ABSTRACT
This study aimed to evaluate the microbiological quality of coconut water sold from street carts equipped with cooling coils or refrigerated at bakeries in the Grande Vitória Region, Brazil. Additionally, it assessed the phenotypic and genotypic antimicrobial resistance profiles of isolated enterobacteria. The results indicated that coconut water sold at street carts had lower microbiological quality compared to refrigerated samples, as evidenced by significantly higher counts of mesophilic microorganisms. Using MALDI-TOF, the following opportunistic pathogens were identified: Citrobacter freundii, Enterobacter bugandensis, E. kobei, E. roggenkampii, Klebsiella pneumoniae, and Kluyvera ascorbata. Three isolates-E. bugandensis, K. pneumoniae, and K. ascorbata-were classified as multidrug-resistant (MDR). Widespread resistance to ß-lactams and cephalosporins was detected, and some isolates were resistant to quinolones, nitrofurans, and phosphonic acids. The gene blaCTX-M-2 was detected in C. freundii, E. bugandensis, E. kobei, and K. ascorbata. However, genes blaNDM, blaKPC, blaCMY-1, and blaCMY-2 were not detected in any isolate. The findings underscore the need to enhance good manufacturing practices in this sector to control the spread of antimicrobial resistance (AMR). To our knowledge, this is the first study documenting the presence of potentially pathogenic enterobacteria in coconut water samples and their associated phenotypic and genotypic AMR profiles.
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This study aimed to identify contamination sources in raw milk and cheese on small farms in Brazil by isolating Escherichia coli at various stages of milk production and cheese manufacturing. The study targeted EAEC, EIEC, ETEC, EPEC, STEC, and ExPEC pathotypes, characterizing isolates for the presence of virulence genes, phylogroups, antimicrobial susceptibility, and phylogenetic relationships using PFGE and MLST. The presence of antimicrobial resistance genes and serogroups was also determined. Three categories of E. coli were identified: pathogenic, commensal, and ceftriaxone-resistant (ESBL) strains. Pathogenic EPEC, STEC, and ExPEC isolates were detected in milk and cheese samples. Most isolates belonged to phylogroups A and B1 and were resistant to antimicrobials such as nalidixic acid, ampicillin, kanamycin, streptomycin, sulfisoxazole, and tetracycline. Genetic analysis revealed that E. coli with identical virulence genes were present at different stages within the same farm. The most frequently identified serogroup was O18, and MLST identified ST131 associated with pathogenic isolates. The study concluded that E. coli was present at multiple points in milk collection and cheese production, with significant phylogroups and high antimicrobial resistance. These findings highlight the public health risk posed by contamination in raw milk and fresh cheese, emphasizing the need to adopt hygienic practices to control these microorganisms.
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A contaminação de superfícies e do ar em cozinhas domésticas representa um grave problema de saúde pública, com microrganismos prejudiciais podendo se alojar em bancadas, utensílios e equipamentos, sendo transferidos através do contato com alimentos crus, resíduos alimentares e sujeira, além de serem dispersos pelo ar, onde os aerossóis podem se espalhar ou se depositar. O objetivo deste estudo foi avaliar a presença de Escherichia coli e Salmonella spp. em superfícies de contato em cozinhas domésticas, bem como a contagem total de microrganismos no ar. Foram coletadas amostras de superfície em seis cozinhas residenciais, utilizando swabs friccionados em maçanetas de geladeira, botões/alças/portas de eletrodomésticos (Airfryer, liquidificador, micro-ondas), portas de armários de mantimentos e gavetas de talheres utilizados no preparo de alimentos. Além disso, a amostragem passiva do ar foi realizada em três períodos de exposição, com os resultados quantificados em Unidades Formadoras de Colônias (UFC). Os resultados indicaram que 72% das amostras estavam contaminadas com bactérias entéricas, sendo 8,3% especificamente contaminadas com Salmonella spp. e E. coli, principalmente na gaveta de talheres e na porta da geladeira. Ficou evidente a importância da limpeza e desinfecção adequadas dessas superfícies para prevenir a contaminação e garantir a segurança dos alimentos. Observou-se também que as superfícies menos higienizadas apresentavam maior contaminação. Ademais, a legislação local em vigor destaca a qualidade microbiológica do ar, considerada de péssima qualidade neste estudo em comparação com os padrões da literatura. Para prevenir a contaminação de superfícies de contato em cozinhas domésticas, é crucial adotar práticas simples, como lavar as mãos com frequência, manter a limpeza e desinfecção regular das superfícies, separar utensílios e equipamentos usados para alimentos crus e cozidos, e armazenar alimentos adequadamente.(AU)
Contamination of surfaces and air in household kitchens poses a significant public health concern, as harmful microorganisms can adhere to countertops, utensils, and equipment, and can be transferred through contact with raw food, food waste, and dirt, as well as dispersed through the air, where aerosols can spread or settle. The aim of this study was to assess the presence of Escherichia coli and Salmonella spp. on contact surfaces in domestic kitchens, along with the total count of microorganisms in the air. Surface samples were collected from six residential kitchens, using swabs rubbed on refrigerator handles, buttons/handles/doors of household appliances (Airfryer, blender, microwave), pantry cabinet doors, and cutlery drawers used in food preparation. Additionally, passive air sampling was conducted in three exposure periods, with results quantified in Colony Forming Units (CFU). The findings revealed that 72% of the samples were contaminated with enteric bacteria, with 8.3% specifically contaminated with Salmonella spp. and E. coli, predominantly in the cutlery drawer and on the refrigerator door. The importance of proper cleaning and disinfection of these surfaces to prevent contamination and ensure food safety became apparent. It was also noted that less sanitized surfaces exhibited greater contamination. Furthermore, current local legislation emphasizes the microbiological quality of the air, which was deemed poor in this study compared to literature standards. To mitigate contamination of touch surfaces in home kitchens, it is imperative to adopt straightforward practices such as frequent handwashing, regular cleaning and disinfection of surfaces, segregation of utensils and equipment used for raw and cooked foods, and appropriate food storage.(AU)
Subject(s)
Air Quality Control , Food Microbiology , Food SupplyABSTRACT
This study aimed to analyze Escherichia coli from marketed meat samples in Peru. Sixty-six E. coli isolates were recovered from 21 meat samples (14 chicken, 7 beef), and antimicrobial resistance levels and the presence of mechanisms of antibiotic resistance, as well as clonal relationships and phylogeny of colistin-resistant isolates, were established. High levels of antimicrobial resistance were detected, with 93.9% of isolates being multi-drug resistant (MDR) and 76.2% of samples possessing colistin-resistant E. coli; of these, 6 samples from 6 chicken samples presenting mcr-1-producer E. coli. Colistin-resistant isolates were classified into 22 clonal groups, while phylogroup A (15 isolates) was the most common. Extended-spectrum ß-lactamase- and pAmpC-producing E. coli were found in 18 and 8 samples respectively, with blaCTX-M-55 (28 isolates; 16 samples) and blaCIT (8 isolates; 7 samples) being the most common of each type. Additionally, blaCTX-M-15, blaCTX-M-65, blaSHV-27, blaOXA-5/10-like, blaDHA, blaEBC and narrow-spectrum blaTEM were detected. In addition, 5 blaCTX-M remained unidentified, and no sought ESBL-encoding gene was detected in other 6 ESBL-producer isolates. The tetA, tetE and tetX genes were found in tigecycline-resistant isolates. This study highlights the presence of MDR E. coli in Peruvian food-chain. The high relevance of CTX-M-55, the dissemination through the food-chain of pAmpC, as well as the high frequency of unrelated colistin-resistant isolates is reported.
ABSTRACT
CONTEXT: The safety of enteral formulas is important to restore and maintain the health of patients. OBJECTIVE: A systematic review of the literature was conducted to assess the microbiological contamination present in enteral tube feeding prepared in hospitals and/or at home. DATA SOURCES: A systematic search was conducted of the Medline, Scopus, BVS, CAPES/MEC, Embase, Science Direct, and SciELO databases and gray literature. DATA EXTRACTION: Eligible studies that analyzed the contamination of enteral formulas manipulated in hospitals and/or at home were selected; a quality assessment tool was used. DATA ANALYSIS: Twenty-three studies evaluated 1099 enteral formulations. Of these, 44.67% of enteral formulas (n = 491) exceeded the acceptable bacterial count. Samples of homemade enteral formulation preparations (86.03%; n = 191) had the highest bacterial counts, followed by mixed preparations (79.72%; n = 59), and commercial formulas (30.01%; n = 241). The number of samples of enteral formulations that exceeded the bacterial count at home was 70.79% (n = 160 at the hospital was 37.91% (n = 331). Total coliforms (82.68%; n = 406) and mesophilic aerobes (79.22%; n = 389) were the most common microorganisms. Samples with bacterial pathogens were also identified, with Bacillus cereus (4.07%; n = 20) and Listeria monocytogenes (3.66%; n = 18) being the most prevalent. CONCLUSIONS: A high number of samples of enteral formulations exceeded the bacterial count, but the risk to patient's health when consuming enteral tube feeding prepared in hospitals or at home may be low. This is because the bacteria present in the samples are not considered potential causes of disease but rather indicators of hygiene conditions. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42022367573.
ABSTRACT
Salmonella is present in the poultry production chain and is a major challenge in terms of food safety and animal health. The early Salmonella detection is one of the main tools to control and prevent the transmission of this pathogen. Microbiological isolation and serotyping to identify and differentiate Salmonella serovars are laborious processes, time-consuming, and expensive. Therefore, molecular diagnostic methods can be rapid and efficient alternatives to the detection of this pathogen. Thus, the aim herein was to standardize and evaluate the use of loop-mediated isothermal amplification (LAMP) in comparison with real-time PCR (qPCR) for detection of Salmonella associated with a multiplex qPCR for simultaneous identification and differentiation of S. Enteritidis, S. Typhimurium, S. Pullorum, and S. Gallinarum. The LAMP, qPCR, and multiplex qPCR assays were comparable in specificity. The three techniques were evaluated for specificity for 16 different serovars of Salmonella and for 37 strains of the serovars of interest. The limit of detection and the efficiency of the LAMP, qPCR, and multiplex qPCR reactions were determined. The techniques were applied to 33 samples of chicken carcasses and compared to the results of conventional microbiology for validation. As results, LAMP was specific in the detection of different Salmonella serovars but presented lower limit of detection ranging from 101 to 104 CFU/reaction. In comparison, qPCR could detect less cells (100 to 102 CFU/reaction), reaching equal specificity and better repeatability in the assays. The qPCR multiplexing for identification of the different serovars also showed good specificity, with the detection threshold between entre 101 and 102 CFU/reaction. The results obtained in the analyses on poultry carcasses suggested a correspondence between the results obtained in molecular methods and in conventional microbiology. Thus, the proposed assays are promising for the diagnosis of Salmonella in poultry carcasses, already proved to be faster and more efficient than conventional diagnostics techniques, being of great interest for poultry production, animal, and public health.
Subject(s)
Poultry , Salmonella , Animals , Poultry/microbiology , Serogroup , Food Safety/methods , Chickens/microbiology , Sensitivity and SpecificityABSTRACT
El comercio ambulante de alimentos listos para el consumo ha crecido exponencialmente a nivel mundial. Sin embargo, la falta de condiciones óptimas de preparación y expendio de estos alimentos pueden afectar su inocuidad. El objetivo de este estudio fue evaluar la calidad microbiológica de 19 tipos de alimentos (n= 417), con y sin tratamiento térmico, expendidos en espacios públicos en Cuenca, Ecuador. Según el grupo de alimentos, se analizaron aerobios mesófilos, coliformes/Escherichia coli, mohos y levaduras, Staphylococcus aureus, Salmonella, Listeria spp., Clostridium perfringes y Vibrio parahaemolyticus. Para la identificación y recuento de los microorganismos se aplicaron normativas nacionales y, en casos de ausencia, se adoptaron normas de otros países. Como resultado, el 55,4% de las muestras se consideraron no aptas para el consumo. S. aureus fue el microorganismo patógeno presuntivo de mayor prevalencia (81,7%). El incumplimiento de las normativas fue significativamente mayor entre los alimentos sin tratamiento térmico (54,1%) en comparación con aquellos térmicamente tratados (24%) y los que combinan ingredientes con y sin tratamiento (21,9%) (p<0,001). Se destaca el alto porcentaje de incumplimiento de alimentos sin tratamiento térmico que son manipulados en su preparación, como los jugos. Además, se observó que el tratamiento térmico no garantizó la inocuidad, sugiriendo una posible recontaminación del alimento luego de su preparación hasta su expendio y consumo, por medios ambientales y/o adición de otros ingredientes contaminados. Este estudio recalca la necesidad de acciones concretas con este sector, basados principalmente en capacitación, infraestructura e inclusión, para garantizar la salud de los consumidores.
Street-vending trade in ready-to-eat foods has grown exponentially, worldwide. However, the lack of optimal conditions for the preparation and sale of these foods can affect their safety. The objective of this study was to evaluate the microbiological quality of 19 types of foods (n= 417), with and without heat treatment, sold in public spaces in Cuenca, Ecuador. According to the food group, mesophilic aerobes, coliforms/Escherichia coli, molds and yeasts, Staphylococcus aureus, Salmonella, Listeria spp., Clostridium perfringens, and Vibrio parahaemolyticus were examined. For microorganisms identification and counting, national regulations were applied and, in cases of absence, regulations from other countries were adopted. As a result, 55,4% of the samples were considered inadequate for consumption. S. aureus was the most prevalent presumptive pathogenic microorganism (81.7%). Non-compliance with regulations was significantly higher among foods without heat treatment (54.1%) compared to those heat treated (24%) and those that combine ingredients with and without treatment (21.9%) (p<0.001). The high percentage of non-compliance with foods without heat treatment that is handled for preparation, such as juices, stands out. In addition, it was observed that the heat treatment did not guarantee safety, suggesting possible food recontamination after preparation until sale and consumption, due to environmental means and/or the addition of other contaminated ingredients. This study emphasizes the need for concrete actions in this sector, mainly based on training, infrastructure, and inclusion, to guarantee consumers' health.
ABSTRACT
Phenolic compounds are natural substances that are produced through the secondary metabolism of plants, fungi, and bacteria, in addition to being produced by chemical synthesis. These compounds have anti-inflammatory, antioxidant, and antimicrobial properties, among others. In this way, Brazil represents one of the most promising countries regarding phenolic compounds since it has a heterogeneous flora, with the presence of six distinct biomes (Cerrado, Amazon, Atlantic Forest, Caatinga, Pantanal, and Pampa). Recently, several studies have pointed to an era of antimicrobial resistance due to the unrestricted and large-scale use of antibiotics, which led to the emergence of some survival mechanisms of bacteria to these compounds. Therefore, the use of natural substances with antimicrobial action can help combat these resistant pathogens and represent a natural alternative that may be useful in animal nutrition for direct application in food and can be used in human nutrition to promote health. Therefore, this study aimed to (i) evaluate the phenolic compounds with antimicrobial properties isolated from plants present in Brazil, (ii) discuss the compounds across different classes (flavonoids, xanthones, coumarins, phenolic acids, and others), and (iii) address the structure-activity relationship of phenolic compounds that lead to antimicrobial action.
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The aimed of the study was to evaluate the quality of raw milk from some suppliers in rural and urban areas and to test the hypothesis that it is unsafe for direct consumption. The study was conducted with suppliers in rural and urban areas in Presidente Médici municipality, Rondônia state. The method of the Ministério da Agricultura, Pecuária e Abastecimento (MAPA), was used, which consists of titrating a portion of the sample with a sodium hydroxide solution of known concentration, using phenolphthalein as an indicator. According to Brazilian legislation and literature, stability of Alizarol, foreign substances, Chloride, Hypochlorite, Hydrogen Peroxide and Colostrum were analyzed. Microbiological analysis, standard plate count (SPC) and quantification of thermotolerant coliforms were also performed using the most probable number (MPN) technique. Values above the limits established by legislation were found, mainly for temperature and titleable acidity, in addition to stability results against Alizarol and the presence of colostrum. There were high microbial contents with regard to SPC, and, in this case, the presence of pathogenic microorganisms cannot be disregarded. The presence of thermotolerant coliforms may indicate probable contact of milk with feces. Therefore, it is considered that the samples analyzed here are not safe for ingestion in the raw form.(AU)
O objetivo do estudo foi avaliar a qualidade do leite cru de alguns fornecedores da zona rural e urbana e tes-tar a hipótese de que não são seguros para o consumo direto. O estudo foi conduzido em fornecedores da zona rural e urbana do município de Presidente Médici, estado de Rondônia. Empregou-se o método do Ministério da Agricultura Pecuária e Abastecimento (MAPA), que consiste na titulação de uma porção da amostra por uma solução hidróxido de sódio de concentração conhecida, utilizando como indicador a fenolftaleína. Conforme a legislação brasileira e a lite-ratura, foram analisados estabilidade do Alizarol, substâncias estranhas, Cloreto, Hipoclorito, peróxido de Hidrogênio e Colostro. Foram realizadas também análises microbiológicas, contagem Padrão em Placa (CPP) e quantificação dos coliformes termotolerantes através da técnica do número mais provável (NMP). Foram encontrados valores acima dos limites estabelecidos pela legislação, principalmente para temperatura e acidez titulável, além dos resultados de estabili-dade frente ao Alizarol e da presença de colostro. Houve altos teores microbianos no que se refere à CPP, e, nesse caso, a presença de microrganismos patogênicos não pode ser desconsiderada. A presença de coliformes termotolerantes pode indicar provável contato do leite com fezes. Portanto, considera-se que as amostras aqui analisadas não são seguras para ingestão na forma crua.(AU)
Subject(s)
Animals , Cattle , Milk/microbiology , Milk/chemistry , Chemical Phenomena , BrazilABSTRACT
Abstract Objectives: microbiological quality of raw human milk (HM) from donors at the HMB (Human Milk Bank) of Santa Casa de Misericórdia de Ouro Preto was evaluated. Methods: the microbiological quality of milk from each of 10 donors in triplicate (30 samples) was evaluated by enumeration of Staphylococcus aureus and total aerobic mesophiles (surface plating) and total and thermotolerant coliforms (Most Probable Number - MPN). A questionnaire and a checklist were applied after the end of sample collection to verify the compliance of milk extraction and storage procedures by the donors. Results: inadequacies in the procedures for expression and storage of donated HM were observed. The presence of all microorganisms studied were verified in the milk of all donors, and in some cases exceeded the safety limits. The checklist indicated that some necessary hygienic-sanitary procedures were not carefully performed, making it important to properly guide the donors. Conclusions: this study points to an unfavorable scenario for the safety and quality of donated HM, and it is important to encourage further studies to be conducted so that the Brazilian network of HMB adopts stricter criteria for instructions on procedures and support for HM donors.
Resumo Objetivos: avaliou-se a qualidade microbiológica do leite humano (LH) cru de doadoras do Banco de Leite Humano (BLH) da Santa Casa de Misericórdia de Ouro Preto. Métodos: a qualidade microbiológica do leite de cada uma das 10 doadoras em triplicata (30 amostras) foi avaliada por meio da enumeração de Staphylococcus aureus e mesóflos aeróbios totais (plaqueamento em superfície) e coliformes totais e termotolerantes (Número Mais Provável -NMP). Para verificar a conformidade dos procedimentos de extração e armazenamento do leite pelas doadoras, aplicou-se um questionário e um checklist após o término da coleta das amostras. Resultados: observou-se inadequações nos procedimentos de expressão e armazenamento do LH doado. A presença de todos os microrganismos estudados foram verificados no leite de todas as doadoras e, em alguns casos, excedeu os limites de segurança. O checklist indicou que alguns procedimentos higiênico-sanitários necessários não foram realizados criteriosamente, tornando importante orientar adequadamente as doadoras. Conclusões: este estudo aponta um cenário desfavorável para a segurança e a qualidade do LH doado, sendo importante incentivar mais estudos a serem realizados para que a rede brasileira de BLH adote critérios mais rigorosos de instruções sobre procedimentos e suporte para doadoras de LH.
Subject(s)
Humans , Female , Pregnancy , Quality Control , Food Quality , Milk Banks/standards , Breast Milk Expression/methods , Food Microbiology , Milk, Human/microbiology , BrazilABSTRACT
This study aimed to evaluate and model the antimicrobial action of different concentrations of Croton blanchetianus essential oil (CBEO) on the behavior of six bacterial species in vitro. CBEO extraction was performed by hydrodistillation and characterized by CG-MS. CBEO solutions in culture media were tested at 0.90, 1.80, 2.71, and 4.51 mg of CBEO/mL, against foodborne bacteria: pathogenic bacteria (Staphylococcus aureus, Listeria monocytogenes and Salmonella Enteritidis at 35 °C), a non-pathogenic Escherichia coli (at 35 °C), and spoilage bacteria (Weissella viridescens and Leuconostoc mesenteroides at 30 °C). The CBEO major compounds were eucalyptol, α-pinene, sativene, E-caryophyllene, bicyclogermacrene, and spatulenol. Baranyi and Roberts (growth) and Weibull (inactivation) primary models, along with power and hyperbolic secondary models, were able to describe the data. CBEO inactivated L. monocytogenes, S. aureus, L. mesenteroides and W. viridescens at all applied concentrations. CBEO did not inactivate S. Enteritidis and E. coli, but their growth rates were reduced.
Subject(s)
Croton , Listeria monocytogenes , Oils, Volatile , Anti-Bacterial Agents/pharmacology , Croton Oil/pharmacology , Escherichia coli , Oils, Volatile/pharmacology , Staphylococcus aureusABSTRACT
Foodborne pathogens represent a significant cause of negative impacts on human health and the economy worldwide. Unfortunately, information about epidemiological insights in Latin American countries is scarce. The consumption of ready-to-eat street food in Ecuador is extensive, and information about the presence of foodborne pathogens, their virulence factors, and antimicrobial resistance is negligible. This data includes the occurrence, phenotypic antibiotic resistance profiles, and antibiotic resistance genes of Enterobacterales isolated from ready-to-eat street food in Ambato, central Ecuador during 2020 and 2021. The most common genera detected were Escherichia coli, Klebsiella spp., and Cronobacter spp. Agar disk diffusion assays were performed to determine their phenotypic resistance. The presence of antibiotic resistance genes conferring resistance against colistin, ß-Lactams, aminoglycosides, tetracyclines, sulfonamides, fluoroquinolones, and amphenicols was detected via polymerase chain reaction (PCR) amplification.
Subject(s)
Anti-Bacterial Agents , Colistin , Anti-Bacterial Agents/pharmacology , Ecuador , Escherichia coli , Humans , Microbial Sensitivity TestsABSTRACT
Pathogens such as Salmonella can be difficult to control in low-moisture food (LMF) processing plants and because of this its presence especially in biofilm mode should be prevented in such an environment. This study evaluated the capacity of Salmonellastrains isolated from the peanut supply chain (S. Muenster, S. Miami, S. Glostrup, S. Javiana, S. Oranienburg and S. Yoruba) to form biofilm as well as their resistance to sanitizers (sodium hypochlorite, peracetic acid, quaternary ammonium, alkaline chlorinated solution and biguanide). Regarding biofilm formation, there was no significant difference (p > 0.05) among the strains tested singly on AISI 304 stainless steel (SS) and polypropylene (PP) coupons at the same temperature. However, a difference (p < 0.05) between the temperatures was noted in the first hours of incubation. The sessile cells reached counts between 3 and 4 log CFU/cm2 at 25 °C whereas>5 log CFU/cm2 was observed at 37 °C after 8 h. From 24 h the counts were above 6 log CFU/cm2 for both temperatures. Nevertheless, the SEM images of the 6-strain pool showed the highest density of adhered cells after 48 h at 25 °C and 24 h at 37 °C on PP, and after 48 h at both temperatures on SS. Peracetic acid (300 mg/L) had the shortest action time against 24-h biofilm on SS and PP, with sessile cell counts below the limit of detection (0.59 log CFU/cm2) after 3 min. For 48-h and 96-h biofilm, sodium hypochlorite (200 mg/L) decreased>4 log CFU/cm2 within 5 min. Quaternary ammonium (350 mg/L) and chlorinated alkaline detergent (200 mg/L) showed intermediate performances. Only biguanide (800 mg/L) did not reduce the biofilm counts to below the limit of detection in any of the conditions evaluated. The results indicated high biofilm formation ability of the Salmonella strains isolated from the peanut supply chain. Nevertheless, in general the biofilms were sensitive to most sanitizers within 15 min of treatment. This was the first study which evaluated biofilm formation by Salmonella isolated from the peanut supply chain. Data obtained here will contribute to optimize the hygiene practices in LMF manufacturing plants.
Subject(s)
Arachis , Disinfectants , Biofilms , Colony Count, Microbial , Disinfectants/pharmacology , SalmonellaABSTRACT
Several non-dairy probiotic beverages are already available to consumers and have been considered suitable carriers for probiotic bacteria. This study aimed to investigate the effect of Lactiplantibacillus plantarum CCMA 0743 in single and co-culture on the volatile compounds and sensory profiles of fermented passion fruit juice. The viability of strains inoculated in juice and MRS matrices was evaluated in a simulated gastrointestinal condition. The bacterial viability after 28 days of refrigerated storage of the juices was also evaluated. L. plantarum CCMA 0743 showed high viability (6.18 Log CFU/mL) after passage throughout simulated digestion in the passion fruit juice matrix. Both juices maintained high probiotic counts (>8.0 Log CFU/mL) during storage. Also, the yellow color was stable after 28 days of storage. Volatile compounds of passion fruit juices were modified after the fermentation process, such as ketones and alcohol formation degradation. The sensory profile of passion fruit juice was modified by single and co-culture fermentations. The fermented samples were mainly correlated with the terminologies "salty, acidic and bitter tastes" and "sweetener aftertaste". Overall, passion fruit juice proved to be an adequate food matrix to deliver the evaluated strains. However, individual strains or strain-strain interactions with the food matrix affect the fermented product, demonstrating that strain and matrices evaluations are essential for developing novel products with acceptable characteristics.
Subject(s)
Fruit and Vegetable Juices , Probiotics , Beverages/microbiology , Fermentation , Odorants/analysis , Probiotics/metabolismABSTRACT
Hand hygiene interventions are critical for reducing farmworker hand contamination and preventing the spread of produce-associated illness. Hand hygiene effectiveness may be produce-commodity specific, which could influence implementation strategies. This study's goal was to determine if produce commodity influences the ability of handwashing with soap and water or two-step alcohol-based hand sanitizer (ABHS) interventions to reduce soil and bacteria on farmworker hands. Farmworkers (n = 326) harvested produce (cantaloupe, jalapeño, and tomato) for 30 to 90 minutes before engaging in handwashing, two-step ABHS (jalapeño and cantaloupe), or no hand hygiene. Hands were rinsed to measure amounts of soil (absorbance at 600 nm) and indicator bacteria (coliforms, Enterococcus sp., generic Escherichia coli, and Bacteroidales universal [AllBac] and human-specific [BFD] 16S rRNA gene markers). Without hand hygiene, bacterial concentrations (0.88 to 5.1 log10 CFU/hand) on hands significantly differed by the produce commodity harvested. Moderate significant correlations (ρ = -0.41 to 0.56) between soil load and bacterial concentrations were observed. There were significant produce-commodity-specific differences in the ability of handwashing and two-step ABHS interventions to reduce soil (P < 0.0001), coliforms (P = 0.002), and Enterococcus sp. (P = 0.003), but not the Bacteroidales markers AllBac (P = 0.4) or BFD (P = 0.3). Contamination on hands of farmworkers who harvested cantaloupe was more difficult to remove. Overall, we found that a two-step ABHS intervention was similar to handwashing with soap and water at reducing bacteria on farmworker hands. In summary, produce commodity type should be considered when developing hand hygiene interventions on farms.IMPORTANCE This study demonstrated that the type of produce commodity handled influences the ability of handwashing with soap and water or a two-step alcohol-based hand sanitizer (ABHS) intervention to reduce soil and bacterial hand contamination. Handwashing with soap and water, as recommended by the FDA's Produce Safety Rule, when tested in three agricultural environments, does not always reduce bacterial loads. Consistent with past results, we found that the two-step ABHS method performed similarly to handwashing with soap and water but also does not always reduce bacterial loads in these contexts. Given the ease of use of the two-step ABHS method, which may increase compliance, the two-step ABHS method should be further evaluated and possibly considered for implementation in the agricultural environment. Taken together, these results provide important information on hand hygiene effectiveness in three agricultural contexts.
Subject(s)
Bacterial Load/drug effects , Crop Production , Crops, Agricultural/classification , Hand Disinfection/instrumentation , Hand Sanitizers/administration & dosage , Hand/microbiology , Soil , Capsicum/growth & development , Cucumis melo/growth & development , Ethanol/chemistry , Farmers , Hand Sanitizers/chemistry , Humans , Solanum lycopersicum/growth & development , MexicoABSTRACT
A ausência de Boas Práticas de Fabricação durante a colheita, processamento e manuseio da pimenta-do-reino pode acarretar a contaminação do produto com sujidades microscópicas e microrganismos. Foram analisadas 227 amostras de pimenta-do-reino, comercializadas em Minas Gerais, coletadas entre 2008 e 2018, quanto à presença de fragmentos de pelo de roedor e de insetos, coliformes a 45°C ou Escherichia coli e Salmonella spp. Para verificar se havia correlação entre os contaminantes, foi empregado método estatístico de regressão linear múltipla. As análises microscópicas evidenciaram presença de fragmentos de pelo de roedor e de insetos em 26,0% e 30,5% das amostras, respectivamente, em valores superiores ao limite tolerado pela RDC 14/2014. Quanto às análises microbiológicas, 10% das amostras apresentaram coliformes a 45°C ou E. coli acima dos limites tolerados pela RDC 12/2001 e em 8,8% das amostras foi detectada presença de Salmonella spp. A avaliação estatística mostrou que houve correlação entre presença de fragmentos de insetos e de pelos de roedor e a contaminação por Salmonella spp. em pimenta-do-reino. Os resultados demonstraram a importância das análises microscópica e microbiológica simultaneamente para detecção dos contaminantes presentes bem como das possíveis relações existentes entre eles e a melhor compreensão dos fatores que favorecem as contaminações.(AU)
The absence of Good Manufacturing Practices during harvesting, processing and handling of black pepper can lead to contamination of the product with microscopic dirt and microrganisms. Two hundred and twenty seven black pepper samples, commercialized in Minas Gerais, collected between 2008 and 2018, were analyzed for the presence of rodent and insect fragments, coliforms at 45°C or Escherichia coli and Salmonella spp. To verify whether there was a correlation between the contaminants, a statistical method of multiple linear regression was used. Microscopic analysis showed the presence of rodent and insect fragments in 26.0% and 30.5% of the samples, respectively, in values above the limit tolerated by RDC14/2014. As for the microbiological analysis, 10% of the samples presented coliforms at 45°C or E.coli above the limits tolerated by the RDC 12/2001 and in 8.8% of the samples Salmonella spp. were detected. The statistical evaluation showed that there was a relationship between the presence of insect fragments and rodent hair and contamination by Salmonella spp. in black pepper. The results demonstrated the importance of simultaneous microscopic and microbiological analysis to detect the contaminants present, as well as the possible relationships between them and better understanding of the factors that favor contamination.(AU)
Subject(s)
Piper nigrum/microbiology , Food Microbiology , Quality Control , Food Contamination/analysis , Escherichia coli , Correlation of Data , Salmonella , Good Manufacturing PracticesABSTRACT
A ausência de Boas Práticas de Fabricação durante a colheita, processamento e manuseio da pimenta-do-reino pode acarretar a contaminação do produto com sujidades microscópicas e microrganismos. Foram analisadas 227 amostras de pimenta-do-reino, comercializadas em Minas Gerais, coletadas entre 2008 e 2018, quanto à presença de fragmentos de pelo de roedor e de insetos, coliformes a 45°C ou Escherichia coli e Salmonella spp. Para verificar se havia correlação entre os contaminantes, foi empregado método estatístico de regressão linear múltipla. As análises microscópicas evidenciaram presença de fragmentos de pelo de roedor e de insetos em 26,0% e 30,5% das amostras, respectivamente, em valores superiores ao limite tolerado pela RDC 14/2014. Quanto às análises microbiológicas, 10% das amostras apresentaram coliformes a 45°C ou E. coli acima dos limites tolerados pela RDC 12/2001 e em 8,8% das amostras foi detectada presença de Salmonella spp. A avaliação estatística mostrou que houve correlação entre presença de fragmentos de insetos e de pelos de roedor e a contaminação por Salmonella spp. em pimenta-do-reino. Os resultados demonstraram a importância das análises microscópica e microbiológica simultaneamente para detecção dos contaminantes presentes bem como das possíveis relações existentes entre eles e a melhor compreensão dos fatores que favorecem as contaminações.
The absence of Good Manufacturing Practices during harvesting, processing and handling of black pepper can lead to contamination of the product with microscopic dirt and microrganisms. Two hundred and twenty seven black pepper samples, commercialized in Minas Gerais, collected between 2008 and 2018, were analyzed for the presence of rodent and insect fragments, coliforms at 45°C or Escherichia coli and Salmonella spp. To verify whether there was a correlation between the contaminants, a statistical method of multiple linear regression was used. Microscopic analysis showed the presence of rodent and insect fragments in 26.0% and 30.5% of the samples, respectively, in values above the limit tolerated by RDC14/2014. As for the microbiological analysis, 10% of the samples presented coliforms at 45°C or E.coli above the limits tolerated by the RDC 12/2001 and in 8.8% of the samples Salmonella spp. were detected. The statistical evaluation showed that there was a relationship between the presence of insect fragments and rodent hair and contamination by Salmonella spp. in black pepper. The results demonstrated the importance of simultaneous microscopic and microbiological analysis to detect the contaminants present, as well as the possible relationships between them and better understanding of the factors that favor contamination.
Subject(s)
Food Contamination/analysis , Quality Control , Escherichia coli , Food Microbiology , Piper nigrum/microbiology , Good Manufacturing Practices , Correlation of Data , SalmonellaABSTRACT
Use of fungicides is a common practice as a postharvest treatment to control fruit decay. Nowadays, environment friendly technologies, such as heat treatments, are viable replacements. This study evaluated the effects of post-harvest heat treatments (traditional and microwave-assisted) on mandarins intentionally inoculated with Penicillium digitatum. For the studied heat treatments, the target temperature was 50 °C, which was held for 2.5 min. After heating, mandarins were cooled and stored at 25 °C for 13 days. MW treatments effectively prevented mold growth during storage, while HW only delayed it. Control mandarins (without treatment) showed the highest significant weight loss. Neither thermal treatment nor storage affected fruit juice pH (p > 0.05). Treated mandarins had a significantly lower vitamin C content than control fruits throughout storage, and all mandarins lost firmness by the 13th day (p < 0.05). Control and MW-treated mandarins had lower citric acid content; however, they retained color, total soluble solids (TSS) and had a higher maturity index. While HW mandarins did not have changes in citric acid content, they had higher TSS, and lower maturity index. MW-assisted treatments were effective at inactivating molds and helped retain some nutritional and physical-chemical characteristics of mandarins. However, juice of MW-treated mandarins was not preferred by judges in the sensory tests, the juice was rated lower than that obtained from the other treatment. Postharvest heat treatments may constitute a helpful application to control mandarin' fungal decay.
ABSTRACT
LEE-negative Shiga toxin-producing Escherichia coli (STEC) strains are important cause of infection in humans and they should be included in the public health surveillance systems. Some isolates have been associated with haemolytic uremic syndrome (HUS) but the mechanisms of pathogenicity are is a field continuos broadening of knowledge. The IrgA homologue adhesin (Iha), encoded by iha, is an adherence-conferring protein and also a siderophore receptor distributed among LEE-negative STEC strains. This study reports the presence of different subtypes of iha in LEE-negative STEC strains. We used genomic analyses to design PCR assays for detecting each of the different iha subtypes and also, all the subtypes simultaneously. LEE-negative STEC strains were designed and different localizations of this gene in STEC subgroups were examinated. Genomic analysis detected iha in a high percentage of LEE-negative STEC strains. These strains generally carried iha sequences similar to those harbored by the Locus of Adhesion and Autoaggregation (LAA) or by the plasmid pO113. Besides, almost half of the strains carried both subtypes. Similar results were observed by PCR, detecting iha LAA in 87% of the strains (117/135) and iha pO113 in 32% of strains (43/135). Thus, we designed PCR assays that allow rapid detection of iha subtypes harbored by LEE-negative strains. These results highlight the need to investigate the individual and orchestrated role of virulence genes that determine the STEC capacity of causing serious disease, which would allow for identification of target candidates to develop therapies against HUS.