scholarly journals Inativação de microrganismos indicadores de contaminação fecal por radiação ultravioleta e avaliação dos fenômenos de fotorreativação e recuperação no escuro

2018 ◽  
Vol 23 (5) ◽  
pp. 987-994
Author(s):  
Carlos Raphael Pedroso ◽  
Jeanette Beber de Souza ◽  
Thaís Kovalski ◽  
Carlos Magno de Sousa Vidal ◽  
Kelly Geronazzo Martins
Keyword(s):  
Escherichia Coli ◽  
Clostridium Perfringens ◽  
E Coli

RESUMO Esta pesquisa teve como objetivo avaliar o desempenho da radiação ultravioleta (UV) para a desinfecção de efluente final de estação de tratamento de esgoto (ETE) sanitário municipal, em escala de bancada de laboratório e operação em batelada. Foram analisadas as interferências dos parâmetros operacionais tempo de exposição (s) à radiação e altura de lâmina líquida (cm) do efluente no reator UV. A eficiência do processo de desinfecção foi avaliada empregando os microrganismos indicadores Clostridium perfringens (C. perfringens), colifagos, Escherichia coli (E. coli) e coliformes totais (CT). Após a desinfecção, foram avaliados os fenômenos de recuperação microbiológica fotorreativação e recuperação no escuro para E. coli e CT. Os resultados indicaram efetiva inativação dos microrganismos indicadores à radiação UV no decorrer do tempo de exposição, o que foi comprovado estatisticamente pela ANOVA de medidas repetidas. C. perfringens foi o microrganismo que apresentou a maior resistência à inativação. Nos ensaios de recuperação microbiológica, ambos os mecanismos foram considerados insignificantes, o que foi comprovado estatisticamente pelos testes t de Student (dados paramétricos) e Wilcoxon (dados não paramétricos). Em todas as análises, o nível de significância foi de 5%.

Growth of Selected Cross-Contaminating Bacterial Pathogens on Beef and Fish at 15 and 35°C+

1994 ◽  
Vol 57 (4) ◽  
pp. 337-340 ◽  
Author(s):  
AJIBOLA O. FAPOHUNDA ◽  
KENNETH W. MCMILLIN ◽  
DOUGLAS L. MARSHALL ◽  
W. M. WAITES
Keyword(s):  
Escherichia Coli ◽  
Clostridium Perfringens ◽  
Aeromonas Hydrophila ◽  
Growth Response ◽  
Cross Contamination ◽  
Limited Growth ◽  
E Coli ◽  
Fish Samples ◽  
Conditioning Temperature ◽  
The Tropics

Isolates of Escherichia coli and Clostridium perfringens from beef and Aeromonas hydrophila from fish were examined for their ability to survive and grow as cross-contaminates on nonnative tissues at simulated ambient (35°C) and aging/conditioning (15°C) temperatures of handling and retailing found in the tropics. Growth of all isolates over a 10-h period was greater (P < 0.05) on their native tissues at both temperatures. The aging/conditioning temperature effectively limited growth of E. coli and A. hydrophila to less than l-logl0 CFU/g and prevented growth of C. perfringens on beef and fish samples. All three isolates demonstrated characteristic mesophilic growth response on both tissues at 35°C during the 10-h retail period. The study suggests that two muscle food products could be jointly handled to efficiently use available storage/haulage capacity in tropical countries. Potential savings in space, labor and energy would be made if cross-contamination between the two products is minimized by available packaging and sanitizing technologies.

scholarly journals Susceptibility of Escherichia coli and Clostridium perfringens to sucrose monoesters of capric and lauric acid

2014 ◽  
Vol 59 (No. 8) ◽  
pp. 374-380
Author(s):  
E. Skřivanová ◽  
Š. Pražáková ◽  
O. Benada ◽  
P. Hovorková ◽  
MarounekM
Keyword(s):  
Escherichia Coli ◽  
Antibacterial Activity ◽  
Clostridium Perfringens ◽  
Lauric Acid ◽  
Cytoplasmic Membrane ◽  
E Coli ◽  
Enteropathogenic Bacteria ◽  
Viable Cells ◽  
Transmission Electron ◽  
Cytoplasmic Structures

The sucrose monoesters of capric and lauric acid were tested for their antibacterial activity towards two foodborne enteropathogenic bacteria &ndash; Escherichia coli (CCM 3954 &ndash; serotype O6 and E22 &ndash; serotype O103) and Clostridium perfringens (CNCTC 5459 and CIP 105178). Antibacterial activity was evaluated by the plating technique. Sucrose monocaprate significantly decreased the number of viable cells of E. coli at all tested concentrations (0.1&ndash;5 mg/ml). The overnight incubation of C. perfringens with the sucrose ester of lauric acid at 0.1&ndash;5 mg/ml reduced the number of viable cells below the detection limit (2 log<sub>10</sub> CFU/ml). Incubating E. coli CCM 3954 and C. perfringens CNCTC 5459 with monoesters (0.1 and 2 mg/ml) did not influence the K<sup>+</sup> permeability of the cytoplasmic membrane in cells during a 2.5-minute treatment. A 30-minute incubation of E. coli CCM 3954 and C. perfringens CNCTC 5459 with esters (0.1 and 2 mg/ml) revealed damage to cytoplasmic structures, as observed by transmission electron microscopy. &nbsp;

Fate of Pathogens Inoculated onto Vacuum-Packaged Sliced Hams to Simulate Contamination During Packaging1

1979 ◽  
Vol 42 (6) ◽  
pp. 464-469 ◽  
Author(s):  
M. E. STILES ◽  
L.-K. NG
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Bacillus Cereus ◽  
Clostridium Perfringens ◽  
Subsequent Treatment ◽  
Vacuum Packaging ◽  
E Coli ◽  
Survival And Growth ◽  
And Staphylococcus Aureus

Ham and chopped ham from two manufacturers were contaminated with five enteropathogens: Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus, at time of slicing and vacuum-packaging, to simulate contamination by manufacturer. Subsequent treatment of the samples, representing sound and undesirable retail handling and consumer use conditions, indicated marked differences in the fate of the pathogens between these products and within product type between the two manufacturers. Greatest differences were observed between the chopped ham products. All pathogens, except C. perfringens, grew actively in fresh ham and chopped ham with abusive holding at 30 and 21 C. After storage at 4 or 10 C for 30 days, B. cereus and C. perfringens were no longer detected, even after subsequent holding at 30 or 21 C for 24 h. E. coli survival and growth was variable, S. typhimurium survived well and grew under some conditions and S. aureus was generally inhibited at high levels of competition.

scholarly journals Poikilothermic Animals as a Previously Unrecognized Source of Fecal Indicator Bacteria in a Backwater Ecosystem of a Large River

2018 ◽  
Vol 84 (16) ◽  
Author(s):  
Christina Frick ◽  
Julia Vierheilig ◽  
Rita Linke ◽  
Domenico Savio ◽  
Horst Zornig ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Clostridium Perfringens ◽  
Fecal Indicator Bacteria ◽  
Indicator Bacteria ◽  
Primary Sources ◽  
Fecal Indicator ◽  
Content Type ◽  
E Coli ◽  
High Concentrations ◽  
Intestinal Enterococci

ABSTRACTQuantitative information regarding the presence ofEscherichia coli, intestinal enterococci, andClostridium perfringensin poikilotherms is notably scarce. Therefore, this study was designed to allow a systematic comparison of the occurrence of these standard fecal indicator bacteria (SFIB) in the excreta of wild homeothermic (ruminants, boars, carnivores, and birds) and poikilothermic (earthworms, gastropods, frogs, and fish) animals inhabiting an alluvial backwater area in eastern Austria. With the exception of earthworms, the average concentrations ofE. coliand enterococci in the excreta of poikilotherms were equal to or only slightly lower than those observed in homeothermic excreta and were 1 to 4 orders of magnitude higher than the levels observed in the ambient soils and sediments. Enterococci reached extraordinarily high concentrations in gastropods. Additional estimates of the daily excreted SFIB (E. coliand enterococcus) loads (DESL) further supported the importance of poikilotherms as potential pollution sources. The newly established DESL metric also allowed comparison to the standing stock of SFIB in the sediment and soil of the investigated area. In agreement with its biological characteristics, the highest concentrations ofC. perfringenswere observed in carnivores. In conclusion, the long-standing hypothesis that only humans and homeothermic animals are primary sources of SFIB is challenged by the results of this study. It may be necessary to extend the fecal indicator concept by additionally considering poikilotherms as potential important primary habitats of SFIB. Further studies in other geographical areas are needed to evaluate the general significance of our results. We hypothesize that the importance of poikilotherms as sources of SFIB is strongly correlated with the ambient temperature and would therefore be of increased significance in subtropical and tropical habitats and water resources.IMPORTANCEThe current fecal indicator concept is based on the assumption that the standard fecal indicator bacteria (SFIB)Escherichia coli, intestinal enterococci, andClostridium perfringensmultiply significantly only in the guts of humans and other homeothermic animals and can therefore indicate fecal pollution and the potential presence of pathogens from those groups. The findings of the present study showed that SFIB can also occur in high concentrations in poikilothermic animals (i.e., animals with body temperatures that vary with the ambient environmental temperature, such as fish, frogs, and snails) in an alluvial backwater area in a temperate region, indicating that a reconsideration of this long-standing indicator paradigm is needed. This study suggests that poikilotherms must be considered to be potential primary sources of SFIB in future studies.

Clostridium perfringens as an Indicator of Hygienic Quality of Depurated Shellfish

1986 ◽  
Vol 49 (1) ◽  
pp. 33-36 ◽  
Author(s):  
ROBERT H. MADDEN ◽  
H. BULLER ◽  
D. W. McDOWELL
Keyword(s):  
Escherichia Coli ◽  
Clostridium Perfringens ◽  
Fecal Pollution ◽  
The Other ◽  
Acceptable Level ◽  
Laboratory Studies ◽  
E Coli ◽  
Commercial Practice ◽  
Considerable Period

A comparison of the recoveries of Clostridium perfringens, Escherichia coli and Streptococcus faecalis from naturally and artificially contaminated mussels and oysters was made. Only C. perfringens was regularly recovered from naturally contaminated shellfish. Laboratory studies showed that this was due to C. perfringens spores retaining viability significantly longer than vegetative cells of the other organisms tested, under marine conditions. Over 97% of presumptive C. perfringens colonies were confirmed as positive. A survey of mussels at 24 sites, over ca. 60 km of coastline, found C. perfringens at 23 but E. coli at only two of the sites. Therefore, enumeration of C. perfringens can indicate fecal pollution where enumeration of E. coli shows none. Also, confirmation of presumptive colonies may not be required, rendering enumeration more rapid. Despite the greater persistence of C. perfringens spores, studies in a commercial depuration tank showed that oysters were cleansed to an acceptable level using a standard 48-h immersion. Depuration was found to be essential because all three organisms tested survived for a considerable period of time in oysters stored dry at 4°C, which is normal commercial practice.

Microbiological Quality of Hot Meals Served by Airlines

1998 ◽  
Vol 61 (8) ◽  
pp. 1052-1056 ◽  
Author(s):  
MAIJA HATAKKA
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Clostridium Perfringens ◽  
Pathogenic Bacteria ◽  
Microbiological Quality ◽  
Geometric Means ◽  
E Coli ◽  
The World ◽  
And Staphylococcus Aureus

The microbiological quality of 1,012 hot meals served on aircraft was studied in 1991 to 1994. The material included dishes prepared in 33 countries all over the world. The geometric means of aerobic colony counts and Escherichia coli were significantly lower in breakfasts (P &lt; 0.05) than in main dishes. Pathogenic bacteria were found in 30 samples (3.0%), Bacillus cereus being the most common pathogen. The frequencies of B. cereus and Staphylococcus aureus did not differ between breakfasts and main dishes. Many of the samples exceeded the minimum acceptable microbiological standards recommended by the Association of European Airlines (AEA) for E. coli, S. aureus, B. cereus, Clostridium perfringens, and Salmonella; i.e., 8.2%, 0.6%, 0.7%, 0.7% and 0.3%, respectively. There were considerable differences in aerobic colony counts and E. coli counts between countries where the food was prepared.

scholarly journals Characterization of virulence factors in Escherichia coli isolated from diarrheic and healthy calves in Austria shedding various enteropathogenic agents

2009 ◽  
Vol 54 (No. 1) ◽  
pp. 1-11 ◽  
Author(s):  
C. Herrera-Luna ◽  
D. Klein ◽  
G. Lapan ◽  
S. Revilla-Fernandez ◽  
B. Haschek ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Factors ◽  
Clostridium Perfringens ◽  
Shiga Toxin ◽  
Systemic Disease ◽  
Toxin Gene ◽  
Detection Rates ◽  
E Coli ◽  
Faecal Samples ◽  
Control And Prevention

Faecal samples from 230 diarrhoeic and healthy calves aged 0–6 weeks, from 100 farms in Austria, were examined between October 2004 and February 2005 for the presence of bacteria, especially Shiga toxin-producing <I>Escherichia coli </I> (STEC), viruses and parasites. <I>Escherichia coli</I> was detected in 17% of all the faecal samples and was more prevalent in healthy calves. However, <I>E. coli</I> F5 was identified only in one calf without diarrhoea. Overall, 35 out of the 230 (15.2%) samples analyzed carried the Shiga toxin gene: <I>stx1, stx2</I> or both <I>stx1</I> and<I> stx2</I> in their faeces, STEC. Nevertheless, out of 39 pathogenic <I>E. coli</I> positive samples observed, only two carried the Shiga toxin genes: <I>stx1</I>, in a diarrhoeic calf and both <I>stx1</I> and <I>stx2</I> in a healthy calf. <I>eaeA</I> and <I>Ehly</I> genes were detected more frequently in the strains from diarrhoeic calves 57.1% and 50.0%, respectively. <I>Clostridium perfringens</I> was detected in twenty-one samples, the most prevalent toxin type of <I>Clostridium perfringens</I> was found to be type A (76.2%). Other bacteria such as <I>Klebsiella</I> spp. and <I>Proteus</I> spp. were present in 1.3% and 0.4% of all samples. <I>Salmonella</I> spp. was not detected. The detection rates of other enteropathogens were 25.7% bovine coronavirus, 11.7% <I>Cryptosporidium</I> spp., 10.4% <I>Eimeria</I> spp., 9.1% group A rotavirus and <I>Giardia</I> spp. 6.1%. We demonstrated the presence of the STEC virulence genes in healthy and diarrhoeic Austrian calves but the importance of the virulence factors of STEC (<I>stx1, stx2, eae</I> and <I>Ehly</I>) in calf diarrhoea and systemic disease is not well defined. Therefore, further studies are necessary to identify reservoirs or potential sources of virulent STEC strains in order to establish control and prevention strategies for STEC associated diseases in animals and humans.

scholarly journals Enhanced expression of recombinant beta toxin of Clostridium perfringens type B using a commercially available Escherichia coli strain

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Fatemah Bakhshi ◽  
Reza Pilehchian Langroudi ◽  
Bahram Golestani Imani
Keyword(s):  
Escherichia Coli ◽  
Recombinant Protein ◽  
Clostridium Perfringens ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Toxin Gene ◽  
Type B ◽  
Iptg Induction ◽  
E Coli ◽  
Beta Toxin

Clostridium perfringens beta toxin is only produced by types B and C and plays an important role in many human and animal diseases, causing fatal conditions that originate in the intestines. We compared the expression of C. perfringens type B vaccine strain recombinant beta toxin gene in the Escherichia coli strains RosettaTM(DE3) and BL21(DE3). The beta toxin gene was extracted from pJETβ and ligated with pET22b(+). pET22β was transformed into E. coli strains BL21(DE3) and RosettaTM(DE3). Recombinant protein was expressed as a soluble protein after isopropyl β-D-1-thiogalactopyranoside (IPTG) induction in strain RosettaTM(DE3) but not in BL21(DE3). Expression was optimised by growing recombinant cells at 37 °C and at an induction of 0.5 mM, 1 mM, 1.5 mM IPTG. Expression was evaluated using sodium dodecyl sulfate Polyacrylamide gel electrophoresis (SDS-PAGE). The recombinant protein was purified via Ni-NTA and was analysed using western blot. We concluded that E. coli strain RosettaTM(DE3) can enhance the expression of C. perfringens recombinant beta toxin.Keywords: C. perfringens beta toxin (CPB); expression; RosettaTM; BL21

scholarly journals COMPARISON OF ANTIBACTERIAL ACTIVITY OF HONEY AGAINST AEROBIC AND ANAEROBIC BACTERIA

2021 ◽  
pp. 41-43
Author(s):  
S. DHANARAJ ◽  
S. S. M. UMAMAGESWARI ◽  
M. MALAVIKA ◽  
G. BHUVANESHWARI
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Clostridium Perfringens ◽  
Anaerobic Bacteria ◽  
The Other ◽  
E Coli ◽  
Diffusion Technique ◽  
Aerobic And Anaerobic

Objective: To compare the antibacterial activity of honey against aerobic and anaerobic bacteria. Methods: Honey is extracted from the honey comb by trained persons. Antimicrobial activity of honey is performed by Agar Cup Diffusion technique for 3 bacteria Staphylococcus aureus, E. coli and Clostridium perfringens. Results: By performing the technique with proper guidance, it is observed that the Staphylococcus aureus specimen shows sensitivity to honey whereas the other two specimens Escherichia coli and clostridium perfringens doesn’t show any sensitivity to honey. Conclusion: Due to its vast antibacterial activity of honey, it can be used along with other antibiotics to increase its efficiency.

scholarly journals COMPARISON OF ANTIBACTERIAL ACTIVITY OF GARLIC AGAINST AEROBIC AND ANAEROBIC BACTERIA

2021 ◽  
pp. 44-46
Author(s):  
K. G. DHANUSH ◽  
S. S. M. UMAMAGESWARI ◽  
M. MALAVIKA ◽  
G. BHUVANESHWARI
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Clostridium Perfringens ◽  
Anaerobic Bacteria ◽  
The Other ◽  
E Coli ◽  
Diffusion Technique ◽  
Aerobic And Anaerobic

Objective: To compare the antibacterial activity of garlic against aerobic and anaerobic bacteria. Methods: Antimicrobial activity of garlic is performed by Agar cup diffusion technique for 3 bacteria Staphylococcus aureus, E. coli and clostridium perfringens. Results: By performing the technique with proper guidance, it is observed that the Staphylococcus aureus specimen shows sensitivity to garlic whereas the other two specimens Escherichia coli and clostridium perfringens doesn’t show any sensitivity to garlic. Conclusion: Due to its vast antibacterial activity of garlic, it can be used along with other antibiotics to increase its efficiency.

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