Evidence for proliferation of Enterobacter cloacae on carbohydrates in cucumber and pea spermosphere

1992 ◽  
Vol 38 (11) ◽  
pp. 1128-1134 ◽  
Author(s):  
Daniel P. Roberts ◽  
Carol J. Sheets ◽  
John S. Hartung
Keyword(s):  
Seed Storage ◽  
Enterobacter Cloacae ◽  
Resistant Mutant ◽  
Loamy Sand Soil ◽  
Key Words Carbohydrate ◽  
Proliferation Assays ◽  
Pea Seed ◽  
Seed Extracts ◽  
Storage Carbohydrates

Enterobacter cloacae EcCT501 grew on a variety of mono- and oligo-saccharides in vitro but did not grow on any of the polysaccharides tested. Carbohydrates found in seed exudates supported growth as did major monosaccharide constituents of seed storage carbohydrates and various seed-associated oligosaccharides. In addition, a rifampicin-resistant mutant of E. cloacae EcCT501, strain 501R3, grew on several of these mono- and oligo-saccharides in a natural gravely loamy sand soil. Glycosidase activities were detected in E. cloacae EcCT501 cultures that have the potential to degrade carbohydrate seed exudates and the oligosaccharide components of seed storage carbohydrates. Aqueous extracts from corn and pea seed induced activities of α-galactosidase 15- and 18-fold, respectively. Activities of α-glucosidase, β-glucosidase, and β-xylosidase were slightly induced by corn and pea seed extracts. Induction of these glycosidase activities by these extracts is consistent with their involvement in spermosphere proliferation. No carbohydrate depolymerase activities were detected. Strain A-11, which was isolated after mutation of strain 501R3 with transposon mini-Tn5 Km, lost the ability to grow on or had a reduced growth rate on several carbohydrates. Strain A-11 was similar to strain 501R3 in other nutritional tests. In cucumber spermosphere proliferation assays populations of strains 501R3 and A-11 were significantly different (P = 0.001) at 20 and 45 h. Strain A-11 did not proliferate in cucumber spermosphere, while strain 501R3 increased in number 21-fold after 45 h. In pea spermosphere, populations of strains A-11 and 501R3 increased 345- and 690-fold, respectively, after 45 h (significantly different at P = 0.1). These data are consistent with the hypothesis that spermosphere mono- and oligo-saccharides have roles as nutrients during spermosphere proliferation by E. cloacae. Key words: carbohydrate nutrition, spermosphere proliferation, glycosidase.

scholarly journals Efficacies of Imipenem, Meropenem, Cefepime, and Ceftazidime in Rats with Experimental Pneumonia Due to a Carbapenem-Hydrolyzing β-Lactamase-Producing Strain of Enterobacter cloacae

2000 ◽  
Vol 44 (4) ◽  
pp. 885-890 ◽  
Author(s):  
Olivier Mimoz ◽  
Sophie Leotard ◽  
Anne Jacolot ◽  
Christophe Padoin ◽  
Kamel Louchahi ◽  
...  
Keyword(s):  
Body Weight ◽  
Renal Impairment ◽  
Uranyl Nitrate ◽  
Enterobacter Cloacae ◽  
Resistant Mutant ◽  
Antibacterial Activities ◽  
Pharmacokinetic Parameters ◽  
Human Pharmacokinetic ◽  
Time Animal

ABSTRACT The antibacterial activities of imipenem-cilastatin, meropenem-cilastatin, cefepime and ceftazidime againstEnterobacter cloacae NOR-1, which produces the carbapenem-hydrolyzing β-lactamase NmcA and a cephalosporinase, and against one of its in vitro-obtained ceftazidime-resistant mutant were compared by using an experimental model of pneumonia with immunocompetent rats. The MICs of the β-lactams with an inoculum of 5 log10 CFU/ml were as follows for E. cloacae NOR-1 and its ceftazidime-resistant mutant, respectively: imipenem, 16 and 128 μg/ml, meropenem, 4 and 32 μg/ml, cefepime, <0.03 and 1 μg/ml, and ceftazidime, 1 and 512 μg/ml. The chromosomally located cephalosporinase and carbapenem-hydrolyzing β-lactamase NmcA were inducible by cefoxitin and meropenem inE. cloacae NOR-1, and both were stably overproduced in the ceftazidime-resistant mutant. Renal impairment was induced (uranyl nitrate, 1 mg/kg of body weight) in rats to simulate the human pharmacokinetic parameters for the β-lactams studied. Animals were intratracheally inoculated with 8.5 log10 CFU of E. cloacae, and therapy was initiated 3 h later. At that time, animal lungs showed bilateral pneumonia containing more than 6 log10 CFU of E. cloacae per g of tissue. Despite the relative low MIC of meropenem for E. cloacae NOR-1, the carbapenem-treated rats had no decrease in bacterial counts in their lungs 60 h after therapy onset compared to the counts for the controls, regardless of whether E. cloacae NOR-1 or its ceftazidime-resistant mutant was inoculated. A significant decrease in bacterial titers was observed for the ceftazidime-treated rats infected with E. cloacae NOR-1 only. Cefepime was the only β-lactam tested effective as treatment against infections due to E. cloacae NOR-1 or its ceftazidime-resistant mutant.

scholarly journals Methods for Pigeon Pea Seed Storage in Puerto Rico

1969 ◽  
pp. 423-427
Author(s):  
M. A. Ellis ◽  
E. J. Ravalo ◽  
R. S. Smith
Keyword(s):  
Seed Germination ◽  
Cold Storage ◽  
Seed Storage ◽  
Pigeon Pea ◽  
Percentage Germination ◽  
Ambient Conditions ◽  
Plastic Bags ◽  
Pea Seeds ◽  
Pea Seed

Pigeon pea seeds were adjusted to 9, 13, and 17% moisture, then placed in cloth bags or air tight plastic bags. Seeds at each of the above mentioned moisture levels and container types were stored both under ambient conditions at Mayagüez and in cold storage (13° C) at Lajas. After 12-month storage, all treatments in cold storage ranged in percentage seed germination in vitro, emergence in sand, and emergence in the field from 90-92%, 88-92% and 70-72%, respectively. All treatments stored in cloth bags under ambient conditions for 12 months had a percentage seed germination in vitro, emergence in sand, and emergence in the field ranging from 36-37%, 32-24% and 16-17%, respectively. There were no significant differences in percentage germination in vitro or in sand or field emergence between seeds stored under ambient conditions at 9 and 13% moisture in plastic bags and seeds stored in cold storage. All seeds stored at 17% moisture in plastic bags were dead after 10 months storage under ambient conditions.

Enterobacter cloacae inhibits human rotavirus infectivity in vitro

2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Mohamed NF Shaheen ◽  
Neveen M Rizk ◽  
Abdou K Allayeh ◽  
Samy M Abdelhamid ◽  
Elmahdy ME Ibrahim
Keyword(s):  
Enterobacter Cloacae ◽  
Human Rotavirus

scholarly journals In VitroAntibacterial Activity of NB-003 against Propionibacterium acnes

2011 ◽  
Vol 55 (9) ◽  
pp. 4211-4217 ◽  
Author(s):  
J. Pannu ◽  
A. McCarthy ◽  
A. Martin ◽  
T. Hamouda ◽  
S. Ciotti ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Propionibacterium Acnes ◽  
Resistant Mutant ◽  
Microtiter Plate ◽  
Content Type ◽  
Oil In Water ◽  
Complete Disruption ◽  
Kinetics Of ◽  
Gel Formulations

ABSTRACTNB-003 and NB-003 gel formulations are oil-in-water nanoemulsions designed for use in bacterial infections.In vitrosusceptibility ofPropionibacterium acnesto NB-003 formulations and comparator drugs was evaluated. Both NB-003 formulations were bactericidal against allP. acnesisolates, including those that were erythromycin, clindamycin, and/or tetracycline resistant. In the absence of sebum, the MIC90s/minimum bactericidal concentrations (MBC90s) for NB-003, NB-003 gel, salicylic acid (SA), and benzoyl peroxide (BPO) were 0.5/2.0, 1.0/2.0, 1,000/2,000, and 50/200 μg/ml, respectively. In the presence of 50% sebum, the MIC90s/MBC90s of NB003 and BPOs increased to 128/1,024 and 400/1,600 μg/ml, respectively. The MIC90s/MBC90s of SA were not significantly impacted by the presence of sebum. A reduction in the MBC90s for NB-003 and BPO was observed when 2% SA or 0.5% BPO was integrated into the formulation, resulting in MIC90s/MBC90s of 128/256 μg/ml for NB003 and 214/428 μg/ml for BPO. The addition of EDTA enhanced thein vitroefficacy of 0.5% NB-003 in the presence or absence of 25% sebum. The addition of 5 mM EDTA to each well of the microtiter plate resulted in a >16- and >256-fold decrease in MIC90and MBC90, yielding a more potent MIC90/MBC90of ≤1/<1 μg/ml. The kinetics of bactericidal activity of NB-003 againstP. acneswere compared to those of a commercially available product of BPO. Electron micrographs ofP. acnestreated with NB-003 showed complete disruption of bacteria. Assessment of spontaneous resistance ofP. acnesrevealed no stably resistant mutant strains.

scholarly journals Activity of Ceftazidime-Avibactam against Fluoroquinolone-Resistant Enterobacteriaceae and Pseudomonas aeruginosa

2015 ◽  
Vol 59 (6) ◽  
pp. 3059-3065 ◽  
Author(s):  
C. Pitart ◽  
F. Marco ◽  
T. A. Keating ◽  
W. W. Nichols ◽  
J. Vila
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Resistant Mutant ◽  
Fluoroquinolone Resistance ◽  
Cross Resistance ◽  
Content Type ◽  
E Coli ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
The Impact

ABSTRACTCeftazidime-avibactam and comparator antibiotics were tested by the broth microdilution method against 200Enterobacteriaceaeand 25Pseudomonas aeruginosastrains resistant to fluoroquinolones (including strains with the extended-spectrum β-lactamase [ESBL] phenotype and ceftazidime-resistant strains) collected from our institution. The MICs and mechanisms of resistance to fluoroquinolone were also studied. Ninety-nine percent of fluoroquinolone-resistantEnterobacteriaceaestrains were inhibited at a ceftazidime-avibactam MIC of ≤4 mg/liter (using the susceptible CLSI breakpoint for ceftazidime alone as a reference). Ceftazidime-avibactam was very active against ESBLEscherichia coli(MIC90of 0.25 mg/liter), ESBLKlebsiella pneumoniae(MIC90of 0.5 mg/liter), ceftazidime-resistant AmpC-producing species (MIC90of 1 mg/liter), non-ESBLE. coli(MIC90of ≤0.125 mg/liter), non-ESBLK. pneumoniae(MIC90of 0.25 mg/liter), and ceftazidime-nonresistant AmpC-producing species (MIC90of ≤0.5 mg/liter). Ninety-six percent of fluoroquinolone-resistantP. aeruginosastrains were inhibited at a ceftazidime-avibactam MIC of ≤8 mg/liter (using the susceptible CLSI breakpoint for ceftazidime alone as a reference), with a MIC90of 8 mg/liter. Additionally, fluoroquinolone-resistant mutants from each species tested were obtainedin vitrofrom two strains, one susceptible to ceftazidime and the other a β-lactamase producer with a high MIC against ceftazidime but susceptible to ceftazidime-avibactam. Thereby, the impact of fluoroquinolone resistance on the activity of ceftazidime-avibactam could be assessed. The MIC90values of ceftazidime-avibactam for the fluoroquinolone-resistant mutant strains ofEnterobacteriaceaeandP. aeruginosawere ≤4 mg/liter and ≤8 mg/liter, respectively. We conclude that the presence of fluoroquinolone resistance does not affectEnterobacteriaceaeandP. aeruginosasusceptibility to ceftazidime-avibactam; that is, there is no cross-resistance.

scholarly journals Enterobacteriaceae isolates carrying the New Delhi metallo-β-lactamase gene in Yemen

2014 ◽  
Vol 63 (10) ◽  
pp. 1316-1323 ◽  
Author(s):  
Alima Gharout-Sait ◽  
Samer-Ahmed Alsharapy ◽  
Lucien Brasme ◽  
Abdelaziz Touati ◽  
Rachida Kermas ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Susceptibility Testing ◽  
Enterobacter Cloacae ◽  
New Delhi ◽  
Carbapenem Resistant ◽  
Genes Encoding ◽  
Phenotypic Tests ◽  
Lactamase Gene ◽  
Sequence Types

Ten carbapenem-resistant Enterobacteriaceae (eight Klebsiella pneumoniae isolates and two Enterobacter cloacae) isolates from Yemen were investigated using in vitro antimicrobial susceptibility testing, phenotypic carbapenemase detection, multilocus sequence typing (MLST) and replicon typing. Carbapenemase, extended-spectrum β-lactamase (ESBL) and plasmid-mediated quinolone resistance determinant genes were identified using PCR and sequencing. All of the 10 carbapenem-resistant Enterobacteriaceae were resistant to β-lactams, tobramycin, ciprofloxacin and cotrimoxazole. Imipenem, doripenem and meropenem MICs ranged from 2 to >32 mg l−1 and ertapenem MICs ranged from 6 to >32 mg l−1. All of the K. pneumoniae isolates showed ESBL activity in phenotypic tests. Genes encoding bla NDM were detected in all strains. All K. pneumoniae strains produced CTX-M-15 ESBL and SHV β-lactamases. TEM-1 β-lactamase was detected in seven isolates. Nine isolates were qnr positive including QnrB1, QnrA1 and QnrS1, and six isolates produced AAC-6′-Ib-cr. MLST identified five different sequence types (STs): ST1399, ST147, ST29, ST405 and ST340. Replicon typing showed the presence of IncFII1K plasmids in four transformants. To the best of our knowledge, this is the first report of NDM-1-producing Enterobacteriaceae isolates in Yemen.

scholarly journals Screening of some Leguminosae seeds for nematicidal activity

2004 ◽  
Vol 22 (1) ◽  
pp. 51 ◽  
Author(s):  
Uma R Khurma ◽  
Anupama Mangotra
Keyword(s):  
Seed Extract ◽  
Sesbania Sesban ◽  
Nematode Control ◽  
Recent Past ◽  
Cassia Fistula ◽  
Pongamia Glabra ◽  
Meloidogyne Spp ◽  
Alternative Sources ◽  
Seed Extracts

Root-knot nematodes, Meloidogyne spp., are the major nematode pests of economic crops worldwide. Use of conventional nematicides has been one of the most effective methods to reduce their populations. However, the ban on many effective nematicides in recent past has necessitated the search for alternative sources of effective and ecofriendly chemicals for nematode control. The nematicidal potential of fifteen Leguminosae seeds (wild and cultivated) was assessed, in vitro, against juveniles of Meloidogyne incognita (Kofoid & White) Chitwood. Each standard aqueous seed extract, 25g/100ml (w/v), was evaluated at dilutions, 1:10, 1:20, and 1:40 at 27+1�C for 24 hours. The majority of seed extracts caused high mortality rates, especially in 1:10 concentration. Trigonella foenum graceum, Sesbania sesban, Albizzia lebbak, Cassia fistula and Pongamia glabra were the most efficacious (above 90% mortality). S. sesban and P. glabra were significantly effective even in the lowest concentration (1:40).

scholarly journals Study of the antiproliferative potential of seed extracts from Northeastern Brazilian plants

2011 ◽  
Vol 83 (3) ◽  
pp. 1045-1058 ◽  
Author(s):  
Paulo Michel P. Ferreira ◽  
Davi F. Farias ◽  
Martônio P. Viana ◽  
Terezinha M. Souza ◽  
Ilka M. Vasconcelos ◽  
...  
Keyword(s):  
Human Cancer ◽  
Ethanolic Extract ◽  
Cell Number ◽  
Northeastern Brazil ◽  
Human Cancer Cells ◽  
Ic50 Value ◽  
Underlying Mechanisms ◽  
Apoptotic Pathways ◽  
Seed Extracts

This study assessed the antiproliferative and cytotoxic potential against tumor lines of ethanolic seed extracts of 21 plant species belonging to different families from Northeastern Brazil. In addition, some underlying mechanisms involved in this cytotoxicity were also investigated. Among the 21 extracts tested, the MTT assay after 72 h of incubation demonstrated that only the ethanolic extract obtained from Myracrodruon urundeuva seeds (EEMUS), which has steroids, alkaloids and phenols, showed in vitro cytotoxic activity against human cancer cells, being 2-fold more active on leukemia HL-60 line [IC50 value of 12.5 (9.5-16.7) μg/mL] than on glioblastoma SF-295 [IC50 of 25.1 (17.3-36.3) μg/mL] and Sarcoma 180 cells [IC50 of 38.1 (33.5-43.4) μg/mL]. After 72h exposure, flow cytometric and morphological analyses of HL-60-treated cells showed that EEMUS caused decrease in cell number, volume and viability as well as internucleosomal DNA fragmentation in a dose-dependent way, suggesting that the EEMUS triggers apoptotic pathways of cell death.

scholarly journals EVALUATION OF IN VITRO ANTI-INFLAMMATORY AND ANTIMICROBIAL ACTIVITY OF AQUEOUS AND METHANOLIC SEED EXTRACTS OF CITRULLUS LANATUS

2017 ◽  
Vol 9 (5) ◽  
pp. 29
Author(s):  
Iswariya S. ◽  
Uma T. S.
Keyword(s):  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Aqueous Extract ◽  
Seed Extract ◽  
Inflammatory Activity ◽  
Diffusion Method ◽  
Klebsiella Pneumonia ◽  
Anti Inflammatory ◽  
Seed Extracts

Objective: The present study was designed to identify the bioactive phytochemicals and its antibacterial and in vitro anti-inflammatory potential of aqueous and methanolic seed extract of Citrullus lanatus.Methods: The phytochemical screening of both the aqueous and methanolic seed extract was carried out qualitatively to identify the major Phyto-constituents present in the extracts. The antimicrobial activity of the extracts was evaluated against six pathogenic bacterial strains by agar well diffusion method and the Minimum inhibitory concentration (MIC) was determined by broth dilution method. In vitro anti-inflammatory activity of C. lanatus seed extracts was evaluated by using human red blood cell (HRBC) membrane stabilization and inhibition of albumin denaturation method.Results: The results of the study indicated that both the extracts of the seed having antimicrobial activity, while the methanolic extract showed more significant activity against the tested organism than aqueous extract. Methanol extract had the lowest MIC of 1.562 mg/ml against Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa and Bacillus subtilis, whereas in aqueous extract was highly sensitive to Bacillus subtilis, E. coli and Klebsiella pneumonia with MIC of 3.125 and 6.25 mg/ml, respectively. Methanolic extracts exerted comparative higher anti-inflammatory activity than aqueous extract.Conclusion: Present study provides a firm evidence to support that the synergistic effect of C. lanatus seed extracts having potent anti-inflammatory and antimicrobial property, which might serve as an effective drug for various microbial infections and inflammatory disorders.

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