scholarly journals Modification of Sorbitol MacConkey Medium Containing Cefixime and Tellurite for Isolation of Escherichia coli O157:H7 from Radish Sprouts

2000 ◽  
Vol 66 (7) ◽  
pp. 3117-3118 ◽  
Author(s):  
Tomohiko Fujisawa ◽  
Shin Sata ◽  
Katsuhiro Aikawa ◽  
Takanori Takahashi ◽  
Shiro Yamai ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
The Other ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Other Hand ◽  
Radish Sprouts

ABSTRACT A modified version of sorbitol MacConkey medium containing cefixime and tellurite (CT-SMAC medium) was produced by adding salicin and 4-methylumbelliferyl-β-d-galactopyranoside to CT-SMAC medium; this medium was designated CT-SSMAC medium and was used to isolate Escherichia coli O157:H7 from radish sprouts. Of 101 non-E. coli bacteria isolated from radish sprouts that produced colorless colonies similar to colonies of E. coliO157:H7 grown on CT-SMAC medium, 92 (91%) formed colonies that were red to pink or were β-galactosidase negative and colorless on CT-SSMAC medium. On the other hand, colonies of E. coliO157:H7 strains were colorless and β-galactosidase positive on CT-SSMAC medium. Our results suggest that CT-SSMAC medium is more selective than CT-SMAC medium for isolating E. coliO157:H7.

scholarly journals Escherichia coli O157:H7 SURVIVAL IN TRADITIONAL AND LOW LACTOSE YOGURT DURING FERMENTATION AND COOLING PERIODS

2017 ◽  
Vol 18 (0) ◽  
Author(s):  
Camila Sampaio Cutrim ◽  
Raphael Ferreira de Barros ◽  
Robson Maia Franco ◽  
Marco Antonio Sloboda Cortez
Keyword(s):  
Escherichia Coli ◽  
The Other ◽  
Lactose Hydrolysis ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Gas Formation ◽  
Whole Milk ◽  
Milk Contamination ◽  
Different Types ◽  
Fermentation Period

Abstract The purpose of this study was to evaluate the behavior of E. coli O157:H7 during lactose hydrolysis and fermentation of traditional and low lactose yogurt. It also aimed to verify E. coli O157:H7 survival after 12 h of storage at 4 ºC ±1 ºC. Two different types of yogurts were prepared, two with whole milk and two with pre-hydrolyzed whole milk; in both groups one yogurt was inoculated with E. coli O157:H7 and the other one was not inoculated. The survival of E. coli and pH of yogurt were determined during fermentation and after 12-h refrigeration. The results showed that E. coli O157:H7 was able to grow during the fermentation period (from 4.34 log CFU.mL-1 to 6.13 log CFU.mL-1 in traditional yogurt and 4.34 log CFU.mL-1 to 6.16 log CFU.mL-1 in low lactose yogurt). The samples with E. coli O157:H7 showed gas formation and syneresis. Thus, E. coli O157:H7 was able to survive and grow during fermentation of traditional and low lactose yogurts affecting the manufacture technology. Moreover, milk contamination by E. coli before LAB addition reduces the growth of L. bulgaricus and S. thermophilus especially when associated with reduction of lactose content.

Simultaneous Enrichment of Shiga Toxin–Producing Escherichia coli O157 and O26 and Salmonella in Food Samples Using Universal Preenrichment Broth

2009 ◽  
Vol 72 (10) ◽  
pp. 2065-2070 ◽  
Author(s):  
MASASHI KANKI ◽  
KAZUKO SETO ◽  
JUNKO SAKATA ◽  
TETSUYA HARADA ◽  
YUKO KUMEDA
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Food Samples ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Significant Difference ◽  
Peptone Water ◽  
Radish Sprouts ◽  
Pork Samples ◽  
Better Than

Universal preenrichment broth (UPB) was compared with modified Escherichia coli broth with novobiocin (mEC+n) for enrichment of Shiga toxin–producing E. coli O157 and O26, and with buffered peptone water (BPW) for preenrichment of Salmonella enterica. Ten strains each of the three pathogens were inoculated into beef and radish sprouts following thermal, freezing, or no treatment. With regard to O157 and O26, UPB incubated at 42°C recovered significantly more cells from inoculated beef than UPB at 35°C and from radish sprout samples than UPB at 35°C and mEC+n. With regard to Salmonella, UPB incubated at 42°C was as effective as UPB at 35°C and BPW at recovering cells from beef and radish sprout samples. No significant difference was noted between the effectiveness of UPB at 42°C and UPB at 35°C or BPW in the recovery of Salmonella from 205 naturally contaminated poultry samples. By using UPB at 42°C, one O157:H7 strain was isolated from the mixed offal of 53 beef samples, 6 cattle offal samples, and 50 pork samples all contaminated naturally, with no pathogen inoculation. The present study found that UPB incubated at 42°C was as effective as, or better than, mEC+n for enrichment of O157 and O26 and comparable to BPW for preenrichment of Salmonella. These findings suggest that a great deal of labor, time, samples, and space may be saved if O157, O26, and Salmonella are enriched simultaneously with UPB at 42°C.

Testing of Bob Calf Fecal Swabs for the Presence of Escherichia coli O157:H7

1994 ◽  
Vol 57 (1) ◽  
pp. 70-72 ◽  
Author(s):  
DAVID R. MARTIN ◽  
PAUL M. UHLER ◽  
ANITA J. G. OKREND ◽  
JOSEPH Y. CHIU
Keyword(s):  
Escherichia Coli ◽  
The Other ◽  
Escherichia Coli O157 ◽  
Enrichment Method ◽  
Direct Smear ◽  
E Coli ◽  
Test Kit ◽  
Rectal Swabs

Rectal swabs were collected from 304 Bob calves (calves under 10 d old) brought to slaughter in the States of Washington (77 swabs), California (127 swabs), and Wisconsin (100 swabs). The swab samples were tested for the presence of Escherichia coli O157:H7 by the use of a direct smear method, enrichment method, and the use of the Petrifilm™ Test Kit-HEC-for hemorrhagic E. coli O157:H7 (3M Company, St. Paul, MN). The organism was not isolated from any of the samples by any method, though the 3M test kit did give 21 positive signals. Of these positive signals, three were shown to be caused by sorbitol-positive, O157-positive, H7-negative E. coli. The cause of the other 18 signals was not determined.

Fate of Escherichia coli O157:H7 in Ground Apples Used in Cider Production

1998 ◽  
Vol 61 (10) ◽  
pp. 1372-1374 ◽  
Author(s):  
TOMEKA L. FISHER ◽  
DAVID A. GOLDEN
Keyword(s):  
Escherichia Coli ◽  
Statistical Difference ◽  
The Other ◽  
Escherichia Coli O157 ◽  
Apple Cultivar ◽  
Mold Growth ◽  
E Coli ◽  
Significant Difference ◽  
Golden Delicious ◽  
Pathogen Populations

Survival of Escherichia coli O157:H7 in ground Golden Delicious, Red Delicious, Rome, and Winesap apples stored at 4, 10, and 25°C was determined. E. coli O157:H7 populations were monitored for up to 18 days (4°C), 12 days (10°C), and 5 days (25°C), when mold contamination became visible. At 25°C, Red Delicious apples supported survival of E. coli O157:H7 better (P < 0.05) than the other cultivars, followed by Golden Delicious and Rome apples, which were not statistically different (P > 0.05). Winesap apples were the least favorable (P < 0.05) for survival of E. coli O157:H7 at 25°C. E. coli O157:H7 was recovered at similar rates from Golden Delicious and Red Delicious apples, (P > 0.05), but pathogen populations increased in both cultivars (P < 0.05) during storage at 25°C. At 10°C, survival of E. coli O157:H7 was poorest (P < 0.05) in ground Red Delicious apples, while there was no significant difference in survival of E. coli O157:H7 among ground Golden Delicious, Rome, or Winesap cultivars (P > 0.05). When stored at 4°C, Golden Delicious and Rome apples were not statistically different in supporting survival of the pathogen (P > 0.05) and there was no statistical difference in the recovery of E. coli O157:H7 from ground Red Delicious, Rome, and Winesap apples (P > 0.05). In general, apple pH increased during storage and was associated with mold growth. Results of this investigation indicate that there is no trend toward a particular apple cultivar supporting survival of E. coli O157:H7. However, variation in apple pH during storage can negatively or positively influence E. coli O157:H7 survival at 25 °C.

Inhibition of Growth of Escherichia coli O157:H7 in Fresh Radish (Raphanus sativus L.) Sprout Production by Calcinated Calcium

1999 ◽  
Vol 62 (2) ◽  
pp. 128-132 ◽  
Author(s):  
M. L. BARI ◽  
H. KUSUNOKI ◽  
H. FURUKAWA ◽  
H. IKEDA ◽  
K. ISSHIKI ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Raphanus Sativus ◽  
Inhibitory Effect ◽  
Seed Extract ◽  
Escherichia Coli O157 ◽  
Experimental Conditions ◽  
E Coli ◽  
Inhibition Of Growth ◽  
Raphanus Sativus L ◽  
Radish Sprouts

The inhibitory effect of calcinated calcium on the growth of Escherichia coli O157:H7 during fresh radish (Raphanus sativus L.) sprout production was studied. It was revealed that the addition of 0.4% (wt/vol) calcinated calcium into radish sprouting medium which was artificially contaminated with E. coli O157:H7 (3.0 to 3.2 log CFU/ml) completely inhibited the growth or inactivated the microorganism. When radish seed extract was used instead of radish sprout production, the same extent of growth inhibition or inactivation was observed with much lower amounts (0.07%) of calcinated calcium under similar experimental conditions. The findings suggested that calcinated calcium may be useful to control E. coli O157:H7 contamination during the production of radish sprouts.

Potential Hazard of Radish Sprouts as a Vehicle of Escherichia coli O157:H7

1997 ◽  
Vol 60 (9) ◽  
pp. 1125-1127 ◽  
Author(s):  
Y. HARA-KUDO ◽  
H. KONUMA ◽  
M. IWAKI ◽  
F. KASUGA ◽  
Y. SUGITA-KONISHI ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Escherichia Coli O157 ◽  
Potential Hazard ◽  
E Coli ◽  
Radish Sprouts ◽  
Edible Parts

We studied the contamination of radish sprouts after exposure to Escherichia coli O157:H7-inoculated water in the laboratory. The edible parts, the cotyledons and hypocotyl, became heavily contaminated with E. coli O157:H7 when they were grown from seeds soaked in E. coli O157:H7-inoculated water. These same parts became contaminated with E. coli O157:H7 when their roots were dipped into E. coli O157:H7-inoculated water. These findings suggest that E. coli O157:H7 contamination in the edible parts of radish sprouts could pose a serious hazard if the seeds or hydroponic water are contaminated with the bacterium.

Bacteria and Virus Removal from Secondary Effluent in Sand and Red Mud Columns

1991 ◽  
Vol 23 (1-3) ◽  
pp. 261-270 ◽  
Author(s):  
Goen E. Ho ◽  
Robyn A. Gibbs ◽  
Kuruvilla Mathew
Keyword(s):  
Escherichia Coli ◽  
Red Mud ◽  
Breakthrough Curves ◽  
The Other ◽  
Column Experiments ◽  
Secondary Effluent ◽  
Soil Columns ◽  
Virus Removal ◽  
E Coli ◽  
Other Hand

Column experiments were conducted to determine the improvement in the removal of Escherichia coli, Salmonella adelaide and poliovirus-1 through sands by amendment with bauxite refining residue. The residue (red mud) was neutralized using 5 % gypsum and incorporated to form 30% of the amended sands. In 65 cm long soil columns the removal of the three organisms in the amended sand columns was excellent with over seven orders of magnitude reduction in concentration. Removal in unamended sands was poor. From breakthrough curves in unamended sand columns filtration, die-off and adsorption all appear to play a role in organism removal. The results also show that E. coli can be used as an indicator for contamination, though S.adelaide was less efficiently removed than E. coli. Poliovirus was on the other hand better removed than E. coli.

scholarly journals Genetic Plurality of OXA/NDM-Encoding Features Characterized From Enterobacterales Recovered From Czech Hospitals

2021 ◽  
Vol 12 ◽  
Author(s):  
Katerina Chudejova ◽  
Lucie Kraftova ◽  
Vittoria Mattioni Marchetti ◽  
Jaroslav Hrabak ◽  
Costas C. Papagiannitsis ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
High Risk ◽  
Klebsiella Pneumoniae ◽  
The Other ◽  
Travel History ◽  
Genetic Environment ◽  
E Coli ◽  
Resistance Determinants ◽  
Other Hand ◽  
Previous Hospitalization

The aim of this study was to characterize four Enterobacterales co-producing NDM- and OXA-48-like carbapenemases from Czech patients with travel history or/and previous hospitalization abroad. Klebsiella pneumoniae isolates belonged to “high risk” clones ST147, ST11, and ST15, while the Escherichia coli isolate was assigned to ST167. All isolates expressed resistance against most β-lactams, including carbapenems, while retaining susceptibility to colistin. Furthermore, analysis of WGS data showed that all four isolates co-produced OXA-48- and NDM-type carbapenemases, in different combinations (Kpn47733: blaNDM–5 + blaOXA–181; Kpn50595: blaNDM–1 + blaOXA–181; Kpn51015: blaNDM–1 + blaOXA–244; Eco52418: blaNDM–5 + blaOXA–244). In Kpn51015, the blaOXA–244 was found on plasmid p51015_OXA-244, while the respective gene was localized in the chromosomal contig of E. coli Eco52418. On the other hand, blaOXA–181 was identified on a ColKP3 plasmid in isolate Kpn47733, while a blaOXA–181-carrying plasmid being an IncX3-ColKP3 fusion was identified in Kpn50595. The blaNDM–1 gene was found on two different plasmids, p51015_NDM-1 belonging to a novel IncH plasmid group and p51015_NDM-1 being an IncFK1-FIB replicon. Furthermore, the blaNDM–5 was found in two IncFII plasmids exhibiting limited nucleotide similarity to each other. In both plasmids, the genetic environment of blaNDM–5 was identical. Finally, in all four carbapenemase-producing isolates, a diverse number of additional replicons, some of these associated with important resistance determinants, like blaCTX–M–15, arr-2 and ermB, were identified. In conclusion, this study reports the first description of OXA-244-producing Enterobacterales isolated from Czech hospitals. Additionally, our findings indicated the genetic plurality involved in the acquisition and dissemination of determinants encoding OXA/NDM carbapenemases.

scholarly journals Effects of Organic Antagonists of Ca2+, Na+, and K+ on Chemotaxis and Motility ofEscherichia coli

2000 ◽  
Vol 182 (17) ◽  
pp. 4856-4861 ◽  
Author(s):  
Louis S. Tisa ◽  
Jeff J. Sekelsky ◽  
Julius Adler
Keyword(s):  
Escherichia Coli ◽  
Bacterial Chemotaxis ◽  
Animal Research ◽  
The Other ◽  
Ofescherichia Coli ◽  
Channel Blockers ◽  
Tetraethylammonium Chloride ◽  
E Coli ◽  
Other Hand ◽  
Nanomolar Range

ABSTRACT Various Ca2+ antagonists used in animal research, many of them known to be Ca2+ channel blockers, inhibitedEscherichia coli chemotaxis (measured as entry of cells into a capillary containing attractant). The most effective of these, acting in the nanomolar range, was ω-conotoxin GVIA. The next most effective were gallopamil and verapamil. At concentrations around 100-fold higher than that needed for inhibition of chemotaxis, each of these antagonists inhibited motility (measured as entry of cells into a capillary lacking attractant). Various other Ca2+antagonists were less effective, though chemotaxis was almost always more sensitive to inhibition than was motility. Cells treated with each of these Ca2+ antagonists swam with a running bias, i.e., tumbling was inhibited. Similarly, some Na+ antagonists used in animal research inhibited bacterial chemotaxis. E. coli chemotaxis was inhibited by saxitoxin at concentrations above 10−7 M, while more than 10−4 M was needed to inhibit motility. Cells treated with saxitoxin swam with a tumbling bias. In the case of other Na+ antagonists in animals, aconitine inhibited bacterial chemotaxis 10 times more effectively than it inhibited motility, and two others inhibited chemotaxis and motility at about the same concentration. In the case of K+ antagonists used in animal research, 4-aminopyridine blocked E. coli chemotaxis between 10−3 M and, totally, 10−2 M, while motility was not affected at 10−2 M; on the other hand, tetraethylammonium chloride failed to inhibit either chemotaxis or motility at 10−2 M.

Effect of Rumen Protozoa on Escherichia coli O157:H7 in the Rumen and Feces of Specifically Faunated Sheep

2010 ◽  
Vol 73 (12) ◽  
pp. 2197-2202 ◽  
Author(s):  
K. STANFORD ◽  
S. J. BACH ◽  
T. P. STEPHENS ◽  
T. A. McALLISTER
Keyword(s):  
Escherichia Coli ◽  
Mixed Population ◽  
The Other ◽  
Escherichia Coli O157 ◽  
Fecal Shedding ◽  
Predator Prey ◽  
Treatment Groups ◽  
E Coli ◽  
Rumen Protozoa ◽  
Barley Silage

The effects of rumen protozoal populations on ruminal populations and fecal shedding of Escherichia coli O157:H7 were evaluated by using specifically faunated sheep. Nine fauna-free sheep (three animals per treatment) were inoculated with Dasytricha spp. (DAS sheep); with mixed population A (PopA) comprising Entodinium spp., Isotricha spp., Diplodinium spp., and Polyplastron spp.; or with mixed population B (PopB) comprising Entodinium spp., Isotricha spp., Dasytricha spp., and Epidinium spp.; six sheep were maintained fauna-free (FF sheep) to serve as controls. Sheep were fed barley silage–based diets, and treatment groups were housed in isolated rooms. Sheep were inoculated orally with 1010 CFU of a four-strain mixture of nalidixic acid–resistant E. coli O157:H7. Samples of ruminal fluid and feces were collected over 77 days. Polyplastron spp. were detected in only one sheep in PopA, and Dasytricha spp. were detected only once within the PopB cohort. Sheep in the DAS group were 2.03 times more likely (P < 0.001) to shed E. coli O157:H7 than were those in the other three treatments, whereas the PopB sheep were less likely (0.65; P < 0.05) to shed this bacterium. The likelihood of harboring ruminal E. coli O157:H7 also tended (P = 0.06) to be higher in DAS and was lower (P < 0.01) in FF than in other cohorts. Possibly, Dasytricha spp. had a hosting effect, and Epidinium spp. had a predatory relationship, with E. coli O157:H7. Additional study into predator-prey and hosting relationships among rumen protozoa and E. coli O157:H7 is warranted.

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