scholarly journals Evaluation of the antibacterial and modulatory activities of ethanolic excract of Calotropis procera (Aiton) W.T. Aiton against multiresistant bacterial strains

2021 ◽  
pp. 205-209
Author(s):  
Yuri Geraldo ◽  
Livia Leandro ◽  
Ana Raquel Silva ◽  
Fábia Campina ◽  
Ana Carolina Araújo ◽  
...  

The objective of this study was to evaluate the antibacterial and modulatory activities of ethanolic extract of Calotropis procera (Aiton) W.T. Aiton against resistant species. By microdilution method, the minimum inhibitory concentration (MIC) of the extract and modulation of the subinhibitory concentration MIC/8 to norfloxacine, gentamicin and imipenem against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. There was obtained 512 μg/mL to Pseudomonas aeruginosa. To Staphylococcus aureus, modulation showed synergism to norfloxacin and gentamicin, with imipenem against Pseudomonas aeruginosa and gentamicin against Escherichia coli. Based on these results, more studies are needed to test the antibacterial activity of the extract. El objetivo de este estudio fue evaluar la actividad antibacteriana y moduladora del extracto etanólico de Calotropis procera (Aiton) W.T. Aiton contra cepas multirresistentes de bacterias. Por el método de microdilución, fueron definidas la concentración inhibidora mínima (MIC) del extracto y la modulación con la concentración inhibidora CIM / 8 del extracto con norfloxacina, gentamicina e imipenem contra Staphylococcus aureus, Escherichia coli y Pseudomonas aeruginosa. Se obtuvo 512 μg/mL para Pseudomonas aeruginosa. Se descubrió sinergismo en el caso de Staphylococcus aureus, en la modulación con norfloxacina y gentamicina, mientras que con imipenem frente a Pseudomonas aeruginosa y con gentamicina para Escherichia coli. Con base en estos resultados, se necesitan más estudios para probar la actividad antibacteriana del extracto.

2018 ◽  
Vol 88 (5-6) ◽  
pp. 244-250 ◽  
Author(s):  
Jacqueline C. Andrade ◽  
Maria Flaviana B. Morais Braga ◽  
Gláucia Morgana M. Guedes ◽  
Saulo R. Tintino ◽  
Maria A. Freitas ◽  
...  

Abstract. Background: This is the first report demonstrating the antibiotic-modifying activity of cholecalciferol. Aim: In this study, cholecalciferol was evaluated against multiresistant strains of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Methods: The antibacterial and modulatory effects of cholecalciferol, ergosterol, and cholesterol (8–512 μg/mL) were evaluated by microdilution assay against multiresistant bacterial strains. Results: Cholecalciferol, when combined with aminoglycosides, was more effective against P. aeruginosa, reducing the concentration of amikacin and gentamicin necessary to inhibit bacterial growth from 156.25 to 39.06 μg/mL and from 39.06 to 9.76 μg/mL, respectively. It is possible that cholecalciferol, due to its lipid-soluble nature, had a lipophilic interaction with the cell membrane, enhancing antibiotic uptake. Cholesterol and ergosterol were used to see if the mechanism of action of cholecalciferol was similar to that of these lipid compounds. Ergosterol and cholesterol increased aminoglycoside activity, where the effect was greater with higher subinhibitory concentration of sterol. Conclusions: There is no reported study on the use of cholesterol and ergosterol as modulators of antibiotics or any other drug, making this the first study in this area highlighting the interaction between cholesterol, ergosterol, and cholecalciferol with regard to modifying aminoglycoside activity.


2018 ◽  
Vol 21 (0) ◽  
Author(s):  
Flávia Cíntia de Oliveira ◽  
Tamara Rezende Marques ◽  
Gustavo Henrique Andrade Machado ◽  
Thaís Cristina Lima de Carvalho ◽  
Aline Aparecida Caetano ◽  
...  

Abstract The phenolic compounds from various extracts of jabuticaba skin powder (JSP) were characterized in this study, and the antibacterial activity assessed. The phenolic compounds were extracted from the JSP using four methods: a) acetone extraction - 1 g JSP: 10 mL 70% acetone, resting for 2 hours; b) aqueous extract - 1 g JSP: 15 mL water, under agitation; c) ethanolic extract - 1 g JSP: 15 mL acidified ethanol, under agitation; and d) methanolic extract - 1 g JSP: 50 mL 50% methanol, under reflux. The antibacterial activity was evaluated by the agar diffusion assay, using Escherichia coli ATCC 11229, Salmonella choleraesuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19117. The ethanolic and methanolic extracts showed the highest levels of phenolic compounds, especially of cyanidin chloride, catechin and epicatechin. The extracts did not inhibit the growth of Escherichia coli and Salmonella choleraesuis, but inhibited 30% of the growth of Pseudomonas aeruginosa with an extract concentration of 250 µg mL-1. Against Staphylococcus aureus and Listeria monocytogenes the highest inhibitory effect observed was 41.8% for the ethanolic extract, followed by 36% inhibition by the methanolic extract, thus revealing the potential of these extracts as possible alternatives for use in the food and/or pharmaceutical industries.


2021 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Antonio Carlos Pereira de Menezes Filho ◽  
Matheus Vinícius Abadia Ventura ◽  
Carlos Frederico de Souza Castro

Tibouchina granulosa is a species that blooms annually in several regions of Brazil. This species is still little explored in terms of phytocompounds in all organs of this plant, especially the floral organ. Flowers of T. granulosa were collected in the municipality of Rio Verde, Goiás, Brazil, in 2021. The hydroethanolic floral extract was prepared by maceration and qualitative phytochemical (colorimetric reactions and salt formation) and antibacterial analyzes performed and the results expressed in millimeters of inhibition at different concentrations in mg mL-1. Several phytochemical classes were observed with positive results, especially for alkaloids, phenolics, oxylates, saponins, carbohydrates and tannins. As for the bacterial assay, potential antibacterial activity was observed for all bacterial strains tested, except for Salmonella serovar Thyphymurium and serovar Enteritidis. Expressive inhibitions were observed for Enterococcus faecalis > Pseudomonas aeruginosa > Staphylococcus aureus and Escherichia coli at the highest concentrations between 100-50 mg mL-1. The floral extract of Tibouchina granulosa showed phytotherapeutic potential with the presence of several phytochemical groups and expressive antibacterial activity.


2018 ◽  
Vol 13 (4) ◽  
pp. 1934578X1801300
Author(s):  
Daniyar Sadyrbekov ◽  
Timur Saliev ◽  
Yuri Gatilov ◽  
Ivan Kulakov ◽  
Roza Seidakhmetova ◽  
...  

A cyclopropane derivative of limonene, (1 S, 4 S, 6 R)-7,7-dichloro-4-[(1 S)-2,2-dichloro-1-methylcyclopropyl]-1-methylbicyclo [4.1.0] heptane (compound 2), was synthesized and its structure was determined by NMR and X-ray crystallographic methods. In addition, an antimicrobial activity of the compound against Gram-positive ( Staphylococcus aureus, Bacillus subtilis) and Gram-negative ( Escherichia coli, Pseudomonas aeruginosa) bacterial strains was also scrutinized.


DICP ◽  
1989 ◽  
Vol 23 (6) ◽  
pp. 456-460
Author(s):  
Michael N. Dudley ◽  
Hilary D. Mandler ◽  
Kenneth H. Mayer ◽  
Stephen H. Zinner

Serum inhibitory and bactericidal titers were measured in nine healthy volunteers following single iv doses of ciprofloxacin 100, 150, and 200 mg. The median peak serum bactericidal titer (5 minutes following completion of a 30-minute infusion) against two highly susceptible strains of Escherichia coli ranged between 1:64 and 1:1024 and titers exceeded 1:8 for six hours for all dose levels. The bactericidal titers against two strains of Pseudomonas aeruginosa and a methicillin-resistant strain of Staphylococcus aureus were considerably lower, the median peak being 1:2 at all dose levels. Measured inhibitory and bactericidal titers at five minutes and one hour postinfusion were significantly greater than those predicted (measured serum ciprofloxacin concentration to minimum inhibitory concentration [MIC] or minimum bactericidal concentration [MBC]) for only one strain of E. coli. Intravenous doses of ciprofloxacin 100–200 mg produce high and sustained serum bactericidal titers against highly susceptible bacteria; considerably lower levels of activity are seen against bacteria having higher MICs and MBCs but still considered susceptible to the drug.


Author(s):  
Hamdollah Moshtaghi ◽  
Azadeh Rashidimehr ◽  
Behzad Shareghi

Background: To prevent or inhibit the growth of pathogenic microorganisms and food spoilage factors, many studies have been done by using natural preservatives. The aim of study was to investigate the effect of different concentrations of lysozyme and Nisin on the growth rate and also to determine the minimum inhibitory concentration (MIC) and minimum bactericidal cocentratiin (MBC) of these combinations on the bacteria of Escherichia coli, Staphylococcus aureus, Salmonella typhimorium and Listeria monocytogenes. Methods: In this study, various concentrations of lysozyme and Nisin were set in form of alone concentration and in combination concentrations (0, 19.53, 39.06, 78.13, 156.25, 312.5, 625, 1250, 2500, 5000) in vitro conditions and 6 pH 5.5, 6, 6.5, 7, 7.5, and 8. Microdilution method at 24°C was done and the combined effect on bacteria growth was read by using ELISA reader. Results: The results showed that lysozyme was less effective on Escherichia coli and Nisin was less effective on Listeria monocytogenes. Moreover, combining lysozyme and Nisin at low pH decreased the MIC. Conclusions: The results of the study showed that the effect of combining lysozyme and Nisin on Staphylococcus aureus is above all other bacteria and at low pH reduces the MIC.


2019 ◽  
Vol 10 (2) ◽  
pp. 1190-1195
Author(s):  
Neeraja Rani Guruvu ◽  
Bandaru Narasinga Rao ◽  
Vijayaraghavan R ◽  
Sukumar E ◽  
Senthilkumar Sivanesan

Honey is used as food and home remedy in of India and other countries. Scientific studies have been carried out to support these properties of honey in this investigation, incision wounds of rats that were infected with three bacterial strains viz. Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, have been treated with honey and evaluated for its effect on days 1, 3, 6, 9 and 12 post-operatively with the help of smears and biopsies collected from lesions. Cytological and histopathological investigations of infected wounds conformed significant healing property of honey in and reduction in size.


2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Gino Nemesio Cepeda ◽  
Meike Meilan Lisangan ◽  
Isak Silamba ◽  
Nitia Nilawati ◽  
Eka Syartika

ABSTRACT  Akway (Drimys piperita) is a woody, evergreen and aromatic plant that belongs to family winteraceae. This plant is used by Sougb tribe lived in Sururey village, District of Anggi, to enhance the vitality of body. The objectives of the research were to determine antimicrobial stability of akway bark extracts influenced by heating time of 100OC, levels of acidity (pH) and salt contents.. Antimicrobial assays were done by using agar well diffusion method against four species of bacteria, i.e.  Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. The results showed that ethanolic extracts of akway bark only inhibited growth of B. cereus and S. aureus with minimum inhibitory concentration 0,99% and 0,89% . The levels of concentration and acidity of ethanol extracts  influenced the antimicrobial capacity of extracts.. Whereas heating time on 100OC during 25 minutes and salt contents  up to 5% of extract solution did not influence the antimicrobial stability of  akway bark extracts. Key words : akway, extracts, antimicrobe, pH, Heating, salt ABSTRAK Akway (Drimys piperita) adalah tumbuhan berkayu, aromatik dan hijau sepanjang tahun dan tergolong dalam suku winteraceae. Tumbuhan ini digunakan oleh Suku Sougb yang bermukim di desa Sururey Distrik Anggi, untuk mengobati malaria dan meningkatkan vitalitas tubuh. Tujuan dari penelitian ini adalah untuk menentukan stabilitas antimikroba ekstrak kulit kayu akway pada waktu pemanasan ekstrak pada 100OC, tingkat keasaman (pH) dan kandungan garam. Pengujian antimikroba dilakukan dengan menggunakan metode difusi agar terhadap empat spesies bakteri yaitu Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. Hasil menunjukkan bahwa ekstrak etanol kulit kayu akway hanya dapat menghambat bakteri Bacillus cereus dan Staphylococcus aureus dengan konsentrasi hambat minimum masing-masing adalah 0,99% dan 0,89%. Tingkat konsentrasi dan keasaman (pH) mempengaruhi kapasitas antimikroba ekstrak etanol kulit kayu akway. Sedangkan perlakuan pemanasan pada suhu 100OC dengan lama pemanasan sampai dengan 25 menit dan penambahan garam NaCl sampai konsentrasi 5%  tidak berpengaruh pada stabilitas antimikroba ekstrak etanol kulit kayu akway.  


2014 ◽  
Vol 9 (5) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Maria T. A. Oliveira ◽  
Alexandre M R. Teixeira ◽  
Henrique D. M. Coutinho ◽  
Irwin R. A. Menezes ◽  
Diniz M. Sena ◽  
...  

The n-hexane extract of the stem bark of Croton anisodontus yielded 2-hydroxy-3,4,6-trimethoxyacetophenone, a well-known substance, but isolated from this species for the first time. The antimicrobial and modulatory activities of the compound towards Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, C krusei and C tropicalis strains were assessed. Antibiotics such as amikacin, gentamicin and neomycin were used in a subinhibitory concentration. Significant activity was observed towards P. aeruginosa and S. aureus 358, with p < 0.001 in association with amikacin. The present results place C anisodontus as an alternative source of 2-hydroxy-3,4,6-trimethoxyacetophenone with antibacterial potential.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Fernando G. Figueredo ◽  
Emerson O. Ferreira ◽  
Bruno F. F. Lucena ◽  
Cícero M. G. Torres ◽  
Daniel L. Lucetti ◽  
...  

The aim of this study was to verify the possible interactions between ethanol extracts ofAmburana cearensisA. C. Smith andAnadenanthera macrocarpa(Benth.) Brenan, combined with six antimicrobial drugs against multiresistant strains ofStaphylococcus aureusandEscherichia coliisolated from humans. The antibacterial activity of the extracts was determined using the minimum inhibitory concentration (MIC). The microdilution assay was performed to verify the interactions between the natural products and the antibiotics using a subinhibitory concentration. The activity of amikacin associated with the extract ofAnadenanthera macrocarpaagainst EC 27 was enhanced, demonstrating an MIC reduction from 128 to 4 μg/mL. Among theβ-lactams, no potentiation on its activity was observed, with exception to the antagonism of the natural products with ampicillin againstS. aureus358.


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