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1.
Food Microbiol ; 123: 104596, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038898

RESUMEN

This study evaluated the use of acerola (Malpighia glabra L., CACE), cashew (Anacardium occidentale L., CCAS), and guava (Psidium guayaba L., CGUA) fruit processing coproducts as substrates to promote the growth, metabolite production, and maintenance of the viability/metabolic activity of the probiotics Lactobacillus acidophilus LA-05 and Lacticaseibacillus paracasei L-10 during cultivation, freeze-drying, storage, and exposure to simulated gastrointestinal digestion. Probiotic lactobacilli presented high viable counts (≥8.8 log colony-forming units (CFU)/mL) and a short lag phase during 24 h of cultivation in CACE, CCAS, and CGUA. Cultivation of probiotic lactobacilli in fruit coproducts promoted sugar consumption, medium acidification, and production of organic acids over time, besides increasing the of several phenolic compounds and antioxidant activity. Probiotic lactobacilli cultivated in fruit coproducts had increased survival percentages after freeze-drying and during 120 days of refrigerated storage. Moreover, probiotic lactobacilli cultivated and freeze-dried in fruit coproducts had larger subpopulations of live and metabolically active cells when exposed to simulated gastrointestinal digestion. The results showed that fruit coproducts not only improved the growth and helped to maintain the viability and metabolic activity of probiotic strains but also enriched the final fermented products with bioactive compounds, being an innovative circular strategy for producing high-quality probiotic cultures.


Asunto(s)
Frutas , Probióticos , Probióticos/metabolismo , Frutas/microbiología , Lactobacillus acidophilus/crecimiento & desarrollo , Lactobacillus acidophilus/metabolismo , Lactobacillus acidophilus/fisiología , Anacardium/microbiología , Anacardium/crecimiento & desarrollo , Psidium/crecimiento & desarrollo , Psidium/microbiología , Malpighiaceae/crecimiento & desarrollo , Malpighiaceae/microbiología , Liofilización , Viabilidad Microbiana , Lacticaseibacillus paracasei/crecimiento & desarrollo , Lacticaseibacillus paracasei/metabolismo , Lacticaseibacillus paracasei/fisiología , Fermentación , Manipulación de Alimentos/métodos
2.
Acta Paul. Enferm. (Online) ; 37: eAPE002191, 2024. tab, graf
Artículo en Portugués | LILACS, BDENF - Enfermería | ID: biblio-1527574

RESUMEN

Resumo Objetivo Avaliar a eficácia antimicrobiana de um dispositivo fixo emissor de luz UV-C na desinfecção de diferentes superfícies do ambiente hospitalar e sua eficácia antifúngica na qualidade do ar. Métodos Estudo quase-experimental realizado em uma unidade de internação hospitalar, que utilizou o Bioamostrador de ar Andersen® de seis estágios para análise do ar; e na avaliação das superfícies, utilizaram-se três suspensões de microrganismos (Acinetobacter sp. MDR, Escherichia coli e Klebsiella pneumoniae produtora de KPC) para contaminar o ambiente. Para ambos foram feitas coletas pré (controle) e pós-acionamento da luz UV-C (teste). Resultados Na avaliação do ar houve uma redução importante da contagem de colônias após a luz UV-C e não foram encontrados fungos patogênicos ou toxigênicos em nenhum dos dois momentos. Em relação à desinfecção das superfícies, nenhum crescimento bacteriano foi observado após a intervenção da luz, demonstrando 100% de inativação bacteriana nas condições testadas. Conclusão A utilização da tecnologia com emissão de luz UV-C fixa foi eficaz e pode ser considerada uma intervenção promissora para protocolos de desinfecção de superfícies hospitalares.


Resumen Objetivo Evaluar la eficacia antimicrobiana de un dispositivo fijo emisor de luz UV-C para la desinfección de diferentes superficies del ambiente hospitalario y su eficacia antifúngica en la calidad del aire. Métodos Estudio cuasi experimental realizado en una unidad de internación hospitalaria, en que se utilizó el biomuestreador de aire Andersen® de seis etapas para el análisis del aire. En el análisis de las superficies, se utilizaron tres suspensiones de microorganismos (Acinetobacter sp. MDR, Escherichia coli y Klebsiella pneumoniae productora de KPC) para contaminar el ambiente. En ambos se tomó una muestra antes (control) y después de accionar la luz UV-C (prueba). Resultados En el análisis del aire hubo una reducción importante del recuento de colonias después de la luz UV-C y no se encontraron hongos patógenos ni toxigénicos en ninguno de los dos momentos. Con relación a la desinfección de las superficies, no se observó ningún crecimiento bacteriano después de la intervención de la luz, lo que demuestra un 100 % de inactivación bacteriana en las condiciones analizadas. Conclusión El uso de la tecnología con emisión de luz UV-C fija fue eficaz y puede ser considerada una intervención prometedora para protocolos de desinfección de superficies hospitalarias.


Abstract Objective To evaluate a fixed UV-C light emitting device for its antimicrobial effectiveness in the disinfection of distinct surfaces and its antifungal effectiveness on air quality in the hospital environment. Methods This quasi-experimental study was conducted in a hospital inpatient unit, in which a six-stage air Biosampler (Andersen®) was used for air analysis. In the evaluation of surfaces, three suspensions of microorganisms (Acinetobacter sp. multidrug-resistant, Escherichia coli, and KPC-producing Klebsiella pneumoniae) were used to contaminate the environment. In both evaluations, pre- (control) and post-activation of UV-C light (test) collections were made. Results In the air evaluation, an important reduction was observed in the colony count after irradiation with UV-C light, and pathogenic or toxigenic fungi were not found in either of the two moments. Regarding the disinfection of surfaces, no bacterial growth was observed after the application of UV-C light, showing 100% bacterial inactivation under the tested conditions. Conclusion The use of fixed UV-C light emission technology was effective and can be considered a promising intervention for hospital surface disinfection protocols.


Asunto(s)
Rayos Ultravioleta , Desinfección/métodos , Control de Infecciones , Aire/parasitología , Microbiología del Aire , Hospitalización , Estudios de Evaluación como Asunto , Ensayos Clínicos Controlados no Aleatorios como Asunto
3.
Braz J Microbiol ; 54(1): 323-334, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36740644

RESUMEN

The growth of the lactic acid bacteria (LAB), Streptococcus thermophilus and Lactobacillus bulgaricus, widely used for yogurt production, results in acid production and the reduction of the milk [Formula: see text]. Industrial processes can show temperature ([Formula: see text]) changes due to the large scale of the equipment. As [Formula: see text] and [Formula: see text] affect the LAB growth, this study aimed to model the dependence of S. thermophilus and L. bulgaricus as a function of temperature and pH and to estimate and internally validate their growth parameters and confidence intervals with different modeling approaches. Twenty-four datasets regarding the growth kinetics of S. thermophilus and L. bulgaricus were used for estimating the kinetic parameters for each pure culture. The classical Baranyi and Roberts (sigmoidal) primary and Rosso and coworkers (cardinal parameter) secondary models successfully described the experimental data. The one-step modeling approach showed better statistical results than the two-step approach. The values of eight growth parameters ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text]) for each culture estimated from the fitting with the one-step approach and the Monte-Carlo-based approach were similar. Low averaged root-mean-squared errors ([Formula: see text]) (0.125 and 0.090 log CFU/mL) and percent discrepancy factor [Formula: see text] ([Formula: see text] and [Formula: see text]) values for S. thermophilus and L. bulgaricus were obtained in the internal model validation, reinforcing the predictive ability of the model.


Asunto(s)
Lactobacillus delbrueckii , Streptococcus thermophilus , Lactobacillus , Temperatura , Concentración de Iones de Hidrógeno , Fermentación
4.
Braz. J. Biol. ; 83: 1-10, 2023. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-765488

RESUMEN

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.(AU)


Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.(AU)


Asunto(s)
Oligoquetos , Antibacterianos/análisis , Antibacterianos/farmacología , Ampicilina , Azitromicina
5.
Braz. j. biol ; 83: e247016, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1339416

RESUMEN

Abstract Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Resumo Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.


Asunto(s)
Animales , Oligoquetos , Staphylococcus aureus , Pruebas de Sensibilidad Microbiana , Ampicilina/farmacología , Antibacterianos/farmacología
6.
Braz. j. biol ; 83: 1-10, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468911

RESUMEN

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.


Asunto(s)
Ampicilina , Antibacterianos/análisis , Antibacterianos/farmacología , Azitromicina , Oligoquetos
7.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469127

RESUMEN

Abstract Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Resumo Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.

8.
Odontoestomatol ; 24(40)dic. 2022.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1431010

RESUMEN

Streptococcus sanguinis forma parte del biofilm bucal, tiene función decisoria en el desarrollo de las enfermedades bucales prevalentes y a nivel sistémico actúa como patógeno oportunista. Objetivo: Evaluar in vitro los efectos del xilitol en el crecimiento bacteriano frente a Streptococcus sanguinis (ATCC 10556). Métodos: la muestra del estudio fue distribuida en 6 grupos: 4 grupos experimentales (xilitol 1M; 0,75M; 0,50M y 0,25M), un control negativo (agua destilada) y un control positivo (clorhexidina); el análisis estadístico se hizo mediante el software estadístico Infostat y se empleó las pruebas t-Student, ANOVA y Tukey para contrastar la hipótesis. Resultados: diferentes concentraciones de xilitol (0,25M; 0,50M; 0,75M y 1M) causaron un halo de inhibición entre 9,89 - 12,89 mm (24 horas) y 10,85 - 13,45 mm (48 horas). Conclusiones: diferentes concentraciones de xilitol inhiben el crecimiento bacteriano del Streptococcus sanguinis, este efecto inhibitorio aumenta a mayor concentración y tiempo de exposición.


Streptococcus sanguinis faz parte do biofilme oral, tem papel decisivo no desenvolvimento de doenças bucais prevalentes e atua como patógeno oportunista em nível sistêmico. Objetivo: Avaliar in vitro os efeitos do xilitol no crescimento bacteriano contra Streptococcus sanguinis (ATCC 10556). Métodos: A amostra do estudo foi distribuída em 6 grupos: 4 grupos experimentais (1M; 0,75M; 0,50M e 0,25M xilitol), um controle negativo (água destilada) e um controle positivo (clorexidina); a análise estatística foi feita com o software estatístico Infostat e os testes t-Student, ANOVA e Tukey para testar a hipótese. Resultados: diferentes concentrações de xilitol (0,25M; 0,50M; 075M e 1M) causou um halo de inibição entre 9,89 - 12,89 mm (24 horas) e 10,85 - 13,45 mm (48 horas). Conclusões: diferentes concentrações de xilitol inibem o crescimento bacteriano de Streptococcus sanguinis, este efeito inibitório aumenta com maior concentração e tempo de exposição.


Streptococcus sanguinis forms part of the oral biofilm, has a decisive role in the development of prevalent oral diseases and acts as an opportunistic pathogen at the systemic level. Aims: To evaluate in vitro the effects of xylitol on bacterial growth against Streptococcus sanguinis (ATCC 10556). Methods: The study sample was distributed into 6 groups: 4 experimental groups (1M; 0,75M; 0,50M and 0,25M xylitol), a negative control (distilled water) and a positive control (chlorhexidine). The statistical analysis was done using the statistical software Infostat and the tests used t-Student, ANOVA and Tukey to test the hypothesis. Results: different concentrations of xylitol (0,25M; 0,50M; 0,75M and 1M) caused an inhibition halo between 9,89 - 12,89 mm (24 hours) and 10,85 - 13,45 mm (48 hours). Conclusions: different concentrations of xylitol inhibit the bacterial growth of Streptococcus sanguinis, this inhibitory effect increases with higher concentration and exposure time.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36361104

RESUMEN

Phenol is used in the manufacturing process of phenolic resins from which residues remain that must be sent for confinement. For that reason, in this study, the wastewater of a resin factory was analyzed to isolate the bacteria present, identify them by molecular methods and finally evaluate their impact on bioremediation treatment. A total of 15 bacteria were isolated, of these, eight belong to the genus Bacillus spp. All bacteria were individually multiplied and inoculated in clusters in 15 L reactors which were carefully monitored for pH, electrical conductivity, chemical oxygen demand and temperature. The acquired data were analyzed using ANOVA with repeated measurements. The first test revealed that native bacterial communities reduce the phenol content by up to 20% and COD by 49%, which is significant with respect to the reactor not being inoculated with bacteria. Furthermore, when a mathematical model was applied to the reactors, it was shown that the bacteria require an adaptation time of approximately 100 h. A second test where the inoculation was interspersed with the addition of lime as a flocculant showed that, even though the reduction in phenol and COD was lower than in the previous test, the difference between treatments and control is statistically significant (α ≤ 0.05).


Asunto(s)
Fenol , Aguas Residuales , Fenol/química , Biodegradación Ambiental , Aguas Residuales/microbiología , Fenoles , Bacterias , Reactores Biológicos/microbiología , Eliminación de Residuos Líquidos/métodos
10.
Microorganisms ; 10(9)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36144427

RESUMEN

In this work, we evaluated the direct effect of a dialkyl carbamoyl chloride (DACC)-coated dressing on Staphylococcus aureus adhesion and growth in vitro, as well as the indirect effect of the dressing on fibroblast and macrophage activity. S. aureus cultures were treated with the dressing or gauze in Müller-Hinton medium or serum-supplemented Dulbecco's modified Eagle medium. Bacterial growth and attachment were assessed through colony-forming units (CFU) and residual biomass analyses. Fibroblast and macrophage co-cultures were stimulated with filtered supernatants from the bacterial cultures treated with the DACC-coated dressing, following which tumor necrosis factor (TNF)-α/transforming growth factor (TGF)-ß1 expression and gelatinolytic activity were assessed by enzyme-linked immunosorbent assays (ELISA) and zymography, respectively. The DACC-coated dressing bound 1.8−6.1% of all of the bacteria in the culture. Dressing-treated cultures presented biofilm formation in the dressing (enabling mechanical removal), with limited formation outside of it (p < 0.001). Filtered supernatants of bacterial cultures treated with the DACC-coated dressing did not over-stimulate TNF-α or TGF-ß1 expression (p < 0.001) or increase gelatinolytic activity in eukaryotic cells, suggesting that bacterial cell integrity was maintained. Based on the above data, wound caregivers should consider the use of hydrophobic dressings as a first option for the management of acute or chronic wounds.

11.
BMC Microbiol ; 22(1): 218, 2022 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-36114465

RESUMEN

BACKGROUND: Rhizosphere microorganisms play a crucial role in plant health and development. Plant root exudates (PRE) are a complex mixture of organic molecules and provide nutritional and signaling information to rhizosphere microorganisms. Burkholderiaceae species are non-abundant in the rhizosphere but exhibit a wide range of plant-growth-promoting and plant-health-protection effects. Most of these plant-associated microorganisms have been studied in isolation under laboratory conditions, whereas in nature, they interact in competition or cooperation with each other. To improve our understanding of the factors driving growth dynamics of low-abundant bacterial species in the rhizosphere, we hypothesized that the growth and survival of four Burkholderiaceae strains (Paraburkholderia phytofirmans PsJN, Cupriavidus metallidurans CH34, C. pinatubonensis JMP134 and C. taiwanensis LMG19424) in Arabidopsis thaliana PRE is affected by the presence of each other. RESULTS: Differential growth abilities of each strain were found depending on plant age and whether PRE was obtained after growth on N limitation conditions. The best-adapted strain to grow in PRE was P. phytofirmans PsJN, with C. pinatubonensis JMP134 growing better than the other two Cupriavidus strains. Individual strain behavior changed when they succeeded in combinations. Clustering analysis showed that the 4-member co-culture grouped with one of the best-adapted strains, either P. phytofirmans PsJN or C. pinatubonensis JMP134, depending on the PRE used. Sequential transference experiments showed that the behavior of the 4-member co-culture relies on the type of PRE provided for growth. CONCLUSIONS: The results suggest that individual strain behavior changed when they grew in combinations of two, three, or four members, and those changes are determined first by the inherent characteristics of each strain and secondly by the environment.


Asunto(s)
Arabidopsis , Burkholderia , Burkholderiaceae , Arabidopsis/microbiología , Mezclas Complejas , Exudados y Transudados , Estado Nutricional , Plantas
12.
Arq. bras. med. vet. zootec. (Online) ; 74(4): 671-676, July-Aug. 2022. tab
Artículo en Inglés | VETINDEX | ID: biblio-1393910

RESUMEN

Infection caused by Aeromonas brings great harm to fish farming. Among the factors associated with bacterial pathogenesis, iron uptake can contribute to the survival and virulence of bacteria within hosts. The aim of this study was to check the presence of genes related to iron uptake in Aeromonas hydrophila deriving from aquatic organisms in the São Francisco Valley and associate the presence of these genes with the ability to grow in media containing different concentrations of iron. The DNAs of 41 isolates were extracted and used in PCRs to verify the presence of the Fur, AmoA and pvcAB genes related to iron uptake. The growth of the isolates belonging to different genetic profiles was verified in culture media containing different iron concentrations. Two isolates were positive for the presence of the Fur gene, seven for the AmoA gene and two for the pvcAB gene. The growth test showed that the low availability of iron did not interfere in the growth of the isolates, nor in the isolate that did not contain any of the genes evaluated in this study, suggesting that the iron uptake's mechanisms of the tested isolates may be related to other genes and proteins.


Infecções causadas por Aeromonas trazem grandes prejuízos à piscicultura. Entre os fatores associados à patogênese bacteriana, a captação de ferro pode contribuir para a sobrevivência e a virulência das bactérias dentro dos hospedeiros. O objetivo deste estudo foi verificar a presença de genes relacionados à captação de ferro em Aeromonas hydrophila provenientes de organismos aquáticos do Vale do São Francisco e associar a presença desses genes com a capacidade de as bactérias crescerem em meios contendo diferentes concentrações de ferro. Os DNAs de 41 isolados foram extraídos e utilizados em PCRs para verificar a presença dos genes Fur, AmoA e pvcAB relacionados à captação de ferro. O crescimento dos isolados pertencentes a diferentes perfis genéticos foi verificado em meios de cultura contendo diferentes concentrações de ferro. Dois isolados foram positivos para a presença do gene Fur, sete para a do gene AmoA e dois para a do gene pvcAB. O teste de crescimento mostrou que a baixa disponibilidade de ferro não interferiu no crescimento dos isolados nem no isolado que não continha nenhum dos genes avaliados neste estudo, sugerindo que os mecanismos de captação de ferro dos isolados testados podem estar relacionados a outros genes e proteínas.


Asunto(s)
Animales , Crecimiento Bacteriano , Aeromonas hydrophila , Explotaciones Pesqueras , Genes , Hierro
13.
Membranes (Basel) ; 12(3)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35323802

RESUMEN

Augmenting bacterial growth is of great interest to the biotechnological industry. Hence, the effect of poly (caprolactone) fibrous scaffolds to promote the growth of different bacterial strains of biological and industrial interest was evaluated. Furthermore, different types of carbon (glucose, fructose, lactose and galactose) and nitrogen sources (yeast extract, glycine, peptone and urea) were added to the scaffold to determinate their influence in bacterial growth. Bacterial growth was observed by scanning electron microscopy; thermal characteristics were also evaluated; bacterial cell growth was measured by ultraviolet-visible spectrophotometry at 600-nm. Fibers produced have an average diameter between 313 to 766 nm, with 44% superficial porosity of the scaffolds, a glass transition around ~64 °C and a critical temperature of ~338 °C. The fibrous scaffold increased the cell growth of Escherichia coli by 23% at 72 h, while Pseudomonas aeruginosa and Staphylococcus aureus increased by 36% and 95% respectively at 48 h, when compared to the normal growth of their respective bacterial cultures. However, no significant difference in bacterial growth between the scaffolds and the casted films could be observed. Cell growth depended on a combination of several factors: type of bacteria, carbon or nitrogen sources, casted films or 3D scaffolds. Microscopy showed traces of a biofilm formation around 3 h in culture of P. aeruginosa. Water bioremediation studies showed that P. aeruginosa on poly (caprolactone)/Glucose fibers was effective in removing 87% of chromium in 8 h.

14.
Lasers Med Sci ; 37(5): 2439-2447, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35075597

RESUMEN

Photobiomodulation has been used to inactivate bacterial growth, in different laser or LED protocols. Thus, the aim of this study was to verify the inhibition of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, in ATCC strains and bacteria collected from patients with skin burns, after irradiation with LED; 300 µl of saline solution with bacterial suspension was irradiated at a concentration of 0.5-0.63, by the McFarland scale, after five serial dilutions, with evaluation of pre- and post-irradiation pH and temperature control. The cultures were placed in a bacteriological incubator at 37 °C for 24 h for later counting of colony-forming units (CFU). Data were analyzed by Shapiro-Wilk tests and single-factor ANOVA, with Tukey post hoc (p < 0.05). Both wavelengths and energy densities tested showed inhibition of bacterial growth. The comparison of the irradiated groups (ATCC) with the control group showed the following: S. aureus and P. aeruginosa 465 nm (40 J/cm2) and 630 nm (50 J/cm2) and E. coli 465 nm (40 J/cm2) and 630 nm (30 J/cm2). Among the ATCC S. aureus groups, there was a difference for 630 nm (30 J/cm2) and 465 nm (30, 40, 50 J/cm2). The bacteria from the burned patients were S. aureus (30 and 50 J/cm2) and P. aeruginosa (50 J/cm2). We conclude that different bacterial strains were reduced into colony-forming units after LED irradiation.


Asunto(s)
Terapia por Luz de Baja Intensidad , Staphylococcus aureus , Escherichia coli/efectos de la radiación , Humanos , Luz , Pseudomonas aeruginosa/efectos de la radiación , Staphylococcus aureus/efectos de la radiación
15.
Braz. j. biol ; 82: e262815, 2022. tab, graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1394105

RESUMEN

The objective of the study was to evaluate the quality of Zamzam water, holy water for Muslims and consumed for its medicinal value. The present study demonstrates the physicochemical characterization and wound healing property of Zamzam water. The physicochemical characterization of Zamzam water samples was analyzed for dissolved oxygen, pH, conductivity, total dissolved solids, redox potential, zeta potential, polydispersity index, and zeta size. The microbial quality of Zamzam water was also assessed by exposing water samples to open air. In this work, Zamzam water was also screened for the medicinal value through wound healing properties in Wistar rats. Zamzam water exhibited a unique physicochemical characterization with high levels of dissolved oxygen, zeta potential, polydispersity index, redox potential, total dissolved solids, and conductivity before exposure to open air. After open air exposure, Zamzam water resisted the growth of bacteria. The wound healing properties of Zamzam water in vivo showed a 96% of healing effect on 12th day observation. The wound healing was achieved by modulating pro-inflammatory cytokine such as interleukin -1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor -α (TNF-α). Followed by the level of apoptosis markers caspase-9 and caspase-3 were reduced. The present study proved that Zamzam water is a good-quality water and showed excellent wound healing property. Therefore, Zamzam water can be used for pharmaceutical formulations.


O objetivo do estudo foi avaliar a qualidade da água de Zamzam, água benta para os muçulmanos e consumida pelo seu valor medicinal. O presente estudo demonstra a caracterização físico-química e a propriedade cicatrizante da água de Zamzam. A caracterização físico-química das amostras de água de Zamzam foi analisada para oxigênio dissolvido, pH, condutividade, sólidos totais dissolvidos, potencial redox, potencial zeta, índice de polidispersidade e tamanho zeta. A qualidade microbiana da água de Zamzam também foi avaliada expondo amostras de água ao ar livre. Neste trabalho, a água de Zamzam também foi avaliada quanto ao valor medicinal através de propriedades cicatrizantes em ratos Wistar. A água de Zamzam exibiu uma caracterização físico-química única com altos níveis de oxigênio dissolvido, potencial zeta, índice de polidispersidade, potencial redox, sólidos totais dissolvidos e condutividade antes da exposição ao ar livre. Após a exposição ao ar livre, a água de Zamzam resistiu ao crescimento de bactérias. As propriedades de cicatrização de feridas da água de Zamzam in vivo mostraram um efeito de cicatrização de 96% no 12º dia de observação. A cicatrização da ferida foi alcançada pela modulação de citocinas pró-inflamatórias como a interleucina-1ß (IL-1ß), interleucina-6 (IL-6) e fator de necrose tumoral -α (TNF-α). Seguido pelo nível de marcadores de apoptose caspase-9 e caspase-3, estes foram reduzidos. O presente estudo provou que a água de Zamzam é ​​uma água de melhor qualidade e mostrou excelente propriedade de cicatrização de feridas. Portanto, a água de Zamzam pode ser usada para formulações farmacêuticas.


Asunto(s)
Cicatrización de Heridas , Heridas y Lesiones , Preparaciones Farmacéuticas , Agua/química
16.
Vive (El Alto) ; 5(14): 552-564, 2022.
Artículo en Español | LILACS | ID: biblio-1410356

RESUMEN

El tratamiento con ortodoncia fija produce en los pacientes una mayor acumulación de biofilm dental, siendo necesario una adecuada higiene bucal complementada con colutorios bucales. OBJETIVO: el propósito de este estudio fue evaluar la acción antibacteriana de colutorios de uso ortodóntico sobre el Streptococcus Mutans en pacientes con aparatología ortodóncica fija. MATERIALES Y MÉTODO: se realizó un estudio de diseño cuasiexperimental, comparativo, de corte longitudinal, de abordaje cuantitativo ciego simple, con un tamaño de muestra de 20 pacientes distribuidos en dos grupos de estudio para el recuento de UFC, además un control positivo y otro negativo para determinar el halo inhibitorio. RESULTADOS: los colutorios bucales Vitis® Orthodontic y Ortolacer tuvieron una disminución en el recuento de las UFC de Streptococcus Mutans hasta un 48,3% (p=0,00) y 53,2% (p=0,00) respectivamente; asimismo, hay una mayor acción antibacteriana sobre el Streptococcus Mutans del colutorio Vitis® Orthodontic que el colutorio Ortolacer (p-valor=0,009); así mismo, con un p valor = 0,000 < 0,05 a las 24 y 48 horas existe una diferencia estadística significativa en anaerobiosis que indica que el colutorio Vitis® Orthodontic genera un mayor halo inhibitorio sobre el Streptococcus Mutans. CONCLUSIONES: los colutorios bucales Vitis® Orthodontic y Ortolacer disminuyen el recuento de las UFC de Streptococcus Mutans en pacientes. Además, ambos colutorios en anaerobiosis tienen acción inhibitoria sobre el Streptococcus Mutans. Sin embargo, hay una mayor acción antibacteriana del colutorio Vitis® Orthodontic sobre el Streptococcus Mutans.


Fixed orthodontic treatment produces a greater accumulation of dental biofilm in patients, and adequate oral hygiene complemented with mouthwashes is necessary. OBJECTIVE: the purpose of this study was to evaluate the antibacterial action of mouthwashes for orthodontic use on Streptococcus Mutans in patients with fixed orthodontic appliances. MATERIALS AND METHODS: A quasi-experimental, comparative, longitudinal, single-blind, quantitative approach study was carried out with a sample size of 20 patients distributed in two study groups for the CFU count, as well as a positive and a negative control to determine the inhibitory halo. RESULTS: vitis Orthodontic and Ortolacer mouthwashes had a decrease in the CFU count of Streptococcus Mutans up to 48.3% (p=0.00) and 53.2% (p=0.00) respectively; likewise, there is a greater antibacterial action on Streptococcus Mutans of Vitis® Orthodontic mouthwash than Ortolacer mouthwash (p-value=0.009); Likewise, with a p-value = 0.000 < 0.05 at 24 and 48 hours there is a significant statistical difference in anaerobiosis indicating that Vitis® Orthodontic mouthwash generates a greater inhibitory halo on Streptococcus Mutans. CONCLUSIONS: Vitis® Orthodontic and Ortholacer mouthrinses decrease the CFU count of Streptococcus Mutans in patients. In addition, both mouthwashes in anaerobiosis have inhibitory action on Streptococcus Mutans. However, there is a greater antibacterial action of Vitis® Orthodontic mouthwash on Streptococcus Mutans.


O tratamento ortodôntico fixo leva a um aumento do acúmulo de biofilme dentário nos pacientes, e é necessária uma higiene bucal adequada complementada com lavagens bucais. OBJETIVO: o objetivo deste estudo foi avaliar a ação antibacteriana de lava bucais para uso ortodôntico em Streptococcus Mutans em pacientes com aparelhos ortodônticos fixos. MATERIAIS E MÉTODOS: um estudo quase-experimental, comparativo, longitudinal, monobloco e quantitativo foi realizado com uma amostra de 20 pacientes distribuídos em dois grupos de estudo para a contagem da UFC, assim como um controle positivo e um negativo para determinar a auréola inibitória. RESULTADOS: os enxaguatórios bucais Vitis® Orthodontic e Ortolacer tiveram uma redução na contagem de Streptococcus Mutans na UFC de até 48,3% (p=0,00) e 53,2% (p=0,00) respectivamente; também, há uma maior ação antibacteriana no Streptococcus Mutans de Vitis® Orthodontic de que os enxaguatórios bucais Ortolacer (p=0,009); Da mesma forma, com um valor p = 0,000 < 0,05 às 24 e 48 horas há uma diferença estatística significativa na anaerobiose indicando que Vitis® Orthodontic mouthwash gera uma maior auréola inibitória no Streptococcus Mutans. CONCLUSÕES: Vitis® Orthodontic e Ortolacer mouthrinses diminuem a contagem de CFU de Streptococcus Mutans em pacientes. Além disso, ambos os bochechos em anaerobiose têm ação inibitória sobre Streptococcus Mutans. Entretanto, há uma maior ação antibacteriana do Vitis® Orthodontic mouthwash em Streptococcus Mutans.


Asunto(s)
Antisépticos Bucales
17.
Microbiol Spectr ; 9(3): e0017021, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34817207

RESUMEN

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae. IMPORTANCE Invasive disease due to group B streptococcal (GBS) infection results in a wide spectrum of clinical disease in neonates. Maternal colonization by GBS is the primary risk factor for disease. The strategy recommended by the Centers for Disease Control to reduce neonatal GBS infection is the culture-based screening of all pregnant women at 35 to 37 weeks of gestation and intrapartum antibiotic prophylaxis (IAP). However, indiscriminate use of antibiotics favors the selection and spread of resistant bacteria. The global scenario of antibacterial resistance has been of great concern for public health, and natural products can be a source of new substances to help us grapple with this problem.


Asunto(s)
Antibacterianos/farmacología , Ajo/química , Extractos Vegetales/farmacología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/efectos de los fármacos , Antibacterianos/química , Cromatografía Líquida de Alta Presión , Evaluación Preclínica de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Infecciones Estreptocócicas/tratamiento farmacológico , Streptococcus agalactiae/genética , Streptococcus agalactiae/fisiología
18.
Front Microbiol ; 12: 683923, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34177870

RESUMEN

Huanglongbing is a highly destructive citrus disease associated with "Candidatus Liberibacter asiaticus" (Las), a phloem-limited and non-culturable bacterium, naturally transmitted by the psyllid Diaphorina citri. Although diverse approaches have been used to understand the molecular mechanisms involved in the pathogen-host interaction, such approaches have focused on already infected and/or symptomatic plants, missing early events in the initial days post-inoculation. This study aimed to identify the time course of Las multiplication and whole-plant colonization immediately following inoculation by infected psyllids feeding for 2 days. Thus, the experimental approach was to track Las titers after psyllid inoculation in new shoots (NS) of Citrus × sinensis (susceptible), Murraya paniculata (partially resistant), and Bergera koenigii (fully resistant). Soon after psyllid removal, Las titers dropped until the 10-12th days in all three species. Following this, Las titers increased exponentially only in C. × sinensis and M. paniculata, indicating active bacterial multiplication. In C. × sinensis, Las reached a stationary phase at ∼5 log Las cells/g of tissue from the 40th day onward, while in M. paniculata, Las increased at a lower rate of up to ∼3 log Las cells/g of tissue between the 40th and 60th days, decreasing gradually thereafter and becoming undetectable from the 160th day onward. In B. koenigii, Las titers decreased from the start and remained undetectable. In C. × sinensis, an average of 2.6 log of Las cells/g of tissue was necessary for Las to move out of 50% of the NS in 23.6 days and to colonize the rest of the plant, causing a successful infection. Conversely, the probability of Las moving out of the NS remained below 50% in M. paniculata and zero in B. koenigii. To our knowledge, this is the first study on Las dynamics and whole-plant colonization during the earliest stages of infection. Identification of critical time-points for either successful multiplication or Las resistance may help to elucidate initial events of Las-host interactions that may be missed due to longer sampling intervals and at later stages of infection.

19.
Medisan ; 25(3)2021. tab, ilus
Artículo en Español | LILACS, CUMED | ID: biblio-1287303

RESUMEN

Introducción: La sangre ovina constituye un suplemento esencial en la elaboración de medios de cultivo, dado que aporta factores nutricionales indispensables para el crecimiento y la recuperación de diversos microorganismos. Objetivo: Evaluar comparativamente el efecto de la sangre ovina, tanto citratada como desfibrinada, en medios de cultivo de base agar en cuanto al crecimiento bacteriano y la producción de hemólisis de cepas de referencia de diferentes bacterias patógenas, así como la recuperación o el aislamiento de microorganismos de muestras clínicas. Métodos: Se realizó un estudio observacional, descriptivo y transversal en 6 laboratorios de microbiología de la ciudad de Santiago de Cuba durante el año 2017, en los cuales se empleó sangre de ovinos de la raza pelibuey, para la elaboración de medios de cultivo. A cada laboratorio se le suministró tanto sangre citratada como desfibrinada y se le entregó una encuesta para valorar los resultados. Resultados: Existió un mejor crecimiento y aislamiento bacteriano en el medio suplementado con sangre desfibrinada, a pesar de que el rendimiento o los resultados en el caso de la sangre citratada resultaron satisfactorios. Conclusiones: Se confirmó la pertinencia del uso de la sangre desfibrinada como suplemento de enriquecimiento nutritivo en medios de cultivo; no obstante, quedó demostrada la utilidad de la sangre citratada en la labor de rutina del laboratorio de microbiología clínica.


Introduction: Sheep blood is an essential supplement in the elaboration of culture media, as it provides important nutritional factors for the growth and recovery of different organisms. Objective: To evaluate comparatively the effect of sheep citrated and defibrinated sheep blood in culture media with agar base as for the bacterial growth and the production of hemolysis in reference strains from different pathogen bacteria, as well as the recovery or isolation of microorganisms from clinical samples. Method: An observational, descriptive and cross-sectional was carried out in 6 microbiology laboratories in Santiago de Cuba city during 2017, in which male sheeps blood from the pelibuey breed for elaborating culture media. Each laboratory received either citrated blood or defibrinated and a survey was delivered to evaluate the results. Results: There was a better growing and bacterial isolation in the media supplemented with defibrinated blood, although yielding or results were favorable with citrated blood. Conclusions: The pertinence of the use of defibrinated blood as a supplement of nutritive enrichment in culture media was confirmed; however, the use of citrated blood was demonstrated in the routine work of the clinical microbiology laboratory.


Asunto(s)
Ovinos , Crecimiento Bacteriano , Medios de Cultivo , Hemólisis
20.
Acta sci. vet. (Online) ; 49: Pub. 1789, Feb. 26, 2021. mapas, tab
Artículo en Inglés | VETINDEX | ID: vti-761940

RESUMEN

Background: Food contamination is an important and growing public health concern due to the risk of foodborne illnesses.In this context, the egg, consumed all over the world, stands out. This food has been pointed out as a carrier of severalbacteria, causing outbreaks of food toxinfection. The production of free-range chicken (Gallus gallus domesticus) eggs hasbeen an alternative for generating income for producers in Brazil; however, there is no monitoring of the sanitary qualityof this product. The objective of this study was to identify microorganisms in 128 free-range chicken eggs sold in openmarkets in the semiarid region of Northeastern Brazil.Materials, Methods & Results: The study was carried out at commercial fairs in the state of Rio Grande do Norte, Braziliansemiarid region. The minimum number of eggs to be used was determined by the formula for simple random samples considering the following parameters: expected frequency of positive eggs of 50% (for sample maximization), 95% confidencelevel and sampling error of 10%. The minimum number of eggs to be sampled was 97; however, 128 eggs were obtained inthe period from August 2018 to April 2019. The internal content of the eggs was subjected to bacteriological culture usingan adapted methodology, and for the in vitro susceptibility assessment the disk diffusion method on Müller-Hintonagarwasused. In addition to biochemical tests, Gram-negative bacteria were subjected to microbiological diagnosis using theMALDI-TOF (Matrix Associated Laser Desorption-Ionization - Time of Flight) technique. Bacterial growth was found in40 (31.3%) eggs. The microorganisms most frequently isolated were Staphylococcus spp. (27.5%), Bacillus spp. (15%) andEnterobacter cloacae (25%). There was bacterial growth in albumens [n = 10; 7.8%] and in egg yolks [n=38; 29.7%] (P< 0.001). The antimicrobials that showed highest resistance rates were ampicillin...(AU)


Asunto(s)
Animales , Huevos/microbiología , Microbiología de Alimentos , Saneamiento de Mercados , Técnicas Bacteriológicas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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