 3.4 % S. Paratyphi B and 19.0% other Salmonella. A total of 36 (62%) out of 58 Salmonella spp. were fluroquinolone resistant by disk diffusion method. Resistance of five Salmonella strains to the fluroquinolone group was confirmed by MICs values. The level of these values was from 32 - >512 µg/ml, which is higher than those recommended by CLSI. Seventy-five combined microtitre checkerboards were performed on the five fluroquinolone multiresistant Salmonella strains to assess the potential for combination therapy. No antagonism was observed with any combination. Synergy and additivity were achieved with 41.4% and 58.6%, respectively. Time-kill synergy was more often seen at 24hr. There is 100%, 50% and 40% agreement between time-kill and checkerboard results for three Salmonella strains. Resistant Salmonella has increased in Egypt. Fluroquinolone combination with β-lactams (gentamycin, amikacin) and aminoglycosides (cefotaxime) were effective in the treatment of resistant Salmonella Typhimurium, Enteritidis and Typhi.
https://ejm.journals.ekb.eg/article_247_4884da2bd48e9349a7e6535bdc69954b.pdf
Salmonella enterica
Antibiotic combination
Antibiotic resistance
Fluoroquinolone
eng
National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology
Egyptian Journal of Microbiology
0022-2704
2357-0881
2013-12-31
48
1
71
85
10.21608/ejm.2013.248
248
Original Article
Beneficial Effects of Calcium Chloride on Two Cyanobacterial Species under Sodium Chloride Stress
EXPOSURE of Anabaena constricta and Nostoc linckia to 0.2M NaCl induced a significant decrease in cell number, dry weight and pigments (chlorophyll “a” and carotenoids,). Also, there was a decrease in glucose, protein and nitrogen contents. The addition of two different concentrations of CaCl2 (40 and 60 mM) to the salinized cultures with both organisms induced a significant increase in growth and metabolites activities. Protein electrophoretic patterns of the culture of A. constricta exposed to 0.2 M NaCl showed the disappearance of one protein band at 77 KDa and appearance of two protein bands at 171 and 70 KDa. The addition of 40 mM CaCl2 to the salinized culture of A.constricta showed disappearance of one protein at 77 KDa and appearance of three protein bands at 17, 61 and 162 KDa, while addition of 60 mM CaCl2 to salinized culture caused appearance of three protein bands at 18, 58 and 138 KDa as compared with control (salinized culture of 0.2 M NaCl alone). Addition of 0.2 M NaCl to culture of N.linckia and addition of 40 mM or 60 mM CaCl2 to salinized culture showed no change of protein patterns as compared with control (culture without NaCl) but differed in the percentage of intensity of proteins
https://ejm.journals.ekb.eg/article_248_afdb9b32a6caa345d95363d1b133b6df.pdf
Anabaena sp
Nostoc sp
Cyanobacteria
salinity stress
Protein profile
Mitigate effect of CaCl