Prevalence and Characterization of Bacillus cereus Isolates from Clinical and Natural Sources

1996 ◽  
Vol 59 (2) ◽  
pp. 193-196 ◽  
Author(s):  
GHADA HASSAN ◽  
NASSIM NABBUT
Keyword(s):  
Bacillus Cereus ◽  
Antimicrobial Susceptibility ◽  
Nitrate Reduction ◽  
The Other ◽  
Clinical Isolates ◽  
Natural Sources ◽  
Natural Isolates ◽  
Esculin Hydrolysis ◽  
Biochemical Profiles

Bacillus cereus clinical isolates recovered from blood, wounds and diarrheal feces as well as natural isolates from normal feces, rice, dehydrated milk, and soil were characterized with respect to their biochemical profiles, antimicrobial susceptibility and enterotoxigenicity. The biochemical profiles of all the isolates were similar regardless of their sources. However, some degree of variability was shown in the Voges-Proskauer, nitrate reduction, and esculin hydrolysis tests and in the ability to grow in the presence of 40% bile. All the isolates were resistant to amoxicillin, oxacillin, and penicillin and susceptible to gentamicin and vancomycin. Susceptibility to cephalothin was variable among the clinical isolates, whereas susceptibility to clindamycin and erythromycin was inconsistent for all of them. The B. cereus clinical isolates recovered from human diarrheal feces were found to be strong producers of diarrheal enterotoxin as revealed by induction of diarrhea in mice and vascular permeability reaction. The clinical isolates recovered from wounds and blood and the natural isolates recovered from rice, milk, and normal feces, on the other hand, were weak producers of diarrheal enterotoxin.

Occurrence of Bacillus cereus and the Bacteriological Quality of Chinese “Take-Out” Foods

1978 ◽  
Vol 41 (6) ◽  
pp. 450-454 ◽  
Author(s):  
D. A. SCHIEMANN
Keyword(s):  
Bacillus Cereus ◽  
Nitrate Reduction ◽  
Biochemical Characterization ◽  
Bacteriological Examination ◽  
Bacteriological Quality ◽  
Litmus Milk ◽  
Aerobic And Anaerobic ◽  
Gelatin Hydrolysis

One hundred sixty-five samples of various foods were collected from 24 different Chinese take-out restaurants for bacteriological examination which included enumeration of Bacillus cereus by three media, MYP, KG and blood agars. Blood agar was less selective but no quantitative differences in recovery were apparent. Twenty-eight samples (15%) yielded B. cereus in excess of 100 per gram, and 20 of these were fried rice (33% positive), which also showed the poorest overall bacteriological quality. Biochemical characterization of 232 isolates of B. cereus showed 96% or more positive for catalase, nitrate reduction, beta-haemolysis, subterminal-ellipsoidal spores, aerobic and anaerobic utilization of glucose, Voges-Proskauer, fermentation of glycerol, gelatin hydrolysis, and alkaline peptonization of litmus milk; and a negative reaction in mannitol. Variable results were obtained for motility, fermentation of sucrose and salicin, and starch hydrolysis. Thirty-three isolates were susceptible to 12 of 19 antibiotics tested, and resistant to colistin. Six (18%) were susceptible to penicillin.

Characterization of Bacillus cereus Isolates from Raw Soybean Sprouts

2004 ◽  
Vol 67 (5) ◽  
pp. 1031-1035 ◽  
Author(s):  
HYE-JUNG KIM ◽  
DONG SUN LEE ◽  
HYUN-DONG PAIK
Keyword(s):  
Bacillus Cereus ◽  
Clostridium Perfringens ◽  
Clostridium Botulinum ◽  
The Other ◽  
Starch Hydrolysis ◽  
Anaerobic Microorganisms ◽  
Soybean Sprouts ◽  
Large Populations ◽  
Mesophilic Microorganism

Raw soybean sprouts, which are used as ingredients in cook-chilled products, were analyzed to evaluate the incidence of mesophilic aerobic microorganisms, psychrotrophic microorganisms, anaerobic microorganisms, coliforms, and spore-forming microorganisms Bacillus cereus, Clostridium botulinum, and Clostridium perfringens. Mesophilic microorganisms on raw soybean sprouts were present in large populations, 5.5 × 106 to 1.4 × 108 CFU/g, and psychrotrophic microorganisms were found to be more numerous than the other groups. Coliforms accounted for 15% of mesophilic microorganism counts on average, and the average for spore-forming microorganisms was 5.2 × 102 CFU/g. B. cereus was isolated from 12 of 17 soybean sprout samples, whereas C. botulinum and C. perfringens were not isolated. B. cereus was isolated in greater numbers at 30° C compared with other temperatures and was not isolated at 4° C. Of the 55 strains isolated from soybean sprouts, 52 were positive for starch hydrolysis, and only 3 strains did not hydrolyze starch. Among the 55 strains of B. cereus isolates, 53 showed the ability to produce diarrheal enterotoxin by CRET-RPLA.

scholarly journals Comparative Study of Adsorption Phenomena of Direct Dye Black E by Palm Nut Shell Carbon and Treated Flyash Residue with Respect to Activated Charcoal Carbon

2013 ◽  
Vol 7 ◽  
pp. 80-94
Author(s):  
C. Palanivel ◽  
L.D. Prabhakar ◽  
M. Emayavaramban
Keyword(s):  
Industrial Effluent ◽  
Freundlich Isotherm ◽  
Cost Effective ◽  
The Other ◽  
Colour Removal ◽  
Natural Sources ◽  
Textile Dyeing ◽  
Direct Dye ◽  
Adsorption Phenomena

Many researchers aimed to study the removal of colouring matter from textile dyeing industrial effluent using the carbon derived from natural sources. Because adsorption of the dyes on carbon is easily, cost effective when comparing to the other techniques. Hence we aimed at the preparation and characterization of the carbon from the natural sources like palm nut shell and flyash. These carbons have been used for adsorption of direct dye Black E. The effect of pH, carbon dose and equilibration period were examined along within the Langmuir and Freundlich isotherm studies. The application of these carbons was investigated on adsorption and colour removal from effluent and synthetic samples, which consists of commercial direct dye Black E.

scholarly journals Identification and Characterization of a Novel FosA7 Member from Fosfomycin-Resistant Escherichia coli Clinical Isolates from Canadian Hospitals

2020 ◽  
Vol 65 (1) ◽  
pp. e00865-20
Author(s):  
Kieran A. Milner ◽  
Denice C. Bay ◽  
David Alexander ◽  
Andrew Walkty ◽  
James A. Karlowsky ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Clinical Isolates ◽  
Phenotypic Characterization ◽  
Content Type ◽  
E Coli ◽  
Fosfomycin Resistance ◽  
Identification And Characterization

ABSTRACTHere, we characterize the fosA genes from three Escherichia coli clinical isolates recovered from Canadian patients. Each fosA sequence was individually overexpressed in E. coli BW25113, and antimicrobial susceptibility testing was performed to assess their role in fosfomycin resistance. The findings from this study identify and functionally characterize FosA3, FosA8, and novel FosA7 members and highlight the importance of phenotypic characterization of fosA genes.

scholarly journals Biochemical and Mutational Studies of the Bacillus cereus CECT 5050T Formamidase Support the Existence of a C-E-E-K Tetrad in Several Members of the Nitrilase Superfamily

2011 ◽  
Vol 77 (16) ◽  
pp. 5761-5769 ◽  
Author(s):  
Pablo Soriano-Maldonado ◽  
Ana Isabel Martínez-Gómez ◽  
Montserrat Andújar-Sánchez ◽  
José L. Neira ◽  
Josefa María Clemente-Jiménez ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Sequence Analysis ◽  
Bacillus Cereus ◽  
The Other ◽  
Human Pathogens ◽  
Purification And Characterization ◽  
Content Type ◽  
The One ◽  
Derivatives Of

ABSTRACTFormamidases (EC 3.5.1.49) are poorly characterized proteins. In spite of this scarce knowledge, ammonia has been described as playing a central role in the pathogenesis of human pathogens such asHelicobacter pylori, for which formamidase has been shown to participate in the nitrogen metabolic pathway. Sequence analysis has revealed that at least two different groups of formamidases are classified as EC 3.5.1.49: on the one hand, the derivatives of the FmdA-AmdA superfamily, which are the best studied to date, and on the other hand, the derivatives ofHelicobacter pyloriAmiF. Here we present the cloning, purification, and characterization of a recombinant formamidase fromBacillus cereusCECT 5050T (BceAmiF), the second member of the AmiF subfamily to be characterized, showing new features of the enzyme further supporting its relationship with aliphatic amidases. We also present homology modeling-based mutational studies confirming the importance of the Glu140 and Tyr191 residues in the enzymatic activities of the AmiF family. Moreover, we can conclude that a second glutamate residue is critical in several members of the nitrilase superfamily, meaning that what has consistently been identified as a C-E-K triad is in fact a C-E-E-K tetrad.

scholarly journals Reduction in Glycopeptide Resistance in Vancomycin-Resistant Enterococci as a Result of vanA Cluster Rearrangements

2004 ◽  
Vol 48 (4) ◽  
pp. 1379-1381 ◽  
Author(s):  
Wee Gyo Lee ◽  
Ji Young Huh ◽  
Sung Ran Cho ◽  
Young Ae Lim
Keyword(s):  
Molecular Characterization ◽  
Intergenic Region ◽  
The Other ◽  
Clinical Isolates ◽  
Partial Deletion ◽  
Glycopeptide Resistance ◽  
Reading Frame ◽  
Vancomycin Resistant Enterococci ◽  
Vancomycin Resistant

ABSTRACT The molecular characterization of five clinical isolates of vanA-containing vancomycin-resistant enterococci with altered resistance to glycopeptides was examined. One strain represented an IS1216V insertion accompanied by partial deletion of the reading frame of vanX following a transposition event. The other four strains represented IS1216V within the vanX-vanY intergenic region associated with deletion of vanY or vanZ.

scholarly journals Characterization and Optimization of L-Malic Acid Production by Some Clinical Isolates of Aureobasidium pullulans

2020 ◽  
Vol 8 (4) ◽  
pp. 209-214
Author(s):  
Taha Jafarian-Haris ◽  
◽  
Alireza Tavakkoli ◽  
Mohammad Javad Najafzadeh ◽  
Abolghasem Danesh ◽  
...  
Keyword(s):  
Malic Acid ◽  
Aureobasidium Pullulans ◽  
The Other ◽  
Clinical Isolates ◽  
Aliphatic Polyester ◽  
Natural Sources ◽  
Pharmaceutical Industries ◽  
Fermentation Period ◽  
C 32 ◽  
Incubation Temperatures

Background: Poly-L-malic acid (PLMA) comprises aliphatic polyester polymers with broad applications in pharmaceutical industries. The fungal microorganisms are among the best natural sources recruited to supply L-malic acid (MA) as a precursor of PLMA. In this study, we investigated MA production ability of 7 clinical isolated of the fungus Aureobasidium pullulans. Materials and Methods: Seven clinical isolates of A. pullulans acquired from Westerdijk Fungal Biodiversity Institute were studied, and the isolate with the highest total MA production was selected for the optimization process. We tried to optimize the output by applying different concentrations of CaCO3 in fungus medium (1.5%, 3%, and 6%) and various incubation temperatures (27°C, 32°C, and 37°C) during 3, 7, and 14 days. Results: Intra-strains variation was significantly strong (P<0.0001), and the highest production of MA was carried out by the isolate A. pullulans var. melanigenum dH 21931, UTHSC 06-456. The amount of MA produced by this strain was significantly higher in medium with 3% CaCO3 compared with other concentrations of CaCO3 and after 7 days incubation than the other fermentation times (P<0.05). Although MA production was higher at 27°C, the differences between the investigated various temperatures were not significant (P>0.05). Conclusion: Overall, we obtained the highest MA production in Sabouraud dextrose agar (SDA)medium with 3% CaCO3 at 27°C after 7 days of incubation. Our study indicated that the fermentation period and CaCO3 concentration significantly alter MA production in A. pullulans var. melanigenum.

Sign in / Sign up

Export Citation Format

Share Document