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Rev. chil. nutr ; 47(2): 281-285, abr. 2020. tab
Article in English | LILACS | ID: biblio-1115499


Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.

Los conservantes sintéticos están ampliamente presentes en los alimentos procesados, pero la mayoría tienen potencial carcinogénico, lo que requiere el desarrollo de nuevas alternativas naturales para el control microbiano, como los extractos de frutas. El objetivo del estudio fue evaluar la caracterización química, la actividad antioxidante y antimicrobiana de la pulpa de manzana de azúcar (Annona squamosa L.). Se evaluaron las características fisicoquímicas, y se evaluó su actividad antioxidante mediante el método DPPH y antimicrobiano por difusión en disco, concentración inhibitoria mínima y concentración bactericida mínima contra cepas de Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes y Staphylococcus aureus. El análisis fisicoquímico reveló que la pulpa de manzana de azúcar tiene 75.0% de humedad, 3.0% de cenizas, 4.0% de proteínas, 0.2% de lípidos, 3.3% de fibras y 14.5% de carbohidratos. La actividad antioxidante del extracto por el método DPPH fue del 20.6%. El extracto de pulpa de la manzana de azúcar tenía zona de inhibición para Staphylococcus aureus, efecto inhibidor satisfactorio contra Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Salmonella Typhimurium, pero no presenta efecto bactericida. La pulpa de manzana de azúcar presenta niveles adecuados de nutrientes y potencial para la aplicación de alimentos debido a su actividad microbiológica y propiedades antioxidantes.

Plant Extracts/pharmacology , Annona/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effects , Carbohydrates/analysis , Plant Extracts/chemistry , Proteins/analysis , Microbial Sensitivity Tests , Escherichia coli/drug effects , Lipids/analysis , Listeria monocytogenes/drug effects , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry
Rev. Soc. Bras. Med. Trop ; 52: e20180254, 2019. graf
Article in English | LILACS | ID: biblio-985162


Abstract INTRODUCTION: Antimicrobial resistance has been reported in the drugs used for the treatment of typhoid fever. The immunomodulatory substance β-glucan can be used as an alternative therapy as it potentiates host immunity. The aims of this study are to observe the effect of Candida albicans cell wall (CCW) extract towards host immunity (TCD8+ and TCD4+ cells in spleen, intestinal sIgA) and its capacity to kill Salmonella in the intestine and liver of typhoid fever mice models. METHODS: Typhoid fever mice models were created by infecting mice with S. Typhimurium orally. Mice were divided into four groups: the Non-Infected, Infected, CCW (infected mice treated with 300 µg CCW extract/mouse once a day), and Ciprofloxacin groups (infected mice treated with 15 mg/kg BW ciprofloxacin twice a day). RESULTS: Secretory IgA (sIgA) concentrations of mice in the CCW group remained unchanged. However, their TCD4+ and TCD8+ cells increased substantially compared to those in the Non-Infected group. In the Ciprofloxacin group, sIgA concentrations increased markedly compared to those in the Non-Infected and CCW groups; TCD4+ and TCD8+ cells also increased significantly compared to those in the Infected Group, but not significant compared to those in the CCW group. Colonization of S. Typhimurium in the intestine and liver decreased significantly in the CCW and Ciprofloxacin groups compared to that in the Infected group, with the lowest reduction being found in the Ciprofloxacin group. CONCLUSIONS The inhibition of S. Typhimurium colonization by CCW is associated with the increase in TCD4+ and TCD8+ cells.

Animals , Male , Salmonella typhimurium/drug effects , Typhoid Fever/microbiology , Candida albicans/chemistry , beta-Glucans/pharmacology , Immunoglobulin A, Secretory , CD4-Positive T-Lymphocytes/microbiology , Ciprofloxacin , Microbial Sensitivity Tests , Cell Wall , CD8-Positive T-Lymphocytes/microbiology , Disease Models, Animal , Immunity, Cellular/immunology , Intestines/microbiology , Liver/microbiology , Mice , Mice, Inbred BALB C
Braz. j. infect. dis ; 22(5): 424-432, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-974235


ABSTRACT Introduction: Nontyphoidal Salmonella serotypes are the main cause of human food-borne infection, including several hospitalization cases in the developing countries. Aim: To detect the main serotypes and to characterize the antibiotic resistance of human non-enteric and enteric nontyphoidal Salmonella from clinical isolates in Brazil. Methods: Salmonella serotypes were identified by microbiological and molecular methods. Susceptibility testing to antibiotics was performed by agar disk diffusion. Real-time PCRs were carried out for the detection of the genus Salmonella as well as serotypes Typhimurium and Enteritidis. Results: A total of 307 nontyphoidal Salmonella were isolated from 289 different patients in a reference laboratory (LACEN-RS) from Southern Brazil in a six-year period (2010-2015). There were 45 isolates from emerging cases and 244 from sporadic cases in hospitalized patients. Non-enteric isolates were detected in 42.6% of the patients from sources such as urine, blood and other clinical fluids. Serological and PCR-specific tests demonstrated that Typhimurium (48.4%) and Enteritidis (18.3%) were the most frequent serotypes. Typhimurium isolates were generally resistant to three or more antibiotic classes, while Enteritidis isolates to one or two classes. Typhimurium was the most frequent serotype in all samples (48.4%), mainly among the hospitalized patients (55.6%), and presented the highest rates of multidrug resistance (59.3% of the isolates of this serotype). Further, the prevalence of this serotype increased along the years of the study in comparison to other nontyphoidal Salmonella serotypes. Conclusion: Greater public health attention should be given to prevent salmonellosis in the community and in hospital settings to reduce the rates of Typhimurium strains with multidrug resistance.

Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Young Adult , Salmonella Infections/microbiology , Salmonella Infections/epidemiology , Salmonella typhimurium/drug effects , Drug Resistance, Multiple, Bacterial , Hospitalization/statistics & numerical data , Salmonella enteritidis/isolation & purification , Salmonella enteritidis/drug effects , Salmonella typhimurium/isolation & purification , Time Factors , Brazil/epidemiology , Microbial Sensitivity Tests , Serotyping , Cross Infection/microbiology , Cross Infection/epidemiology , Prevalence , Real-Time Polymerase Chain Reaction , Serogroup , Anti-Bacterial Agents/pharmacology
Braz. j. biol ; 78(2): 345-350, May-Aug. 2018. tab
Article in English | LILACS | ID: biblio-888873


Abstract Salacia crassifolia (Mart. Ex. Schult.) G. Don. is a bush which belongs to Celastraceae family and occurs specially in Brazilian Cerrado. Its leaves, stem, seeds and fruits are popularly used for several medicinal purposes, such as antitumoral, antirheumatic, anti-inflammatory and antimicrobial. In this study, the mutagenic and antimutagenic activities of S. crassifolia stem bark fractions (hexane, ethyl acetate and hydroalcoholic) were evaluated by the Ames mutagenicity assay in Salmonella typhimurium TA98 and TA100 strains. By the obtained results, all S. crassifolia fractions did not significantly increase the number of prototrophic revertants for histidine (His+) in both S. typhimurium strains tested (p > 0.05), suggesting absence of mutagenicity. Regarding antimutagenicity, the fractions ethyl acetate and hydroalcoholic significantly decreased the number of His+ revertants colonies induced by positive control for strain TA98 (p < 0.05), demonstrating protection against mutagenicity induced by 4-nitroquinolile1-oxide, whereas the hexane fraction did not show antimutagenic effect in this strain. In the TA100 strain, all fractions of S. crassifolia protected DNA against the harmful action of sodium azide, and the hexane fraction exhibited the greatest protection in this work. Thus, it's possible conclude that the fractions of S. crassifolia tested in this study could be used in chemoprevention.

Resumo Salacia crassifolia (Mart. Ex. Schult.) G. Don. é uma árvore que pertence à família Celastraceae e ocorre especialmente no Cerrado Brasileiro. Suas folhas, caule, sementes e frutos são popularmente utilizados para vários fins medicinais, tais como antitumoral, antirreumático, anti-inflamatório e antimicrobiano. Neste estudo, nós avaliamos as atividades mutagênica e antimutagênica de frações da casca do caule de S. crassifolia (hexânica, acetato de etila e hidroalcoólica) pelo ensaio de mutagenicidade de Ames em Salmonella typhimurium, cepas TA98 e TA100. Pelos resultados obtidos todas as frações de S. crassifolia não aumentaram significativamente o número de revertentes prototróficas para histidina (His+) em ambas as cepas de S. typhimurium testadas (p > 0.05), sugerindo ausência de mutagenicidade. Em relação à antimutagenicidade, as frações acetate de etila e hidroalcoólica reduziram significativamente o número de colônias revertentes His+ induzidas pelo controle positive para a cepa TA98 (p < 0.05), demonstrando sua ação protetora contra a mutagenicidade induzida por 4-nitroquinolile1-oxide, enquanto a fração hexânica não demonstrou efeito antimutagênico nesta cepa. Na cepa TA100, todas as frações de S. crassifolia protegeram o DNA contra a ação lesiva de azida sódica, e a fração hexânica exibiu a maior proteção desse trabalho. Assim, concluímos que as frações de S. crassifolia testadas neste estudo poderiam ser utilizadas em quimioprevenção.

Antimutagenic Agents/pharmacology , Salacia/chemistry , Mutagens/toxicity , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics , Plant Extracts/toxicity , Plant Extracts/pharmacology , Mutagenicity Tests , 4-Nitroquinoline-1-oxide/toxicity
Indian J Exp Biol ; 2014 Jul; 52(7): 692-704
Article in English | IMSEAR | ID: sea-153749


The physiological role of C-reactive protein (CRP), the classical acute-phase protein, is not well documented, despite many reports on biological effects of CRP in vitro and in model systems in vivo. It has been suggested that CRP protects mice against lethal toxicity of bacterial infections by implementing immunological responses. In Achatina fulica CRP is a constitutive multifunctional protein in haemolymph and considered responsible for their survival in the environment for millions of years. The efficacy of Achatina CRP (ACRP) was tested against both Salmonella typhimurium and Bacillus subtilis infections in mice where endogenous CRP level is negligible even after inflammatory stimulus. Further, growth curves of the bacteria revealed that ACRP (50 µg/mL) is bacteriostatic against gram negative salmonellae and bactericidal against gram positive bacilli. ACRP induced energy crises in bacterial cells, inhibited key carbohydrate metabolic enzymes such as phosphofructokinase in glycolysis, isocitrate dehydrogenase in TCA cycle, isocitrate lyase in glyoxylate cycle and fructose-1,6-bisphosphatase in gluconeogenesis. ACRP disturbed the homeostasis of cellular redox potential as well as reduced glutathione status, which is accompanied by an enhanced rate of lipid peroxidation. Annexin V-Cy3/CFDA dual staining clearly showed ACRP induced apoptosis-like death in bacterial cell population. Moreover, immunoblot analyses also indicated apoptosis-like death in ACRP treated bacterial cells, where activation of poly (ADP-ribose) polymerase-1 (PARP) and caspase-3 was noteworthy. It is concluded that metabolic impairment by ACRP in bacterial cells is primarily due to generation of reactive oxygen species and ACRP induced anti-bacterial effect is mediated by metabolic impairment leading to apoptosis-like death in bacterial cells.

Animals , Anti-Bacterial Agents/pharmacology , Apoptosis/drug effects , Bacillus subtilis/drug effects , Bacillus subtilis/metabolism , C-Reactive Protein/isolation & purification , C-Reactive Protein/pharmacology , Gluconeogenesis/drug effects , Glycolysis/drug effects , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/metabolism , Gram-Negative Bacterial Infections/microbiology , Hemolymph/metabolism , Homeostasis/drug effects , Immunoblotting , Lipid Peroxidation/drug effects , Male , Mice , Oxidation-Reduction , Reactive Oxygen Species/metabolism , Salmonella Infections/drug therapy , Salmonella Infections/metabolism , Salmonella Infections/microbiology , Salmonella typhimurium/drug effects , Salmonella typhimurium/metabolism , Snails
Applied Food Biotechnology. 2014; 1 (1): 45-54
in English | IMEMR | ID: emr-171607


Plant essential oils are natural products extracted from plants and because of their antimicrobial properties can be used as natural additives in foods. They are also useful for decontamination of food-borne pathogens and can be a safe additive in foods. The antimicrobial activities of essential oils belonging to Saturiea hortensis, Thymus vulgaris, Mentha polegium, Cuminum cyminum, Lavandula officinalis and Mentha viridis L. [spearmint] were investigated at different concentrations [0.1, 0.3, 0.5, 1, 2, 5 and 10%v/v] against Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B by using the agar well diffusion method. Essential oils showed inhibitory effect on Salmonella spp. in the agar well diffusion assay. In addition, the capability of essential oils for decontamination of minced row beef, ground beef, minced raw chicken and minced raw fish inoculated with Salmonella spp. at 0.1 and 0.5%v/v were assessed. Reduction of the Salmonella spp. population was observed following the inoculation of the cultures with 0.1 and 0.5%v/v essential oils

Salmonella typhimurium/drug effects , Salmonella paratyphi A/drug effects , Salmonella paratyphi B/drug effects , Anti-Infective Agents
Biomédica (Bogotá) ; 33(1): 78-87, ene.-mar. 2013. graf, tab
Article in Spanish | LILACS | ID: lil-675135


Introducción. La planta Solanum nudum es ampliamente usada en la medicina tradicional del Pacífico colombiano para tratar las fiebres y la malaria, o paludismo, y se ha convertido en una fuente de nuevas moléculas promisorias. Objetivo. Evaluar el efecto citotóxico y daño genético de extractos estandarizados de S. nudum en diferentes modelos celulares. Materiales y métodos. A 66 extractos estandarizados de S. nudum se les evaluó la actividad anti- Plasmodiumin vitro en dos cepas de Plasmodium falciparum, una sensible (NF54) y otra resistente (FCB2) a la cloroquina, y la citotoxicidad en células U937 y HepG2. Se seleccionaron los extractos que presentaron actividad anti- Plasmodium y baja toxicidad, y se les estimó su efecto hemolítico en eritrocitos sanos O + , el efecto mutagénico en las cepas TA98 y TA100 de Salmonella Typhimurium y el efecto genotóxico en células U937. Resultados. Se seleccionaron cinco extractos como promisorios (28MA1, 29MA1, 51MA1, 55MA1 y 61MA1), los cuales fueron activos en las cepas de P. falciparum con concentración inhibitoria 50 (CI 50 ) entre 9,8 y 54,8 µg/ml. El extracto 29MA1 fue el más selectivo para Plasmodium, con índice de selectividad de 4,4 y 14,5 para las células U937 y HepG2, respectivamente. En ningún extracto se observó efecto hemolítico a 250 µg/ml, no causaron mutaciones en las cepas TA98 y TA100 de S.Typhimurium, ni generaron efectos genotóxicos en células U937. Conclusiones. La utilización de extractos estandarizados de S. nudum contribuye con los trabajos encaminados al desarrollo de una nueva formulación farmacéutica para tratar la malaria a partir de productos naturales.

Introduction. The plant Solanum nudum (Solanaceae) is extensively used for the treatment of malaria-related symptoms in traditional medicine practices in the Colombian Pacific. Recently, it has become a significant source of promising new molecules for developing a pharmaceutical malaria treatment. Objective. This research aimed to evaluate the cytotoxic effect and the genetic damage of standardized extracts of S. nudumon different cells. Materials and methods. Sixty six standardized S. nudum extracts were used, evaluating cytotoxicity in U937 and HepG2 cells and the antiplasmodial activity using both a chloroquine-sensitive (NF54) and a chloroquine-resistant (FCB2) strain. The hemolytic effect on healthy O + erythrocytes, the mutagenic effect on S.Typhimurium TA98 and TA100 strains and the genotoxic effect on U937 cells were evaluated. The extracts that displayed both antiplasmodial activity and low toxicity were selected. Results. Five extracts were selected: 28MA1, 29MA1, 51MA1, 55MA1 and 61MA1. These extracts were active against P. falciparum with IC 50 between 9.8 and 54.8 µg/ml and selectivity indexes were calculated between 0.9 and 4.4, the latter for 29MA1. Also, no hemolytic effects in healthy O + erythrocytes were shown at a concentration of 250 µg/ml, nor did they cause mutations in the TA98 and TA100 strains or generate genotoxic effects in U937cells. Conclusion. The use of standardized extracts of S. nudum could contribute to the body of work aimed at developing a new pharmaceutical treatment for malaria using natural products.

Humans , Antimalarials/toxicity , Plant Extracts/toxicity , Plasmodium falciparum/drug effects , Solanum/chemistry , Antimalarials/isolation & purification , Antimalarials/pharmacology , Biotransformation , Chloroquine/pharmacology , DNA Damage , DNA, Bacterial/drug effects , Drug Evaluation, Preclinical , Drug Resistance , Erythrocytes/drug effects , Hemolysis/drug effects , /drug effects , Medicine, Traditional , Mutagenicity Tests , Phytotherapy , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Solvents , Salmonella typhimurium/drug effects , /drug effects
Article in English | LILACS | ID: lil-612949


Objetivo. Describir la prevalencia y la resistencia a los antibióticos de Salmonella spp. en canales de pollo congeladas de venta al por menor en 15 ciudades del Brasil. Métodos. Entre septiembre del 2004 y julio del 2006 se llevó a cabo un estudio descriptivo de los datos del Programa Nacional Brasileño de Vigilancia de la Prevalenciade la Resistencia Bacteriana en el Pollo (PREBAF). Durante el programa serecolectaron canales de pollo en 15 capitales estatales del Brasil, en las cinco regiones geográficas del país. Para aislar Salmonella spp. e identificar los serotipos, se usaron las técnicas convencionales. Para evaluar la resistencia frente a 18 antibióticos, se usó el método de la concentración inhibitoria mínima. Resultados. En las 2 679 canales de pollo examinadas, la prevalencia de Salmonella spp. fue de 2,7% (amplitud, 0,0%–8,9%). El 50,6% de las muestras positivas provinieron del estado de São Paulo. Se identificaron 18 serotipos. Los más frecuentes fueron Salmonella Enteritidis (48,8%), Salmonella Infantis (7,6%), Salmonella Typhimurium (7,2%) y Salmonella Heidelberg (6,4%). Las 250 cepas evaluadas fueron resistentes auno o más antibióticos, y 133 (53,2%) fueron multirresistentes (≥ 3 clases de antibióticos). Salmonella Heidelberg fue resistente a la ceftriaxona (75,0%) y al ceftiofur (43,8%). Conclusiones. La prevalencia de Salmonella spp. en este estudio fue relativamente baja. Sin embargo, hubo una proporción elevada de cepas multirresistentes, inclusivea las cefalosporinas de tercera generación usadas para tratar la salmonelosis invasora. Los resultados confirman la relevancia del programa PREBAF, el cual se recomienda mejorar, por ejemplo, mediante un análisis oportuno de los datos. También es necesario revisar los límites permitidos de Salmonella spp. en el pollo que se vende al por menor en el Brasil.

Objective. To describe the prevalence and antimicrobial resistance of Salmonella spp. in frozen chicken carcasses at retail from 15 Brazilian cities. Methods. A descriptive study of data from the Brazilian National Program for Monitoring the Prevalence of Bacterial Resistance in Chicken (PREBAF) was conducted from September 2004 to July 2006. The program collected chicken carcasses in 15 state capitals of Brazil inthe five geographic regions of the country. Standardized methodologies were used to isolate Salmonella spp. and identify serotypes. The minimal inhibitory concentration method wasused to test resistance to 18 antimicrobials. Results. In 2 679 carcasses examined, the prevalence of Salmonella spp. was 2.7% (range0.0%–8.9%). São Paulo State produced 50.6% of positive samples. Eighteen serotypes were identified. The most frequently occurring were Salmonella Enteritidis (48.8%), Salmonella Infantis (7.6%), Salmonella Typhimurium (7.2%), and Salmonella Heidelberg (6.4%). All 250 strains tested were resistant to one or more antibiotics, and 133 (53.2%) were multidrug resistant (≥ 3 classes). S. Heidelberg was resistant to ceftriaxone (75.0%) and to ceftiofur (43.8%).Conclusions. The prevalence of Salmonella spp. found in this study was relatively low. However, there were a high proportion of multidrug-resistant strains, including thirdgenerationcephalosporins used to treat invasive salmonellosis. The results confirm the relevance of the PREBAF program. It is recommended that PREBAF be improved, including a timely data analysis. A review of permitted limits for Salmonella spp. in retail chicken in Brazil is also needed.

Animals , Anti-Bacterial Agents/pharmacology , Chickens/microbiology , Drug Resistance, Microbial , Drug Resistance, Multiple, Bacterial , Food Contamination , Food Microbiology , Frozen Foods/microbiology , Meat/microbiology , Salmonella/isolation & purification , Brazil , Cryopreservation , Food Preservation , Microbial Sensitivity Tests , Sampling Studies , Serotyping , Salmonella Food Poisoning/prevention & control , Salmonella enteritidis/drug effects , Salmonella enteritidis/isolation & purification , Salmonella typhimurium/drug effects , Salmonella typhimurium/isolation & purification , Salmonella/classification , Salmonella/drug effects , Urban Health
Article in Spanish | LILACS | ID: lil-612950


The serotypes of 178 isolates of Salmonella enterica taken from food in different regions of Cuba between January 2008 and December 2009 were identified, and the antimicrobial susceptibility pattern of 100 selected isolates was determined by stratasampling. A total of 20 Salmonella serotypes were identified, with a predominance of S. Enteritidis (23%), S. Agona (13.5%), and S. London (11.2%). Of all the strains, 75%were resistant or presented intermediate resistance to at least one of the drugs tested, in the following order: tetracycline (70.7%), ampicillin (22.7%), and nalidixic acid (14.7%). Ten different resistance patterns were identified. The most frequent patternscorresponded to strains that were either drug-resistant or had intermediate resistance (89.3%). Three strains (identified as S. Infantis, S. Derby, and S. Enteritidis) were multiresistant, and one of them, S. Enteritidis, was not sensitive to either nalidixic acid or ciprofloxacin. To control salmonellosis, the importance of maximizing integrated health surveillance is emphasized.

Se describen los serotipos de 178 cepas de Salmonella enterica aisladas de alimentos en diferentes regiones de Cuba entre enero de 2008 y diciembre de 2009, y el patrón de susceptibilidada los antimicrobianos de 100 aislados seleccionados mediante muestreo por estratos. Se identificaron 20 serovariedades de Salmonella entre las que predominaron S. Enteritidis (23%);S. Agona (13,5%) y S. London (11,2%). Del total, 75% de las cepas fueron resistentes o presentaronresistencia intermedia a al menos uno de los fármacos probados, en el siguiente orden, según su frecuencia: tetraciclina (70,7%); ampicilina (22,7%) y ácido nalidíxico (14,7%). Seidentificaron 10 patrones de resistencia diferentes y predominaron las cepas resistentes o con resistencia intermedia a un fármaco (89,3%). Tres cepas (S. Infantis, S. Derby y S. Enteritidis)fueron multirresistentes y una, de S. Enteritidis, dio un resultado no sensible al ácido nalidíxico y la ciprofloxacina. Se destaca la necesidad de extremar la vigilancia sanitaria integrada en el país para el control de la salmonelosis.

Animals , Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial , Drug Resistance, Multiple, Bacterial , Food Contamination , Food Microbiology , Meat/microbiology , Salmonella/isolation & purification , Vegetables/microbiology , Cuba , Dairy Products/microbiology , Eggs/microbiology , Meat Products/microbiology , Serotyping , Salmonella Food Poisoning/prevention & control , Salmonella enteritidis/drug effects , Salmonella enteritidis/isolation & purification , Salmonella typhimurium/drug effects , Salmonella typhimurium/isolation & purification , Salmonella/classification , Salmonella/drug effects , Urban Health
Rev. panam. salud pública ; 29(6): 387-392, June 2011. tab
Article in English | LILACS | ID: lil-608267


OBJECTIVE: To determine the prevalence of resistance to ampicillin, chloramphenicol, streptomycin, sulphonamides, and tetracyclines (ACSSuT) in Salmonella serovar Typhimurium definitive [phage] type (DT) 193 strains isolated from human sources over the last four decades. METHODS: From 2008 to 2010, 553 DT193 isolates out of 810 human-origin Salmonella ser. Typhimurium phage-typed strains isolated from the 1970s through 2008 were selected and tested for ACSSuT resistance: 91 strains isolated during the 1970s, 65 from the 1980s, 70 from the 1990s, and 327 from 2000-2008. Resistance profiles were determined using the disk diffusion method. RESULTS: †An antimicrobial susceptibility assay indicated 20.9 percent, or 116, of all isolates tested were ACSSuT-resistant, 52.0 percent (287) were resistant to one or more drugs in the ACSSuT profile, and 27.1 percent (150) were nonresistant (susceptible to antimicrobials). Based on the assay, overall antimicrobial resistance was extremely high in the 1970s (affecting 99.0 percent of isolates from that period) and remained high during the 1980s, when 95.4 percent of isolates had some type of antimicrobial resistance and incidence of Salmonella ser. Typhimurium DT193 R-type ACSSuT increased to 73.8 percent. R-type ACSSuT dropped to 27.1 percent (19 isolates) during the 1990s, and to 5.2 percent (17) during 2000-2008, despite a substantial increase in the number of isolates tested (397 versus 204, 111, and 98, respectively, for the previous three decades). CONCLUSIONS: †Although prevalence of Salmonella ser. Typhimurium DT193 R-type ACSSuT in Brazil has decreased since the 1970s, ACSSuT resistance markers continue to circulate. Therefore, continuous surveillance should be conducted to evaluate the occurrence of Salmonella ser. Typhimurium DT193 and its antimicrobial resistance.

OBJETIVO: Determinar la prevalencia de resistencia a la ampicilina, el cloranfenicol, la estreptomicina, las sulfonamidas y las tetraciclinas (ACSSuT) en cepas de Salmonella serovariedad Typhimurium fagotipo definitivo (DT) 193 aisladas de fuentes de origen humano durante las cuatro últimas décadas. MÉTODOS: Entre el 2008 y el 2010 se seleccionaron 553 aislados de DT193 entre 810 cepas de Salmonella serovariedad Typhimurium fagotipificadas aisladas desde la década de 1970 hasta el 2008, y en ellos se analizó la resistencia a ACSSuT: se estudiaron 91 cepas aisladas durante la década de 1970, 65 aisladas durante la década de 1980, 70 aisladas durante la década de 1990, y 327 aisladas entre el 2000 y el 2008, respectivamente. Los perfiles de resistencia a los antibióticos se determinaron mediante el método de difusión en disco. RESULTADOS: El antibiograma indicó que 20,9 por ciento (116) de todos los aislados que se analizaron fueron resistentes a ACSSuT, 52,0 por ciento (287) fueron resistentes a uno o más antibióticos del grupo ACSSuT y 27,1 por ciento (150) no fueron resistentes (es decir, fueron sensibles a dichos antibióticos). Según el análisis, la resistencia general a los antibióticos fue muy alta en la década de 1970 (y comprendió a 99,0 por ciento de los aislados de ese período) y continuó siendo alta durante la década de 1980, cuando 95,4 por ciento de los aislados presentó algún tipo de resistencia a los antibióticos y la incidencia de Salmonella serovariedad Typhimurium DT193 con resistencia de tipo ACSSuT aumentó hasta 73,8 por ciento. La resistencia de tipo ACSSuT descendió a 27,1 por ciento (31 aislados) durante la década de 1990, y a 5,2 por ciento (17 aislados) entre el 2000 y el 2008, a pesar del aumento importante en el número de aislados que se evaluaron (397 frente a 204, 111 y 98 en las tres décadas anteriores, respectivamente). CONCLUSIONES: Aunque la prevalencia de Salmonella serovariedad Typhimurium DT193 con resistencia de tipo ACSSuT en el Brasil ha disminuido desde la década de 1970, los marcadores de resistencia a ACSSuT continúan en circulación. Por consiguiente, debe llevarse a cabo una vigilancia permanente para evaluar la aparición de infecciones por Salmonella serovariedad Typhimurium DT193 y su resistencia a los antibióticos.

Animals , Humans , Drug Resistance, Multiple, Bacterial , R Factors/genetics , Salmonella Infections/microbiology , Salmonella typhimurium/drug effects , Anti-Bacterial Agents/pharmacology , Bacteriophage Typing , Brazil/epidemiology , Drug Resistance, Multiple, Bacterial/genetics , Food Chain , Retrospective Studies , Serotyping , Salmonella Infections, Animal/microbiology , Salmonella Infections/drug therapy , Salmonella Infections/epidemiology , Salmonella typhimurium/classification , Salmonella typhimurium/genetics , Salmonella typhimurium/isolation & purification , Zoonoses
Braz. j. biol ; 71(1): 197-202, Feb. 2011. tab
Article in English | LILACS | ID: lil-578417


Although the use of medicinal plants or natural products has increased in recent decades all over the world, little information is available on their potential risk to health. Annona crassiflora Mart., a plant commonly known as araticum in Brazil, has been widely used in folk medicine for a long time since its seeds and leaves are often utilised in the treatment of cancer, snake bites, and venereal diseases, its fruits are consumed as tonic and astringent, and its bark powder has anti-fungal and anti-rheumatic properties. To evaluate the genotoxic and mutagenic properties induced by the ethanolic extract of araticum leaves, we performed the prophage λ induction (Inductest) and bacterial mutagenicity assays. We used Escherichia coli WP2s(λ) and RJF013 strains in the lysogenic induction test, whereas the mutagenic studies were carried out using Salmonella typhimurium histidine auxotroph strains TA97a, TA98, TA100, and TA102. Each experiment was performed three times in duplicate and included positive and negative controls. No statistically significant (p > 0.05) positive results were obtained for any of the strains tested, which suggests that the ethanolic extract of araticum leaves did not exhibit direct mechanisms of genotoxicity or mutagenicity that could be detected by the tests used in the present work.

Embora o uso de plantas medicinais ou de produtos naturais venha aumentando nas últimas décadas no mundo todo, existem poucas informações acerca de seu risco potencial para a saúde. Annona crassiflora Mart., uma planta comumente conhecida como araticum no Brasil, tem tido amplo uso em medicina popular há muito tempo, uma vez que suas sementes e folhas são frequentemente empregadas no tratamento de câncer, picadas de cobras e doenças venéreas, seus frutos são consumidos como tônico e adstringente, e o pó da casca de seu tronco apresenta propriedades antifúngicas e antirreumáticas. Para avaliar as propriedades genotóxica e mutagênica induzidas pelo extrato etanólico das folhas de araticum, utilizaram-se os testes de indução do profago λ (Induteste) e de mutagenicidade bacteriana. Foram empregadas as linhagens WP2s(λ) e RJF013 de Escherichia coli no teste de indução lisogênica, enquanto os estudos sobre mutagenicidade foram conduzidos utilizando as linhagens auxotróficas para histidina TA97a, TA98, TA100 e TA102 de Salmonella typhimurium. Cada experimento foi executado três vezes em duplicata, incluindo controles positivo e negativo. Não foram obtidos resultados positivos estatisticamente significativos (p > 0,05) para quaisquer das linhagens testadas, o que sugere que o extrato etanólico das folhas de araticum não apresentou mecanismos diretos de genotoxicidade ou mutagenicidade que pudessem ser detectados pelos testes usados no presente estudo.

Annona/chemistry , Escherichia coli/drug effects , Mutagenicity Tests/methods , Plant Extracts/toxicity , Salmonella typhimurium/drug effects , DNA Damage/drug effects , DNA Damage/genetics , Escherichia coli/genetics , Prophages/drug effects , Prophages/genetics , SOS Response, Genetics/drug effects , SOS Response, Genetics/genetics , Salmonella typhimurium/genetics
Braz. j. med. biol. res ; 42(9): 816-823, Sept. 2009. tab
Article in English | LILACS | ID: lil-524313


Pueraria mirifica is a Thai phytoestrogen-rich herb traditionally used for the treatment of menopausal symptoms. Pueraria lobata is also a phytoestrogen-rich herb traditionally used in Japan, Korea and China for the treatment of hypertension and alcoholism. We evaluated the mutagenic and antimutagenic activity of the two plant extracts using the Ames test preincubation method plus or minus the rat liver mixture S9 for metabolic activation using Salmonella typhimurium strains TA98 and TA100 as indicator strains. The cytotoxicity of the two extracts to the two S. typhimurium indicators was evaluated before the mutagenic and antimutagenic tests. Both extracts at a final concentration of 2.5, 5, 10, or 20 mg/plate exhibited only mild cytotoxic effects. The plant extracts at the concentrations of 2.5, 5 and 10 mg/plate in the presence and absence of the S9 mixture were negative in the mutagenic Ames test. In contrast, both extracts were positive in the antimutagenic Ames test towards either one or both of the tested mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and benzo(a)pyrene. The absence of mutagenic and the presence of anti-mutagenic activities of the two plant extracts were confirmed in rec-assays and further supported by a micronucleus test where both plant extracts at doses up to 300 mg/kg body weight (equivalent to 16 g/kg body weight plant tuberous powder) failed to exhibit significant micronucleus formation in rats. The tests confirmed the non-mutagenic but reasonably antimutagenic activities of the two plant extracts, supporting their current use as safe dietary supplements and cosmetics.

Animals , Male , Rats , Antimutagenic Agents/pharmacology , Bacillus subtilis/drug effects , Liver/drug effects , Mutagens/toxicity , Plant Extracts/pharmacology , Pueraria/chemistry , Salmonella typhimurium/drug effects , Antimutagenic Agents/isolation & purification , Antimutagenic Agents/toxicity , Bacillus subtilis/genetics , Micronucleus Tests/methods , Mutagens/isolation & purification , Plant Extracts/toxicity , Rats, Sprague-Dawley , Spectrophotometry , Salmonella typhimurium/genetics , Time Factors
Indian J Pediatr ; 2009 June; 76(6): 629-633
Article in English | IMSEAR | ID: sea-142301


Objective. To analyze an outbreak caused by a multipl resistant strain of S. typhimurium in a newborn unit in Turkey. Methods. The outbreak occured during the period 15 to 29 March,2005. A newborn infected with S. typhimurium was defined as a case. Newborns who were hospitalized during the outbreak period with no diagnosis of S. typhimurium infections (n=50) constituted the control group I (CG I). The matched patients of the control group II (CG II) (n=20) were selected from neonates without S. typhimurium infections during the period. Results. Of 22 infants who were affected two died. Cases developed diarrhea (n=20), septicemia (n=5) and meningtis (n=1). The strain was resistant to ampicillin, ceftriaxone, ceftazidime, amikacin, trimethoprim-sulfamethoxasole and chloromphenicol, susceptible to meropenem. All of the infected neonates were treated with meropenem. The surveillance cultures were negative. The outbreak was controlled by approprite therapy and institution of effective control measures. The cases were more exposed to mechanical ventilation than CG I (p<0.05). The mean additional length of stay in cases was significantly different from CG II (14.9 days vs. 5.1 days, p<0.05). The mean charges was $1588.78 for a case and $506.94 for a control (P<0.05). Accommodation accounted for 44.5% of these extra charges. Conclusion. This study increases the understanding of the burden of multidrug-resistant S. typhimurium infection. Nosocomial outbreaks have a major effect on healthcare delivery, costs and outcomes.

Anti-Bacterial Agents/therapeutic use , Cross Infection/drug therapy , Cross Infection/epidemiology , Disease Outbreaks , Drug Resistance, Multiple, Bacterial , Female , Humans , Infant, Newborn , Intensive Care Units, Neonatal/statistics & numerical data , Length of Stay , Male , Salmonella Infections/drug therapy , Salmonella Infections/economics , Salmonella Infections/epidemiology , Salmonella typhimurium/drug effects , Treatment Outcome , Turkey/epidemiology
Article in English | IMSEAR | ID: sea-19134


BACKGROUND & OBJECTIVE: Previous studies on natural products had mainly dealt with their antimicrobial activity and studies on the interference of these bioactive compounds with host-bacterial interaction is limited. The present study was undertaken to investigate the effect of the sterols and fatty acids present in the chloroform fraction of crude methanol extract of Hemidesmus indicus root (CHI) on Salmonella enterica serovar Typhimurium (S. Typhimurium) mediated apoptosis in a murine macrophage cell line (P388D1). METHODS: Bacterial sensitivity test was carried out with different concentrations of CHI and the optimum dose was fixed as 100 mug/ml for CHI, which was safe on host cells as the CD(50) (50% of cell death) dose of CHI was determined to be 500 mug/ml in the P388D1 cell line. RESULTS: The CHI-treated bacteria had negligible cytotoxicity and were less potent to invade and proliferate intracellularly. Murine macrophages infected with wild bacteria, stained with Hoechst 33258, had swollen and damaged morphology with characteristic apoptotic bodies whereas macrophages infected with treated bacteria had comparative normal architecture. Immunofluorescence and transmission electron micrographs both confirmed that CHI-treated bacteria were defective and smaller than the wild bacteria. Ultrastructures of P388D1 cells infected with wild bacteria showed many ingested bacteria and characteristic Salmonella-containing vacuoles (SCV). Some cells had condensed or fragmented nuclei with swollen mitochondria, whereas most of the cells infected with treated bacteria were normal in morphology and a few had internalized bacteria, but the typical bacteria laden SCV was not observed in cells infected with CHI-treated S. Typhimurium. INTERPRETATION & CONCLUSION: Our results showed that the choloroform fraction of H. indicus root blocked the cytotoxic activity of S. Typhimurium in a macrophage cell line. More studies need to be done to elaborate and confirm our findings.

Animals , Apoptosis/drug effects , Cell Line , Cell Proliferation/drug effects , Hemidesmus , Macrophages/microbiology , Mice , Plant Extracts/pharmacology , Plant Roots , Salmonella typhimurium/drug effects , Virulence
Article in English | IMSEAR | ID: sea-35363


A total of 138 isolates of S. Typhimurium and S. 4,[5],12:i:- from humans and swine in Thailand during 2003-2006, were evaluated for antimicrobial sensitivity by the disk diffusion method against 10 antimicrobial drugs and pulsed-field gel electrophoresis (PFGE) with endonuclease Xbal to investigate the epidemiological relationship among isolates. It was found that all isolates were classified into 27 antimicrobial resistance patterns, and 80% of S. Typhimurium and 95.4% of S. 4,[5],12:i:- isolates were resistant to three or more antimicrobial agents. By PFGE testing, the 84 PFGE patterns were categorized into A to Z patterns. Eighty percent of S. Typhimurium and 71.3% of S. 4,[5],12:i:- isolates in 7 major PFGE patterns had close clonal relationships (_85% similarity). Our studies indicate the spread of genetically identical clones of S. Typhimurium and S. 4,[5],12:i:- in humans and swine in Thailand.

Animals , Disease Reservoirs/microbiology , Electrophoresis, Gel, Pulsed-Field , Humans , Microbial Sensitivity Tests , Phylogeny , Population Surveillance , Salmonella enterica/drug effects , Salmonella typhimurium/drug effects , Sus scrofa/microbiology , Thailand/epidemiology
J Environ Biol ; 2007 Jan; 28(1): 123-6
Article in English | IMSEAR | ID: sea-113708


Sanganer town, district Jaipur (Rajasthan, India) is famous worldwide for its hand block dyeing and textile printing industries. These industries use a variety of chemicals and dyes during processing and finishing of raw materials. Most of the textile dyes used by these industries have not been evaluated for their impact on health and the environment. The workers in these industries are exposed to such dyes with no control over the length and frequency of exposure. Further, untreated and sometimes even treated effluents from these industries are released into surface waters of Amani Shah drainage or through the drainage systems, seep into the ground water and adjoining water bodies. Since many textile dyes are known carcinogens and mutagens, a complete evaluation of the safety of these dyes in the human environment must include an evaluation of their genotoxicity or mutagenicity. A total of 12 textile dyes from Sanganer were tested for their mutagenicity, by Ames Salmonella reversion assay using strain TA 100 of Salmonella typhimurium. Only 1 dye, Red 12 B showed absence of mutagenic activity. The remaining 11 dyes were all positively mutagenic.

Coloring Agents/toxicity , India , Mutagenicity Tests , Mutagens/toxicity , Salmonella typhimurium/drug effects , Textiles
Indian J Exp Biol ; 2006 Oct; 44(10): 838-41
Article in English | IMSEAR | ID: sea-61474


Ginseng has been reported to exhibit antioxidant and antimutagenic activity. The present study was undertaken with a view to confirm whether the antioxidant activity of Ginseng is responsible for its antimutagenic action. The concentrated root extract of Panax ginseng (Ginseng extract I) and its lyophilized powder (Ginseng extract II) obtained from two different manufacturing houses, were tested against mutagenesis using the well-standardized Ames microsomal test system. The extracts exhibited antimutagenic effect against hydrogen peroxide induced mutagenesis in TA100 strain, and against mutagenesis produced by 4-nitroquinoline-N-oxide in both TA98 and TA100 strains of Salmonella typhimurium. Both the extracts failed to show any antimutagenic potential against tert-butyl hydroperoxide (an oxidative mutagen) in TA102 strain, a strain highly sensitive to active oxygen species. The extracts also indicated a weak antioxidant activity in a series of in vitro test systems viz., 1,1-diphenyl picryl hydrazyl (DPPH) assay, hydrogen peroxide scavenging and superoxide anion scavenging. The results indicate that the protective effects shown by ginseng extract(s) against 4-nitroquinoline-n-oxide and hydrogen peroxide induced mutagenesis in TA98 and TA100 could mainly be due to its property to initiate and promote DNA repair rather than free radical scavenging action.

Antimutagenic Agents/pharmacology , Antioxidants/pharmacology , DNA Repair/drug effects , Free Radical Scavengers/pharmacology , Mutagenicity Tests , Panax , Plant Extracts/pharmacology , Salmonella typhimurium/drug effects
Southeast Asian J Trop Med Public Health ; 2006 ; 37 Suppl 3(): 195-202
Article in English | IMSEAR | ID: sea-33941


Mutagenicity and antimutagenicity potentials were tested using Ames' test in crude distilled water and absolute ethanol extracts from the stems and leaves of Peperomia pellucida (Linn.) Kunth, Eichhornia crassipes Solms, Colocasia esculenta Schott and Brachiaria mutica (Forssk.) Stapf, and the stems of Musa sapientum Linn. No mutagenic effect was found in any of the 10 mg/plate crude extracts of these plants for either TA98 or TA100 of Salmonella typhimurium, in a direct test and a mutagenic induced test by S-9 mix. Both distilled water and absolute ethanol extract of 0.5-10 mg/plate B. mutica showed strong antimutagenicity to AFB1, B(a)P and 4NQO in two tester strains. Ethanol extract of 0.1-0.5 mg/plate C. esculenta also showed antimutagenicity to AFB1, B(a)P and 4NQO in two tester strains, but the 0.5-10 mg/plate water extract had an antimutagenic effect only for B(a)P in TA98. The ethanol extracts of 5 mg/plate B. mutica and 0.5 mg/plate C. esculenta are cytotoxic, as indicated by their partial killing effect.

Animal Feed , Antimutagenic Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Medicine, Traditional , Mutagenicity Tests , Mutagens/pharmacology , Plants/chemistry , Salmonella typhimurium/drug effects , Thailand
Mem. Inst. Oswaldo Cruz ; 101(3): 281-286, May 2006. tab
Article in English | LILACS | ID: lil-431727


A total of 283 Salmonella Typhimurium strains isolated from cases of human infections and non human sources, were examined for antimicrobial susceptibilityand the incidence of resistance was 38 percent and multiple resistance (to three or more antimicrobials) was 15 percent. All 43 multidrug-resistant strains (MDR) and 13 susceptible ones were characterized by phage typing and pulsed- field gel electrophoresis (PFGE). The strains encompassed 14 definitive phage types (DT), three were untypable (UT), and 18 atypicals or reaction does not conform (RDNC), which belonged to 21 PFGE patterns, A1-A21. The predominant phage types were DT49, DT193, and RDNC and two strains belonging to DT 104 and 104b were also identified. The most commum PFGE patterns were A1 and A8. Analysis by PFGE and phage typing demonstrated that the most of the MDR were multiclonal and association among multiresistance, phage typing, and PFGE patterns was not so significant.

Humans , Anti-Bacterial Agents/pharmacology , Salmonella typhimurium/drug effects , Bacteriophage Typing/methods , Brazil , Electrophoresis, Gel, Pulsed-Field , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial , Salmonella typhimurium/classification