Category Archives: Klebsiella

Research – Contribution of MALDI-TOF-MS-based principal component analysis for distinguishing foodborne pathogens

Wiley Online

Abstract

Foodborne diseases are important to determine bacteria in strain level, which are analyzed by library-based devices and bioinformatics-enabled. The aim of this study was to investigate the contribution of principal component analysis (PCA) with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to distinguish according to the differences of bacterial strains as rapidly screening of foodborne bacteria. The MALDI-TOF-MS-based PCA analysis was used for differentiating bacterial strains isolated from ready-to-eat foods. According to the results of PCA analysis, the percentages of distance and proximity between species were evaluated by composite correlation indexes (CCI). Bacillus cereus were detected in burghul salad (BC1) and macaroni salad (BC2) taken from the SB2-snack bar, and the similarity rate was determined as 97%. Three other B. cereus bacteria (BC3, BC4, and BC5) in the same cluster were also isolated from salads collected from SB4-snack bar. The similarity of Klebsiella pneumoniae bacteria, which have the codes KP1 and KP2, isolated from macaroni salad and burghul salad taken from the SB2 snack bar respectively were 96%. Additionally, the CCI values of two E. coli strains in burghul (EC1) salad and Russian salad (EC2) in the same sampling point (SB1) were determined as 97%. In conclusion, this analysis with MALDI-TOF-MS based PCA has revealed the relationships between bacteria genera and species, beyond just the identification of bacteria and the rapid screening of bacteria in perishable foodstuffs. Similarities between bacterial strains identified for different samples from the same sampling point suggested that there were not adequate hygiene rules and storage requirements were not followed.

Research – Report of the Scientific Committee of the Spanish Agency for Food Safety and Nutrition (AESAN) on the prospection of biological ha-zards of interest in food safety in Spain (2)

AESAN

This report addresses the prospection of biological hazards for some types of food that may pose a risk to the population and that are not currently included in the official control programs in Spain.

It completes and updates the 2018 report by the Scientific Committee of the Spanish Agency for Food Safety and Nutrition (AESAN, 2018). A number of bacteria that are significant contributors to nosocomial infections due to the increase in the number of multi-resistant strains of Acinetobacter spp. ,Klebsiella pneumoniae and Pseudomonas aeruginosa are listed first.

It is also addressed the study of the prevalence and possible control of Bacillus cereus and Cronobacter spp. presence in cereal flours and others, the revision of Campylobacter jejuni and/or Campylobacter coli in meats other than poultry, as well as the study of Shigatoxin-producing Escherichia coli. These latter two biological agents are much better known from the food control perspective, although there are control measures for Campylobacter spp. in poultry meat and not in other types of meat such as beef or pork and in the case of E. coli, producers of Shiga toxins, the control of this particular type of pathogenic strains in food has not been specifically addressed either.

Finally, tick-borne viral encephalitis, which can be transmitted to humans through the consumption of raw milk or raw dairy products, has been indicated as a viral hazard. The prospective study shows the need to determine the prevalence of multi-resistant bacteria of Acinetobacter baumannii, K. pneumoniae and P. aeruginosa in foods in Spain, especially in ready-to-eat foods such as salads and fresh plant-based foods. This is especially important due to the lack of data on the prevalence of these bacteria in foods in Spain. However, food research is carried out in neighbouring countries.

It is also necessary to include C. jejuni and/or C. coli in the investigations of beef and pork, since the incidence of these foodborne pathogens in humans is not explained solely by the presence of these agents in poultry meat, being their presence in other animals for slaughter also evident. Similarly, outbreaks of Shiga toxin-producing E. coli have been reported in Spain over the last 25 years, which makes it advisable to control them in beef, raw milk and leafy vegetables.

With regard to Cronobacter spp. and B. cereus, the importance of these agents can be demonstrated given their survival in powdery materials such as flours of different origins, including cereals, although the reported outbreaks do not seem to indicate a high prevalence. As regards the only viral hazard mentioned, it should be noted that the wide dispersion of the ticks that can transmit this virus, together with the potential consumption of raw milk, makes it advisable to investigate it in raw milk products.

However, the study of the actual infective capacity of this virus is not easy to establish with simple analytical methods. With this last exception, research for controlling all these biological hazards in food is possible, with classical or advanced methodologies that are robust enough, available for each case.

Research – ESBL- and Carbapenemase-Producing Escherichia coli and Klebsiella pneumoniae among Bivalves from Portuguese Shellfish Production Areas

MDPI

Abstract

Bivalves are filter-feeding organisms and biomarkers of bacterial pollution. Our study aimed to analyze the occurrence and characteristics of extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Escherichia coli among bivalves. A total of 522 bivalve samples were collected along Portuguese shellfish production areas. Homogenized samples were screened for E. coli contamination on corresponding selective plates, allowing for concomitant growth of Klebsiella pneumoniaeE. coli growth was observed in 39% of the samples. Subsequent selective screening identified nine samples (4.4%) contaminated with ESBL producers, corresponding to E. coli (n = 7) and K. pneumoniae (n = 2), while a single carbapenemase-producing K. pneumoniae (0.5%) was identified. ESBLs were all CTX-M-types commonly identified in human isolates, i.e., CTX-M-32 (n = 4), CTX-M-15 (n = 4), and CTX-M-14 (n = 1). The carbapenemase producer harbored the blaGES-5 gene located on a ColE plasmid. Clonality was evaluated by multilocus sequence typing, identifying E. coli backgrounds as ST10, ST23, ST540, ST617, ST746, SLV206, and SLV2325, commonly identified among environmental and human strains. The K. pneumoniae isolates belonged to ST834, ST15, and DLV644. The occurrence of ESBL- and carbapenemase-producing Enterobacteriaceae in bivalves reveals how the marine environment constitutes a reservoir of critical bacterial pathogens, thus potentially representing a risk to human health.

Research – Repeated cross-sectional study identifies differing risk factors associated with microbial contamination in common food products in the United Kingdom

Science Direct

Abstract

All foods carry microbes, many of which are harmless, but foods can also carry pathogens and/or microbial indicators of contamination. Limited information exists on the co-occurrence of microbes of food safety concern and the factors associated with their presence. Here, a population-based repeated cross-sectional design was used to determine the prevalence and co-occurrence of Escherichia coli, Klebsiella spp., Salmonella spp. and Vibrio spp. in key food commodities – chicken, pork, prawns, salmon and leafy greens. Prevalence in 1,369 food samples for these four target bacterial genera/species varied, while 25.6% of all samples had at least two of the target bacteria and eight different combinations of bacteria were observed as co-occurrence profiles in raw prawns. Imported frozen chicken was 6.4 times more likely to contain Salmonella than domestic chicken, and imported salmon was 5.5 times more likely to be contaminated with E. coli. Seasonality was significantly associated with E. coli and Klebsiella spp. contamination in leafy greens, with higher detection in summer and autumn. Moreover, the odds of Klebsiella spp. contamination were higher in summer in chicken and pork samples. These results provide insight on the bacterial species present on foods at retail, and identify factors associated with the presence of individual bacteria, which are highly relevant for food safety risk assessments and the design of surveillance programmes.

Research- Repeated cross-sectional study identifies differing risk factors associated with microbial contamination in common food products in the United Kingdom

Science Direct

Highlights

E. coli was found in 29–99% of the five food types studied.

Salmonella was higher in imported frozen chicken than domestic chilled chicken.

E. coli and Klebsiella detection were higher in summer and autumn for leafy greens.

Klebsiella detection was higher in summer for chicken and pork.

Vibrio contamination was common in raw prawns at 60.4%.

Abstract

All foods carry microbes, many of which are harmless, but foods can also carry pathogens and/or microbial indicators of contamination. Limited information exists on the co-occurrence of microbes of food safety concern and the factors associated with their presence. Here, a population-based repeated cross-sectional design was used to determine the prevalence and co-occurrence of Escherichia coli, Klebsiella spp., Salmonella spp. and Vibrio spp. in key food commodities – chicken, pork, prawns, salmon and leafy greens. Prevalence in 1,369 food samples for these four target bacterial genera/species varied, while 25.6% of all samples had at least two of the target bacteria and eight different combinations of bacteria were observed as co-occurrence profiles in raw prawns. Imported frozen chicken was 6.4 times more likely to contain Salmonella than domestic chicken, and imported salmon was 5.5 times more likely to be contaminated with E. coli. Seasonality was significantly associated with E. coli and Klebsiella spp. contamination in leafy greens, with higher detection in summer and autumn. Moreover, the odds of Klebsiella spp. contamination were higher in summer in chicken and pork samples. These results provide insight on the bacterial species present on foods at retail, and identify factors associated with the presence of individual bacteria, which are highly relevant for food safety risk assessments and the design of surveillance programmes.

Research – Microbiological and physicochemical properties of farm bulk tank milk and antimicrobial resistance of its dominant bacteria

Wiley Online

Abstract

This study determined the antibiotic resistance of the dominant bacteria in the 85 farm BTMs according to the guidelines recommended by the epidemiological cutoff values in the EUCAST. In addition, some physicochemical and microbiological properties of farm BTMs were investigated. The milk samples were divided into two groups according to their SCC values. The milk samples with higher SCC than 400,000 cells mL−1 were further examined bacteriologically, and the antibiotic resistance of isolates was determined. The average TAMB value was 6.34 log CFU/mL in farm BTM. It was found that high-SCC values did not affect other physicochemical properties of BTM samples, such as fat, protein and total solids, except for lactose content. Seventy-two strains were isolated from 45 bulk milk samples. The most prevalent bacteria were Enterococcus spp. (23.61%). The other isolates were Citrobacter spp. (12.5%), Staphylococcus spp. (12.51%), Serratia spp. (11.12%), Klebsiella spp. (9.72%), Bacillus spp. (9.72%), and Enterobacter spp. (8.33%). In antibiotic resistance analysis, 52.6% of Enterobacterales isolates showed cefoxitin resistance, and nine Enterobacterales isolates were determined as the presumptive ESBL producers. None of them was confirmed as ESBL producers. Moreover, MDR was detected in 83.3% of Enterobacter spp. isolates and all Bacillus spp. isolates. The over and inappropriate use of antibiotics in mastitis treatment may cause antibiotic-resistant microorganisms in milk. It was found that 52.7% of the isolated bacteria were MDR, which could pose a risk to public health and food safety, with the consumer’s increasing interest in consuming raw milk.

Research – Antibacterial activity of sweet orange (Citrus sinensis) juice extract on selected bacteria

AJMR

Plants have potentials to be developed into many new drugs yet to be discovered because of the countless chemical compositions in them. The investigation is targeted at the antibacterial activity of sweet orange juice extract on some bacteria using ethanol and ethyl ethanoate solvent to extract juice. Ditch method was used for the sensitivity testing against Escherichia coliStaphylococcus aureusKlebsiella pneumoniae and Neisseria gonorrheae with a dilution factor of 10-10 for inoculation from pure culture of each selected bacteria. Disc method was used to test streptomycin, ciprofloxacin, gentamycin and penicillin G against test organisms as positive controls. There was no significant difference in the effect of different concentrations of the same extract on test organisms. However, there was a significant difference in the ethyl ethanoate and alcohol extracts. The ethyl ethanoate extract showed minimum inhibitory concentration at 300 mg/ml on E. coli (31.5 ± 0.5 mm); Ngonorrheae (21 ± 0.0 mm) at 200 mg/ml; Saureus (22 ± 0.0 mm) and Kpneumoniae (37 ± 3.0 mm) at 100 mg/ml; while ethanol extract at 100 mg/ml on E. coli (23.5 ± 1.5 mm) and Kpneumoniae (25 ± 5.0 mm);  N. gonorrheae (13.5 ± 1.0 mm) and S. aureus (12.5 ± 2.5 mm) at 300 mg/ml and 200 mg/ml respectively. The zones of inhibition exhibited by streptomycin ranges from Ngonorrheae (14-24 mm) E. coli; ciprofloxacin varies from 15- 21 mm on K. pneumoniae and S. aureus respectively. Gentamycin ranges from 14-20 mm on N. gonorrheae and S. aureus respectively; and penicillin G on N. gonorrheae (14 mm) and Saureus (28 mm). It can be concluded that sweet orange juice of ethyl ethanoate extract was more effective than the ethanol extract and the positive control.

Nigeria – Study Shows 76% Of Germs On Ready-To-Eat Fruits Are Multidrug-Resistant

Tribune Online

CONSUMPTION of fresh cut, ready-to-eat fruits (FCFs) processed and vended in open markets in Nigeria may constitute human health risks, causing food-borne diseases, due to microbial contamination, a study warns.

In the study, researchers had assessed pineapple and watermelon, which are among the commonest ready-to-eat fruits retailed and consumed regularly, including samples of fruit wash water and vendors’ hand, and found them heavily infested with different germs.

Research – Microbial Safety of Smoothie Drinks from Fresh Bars Collected in Slovakia

MDPI

Among the many consumers in Slovakia, smoothies are nowadays gaining popularity. Smoothie drinks are prepared from raw fruits and vegetables. Therefore, their microbiological safety depends on hygiene standards. The aim of this work was to monitor and quantify selected sensitive and antibiotic-resistant microorganisms present in collected smoothies. Twenty analyzed smoothie samples were collected from six food service establishments (fresh bars) in the capital city of Slovakia, Bratislava. Antibiotic-resistant bacteria were found in at least one of each fresh bar. Antibiotic-resistant coliform bacteria prevailed, especially in green smoothies or juices containing more vegetable ingredients. Resistance to ampicillin, ciprofloxacin, tetracycline, chloramphenicol, and gentamicin was observed in the case of coliform bacteria. More than half of the smoothie drink samples did not contain resistant enterococci. On the other hand, vancomycin-resistant enterococci were detected in 20% of samples. The most frequently isolated antibiotic-resistant strains belonged to the Enterobacter spp. or Klebsiella spp. genus. In the last part of the work, the pretreatment effect of smoothie components on the selected microorganisms’ counts in the final product was investigated. Washing ingredients with an aqueous solution of a biocide agent containing silver and hydrogen peroxide proved to be the most effective way to decrease bacterial counts. View Full-Text

Research – Microbial analysis and factors associated with contamination of ready-to-eat chili pepper sauce in Buea municipality, Cameroon

AJFS

Chili peppers sauce is a dietary complement largely consumed in Cameroon. It is consumed in a powder or wet (pepper sauce) form or directly introduced into cooked food. In this study, the microbiological quality of chili pepper sauce used as food complement in the Buea municipality was assessed. The study was an observational and cross-sectional study involving 70 chili pepper sauce samples from food vendors. The samples were cultured on Salmonella-Shigella agar, violet red bile agar, plate count agar and the colonies isolated were enumerated and identified using the Enterosystem 18R. Factors associated with microbial count were identified using a multiple linear regression model. Bacteria isolate from chili pepper sauce were mainly Entrobacter cloacae (31.57%), Citrobacter freundii (15.78%) and Klebsiella pneumonia (15.78%) and other Enterococcal speciesFactors associated with bacteria count were: age of the vendor, number of customers served, types of food and food storage conditions (covering, heating, type of storage containers). Chili pepper sauce used as food complement in Buea Municipality were contaminated with Enteric microorganisms and may represents a potential public health hazard to consumers. The presence of these microorganisms from chilli pepper sauce could result from poor handling.