RESUMO

Introducción: El apego a las normas oficiales sanitarias sirve para prevenir riesgos a la salud humana. Objetivo: Evaluar la calidad higiénico-sanitaria y las buenas prácticas de manufactura de alimentos (BPMA) de un comedor estudiantil en México. Materiales y métodos: Estudio cuasiexperimental y analítico. Durante el año 2020, se realizaron pruebas bacteriológicas a muestras de alimentos, agua, superficies y manos de manipuladores de alimentos, además de también evaluar las BPMA. Conforme a las normas oficiales sanitarias vigentes en México, se recolectaron 57 muestras, se aislaron y se lograron identificar patógenos. Las BPMA se valoraron en 20 manipuladores, antes y después de una intervención educativa de 10 semanas de duración y se utilizó la prueba t con α=0,05. Resultados: Más del 50 % de las muestras resultaron con microorganismos de riesgo para la salud, como Escherichia coli, Staphylococcus aureus, Pseudomonas, Acinetobacter baumanni complex y Coliformes totales. Las evaluaciones, antes y después de la intervención educativa de BPMA, evidenciaron diferencias estadísticamente significativas en el número de aciertos (p≤0,05). Conclusiones: La calidad higiénico-sanitaria del comedor analizado representó riesgo para la salud de los estudiantes, lo cual tuvo relación con la primera evaluación de las BPMA entre los manipuladores, las cuales mejoraron después de la intervención.

Introduction: Adherence to official health standards is essential to prevent human health risks. Objective: To assess the hygienic-sanitary quality and good food manufacturing practices (GMP) in a student cafeteria in Mexico. Materials and methods: Quasi-experimental and analytical study. During 2020, bacteriological tests were carried out on samples taken from food, water, surfaces, and hands of food handlers. In addition, GMP were evaluated. Based on the current Mexican official health regulations, 57 samples were collected to isolate and identify pathogens. GMP were assessed in 20 food handlers before and after a 10-week training intervention and a test was used with α=0.05. Results: More than 50% of samples were found to have microorganisms associated with health risks, including Escherichia coli, Staphylococcus aureus, Pseudomonas, Acinetobacter baumanni complex and total Coliforms. The analyses before and after the GMP training intervention showed statistically significant differences in terms of the presence of these pathogens (p≤0.05). Conclusions: The hygienic-sanitary quality of the analyzed cafeteria turned out to be a risk for the health of students, which was related to the first assessment of GMP in food handlers. Consequently, the results improved after the intervention.

Introdução: A adesão às normas sanitárias oficiais serve para prevenir riscos à saúde humana. Objetivo: Avaliar a qualidade higiênico-sanitária e as boas práticas de fabricação de alimentos (BPMA) de um refeitorio estudantil no México. Materiais e métodos: Estudo quase-experimental e analítico. Durante 2020, foram realizados testes bacteriológicos em amostras de alimentos, água, superfícies e mãos de manipuladores de alimentos, além de avaliação de BPMA. De acordo com as normas sanitárias oficiais em vigor no México, foram coletadas e isoladas 57 amostras e identificados patógenos. Os BPMA foram avaliados em 20 manipuladores, antes e após uma intervenção educativa de 10 semanas e foi utilizado o teste t com α=0,05. Resultados: Verificou-se que mais de 50% das amostras continham microrganismos de risco à saúde, como Escherichia coli, Staphylococcus aureus, Pseudomonas, complexo Acinetobacter baumanni e Coliformes totais. As avaliações, antes e após a intervenção educativa BPMA, apresentaram diferenças estatisticamente significativas no número de acertos (p≤0,05). Conclusões: A qualidade higiênico-sanitária do refeitório analisado representou um risco para a saúde dos alunos, o que esteve relacionado à primeira avaliação do BPMA entre os manipuladores, que melhorou após a intervenção.

Assuntos

RESUMO

La contaminación de las áreas de preparación al entrar en contacto con los alimentos crudos o cocinados, es por esto que una de las principales causas de la contaminación de las superficies inertes es la inadecuada manipulación de los alimentos a la hora de ser preparados. Con el objetivo de controlar la aplicación de normas de higiene en las áreas de preparación y consumo de alimentos mediante análisis microbiológicos para disminuir los riesgos de contaminación alimentaria. Esta investigación es de carácter descriptivo, en la cual se realizó una inspección visual del establecimiento con el propósito de evaluar las condiciones higiénicas sanitarias, mediante la aplicación de la Guía Técnica para el Análisis Microbiológico de Superficies en contacto con Alimentos y Bebidas. Para el análisis microbiológico de las muestras se emplearon las técnicas de inoculación, método de estriado, aislamiento bacteriano, tinción diferencial y utilización de las pruebas bioquímicas como: TSI, SIM, Citrato de Simmons, Urea, Lisina, Catalasa y Oxidasa, además de la utilización de medios de cultivo selectivo y diferencial como agar EMB y agar MacConkey para la identificación de bacterias entéricas como: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. Los resultados arrojaron que la frecuencia bacteriana de las superficies inertes de los restaurantes en el área de preparación de alimentos (mesón y tabla de picar) tienen presencia de bacterias: Salmonella con mayor frecuencia; E. coli, Klebsiella pneumoniae y Pseudomonas aeruginosa de mediana frecuencia y de baja para Shigella, y en el área de consumo de alimentos (mesas) la bacteria de mayor frecuencia es la E. coli y Shigella, la Klebsiella pneumoniae de mediana y Pseudomona aeruginosa se encuentra en baja frecuencia. Se llegó a la conclusión que las superficies inertes tanto en el área de preparación como en el área de consumo de alimentos se encuentran contaminados por lo que hay un riesgo de infección alimentaria para los comensales de la Universidad Técnica de Machala.

Contamination of preparation areas when coming into contact with raw or cooked foods, which is why one of the main causes of contamination of inert surfaces is inadequate handling of food when it is being prepared. With the aim of controlling the application of hygiene standards in the areas of food preparation and consumption through microbiological analysis to reduce the risks of food contamination. This research is descriptive in nature, in which a visual inspection of the establishment was carried out with the purpose of evaluating the sanitary and hygienic conditions, through the application of the Technical Guide for the Microbiological Analysis of Surfaces in Contact with Food and Beverages. For the microbiological analysis of the samples, inoculation techniques, streaking method, bacterial isolation, differential staining and use of biochemical tests such as: TSI, SIM, Simmons Citrate, Urea, Lysine, Catalase and Oxidase, in addition to use of selective and differential culture media such as EMB agar and MacConkey agar for the identification of enteric bacteria such as: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. The results showed that the bacterial frequency of the inert surfaces of the restaurants in the food preparation area (counter and cutting board) have the presence of bacteria: Salmonella more frequently; E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa of medium frequency and low frequency for Shigella, and in the food consumption area (tables) the most frequent bacteria are E. coli and Shigella, Klebsiella pneumoniae of medium and Pseudomona aeruginosa It is at low frequency. It was concluded that the inert surfaces in both the preparation area and the food consumption area are contaminated, so there is a risk of food infection for diners at the Technical University of Machala

Contaminação das áreas de preparo ao entrar em contato com alimentos crus ou cozidos, por isso uma das principais causas de contaminação de superfícies inertes é o manuseio inadequado dos alimentos no momento do preparo. Com o objetivo de controlar a aplicação de padrões de higiene nas áreas de preparação e consumo de alimentos através de análises microbiológicas para reduzir os riscos de contaminação alimentar. Esta pesquisa é de natureza descritiva, na qual foi realizada uma inspeção visual do estabelecimento com a finalidade de avaliar as condições sanitárias e higiênicas, por meio da aplicação do Guia Técnico para Análise Microbiológica de Superfícies em Contato com Alimentos e Bebidas. Para a análise microbiológica das amostras foram utilizadas técnicas de inoculação, método de estrias, isolamento bacteriano, coloração diferencial e utilização de testes bioquímicos como: TSI, SIM, Citrato de Simmons, Ureia, Lisina, Catalase e Oxidase, além de utilização de testes seletivos e diferenciais. meios de cultura como ágar EMB e ágar MacConkey para identificação de bactérias entéricas como: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. Os resultados mostraram que a frequência bacteriana das superfícies inertes dos restaurantes na área de preparo de alimentos (balcão e tábua de corte) apresentam com maior frequência a presença de bactérias: Salmonella; E. coli, Klebsiella pneumoniae e Pseudomonas aeruginosa de média frequência e baixa frequência para Shigella, e na área de consumo alimentar (tabelas) as bactérias mais frequentes são E. coli e Shigella, Klebsiella pneumoniae de média e Pseudomona aeruginosa Está em baixa frequência. Concluiu-se que as superfícies inertes tanto na área de preparação como na área de consumo de alimentos estão contaminadas, pelo que existe risco de infecção alimentar para os comensais da Universidade Técnica de Machala

Assuntos

RESUMO

La contaminación de las áreas de preparación al entrar en contacto con los alimentos crudos o cocinados, es por esto que una de las principales causas de la contaminación de las superficies inertes es la inadecuada manipulación de los alimentos a la hora de ser preparados. Con el objetivo de controlar la aplicación de normas de higiene en las áreas de preparación y consumo de alimentos mediante análisis microbiológicos para disminuir los riesgos de contaminación alimentaria. Esta investigación es de carácter descriptivo, en la cual se realizó una inspección visual del establecimiento con el propósito de evaluar las condiciones higiénicas sanitarias, mediante la aplicación de la Guía Técnica para el Análisis Microbiológico de Superficies en contacto con Alimentos y Bebidas. Para el análisis microbiológico de las muestras se emplearon las técnicas de inoculación, método de estriado, aislamiento bacteriano, tinción diferencial y utilización de las pruebas bioquímicas como: TSI, SIM, Citrato de Simmons, Urea, Lisina, Catalasa y Oxidasa, además de la utilización de medios de cultivo selectivo y diferencial como agar EMB y agar MacConkey para la identificación de bacterias entéricas como: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. Los resultados arrojaron que la frecuencia bacteriana de las superficies inertes de los restaurantes en el área de preparación de alimentos (mesón y tabla de picar) tienen presencia de bacterias: Salmonella con mayor frecuencia; E. coli, Klebsiella pneumoniae y Pseudomonas aeruginosa de mediana frecuencia y de baja para Shigella, y en el área de consumo de alimentos (mesas) la bacteria de mayor frecuencia es la E. coli y Shigella, la Klebsiella pneumoniae de mediana y Pseudomona aeruginosa se encuentra en baja frecuencia. Se llegó a la conclusión que las superficies inertes tanto en el área de preparación como en el área de consumo de alimentos se encuentran contaminados por lo que hay un riesgo de infección alimentaria para los comensales de la Universidad Técnica de Machala.

Contamination of preparation areas when coming into contact with raw or cooked foods, which is why one of the main causes of contamination of inert surfaces is inadequate handling of food when it is being prepared. With the aim of controlling the application of hygiene standards in the areas of food preparation and consumption through microbiological analysis to reduce the risks of food contamination. This research is descriptive in nature, in which a visual inspection of the establishment was carried out with the purpose of evaluating the sanitary and hygienic conditions, through the application of the Technical Guide for the Microbiological Analysis of Surfaces in Contact with Food and Beverages. For the microbiological analysis of the samples, inoculation techniques, streaking method, bacterial isolation, differential staining and use of biochemical tests such as: TSI, SIM, Simmons Citrate, Urea, Lysine, Catalase and Oxidase, in addition to use of selective and differential culture media such as EMB agar and MacConkey agar for the identification of enteric bacteria such as: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. The results showed that the bacterial frequency of the inert surfaces of the restaurants in the food preparation area (counter and cutting board) have the presence of bacteria: Salmonella more frequently; E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa of medium frequency and low frequency for Shigella, and in the food consumption area (tables) the most frequent bacteria are E. coli and Shigella, Klebsiella pneumoniae of medium and Pseudomona aeruginosa It is at low frequency. It was concluded that the inert surfaces in both the preparation area and the food consumption area are contaminated, so there is a risk of food infection for diners at the Technical University of Machala.

Contaminação das áreas de preparo ao entrar em contato com alimentos crus ou cozidos, por isso uma das principais causas de contaminação de superfícies inertes é o manuseio inadequado dos alimentos no momento do preparo. Com o objetivo de controlar a aplicação de padrões de higiene nas áreas de preparação e consumo de alimentos através de análises microbiológicas para reduzir os riscos de contaminação alimentar. Esta pesquisa é de natureza descritiva, na qual foi realizada uma inspeção visual do estabelecimento com a finalidade de avaliar as condições sanitárias e higiênicas, por meio da aplicação do Guia Técnico para Análise Microbiológica de Superfícies em Contato com Alimentos e Bebidas. Para a análise microbiológica das amostras foram utilizadas técnicas de inoculação, método de estrias, isolamento bacteriano, coloração diferencial e utilização de testes bioquímicos como: TSI, SIM, Citrato de Simmons, Ureia, Lisina, Catalase e Oxidase, além de utilização de testes seletivos e diferenciais. meios de cultura como ágar EMB e ágar MacConkey para identificação de bactérias entéricas como: E. coli, Salmonella, Klebsiella pneumoniae, Shigella, Pseudomona aeruginosa. Os resultados mostraram que a frequência bacteriana das superfícies inertes dos restaurantes na área de preparo de alimentos (balcão e tábua de corte) apresentam com maior frequência a presença de bactérias: Salmonella; E. coli, Klebsiella pneumoniae e Pseudomonas aeruginosa de média frequência e baixa frequência para Shigella, e na área de consumo alimentar (tabelas) as bactérias mais frequentes são E. coli e Shigella, Klebsiella pneumoniae de média e Pseudomona aeruginosa Está em baixa frequência . Concluiu-se que as superfícies inertes tanto na área de preparação como na área de consumo de alimentos estão contaminadas, pelo que existe risco de infecção alimentar para os comensais da Universidade Técnica de Machala.

RESUMO

The global market of sweet potato (Ipomoea batatas (L.) Lam.) is continuously growing and, consequently, demands greater productivity from the agricultural sector. The use of biofertilizers facilitates plant growth by making essential nutrients available to crops or providing resistance against different abiotic and biotic factors. The strains Bacillus safensis T052-76 and Bacillus velezensis T149-19 have previously been inoculated in the sweet potato cultivar Ourinho, showing positive effects on plant shoot growth and inhibiting the phytopathogen Plenodomus destruens. To elucidate the effects of these strains on sweet potato growth, four different cultivars of sweet potato were selected: Capivara, IAPAR 69, Rosinha de Verdan and Roxa. The plants were grown in pots in a greenhouse and inoculated with the combined strains according to a randomized block design. A control (without the inoculation of both strains) was also used. A slight positive effect of the inoculation of the two Bacillus strains was observed on the aerial parts of some of the cultivars. An increase in the fresh weight of the sweet potatoes of the inoculated plants was obtained, varying from 2.7 to 11.4 %. The number of sweet potatoes obtained from the inoculated cultivars IAPAR 69 and Roxa increased 15.2 % and 16.7 %, respectively. The rhizosphere soil of each cultivar was further sampled for DNA extraction, and the 16S rRNA gene metabarcoding technique was used to determine how the introduction of these Bacillus strains influenced the rhizosphere bacterial community. The bacterial communities of the four different cultivars were dominated by Actinobacteria, Proteobacteria and Firmicutes. Nonmetric multidimensional scaling (NMDS) revealed that the rhizosphere bacterial communities of plants inoculated with Bacillus strains were more similar to each other than to the bacterial communities of uninoculated plants. This study highlights the contribution of these Bacillus strains to the promotion of sweet potato growth.

RESUMO

Antimicrobial resistance presents a substantial threat to global public health, demanding urgent attention and action. This study focuses on lanthipeptides, ribosomally encoded peptides that display significant structural diversity and hold promising potential as antibiotics. Genome mining was employed to locate biosynthetic gene clusters (BGCs) containing class II lanthipeptide synthetases encoded by lanM genes. A phylogenetic study analyzing homologous sequences of functional LanM sequences revealed a unique evolutionary clade of 17 LanM proteins associated with 12 Clostridium bacterial genomes. In silico exploration identified nine complete BGCs, including one super-cluster containing two co-localized operons from Clostridium cellulovorans 743B, that encode for two new peptides named clostrisin and cellulosin. Each operon was heterologously expressed in Escherichia coli. Molecular weights associated with the expected post-translational modifications of the purified lanthipeptide were confirmed by MS-MS/MS analysis for cellulosin, while clostrisin was not post-translationally modified. Both peptides demonstrated antimicrobial activity against multidrug-resistant bacteria, such as a clinical strain of Staphylococcus epidermidis MIQ43 and Pseudomonas aeruginosa PA14. This is the first report of lanthipeptides from the Clostridium genus produced with its native biosynthetic machinery, as well as chemically and biologically characterized. This study showcases the immense potential of genome mining in identifying new RiPP synthetases and associated bioactive peptides.

RESUMO

BACKGROUND: Resistant infectious diseases caused by gram-negative bacteria are among the most serious worldwide health problems. Antimicrobial peptides (AMPs) have been explored as promising antibacterial, antibiofilm, and anti-infective candidates to address these health challenges. MAJOR CONCLUSIONS: Here we report the potent antibacterial effect of the peptide PaDBS1R6 on clinical bacterial isolates and identify an immunomodulatory peptide fragment incorporated within it. PaDBS1R6 was evaluated against Acinetobacter baumannii and Escherichia coli clinical isolates and had minimal inhibitory concentration (MIC) values from 8 to 32 µmol L-1. It had a rapid bactericidal effect, with eradication showing within 3 min of incubation, depending on the bacterial strain tested. In addition, PaDBS1R6 inhibited biofilm formation for A. baumannii and E. coli and was non-toxic toward healthy mammalian cells. These findings are explained by the preference of PaDBS1R6 for anionic membranes over neutral membranes, as assessed by surface plasmon resonance assays and molecular dynamics simulations. Considering its potent antibacterial activity, PaDBS1R6 was used as a template for sliding-window fr agmentation studies (window size = 10 residues). Among the sliding-window fragments, PaDBS1R6F8, PaDBS1R6F9, and PaDBS1R6F10 were ineffective against any of the bacterial strains tested. Additional biological assays were conducted, including nitric oxide (NO) modulation and wound scratch assays, and the R6F8 peptide fragment was found to be active in modulating NO levels, as well as having strong wound healing properties. GENERAL SIGNIFICANCE: This study proposes a new concept whereby peptides with different biological properties can be derived by the screening of fragments from within potent AMPs.

RESUMO

AIMS: This study aimed to describe the bacterial microbiome associated with the carapace of three species of Galapagos giant tortoises (Chelonoidis porteri, Chelonoidis donfaustoi, and Chelonoidis vandenburghi) and determine the potential effect of the whitish lesions caused by the fungus Aphanoascella galapagosensis. METHODS AND RESULTS: We used Oxford Nanopore's MinION to evaluate the external bacterial microbiome associated with the carapaces from the aforementioned species. Taxonomic assignment was carried out by Bugseq and the bacterial communities were compared between carapaces with and without lesions using a NMDS with Bray-Curtis as the dissimilarity index. We found four genera of bacteria that were ubiquitous throughout all individuals, suggesting the presence of shared taxa. The results also displayed a significant difference in the microbiome between carapaces with and without lesions, and for species-carapace interaction, but not among species. CONCLUSIONS: This study establishes a baseline of the bacterial diversity of the carapace within three Galapagos giant tortoise species, showcasing the presence of a distinctive microbial community. Furthermore, our findings suggest a significant influence of the fungus Aphanoascella galapagosensis on the bacterial populations inhabiting the carapace of these reptiles.

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BACKGROUND: Analyze the incidence, risk factors, and fatality rates of bloodstream infections by Gram-negative bacteria (GNB-BSIs) in a Neonatal Intensive Care Unit. METHODS: This study employs a retrospective cohort design utilizing records of neonates admitted to the Neonatal Intensive Care Unit between January 2015 and June 2022. RESULTS: Among 1,495 neonates, 5.2% developed GNB-BSIs. The average incidence of infection per 1,000 patient-days was 2.9. Primary risk factors for infection that included preceeding carbapenem use were significant risk factors (odds ratio=514.4; P < .01) and fourth-generation cephalosporins (odds ratio=66; P < .01). Among the 85 GNB, 75.3% were fermenters, and 24.7% were non-fermenters. Of the isolates, 14.1% produced extended-spectrum beta-lactamase, and 2.3% carbapenem-resistant. Infection correlated with prolonged hospital stays (10-39days) and increased mortality (10%-29.9%). CONCLUSIONS: The high incidence of GNB-BSIs was exacerbated by the preceeding use of broad-spectrum antimicrobials, increasing the presence of multidrug-resistant isolates and fatality rates. These findings emphasize the importance of active surveillance.

RESUMO

This study presents comprehensive insights into the microbiological profile across all concentrated chicken broth processing stages, utilizing a combination of amplicon sequencing based on metataxonomic and culturing techniques. Samples were systematically collected throughout the production chain, with each batch yielding 10 samples per day across eight different dates. These samples underwent thorough analysis, including 16S rRNA and ITS sequencing (n = 30), culture-dependent microbiological tests (n = 40), and physical-chemical characterization (n = 10). Culturing analysis revealed the absence of Listeria monocytogenes and Salmonella spp. at any stage of processing, counts of various microorganisms such as molds, yeasts, Enterobacteria, and others remained below detection limits. Notably, spore counts of selected bacterial groups were observed post-processing, indicating the persistence of certain species, including Bacillus cereus and Clostridium perfringens, albeit in low counts. Furthermore, the study identified a diverse array of bacterial and fungal species throughout the processing chain, with notable occurrence of spore-forming bacteria. The presence of spore-forming bacteria in the final product, despite thermal processing, suggests the need for enhanced strategies to mitigate their introduction and persistence in the processing premises. Thus, this study offers valuable insights into microbial dynamics and diversity through processing concentrated chicken broth.

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RESUMO

The organic acids produced by lactic acid bacteria (LAB) during the fermentation of sourdoughs have the ability to reduce the growth of different molds. However, this ability depends on the LAB used. For this reason, in this study, the proportions of different LAB were optimized to obtain aqueous extracts (AEs) from sourdough to reduce fungal growth in vitro, control the acetic acid concentration, and obtain a specific lactic to acetic acid ratio. In addition, the optimized mixtures were used to formulate partially baked bread (PBB) and evaluate the mold growth and bread quality during refrigerated storage. Using a simplex-lattice mixture design, various combinations of Lactiplantibacillus plantarum, Lacticaseibacillus casei, and Lactobacillus acidophilus were evaluated for their ability to produce organic acids and inhibit mold growth. The mixture containing only Lpb. plantarum significantly reduced the growth rates and extended the lag time of Penicillium chrysogenum and P. corylophilum compared with the control. The AEs' pH values ranged from 3.50 to 3.04. Organic acid analysis revealed that using Lpb. plantarum yielded higher acetic acid concentrations than when using mixed LAB. This suggests that LAB-specific interactions significantly influence organic acid production during fermentation. The reduced radial growth rates and extended lag times for both molds compared to the control confirmed the antifungal properties of the AEs from the sourdoughs. Statistical analyses of the mixture design using polynomial models demonstrated a good fit for the analyzed responses. Two optimized LAB mixtures were identified that maximized mold lag time, targeted the desired acetic acid concentration, and balanced the lactic to acetic acid ratio. The addition of sourdough with optimized LAB mixtures to PBB resulted in a longer shelf life (21 days) and adequately maintained product quality characteristics during storage. PBB was subjected to complete baking and sensory evaluation. The overall acceptability was slightly higher in the control without sourdough (7.50), followed by bread formulated with the optimized sourdoughs (ranging from 6.78 to 7.10), but the difference was not statistically significant (p > 0.05). The sensory analysis results indicated that the optimization was used to successfully formulate a sourdough bread with a sensory profile closely resembling that of a nonsupplemented one. The designed LAB mixtures can effectively enhance sourdough bread's antifungal properties and quality, providing a promising approach for extending bread shelf life while maintaining desirable sensory attributes.