Antibacterial Activity of Lawsonia inermis Leaf Extracts against Multidrug-resistant Pseudomonas aeruginosa from Infected Wounds

Background: Wound infection comprises numerous different organisms that have the ability to surface colonization of wounds. Multidrug-resistant Pseudomonas aeruginosa is one of the pathogenic bacteria associated with wound infections. Aim: This study isolated and identified multidrug-resistant Pseudomonas aeruginosa from infected wounds and determine the antibacterial activity of Lawsonia inermis leaf extracts against it. Design: This is a Clinical and laboratory-based study involving patients with defined cases of wound infections. Place and Duration of Study: This study was conducted in the Microbiology (Bacteriology) laboratory of Specialist Hospital, Bauchi, Nigeria, from February to November 2021. Methods: Twenty-eight (28) Pseudomonas aeruginosa isolates were recovered from 179 wound swabs using standard laboratory procedures and were screened for multidrug-resistant patterns according to the Kirby-Bauer disc diffusion method. Antibacterial efficacy of the aqueous, ethanolic, and methanolic leaf extracts of Lawsonia inermis was tested against the multidrug-resistant isolates using agar well diffusion techniques. The zone of inhibition was measured and the differences between means were statistically analyzed (p<0.05). Results: A total of twenty-eight (28) multidrug-resistant Pseudomonas aeruginosa were confirmed, showing resistance to Amoxicillin (64.3%), Ceftazidime (85.71%), and Cefotaxime (78.57%) but sensitivity to Imipenem (95.5%). The phytochemical screening revealed the presence of flavonoids, glycosides, saponins, steroids, and tannins among others. MDR P. aeruginosa was inhibited at varied concentrations of the extracts with the diameter mean zone of inhibition increasing as the concentration increased. The Methanol extracts showed the highest antibacterial activity against MDR P. aeruginosa with a mean zone of inhibition of 9.500±0.288mm at 400mg/ml. Conclusion: These results indicated that Lawsonia inermis leaf extracts possess antibacterial activities on Multidrug-resistant Pseudomonas aeruginosa which could be a good source for the production of plant-based antibacterial drugs., although somewhat less than the synthetic standard drugs (Imipenem) having a mean of 13.83±0.288mm.

Synthesis of iron nanoparticles, its characterization and anti-microbial activity assessment

We report the efficacy of the Iron nanoparticles (IONPs) and assessed two different approaches for the synthesis of IONPs i.e. Polyol and co-precipitation method and further, evaluate their antimicrobial properties. Ferrous sulphate heptahydrate salts were reduced with ethylene glycol to obtain IONP and Fe+2 and Fe+3 co-precipitation reaction was performed with KOH at optimum heating. Further, synthesized (IONPs) were characterized by hydrodynamic radii measurement done by DLS clearly indicating the size of IONPs is 79.75nm in polyol based and 135.1 nm in co-precipitation method. The biological efficacy in terms of antimicrobial activity was assessed by the Kirby Bauer method, applied for both Gram-positive and Gram-negative bacteria such as Staphylococcus aureus and Escherichia coli, respectively. The ZOI values i.e. Zone of inhibition diameter was found to be clearly visible in both S. aureus and E. coli, indicating bactericidal activity. Further growth kinetics studies and bacterial genotoxicity was also assessed. Hence, IONPs synthesized are proposed to have great potential as an antibacterial agent and can be used in drug delivery.

Synthesis of Zinc Oxide Nanoparticles, its characterization and anti-microbial activity assessment

Zinc oxide nanoparticles (ZnO NPs) are one of the most abundant metal oxides nanoparticles. It provides excellent thermal, electrical and chemical stabilities with low biotoxicity; its photo-oxidising and photo-catalytic impact on biological and chemical species is of great importance, thereby making it a promising candidate to be used for in-vitro and in-vivo studies in biomedical field. Hereby, ZnO NPs were synthesized using precipitation method with zinc acetate and sodium hydroxide as starting materials. This study has characterized the synthesized ZnO NPs using different techniques such as UV-Visible spectroscopy indicating a peak at 365 nm wave length, size of ZnO NPs was determined to be 286.7 nm by measuring hydrodynamic radii using Dynamic Light Scattering (DLS) phenomena. Further predominant charge existing at surface of the synthesised ZnO NPs was evaluated to be 31.6mV. Anti-microbial activity of ZnO NPs was determined by Kirby-Bauer method for both Gram-positive and Gram-negative bacteria, S. aureus and E. colirespectively. Anti-microbial activity was determined as Zone of Inhibition that measures both bactericidal and bacteriostatic activity of ZnO NPs and was found to be more potent for Gram-positive (S. aureus)bacteria and its activity increased with increasing concentration of nanoparticles. Growth kinetics was studied to determine percentage growth inhibition, for this optical density was recorded as a function of time in bacterial culture broth with and without treatment. Further DNA fragmentation assay was performed to determine genotoxicity caused by nanoparticles and its effect on genomic DNA of bacteria. Highlighting its potential role as a nano-carrier system for leading antibacterial drugs for enhanced effectiveness of the antibacterial therapies

Isolation of Enterococcus spp. in various clinical sample and their antimicrobial resistant pattern with MIC of vancomycin in patient attending tertiary care centre, RIMS, Ranchi, Jharkhand

Introduction- Enterococci are part of normal intestinal flora of humans and animals but have also emerged as important pathogens responsible for serious infections in hospital and community acquired infections.it is second most common cause of nosocomial infections in gastrointestinal tract, wound and genitourinary tract. To process all the clinicalAim- samples from various department in our hospital, for isolation of Enterococci spp. To speciate the isolates & to have resistance pattern of the isolates of vancomycin total 926 sample were collected from both outMaterial & Methods- patients and in patient in all clinical departments and transported to microbiology laboratory. specimens were processed by inoculating on to blood agar, MacConkey Agar, nutrient agar, potassium tellurite agar and incubated at 37°C for24-48 hr. Enterococci were identified by their typical arrangement in and salt tolerance test Gram stain, bile esculin test and biochemical tests. Antimicrobial susceptibility patterns were determined by performing Kirby-Bauer disc diffusion method and Minimum inhibitory concentration (MIC) values were identified by tube dilution methods. Result- a total of 926 sample, 645 (69.72%) were culture positive and 281 (30.28%) were culture negative. Among 645 culture positive cases, 81(12.55%) were Enterococcus faecalis. Antimicrobial susceptibility & MIC done as per standard protocols. The E. Faecalis showed 99% sensitive to Vancomycin. the resistance to vancomycin was 1% & further confirmed by MIC via tube dilution methods. In which MIC was ?32 ?g/ml in one isolate. About 8 of Enterococcal strains showed MIC of 0.0125?g/ml. species level identification of Enterococcus is important forConclusions- epidemiological study and also for analysis of drug resistant pattern. Effective detection of vancomycin resistance helps in reducing the morbidity and mortality of VRE in hospitalized patients

Evaluación del efecto antibacteriano sinérgico de rifamicina en propóleo sobre bacterias grampositivas / Evaluation of the synergistic antibacterial effect of rifamycin in propolis on gram-positive bacteria

Introducción: En la medicina militar, la aplicación de las sustancias antibacterianas en las infecciones tópicas, es importante en el tratamiento de las tropas. Objetivos: Evaluar el efecto antibacteriano sinérgico de rifamicina en propóleo sobre bacterias grampositivas. Métodos: Estudio experimental in vitro y comparativo. Se efectuó el análisis fitoquímico preliminar del propóleo de Apis mellífera. Se utilizaron 96 placas de agar Muller Hinton (Britania®) (48 placas para cada especie bacteriana) repartidas en 6 grupos (n = 8). grupo I (agua destilada), grupo II (alcohol etílico al 96 por ciento), grupo III (rifamicina al 0,5 por ciento), grupo IV (rifamicina al 1 por ciento), grupo V (propóleo al 20 por ciento) y grupo VI (rifamicina al 1 por ciento en propóleo al 40 por ciento); se empleó la metodología de Kirby - Bauer; las cepas usadas fueron Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC 19615 y las mediciones de las zonas de inhibición se efectuaron a las 24 horas. Resultados: Se detectaron compuestos fenólicos, taninos, flavonoides, alcaloides y triterpenoides en propóleo. Se comprobó el efecto antibacteriano del grupo V con 18,627 ± 0,1008 mm (92,59 por ciento) y 19,247 ± 0,0762 mm (96,74 por ciento), y el efecto antibacteriano sinérgico del grupo VI con 19,316 ± 0,1202 mm (96,02 por ciento) y 19,613 ± 0,0820 mm (98,58 por ciento), comparados con rifamicina al 1 por ciento (100 por ciento) sobre S. aureus ATCC 25923 y S. pyogenes ATCC 19615. Conclusiones: La combinación de rifamicina al 1 por ciento unida al propóleo al 40 por ciento presenta una mayor actividad antibacteriana in vitro sobre bacterias grampositivas debido a su efecto sinérgico(AU)

Introduction: In military medicine, the application of antibacterial substances in topical infections are important in the treatment of troops. Objectives: To evaluate the synergistic antibacterial effect of rifamycin in propolis on gram-positive bacteria. Methods: In vitro and comparative experimental study. Preliminary phytochemical analysis of Apis mellifera propolis was carried out. 96 Muller Hinton agar plates (Britania®) (48 plates for each bacterial species) divided into 6 groups (n = 8) were used group I (distilled water), group II (96 percent ethyl alcohol), group III (rifamycin 0,5 percent), group IV (rifamycin 1 percent), group V (propolis 20 percent) and group VI (rifamycin 1 percent in 40 percent propolis); Kirby-Bauer methodology was used; the strains used were Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC 19615 and the measurements of the zones of inhibition were carried out at 24 hours. Results: Phenolic compounds, tannins, flavonoids, alkaloids and triterpenoids were detected in propolis. The antibacterial effect of group V was verified with 18,627 ± 0,1008 mm (92,59 percent) and 19,247 ± 0,0762 mm (96,74 percent), and the synergistic antibacterial effect of group VI with 19,316 ± 0,1202 mm (96,02 percent) and 19,613 ± 0,0820 mm (98,58 percent), compared with rifamycin 1 percent (100 percent) on S. aureus ATCC 25923 y S. pyogenes ATCC 19615. Conclusions: The combination of rifamycin 1 percent together with propolis 40 percent has a greater antibacterial activity in vitro on gram-positive bacteria due to its synergistic effect(AU)

Actividad antibacteriana y antifúngica del aceite esencial de Minthostachys mollis frente a microorganismos de la cavidad oral / Antibacterial and Antifungal Activity of the essential oil of Minthostachys mollis against oral microorganisms

Introducción: La Minthostachys mollises una planta aromática que crece en América Latina y produce aceites esenciales con acción antimicrobiana. Objetivo: Determinar la actividad del aceite esencial de Minthostachys mollis en diferentes concentraciones, comparado con doxiciclina y fluconazol frente a Porphyromonas gingivalis, Staphylococcus aureus y Candida albicans, a las 24, 48 y 72 horas. Métodos: Se realiza estudio experimental in vitro y longitudinal. Se prepararon 15 pocillos por subgrupo para evaluar el efecto inhibitorio de todas las concentraciones, dando un total de 360 pocillos. Por cromatografía de gases acoplada a espectrometría de masas se identificaron los componentes químicos del aceite esencial. Se analizó el efecto inhibitorio por el método de difusión de Kirby-Bauer en Agar Columbia y Agar Muller Hinton. El análisis estadístico se realizó mediante la prueba ANOVA y Tukey. Resultados: En el análisis químico se identificó principalmente pulegona (30,17 por ciento) y mentona (16,55 por ciento). Los halos de inhibición de Minthostachys mollis al 100 por ciento a las 24, 48 y 72 horas frente a la Porphyromonas gingivalis, midieron: 10,2 mm, 9,8 mm y 9,6 mm, respectivamente; frente al Staphylococcus aureus, midieron: 10,4 mm, 9,7 mm y 9,4 mm, respectivamente; y, por último, frente a Candida albicans midieron: 9,8 mm, 8,9 mm y 8,5 mm, respectivamente. Todas las concentraciones de Minthostachys mollis presentaron un efecto antimicrobiano significativamente menor que el fluconazol y la doxiciclina (p < 0,001). Conclusiones: El aceite esencial de Minthostachys mollis al 100 % presentó su mejor actividad inhibitoria frente al Staphylococcus aureus, la Porphyromonas gingivalis y la Candida albicans a las 24 horas. Sin embargo, este efecto antimicrobiano disminuye a medida que pasa el tiempo(AU)

Introduction: Minthostachys mollis is an aromatic plant species growing in Latin America which produces essential oils with antimicrobial activity. Objective: Determine the activity of essential oil from Minthostachys mollis at various concentrations as compared with doxycycline and fluconazole against Porphyromonas gingivalis, Staphylococcus aureus and Candida albicans at 24, 48 and 72 hours. Methods: An in vitro experimental longitudinal study was conducted. Fifteen wells were prepared per subgroup to evaluate the inhibitory effect of all concentrations, for a sum total of 360 wells. Chemical components of the essential oil were identified by gas chromatography-mass spectrometry. The inhibitory effect was analyzed with the Kirby-Bauer diffusion method in Mueller-Hinton and Columbia agar. Statistical analysis was based on ANOVA and Tukey's test. Results: Chemical analysis mainly found pulegone (30.17 percent) and menthone (16.55 percent). The inhibition halos of 100 percent Minthostachys mollis at 24, 48 and 72 hours against Porphyromonas gingivalis measured 10.2 mm, 9.8 mm and 9.6 mm, respectively, against Staphylococcus aureus they measured 10.4 mm, 9.7 mm and 9.4 mm, respectively, and against Candida albicans they measured 9.8 mm, 8.9 mm and 8.5 mm, respectively. The antimicrobial effect of Minthostachys mollis at all concentrations was significantly lower than that of fluconazole and doxycycline (p < 0.001). Conclusions: The essential oil from 100% Minthostachys mollis displayed its best inhibitory activity against Staphylococcus aureus, Porphyromonas gingivalis and Candida albicans at 24 hours. However, such antimicrobial effect decreases with the passing of time(AU)

Neonatal Sepsis is Still a Major Problem in Tertiary Care Hospitals.

In a developing country like India, one of the most important health hazards is neonatal sepsis. The ever full SNCUs of the hospitals are living proof of this. The neonates both early and late are extremely vulnerable to all organisms, both in the community and much more so in the hospital. Neonatal sepsis contributes to infant mortality rate in a very significant way. Nosocomial neonatal sepsis is much more dangerous and contributes to morbidity and mortality in a very big way.METHODSIn this study, neonatal sepsis was assessed by culture of blood, pus from infected umbilical stump, and CSF sample received from SNCU. The isolated organisms were identified phenotypically following our laboratory protocol. Antibiotic sensitivity testing was done by Kirby-Bauer method, following CLSI guidelines.RESULTSIt was found that 48% of the total samples received from SNCU were growth positive. Klebsiella pneumoniae was isolated in maximum number of cases, 42.85% followed by Staphylococcus aureus 18.53%. Antibiotic sensitivity test by Kirby- Bauer method showed that all Gram-positive cocci were sensitive to vancomycin. There was only one linezolid resistant Staphylococcus aureus. Among the Gram-negative bacilli 100% isolates were sensitive to carbapenems. Acinetobacter baumannii and Pseudomonas aeruginosa isolates were multidrug resistant.CONCLUSIONSSNCU admitted babies are extremely vulnerable to septicaemia. The ever-changing drug resistant patterns of the infecting organisms is a perineal problem. Thus, infection control measures are to be strictly enforced in this setting.

Isolation, identification and antibiogram profiling of bacteria isolated from water, seafood, and macroplastic samples from Baseco Beach, Manila Bay

Background and Objective@#Manila Bay plays an important role both in economics and ecology because it serves as the major economic center of the Philippines and as it harbors different habitats and biodiversity. Unfortunately, it is threatened by various pollutions including the unregulated discharge of wastewater from industrial, agricultural, and household sectors and improper disposal of trash such as macroplastics among others. All these contributes to the current state of Manila Bay. This study identified bacteria isolated from water, seafood and floating macroplastic samples from Baseco Beach, Manila Bay and determined their antibiogram profiles. @*Methodology@#Bacterial isolates were obtained from water, seafoods and macroplastic samples from Baseco Beach, Manila Bay using conventional culture techniques. Identification of the isolates was done using Vitek-2 Automated System and antibiogram profiling was done using Kirby-Bauer Disk Diffusion Susceptibility Test. @*Results and Conclusions@#A total of 30 bacterial isolates were obtained from different samples from water, seafood and macroplastic samples from Baseco Beach, Manila Bay. These isolates were identified and found to belong to 13 different bacterial species with Bacillus spp. comprising 33.33% of the isolates (10 out of 30), and Vibrio alginolyticus comprising 23.33% of the isolates (7 out of 30) and the other species comprise the remaining 43.34% (Pseudomonas spp., Vibrio fluvialis, Klebsiella pneumoniae, Shewanella alga, Sphingomonas paucimobilis, Staphylococcus haemolyticus, Chryseobacterium indologenes, Myroides sp. and Aeromonas salmonicida). Of these, six out of 30 isolates (20%) showed susceptibility to all six representative antibiotics used (Cefazolin 30μg, Gentamicin 10 μg, Chloramphenicol 30 μg, ampicillin 10 μg, Cefuroxime 30 μg, Ceftazidime 30 μg) while 7 isolates (23.33%) were resistant to only one class of antibiotic. Moreover, 17 out of 30 isolates (56.66%) were resistant to two or more classes of antibiotic while only one isolate (3.33%) was found to be resistant to gentamicin. All 30 isolates (100%) were susceptible to chloramphenicol. Interestingly, three antibiotic resistant (AMR) bacteria were isolated from macroplastics namely Pseudomonas oleovorans (S2), Vibrio alginolyticus (S5), and Pseudomonas alcaligenes (S29) which were all resistant to ampicillin and cefazolin. This is the first study in the Philippines to isolate AMR bacteria from macroplastics from Manila Bay. The presence of AMR bacteria in macroplastics shows that these materials can be a reservoir for its dynamics and distribution. Lastly, with the emergence of antimicrobial resistant bacteria, the elucidation of the antibiogram profile of bacteria is necessary to determine its implication sand threats to public health. This study served as a baseline study of presence of AMR bacteria in macroplastic samples from Manila Bay.

Prevalence of antibiotic resistant bacteria isolated from raw chicken meat

Aims@#Antibiotics are widely used in poultry industry for treatment, control and in preventing the spread of infectious diseases among chicken flocks. The uncontrolled use of antibiotic causes the emergence of antibiotic resistant bacteria which is a major concern worldwide. The aim of this study is to isolate and molecularly identify antibiotic resistant bacteria using raw chicken meat samples from farm, supermarket, wet market as well as free-range chicken. @*Methodology and results@#A total of 34 isolates were obtained through primary screening based on their ability to grow on streptomycin, kanamycin, ampicillin and cefazolin antibiotic plates. Kirby-Bauer disc diffusion test performed on the 34 isolates showed that they were highly resistant to oxacillin (97%) and penicillin (94%) followed by ampicillin (64%), cefazolin (50%), tetracycline (32%), erythromycin (24%), ciprofloxacin (21%) and least resistance towards gentamycin (6%). Eight isolates with the highest antibiotic resistance, were selected for molecular identification using 16S rDNA sequencing. Analysis of the 16S rDNA sequence using BLASTN and phylogenetic tree constructed on the selected isolates revealed that five different species of antibiotic resistant bacteria namely Escherichia coli, Klebsiella sp., Chryseobacterium gleum, Comamonas testosteroni and Bacillus cereus were successfully identified from the different types of chicken sample.@*Conclusion, significance and impact of study@#The excessive use of antibiotic in the poultry farm industries had caused the emergence of antibiotic resistant bacteria which can harm the health of people consuming chicken meat. To overcome this crisis, antibiotic usage in the poultry farm industries should be regulated.

Antimicrobial sensitivity pattern from clinical isolates at a tertiary care teaching hospital of rural Bengal: a pilot study

Background: Antimicrobial sensitivity pattern from clinical isolates can reveal important information that can help in drafting the hospital antibiotic policy as well as help improve prescribing patterns and patient outcome in a particular region.Methods: Data from the results of the antimicrobial sensitivity pattern of clinical isolates of the patients between 1stJuly and 31st December 2018 were collected on a pre-designed and pre tested case study form and analysed with the help of descriptive statistics.Results: A total of 75 blood culture reports were obtained which showed 58 gram positive cultures. Further 46 of the gram positive samples were positive for Coagulase negative Staphylococcus. A total of 305 urine samples were obtained for culture which showed gram negative cultures. Paediatric and medicine wards were the common yielding sites. A total of 242 pus reports were obtained which showed 47 gram positive cultures. A total of 154 wound swab samples were obtained which showed 47 gram positive cultures. For pus and wound swab samples, surgery wards were the common yielding sites. Common gram negative organisms seen were Klebsiella sp., E. coli, Citrobacter sp., Pseudomonas, Proteus and Enterobacter. Gram positive organisms were commonly resistant to Erythromycin, orally active Penicillins, Vancomycin and Teicoplanin and gram negative organisms were commonly resistant to Cephalosporins, Aminoglycosides, Colistin, Fluroquinolones and Meropenem.Conclusions: This study showed that over six months samples of body pus, wound swab, blood culture and urine showed high levels of resistance to commonly used antibiotics. This would provide an outline for development of an effective hospital Infection Control Policy.

Antibacterial activity of silver nanoparticles immobilized in zinc oxide-eugenol cement against Enterococcus faecalis: an in vitro study / Actividad antibacteriana de nanopartículas de plata inmovilizadas en cemento de óxido de zinc-eugenol contra el Enterococcus faecalis: estudio in vitro

ABSTRACT Introduction: the aim of this study is to evaluate the antimicrobial capacity of silver nanoparticles immobilized in a zinc oxide-eugenol (ZOE) cement against Enterococcus faecalis for potential use in endodontic treatments. Method: experimental in vitro study, performing synthesis of silver nanoparticles (AgNPs) and UV-visible spectroscopy to confirm presence of AgNPs in the prepared solutions. The ZOE mixture was standardized, producing the integrated AgNPs/ZOE material. Scanning electron microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR) were used to characterize the integrated material; a Kirby- Bauer assay was finally run to measure the inhibition halos produced by the compound-microorganism interaction. Results: the UV-visible spectroscopy showed presence of AgNPs in the created solution; both SEM and FTIR show that the AgNPs are integrated into the ZOE system, not altering their properties when performed under conditions like those found in the mouth. The Kirby-Bauer assay shows that all samples had inhibition halos. The AgNPs in guava extract had statistically significant differences with the halos of the other samples (p < 0.05). Conclusions: the obtained AgNPs show bactericidal activity against Enterococcus faecalis, as a statistically significant difference was found between the AgNPs suspended in guava extract and the other groups; this will be the starting point for future research.

RESUMEN Introducción: el propósito de este estudio es evaluar la capacidad antimicrobiana de las nanopartículas de plata inmovilizadas en un cemento de óxido de zinc-eugenol (OZE) contra el Enterococcus faecalis para su potencial uso en tratamientos endodónticos. Método: se utilizó un diseño experimental in vitro. Se realizó la síntesis de nanopartículas de plata (NPsAg), se efectuó espectroscopía UV-visible para confirmar que las soluciones preparadas contaran con la presencia de NPsAg, se estandarizó la mezcla de OZE y posteriormente se generó el material integrado de NPsAg y OZE. Para la caracterización del material integrado se utilizó microscopía electrónica de barrido (SEM) y espectroscopía infrarroja transformada de Fourier (FTIR), posteriormente se ejecutó el ensayo Kirby-Bauer para medir los halos de inhibición generados de la interacción compuesto-microorganismo. Resultados: la espectroscopía UV-visible arrojó que en la solución creada hay presencia de NPsAg; el SEM y la FTIR muestran que las NPsAg se integran en el sistema OZE y no alteran sus propiedades cuando se realizan en condiciones similares a las que se encuentran en la boca. El ensayo Kirby-Bauer revela que todas las muestras presentaron halo de inhibición; las NPsAg en suspensión de extracto de guayaba presentan diferencias estadísticamente significativas con los halos de las demás muestras (p < 0.05). Conclusiones: las NPsAg obtenidas presentan actividad bactericida contra el Enterococcus faecalis, al encontrar diferencia estadísticamente significativa entre las NPsAg en suspensión en extracto de guayaba con los demás grupos. Este será el punto de partida para futuras investigaciones.

Evaluación del efecto antibacteriano del látex de Jatropha curcas "piñón" frente a Staphylococcus aureus / Evaluation of the antibacterial effect of latex Jatropha curcas "piñón" in front of Staphylococcus aureus

La presente investigación tuvo como objetivo evaluar el efecto antibacteriano del látex de Jatropha Curcas "Piñón" frente a Staphylococcus aureus. El método de difusión en disco, de Kirby Bauer, fue usado en la investigación; las concentraciones del látex de Jatropha Curcas "Piñón" fueron las siguientes: 10%, 20%, 30%, 40% y 100% usando agua destilada como solvente. Se realizó análisis fitoquímico y prueba de solubilidad al látex de la planta en estudio. El látex de Jatropha Curcas "Piñón" fue muy soluble en agua destilada, etanol y metanol; además, según el análisis fitoquímico, el látex presentó flavonoides, taninos, compuestos fenólicos, alcaloides y esteroides. La concentración del látex al 40% presentó el mayor efecto antibacteriano a un nivel de confianza del 95%, y un error relativo del 5%.

The present research aims to evaluate the antibacterial effect of Jatropha Curcas latex "Piñón" against Staphylococcus aureus. The disc diffusion method of Kirby Bauer was used in the research, the concentrations of Jatropha Curcas "Piñón" latex were as follows: 10%, 20%, 30%, 40% and 100% using distilled water as solvent. Phytochemical analysis and solubility test were performed on the latex of the plant under study. Jatropha Curcas "Piñón" latex was very soluble in distilled water, ethanol and methanol. According to the phytochemical analysis the latex presented flavonoids, tannins, phenolic compounds, alkaloids and steroids. The concentration of latex at 40% had the highest antibacterial effect at a 95% confidence level and a relative error of 5%.

Correction of Kirby-Bauer disc diffusion assay to the errors of automated ampicillin susceptibility test for Hemophilus influenzae / 国际检验医学杂志

Objective Broth dilution method was used as a reference method to observe the capability of Kirby-Bauer disc diffusion assay(K-B)for correcting automated ampicillin susceptibility detection of He-mophilus influenzae(HI).Methods A total of 228 HI strains isolated were collected,broth dilution assay,K-B and automated microdilution broth test(ATB)were used to determine the susceptibility of HI to ampicillin. Analyze the essential agreements of the three methods and the correction of K-B to the errors of A TB. Results The essential agreement of K-B or ATB with broth dilution method were 77.19%,70.18% respec-tively,combination of K-B and ATB could make the essential agreement increase up to 86.0%,which was sig-nificantly higher than ATB(χ2=16.600,P=0.000).Major error of ATB(42.0%)was higher than that of K-B(10.0%)(χ2=13.306,P=0.001),but very major error and minor error showed no significant difference be-tween the two methods(χ2=1.208,P=0.272;χ2=1.182,P=0.227),meanwhile,76.19% of major error of ATB could be corrected by K-B.For the very major error of ATB,53.57% could be corrected by K-B.Howev-er,the corrective capability of K-B to minor error of ATB was relative low.Conclusion K-B test could correct some errors generated by ATB.For the β-lactamase negative strains which were judged as ampicillin resistance by A TB,K-B test should be used to correct the errors by ATB.Moreover,it is necessary to apply K-B to confirm am-picillin sensitivity of the β-lactamase positive strains which were judged as ampicillin susceptible by ATB.

Susceptibility of Acinetobacter baumannii isolates to eight antimicrobial agents tested by different methods / 中国感染与化疗杂志

Objective The purpose of this study was to analyze the susceptibility profile of Acinetobacter baumannii to antimicrobial agents,and validate the results of different antimicrobial susceptibility testing methods,for improving the quality of antibiotic resistance monitoring data.Methods The susceptibility data of Hebei Provincial Antimicrobial Resistant Investigation Net were analyzed retrospectively and 126 strains ofA.baumannii were collected.The susceptibility ofA.baumannii to piperacillintazobactam,amikacin,gentamicin,ciprofloxacin,levofloxacin,ceftazidime,imipenem,and meropenem was tested by E-test,KirbyBauer method and VITEK system.Results The susceptibility results of the 126 A.baumannii strains showed that the susceptibility to piperacillin-tazobactam,amikacin,gentamicin,levofloxacin and ceftazidime was significantly different between the three methods (P＜0.05).The categorical agreement,major error,minor error,and very major error of Kirby-Bauer method were within acceptable range.There were evident difference in classification consistency for piperacillin-tazobactam,amikacin,levofloxacin between Kirby-Bauer method and VITEK (P＜0.05).Conclusions Different antimicrobial susceptibility testing methods may lead to different results of resistance monitoring data.Bias may be generated in antibiotic resistance surveillance if different methods are used.The susceptibility results of piperacillin-tazobactam,amikacin,levofloxacin derived from VITEK system should be validated by Kirby-Bauer or E-test method.

Incidence of carbapenem resistant nonfermenting gram negative bacilli from patients with respiratory tract infections among intensive care units.

Background: Non fermenting gram negative bacilli that were considered to be contaminants in the past have now emerged as important healthcare- associated pathogens. Pseudomonas aeruginosa and Acinetobacter species are now known to be the common nosocomial pathogens. Carbapenems are one of the essential antibiotics in the armamentarium against, serious nosocomial infections. Development of resistance against these is a cause of concern. Misuse and inappropriate duration of antibiotic therapy helps in development of resistance. Methods: A total of 200 endo tracheal aspirates and sputum samples were collected from patients of all age groups with clinical evidence of lower respiratory tract infection from Medical, surgical, pediatric ICUS. Non fermenting gram negative bacilli isolated and identified according to CLSI guidelines and antibiotic sensitivity test was performed by Kirby Bauer disc diffusion method. Results: Out of 200 samples 50 Acinetobacter spp. and 38 Pseudomonas aeruginosa were isolated. Among 38 Pseudomonas isolates (42%) 16 were resistant to imipenem and 11 (29%) were resistant to meropenem. Among 50 Acinetobacter isolates 14 (28%) were resistant to imipenem and 12 (24%) were resistant to meropenem. Conclusions: Our study documents an increase in the carbapenem resistance. Reduction in antimicrobial resistance in the ICUS has been a goal for all ICUS as it improves outcome and cost of patient care. Carbapenem must be used judiciously to prevent further resistance or else this would erode the strength of life saving antibiotics.

Comparative Study of the Antibacterial Effect of Mouth Washes and Vernonia amygdalina (del.) on Some Tooth Decay Causing Bacteria.

Aims: To determine the antibacterial effect of the ethanol stem extract of Vernonia amygdalina (bitter-leaf) and some mouth washes against some bacteria that have been implicated in causing tooth decay so as to establish the role of herbal medicine and chemical compounds in oral hygiene. Study Design: In vitro assay of antibacterial activities Place and Duration of Study: Dental Department of the State Specialist Hospital, Akure, Ondo State, Nigeria and Department of Microbiology, Federal University of Technology, Akure, Nigeria, between October, 2012 and January, 2013. Methodology: Bacterial isolates were collected, identified, standardized and the stem extract was prepared. Phytochemical screening of the extracts was carried out as well as the in vitro antibacterial assay using agar well diffusion technique. Minimum Inhibitory Concentration and antibiotics sensitivity test (disc diffusion assay) were also determined. Results: The stem extract showed the presence of anthraquinone, alkaloid, saponin, steroid and cardiac glycoside. The ethanolic stem extract of Vernonia amygdalina inhibited all the test isolates at a concentration of 50 mg/ml with the highest zone of inhibition observed against Staphylococcus aureus (26.0 mm) while the least zone of inhibition of 14.0 mm was observed against Streptococcus mutans. Colgate mouthwash exhibited the highest zone of inhibition against Staphylococcus aureus while the least was recorded by Brett against Staphylococcus epidermidis. The antibacterial assay compared well with Ciprofloxacin, and in most cases higher zones of inhibition were recorded than the commercial antibiotics. The Minimum Inhibitory Concentration of the mouth washes ranged from 30 to 70% while it was 12.5 mg/ml for the stem extract. Conclusion: Bioactive components of Vernonia amygdalina can be incorporated as ingredients in manufacturing mouthwashes and the plants’ stem can be used in the form of chewing stick. Further purification of the extract is necessary to further enhance greater antibacterial activity.

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

<p><b>OBJECTIVE</b>To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA).</p><p><b>METHODS</b>Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.</p><p><b>RESULTS</b>Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key.</p><p><b>CONCLUSIONS</b>The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.</p>

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

Objective: To investigate the antibacterial activity of marine actinobacteria against Multidrug resistance Staphylococcus aureus (MDRSA). Methods: Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey’s manual of Determinative Bacteriology. Results: Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1000μg/ml. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key. Conclusion: The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA). Methods: Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology. Results: Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 μg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key. Conclusions: The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.

Determinación de la prevalencia de betalactamasas de espectro extendido en pacientes con bacteremia por gramnegativos / Determination of the prevalence of extended spectrum beta-lactamase in patients with gram-negative bacteremia

Actualmente, el tratamiento de las infecciones bacterianas se ha hecho sumamente complicado, debido fundamentalmente al fenómeno de la resistencia bacteriana. Las bacterias poseen mecanismos que pueden hacerlas resistentes a los más novedosos antibióticos y muchos de nuestros pacientes no tienen la fortuna de sobrevivir a infecciones severas relacionadas con bacteremia. Existen varios mecanismos distintos de resistencia en bacterias gramnegativas. Quizás el mecanismo más importante de resistencia bacteriana sea la producción de betalactamasas y en la actualidad, un grupo de ellas ocupa un lugar preponderante con relación a este fenómeno: las betalactamasas de espectro extendido. Este estudio pretende demostrar la prevalencia de este mecanismo de resistencia en bacteremias ocasionadas por gramnegativos. Se evaluaron los hemocultivos procesados en el laboratorio de Microbiología del Hospital "J.M de Los Ríos" entre enero 2003 y diciembre 2006 que reportaron bacterias gramnegativas probables productoras de betalactamasas de espectro extendido y se reportó la susceptibilidad a los antibióticos. El gramnegativo aislado con mayor frecuencia fue Klebsiella pneumoniae (24,51 por ciento). De los 771 gramnegativos aislados, 268 (34,76 por ciento) eran probables productores de betalactamasas de espectro extendido, siendo Klebsiella pneumoniae el más frecuente (50 por ciento) y uno de los mayores productores de betalactamasas de espectro extendido (70,89 por ciento). Los patrones de resistencia fueron variables.