Protection against Escherichia coli infection by antibody to the Staphylococcus aureus poly-N-acetylglucosamine surface polysaccharide

Poly-N-acetylglucosamine (PNAG) is a surface polysaccharide produced by Staphylococcus aureus and Staphyloccus epidermidis and is an effective target for opsonic and protective Ab for these two organisms. Recently, it has been found that Escherichia coli produces an exo-polysaccharide, designated polyglucosamine, that is biochemically indistinguishable from PNAG. We analyzed 30 E. coli strains isolated from urinary tract and neonatal bloodstream infections for the pga locus, PNAG antigen production, and susceptibility to opsonic killing and protection from lethal infection by Ab to PNAG. Twenty-six of 30 strains carried the pga locus, 25 of 30 expressed immunologically detectable PNAG, and 21 of 30 could be killed by rabbit IgG specific for the deacetylated form of the staphylococcal PNAG. Ab to staphylococcal PNAG protected mice against lethality from five different E. coli strains expressing PNAG. PNAG expression by both Gram-negative and Gram-positive organisms could make this antigen a conserved vaccine target for multiple pathogenic species of bacteria.

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Synthesis of Chalcones and Nucleosides Incorporating [1, 3, 4]Oxadiazolenone Core and Evaluation of their Antifungal and Antibacterial Activities

Current Bioactive Compounds ◽

10.2174/1573407214666180911130110 ◽

2020 ◽

Vol 15 (6) ◽

pp. 665-679

Author(s):

Alok K. Srivastava ◽

Lokesh K. Pandey

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Bacillus Subtilis ◽

Antifungal Activity ◽

Aspergillus Niger ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

Good Antibacterial Activity

Background: [1, 3, 4]oxadiazolenone core containing chalcones and nucleosides were synthesized by Claisen-Schmidt condensation of a variety of benzaldehyde derivatives, obtained from oxidation of substituted 5-(3/6 substituted-4-Methylphenyl)-1, 3, 4-oxadiazole-2(3H)-one and various substituted acetophenone. The resultant chalcones were coupled with penta-O-acetylglucopyranose followed by deacetylation to get [1, 3, 4] oxadiazolenone core containing chalcones and nucleosides. Various analytical techniques viz IR, NMR, LC-MS and elemental analysis were used to confirm the structure of the synthesised compounds.The compounds were targeted against Bacillus subtilis, Staphylococcus aureus and Escherichia coli for antibacterial activity and Aspergillus flavus, Aspergillus niger and Fusarium oxysporum for antifungal activity. Methods: A mixture of Acid hydrazides (3.0 mmol) and N, Nʹ- carbonyl diimidazole (3.3 mmol) in 15 mL of dioxane was refluxed to afford substituted [1, 3, 4]-oxadiazole-2(3H)-one. The resulted [1, 3, 4]- oxadiazole-2(3H)-one (1.42 mmol) was oxidized with Chromyl chloride (1.5 mL) in 20 mL of carbon tetra chloride and condensed with acetophenones (1.42 mmol) to get chalcones 4. The equimolar ratio of obtained chalcones 4 and β -D-1,2,3,4,6- penta-O-acetylglucopyranose in presence of iodine was refluxed to get nucleosides 5. The [1, 3, 4] oxadiazolenone core containing chalcones 4 and nucleosides 5 were tested to determined minimum inhibitory concentration (MIC) value with the experimental procedure of Benson using disc-diffusion method. All compounds were tested at concentration of 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.62 mg/mL, 0.31 mg/mL and 0.15 mg/mL for antifungal activity against three strains of pathogenic fungi Aspergillus flavus (A. flavus), Aspergillus niger (A. niger) and Fusarium oxysporum (F. oxysporum) and for antibacterial activity against Gram-negative bacterium: Escherichia coli (E. coli), and two Gram-positive bacteria: Staphylococcus aureus (S. aureus) and Bacillus subtilis(B. subtilis). Result: The chalcones 4 and nucleosides 5 were screened for antibacterial activity against E. coli, S. aureus and B. subtilis whereas antifungal activity against A. flavus, A. niger and F. oxysporum. Compounds 4a-t showed good antibacterial activity whereas compounds 5a-t containing glucose moiety showed better activity against fungi. The glucose moiety of compounds 5 helps to enter into the cell wall of fungi and control the cell growth. Conclusion: Chalcones 4 and nucleosides 5 incorporating [1, 3, 4] oxadiazolenone core were synthesized and characterized by various spectral techniques and elemental analysis. These compounds were evaluated for their antifungal activity against three fungi; viz. A. flavus, A. niger and F. oxysporum. In addition to this, synthesized compounds were evaluated for their antibacterial activity against gram negative bacteria E. Coli and gram positive bacteria S. aureus, B. subtilis. Compounds 4a-t showed good antibacterial activity whereas 5a-t showed better activity against fungi.

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SEPSIS MARKERS AND SENSITIVITY OF STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI ISOLATES IN A GENERAL HOSPITAL SETTING

Vestnik ◽

10.53065/kaznmu.2021.86.69.013 ◽

2021 ◽

pp. 68-74

Author(s):

М.Е. Рамазанов ◽

В.Н. Сон ◽

М.Р. Рысулы ◽

С.Т. Турсуналиев ◽

Е.Б. Еспенбетов

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Hospital Setting ◽

Bloodstream Infections ◽

High Sensitivity ◽

Clinical Isolates ◽

Empiric Antibiotic Therapy ◽

E Coli ◽

Number Of Patients ◽

Empiric Antibiotic

Представлены результаты проспективного обследования 80 больных ГКБ №7 с бактериемией с октября 2019 года по февраль 2021 года из различных отделений госпиталя. Производилась оценки показателей маркеров сепсиса - пресепсина, прокальцитонина и С-реактивного белка (СРБ) в крови больных в динамике эмпирической терапии антимикробными препаратами (АМП). Наибольшее число больных с выявленной бактериемией находилось в отделении ОАРИТ - 39 пациентов, у 25 из них был диагностирован сепсис по шкале СЕПСИС III, вызванный известными патогенами Staphylococcus aureus (46,6%) и Escherichia coli (36,6%). Для эмпирического лечения применялись различные антибиотики: ампенициллин, амикацин, меропенем, цефотаксим, метрид, ципрофлоксацин, ципрокс, цефлокс, цефазолин, цефтриаксон, левофлоксацин. Уровни прокальцитонина составляют для больных с клиническими изолятами E. coli 20,8±3,1нг/мл, а для изолятов St. aureus 15,7±1,8 нг/мл. После терапии АМП наблюдается значительное снижение показателей до 1,43±0,6 и 2,3±0,9 нг/мл., что позволяет признать эффективность эмпирической антибиотикотерапии при инфекциях кровотока. Высокая чувствительность клинических изолятов Escherichia coli отмечена к препаратам группы карбапенемов - имипенему и меропенему (90,9%), низкая к эртапенему (72,7%). 100% чувствительность все изоляты показали по отношению к АМП из группы глицилциклинов - тигециклину, который структурно сходен с тетрациклинами. Высокой резистеностью клинические изоляты Staphylococcus aureus обладают к пенициллину (92,9%), липопептиду природного происхождения даптомицину (85,8%) и препарату из группы линкозамидов - клиндамицину (64,3%). The results of a prospective examination of 80 patients with bacteremia from October 2019 to February 2021 from various departments of the hospital are presented. The largest number of patients with detected bacteremia were in the OARIT department - 39 patients, 25 of them were diagnosed with sepsis according to the SEPSIS III scale, caused by known pathogens Staphylococcus aureus (46.6%) and Escherichia coli (36.6%). For empirical treatment, various antibiotics were used: ampenicillin, amikacin, meropenem, cefotaxime, metrid, ciprofloxacin, ciprox, ceflox, cefazolin, ceftriaxone, levofloxacin. Procalcitonin levels for patients with clinical E. coli isolates are 20.8 ± 3.1 ng / ml, and for St. aureus 15.7 ± 1.8 ng / ml. After AMP therapy, there is a significant decrease in indicators to 1.43 ± 0.6 and 2.3 ± 0.9 ng / ml, which makes it possible to recognize the effectiveness of empiric antibiotic therapy for bloodstream infections. High sensitivity of clinical isolates of Escherichia coli was noted to drugs of the carbapenem group - imipenem and meropenem (90.9%), low to ertapenem (72.7%). All isolates showed 100% sensitivity to AMPs from the glycylcycline group - tigecycline, which is structurally similar to tetracyclines. Clinical isolates of Staphylococcus aureus are highly resistant to penicillin (92.9%), natural lipopeptide daptomycin (85.8%), and a drug from the lincosamide group - clindamycin (64.3%).

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Clinical Blood Isolates from Hemodialysis Patients: Distribution of Organisms and Antimicrobial Resistance, 2007–2014

The Canadian Journal of Hospital Pharmacy ◽

10.4212/cjhp.v73i4.3025 ◽

2020 ◽

Vol 73 (4) ◽

Author(s):

Courtney K Lawrence ◽

Chris Sathianathan ◽

Mauro Verrelli ◽

Philippe Lagacé-Wiens ◽

Robert Ariano ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Bloodstream Infections ◽

Hemodialysis Patients ◽

Gram Negative Bacteria ◽

Blood Isolate ◽

Gram Negative ◽

Essential Components ◽

Over Time

Background: Given the morbidity and mortality associated with bloodstream infections in hemodialysis patients, understanding the microbiology is essential to optimizing treatment in this high-risk population.Objectives: To conduct a retrospective surveillance study of clinical blood isolates from adult hemodialysis patients, and to predict the microbiological coverage of empiric therapies for bloodstream infections in this population.Methods: Clinical blood isolate data were collected from the 4 main outpatient hemodialysis units in Winnipeg, Manitoba, from 2007 to 2014. The distribution of organisms and antimicrobial susceptibilities were characterized. When appropriate, changes over time were tested using time series analysis. Study data were used to predict and compare the microbiological coverage of various empiric therapies for bloodstream infections in hemodialysis patients.Results: The estimated annual number of patients receiving chronic hemodialysis increased steadily over the study period (p < 0.001), whereas the number of blood isolates increased initially, then decreased significantly, from 180 in 2011 to 93 in 2014 (p = 0.04). Gram-positive bacteria represented 72.6% (743/1024) of isolates, including Staphylococcus aureus (36.9%, 378/1024) and coagulase-negative staphylococci (23.1%, 237/1024). Only 26.1% (267/1024) of the isolates were gram-negative bacteria, the majority Enterobacteriaceae. The overall rate of methicillin resistance in S. aureus was 17.5%, and although annual rates were variable, there was a significant increase over time (p = 0.04). Antibiotic resistance in gram-negative bacteria was relatively low, except in Escherichia coli, where 13.5% and 16.2% of isolates were resistant to ceftriaxone and ciprofloxacin, respectively. Empiric therapy with vancomycin plus an agent for gram-negative coverage was predicted to cover 98.8% to 99.7% of blood isolates from hemodialysis patients, whereas cefazolin plus an agent for gram-negative coverage would cover only 67.5% to 68.4%.Conclusions: In an era of increasing antimicrobial resistance, data such as these and ongoing surveillance are essential components of antimicrobial stewardship in the hemodialysis population.Keywords: hemodialysis, microbiology, surveillance, resistance, antimicrobial stewardshipRÉSUMÉ Contexte : Étant donné la morbidité et la mortalité associées aux infections du sang parmi les patients en hémodialyse, la compréhension de la microbiologie est essentielle à l’optimisation du traitement de cette population exposée à un risque élevé.Objectifs : Mener une étude de surveillance rétrospective des isolats de sang cliniques des patients adultes en hémodialyse et prédire la couverture microbiologique des thérapies empiriques contre les infections du sang dans cette population.Méthodes : Les données relatives aux isolats de sang cliniques ont été recueillies dans les quatre unités ambulatoires principales d’hémodialyse à Winnipeg (Manitoba), entre 2007 et 2014. La caractérisation a porté sur la distribution des organismes et les susceptibilités aux antimicrobiens. L’évolution dans le temps a été testée au besoin à l’aide d’une analyse chronologique. Les données de l’étude ont permis de prédire et de comparer la couverture microbiologique de diverses thérapies empiriques contre les infections du sang pour les patients en hémodialyse.Résultats : On estime que le nombre annuel de patients recevant une hémodialyse chronique a augmenté régulièrement au cours de la période de l’étude (p < 0,001); le nombre d’isolats de sang a tout d’abord augmenté, puis il a grandement diminué : de 180 en 2011, il est passé à 93 en 2014 (p = 0,04). Les bactéries à Gram positif représentaient 72,6 % (743/1024) des isolats, y compris les Staphylococcus aureus (36,9 %, 378/1024) et les staphylocoques à coagulase négative (23,1 %, 237/1024). Seulement 26,1 % (267/1024) des isolats étaient des bactéries à Gram négatif, la majorité desquelles étant des Enterobacteriaceae. Le taux général de résistance à la méticilline de S. aureus était de 17,5 %, et bien que les taux annuels étaient variables, une augmentation importante a été observée avec le temps (p = 0,04). La résistance aux antibiotiques des bactéries à Gram négatif était relativement faible, sauf Escherichia coli, où respectivement 13,5 % et 16,2 % des isolats étaient résistants à la ceftriaxone et à la ciprofloxacine. On prévoyait que la thérapie empirique à la vancomycine associée à un agent pour la couverture à Gram positif couvrirait de 98,8 % à 99,7 % des isolats de sang des patients en hémodialyse, tandis que la céfazoline associée à un agent de la couverture à Gram négatif ne couvrirait que 67,5 % à 68,4 %.Conclusions : À une époque qui se caractérise par une augmentation de la résistance aux antimicrobiens, des données comme celles-ci et celles portant sur la surveillance continue sont des composantes essentielles de la bonne gestion de l’utilisation des antimicrobiens pour les patients adultes en hémodialyse.Mots-clés : hémodialyse, microbiologie, surveillance, résistance, gestion de l’utilisation des antimicrobiens

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Oxidative Stress and Antimicrobial Activity of Chromium(III) and Ruthenium(II) Complexes onStaphylococcus aureusandEscherichia coli

BioMed Research International ◽

10.1155/2013/906912 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 13

Author(s):

Paulina L. Páez ◽

Claudia M. Bazán ◽

María E. Bongiovanni ◽

Judith Toneatto ◽

Inés Albesa ◽

...

Keyword(s):

Oxidative Stress ◽

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Antibacterial Agents ◽

Antibacterial Activities ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

Diimine Ligands

The prevalence of antibiotic resistance has resulted in the need for new approaches to be developed to combat previously easily treatable infections. The main aim of this work was to establish the potential of the syntheticα-diimine chromium(III) and ruthenium(II) complexes (where theα-diimine ligands are bpy = 2,2-bipyridine, phen = 1,10-phenanthroline, and dppz = dipyrido[3,2-a:2′,3′-c]-phenazine) like [Cr(phen)3]3+, [Cr(phen)2(dppz)]3+, [Ru(phen)3]2+, and [Ru(bpy)3]2+as antibacterial agents by generating oxidative stress. The [Cr(phen)3]3+and [Cr(phen)2(dppz)]3+complexes showed activity against Gram positive and Gram negative bacteria with minimum inhibitory concentrations (MICs) ranging from 0.125 μg/mL to 1 μg/mL, while [Ru(phen)3]2+and [Ru(bpy)3]2+do not exhibit antimicrobial activity against the two bacterial genera studied at the concentration range used. When ciprofloxacin was combined with [Cr(phen)3]3+for the inhibition ofStaphylococcus aureusandEscherichia coli, an important synergistic effect was observed, FIC 0.066 forS. aureusand FIC 0.064 forE. coli. The work described here shows that chromium(III) complexes are bactericidal forS. aureusandE. coli. Our results indicate thatα-diimine chromium(III) complexes may be interesting to open new paths for metallodrug chemotherapy against different bacterial genera since some of these complexes have been found to exhibit remarkable antibacterial activities.

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Antimicrobial Resistance in Pathogens Isolated from Blood Cultures: A Two-Year Multicenter Hospital Surveillance Study in Italy

Antibiotics ◽

10.3390/antibiotics10010010 ◽

2020 ◽

Vol 10 (1) ◽

pp. 10

Author(s):

Francesca Licata ◽

Angela Quirino ◽

Davide Pepe ◽

Giovanni Matera ◽

Aida Bianco ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Bloodstream Infections ◽

Electronic Record ◽

Coagulase Negative Staphylococcus ◽

Surveillance Systems ◽

Gram Negative ◽

Medicine Today ◽

High Level

Background: Antimicrobial resistance (AMR) is one of the most concerning issues in medicine today. The objectives of this study were to investigate the AMR distribution of the blood-borne pathogens isolated over a two-year period in an Italian region. Methods: A retrospective electronic record review of laboratory-confirmed bloodstream infections (BSIs) was done, and data from three major diagnostic laboratories were used. Twelve invasive clinically important bacteria species were included in the sample. Results: During the study period, 1228 positive BSIs were collected. The most common pathogens were Coagulase-negative Staphylococcus (CoNS) (29.7%), Staphylococcus aureus (19.1%) and Escherichia coli (15.9%). With regard to the AMR pattern, 31.7% of CoNS and 28.1% of Staphylococcus aureus were oxacillin-resistant, and almost half of the Enterococci showed resistance to high-level gentamicin. Among Gram-negative species, 11.7% of Escherichia coli and 39.5% of Klebsiella pneumoniae were carbapenem-resistant. Among the non-fermentative Gram-negative bacteria, the most frequently combined AMR pattern was aminoglycosides and fluoroquinolones (48.4% in A. baumannii and 14.6% in P. aeruginosa). Conclusion: The results display an alarming prevalence of AMR among hospital isolated pathogens, consistently higher than the European average. Information from surveillance systems to better characterize the trend in the incidence of AMR at local and national levels is needed.

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Evaluation of Antibacterial Activity of Three Quaternary Ammonium Disinfectants on Different Germs Isolated from the Hospital Environment

BioMed Research International ◽

10.1155/2020/6509740 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Amal Ramzi ◽

Bouchra Oumokhtar ◽

Yassine Ez zoubi ◽

Touria Filali Mouatassem ◽

Moussa Benboubker ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Quaternary Ammonium ◽

Inhibitory Concentration ◽

Hospital Environment ◽

Gram Positive ◽

Gram Negative ◽

E Coli

Background. The microbiological risk of the hospital environment, including inert surfaces, medical devices, and equipment, represents a real problem. Objective. This study is aimed at demonstrating and assessing the antibacterial activity of three synthetic disinfectants classified as quaternary ammoniums on different bacterial strains (Gram-negative and Gram-positive like Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus) isolated from the hospital environment. The reference strains included Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Pseudomonas aeruginosa ATCC 27853 used as negative control strains. Method. Three quaternary ammonium disinfectants were tested: DDN9® (0.5%) which contains didecylmethylpolyoxyethylammonium propionate as an active substance, spray (0.4%) containing quaternary ammonium compounds, and Phagosurf ND® (0.4%) with didecyldimethylammonium chloride. Their effect was evaluated using the disk diffusion technique and the broth dilution methods, allowing the Minimum Inhibitory Concentration (MIC) and then the Minimum Bactericidal Concentration (MBC). Result. Only the growth of Gram-positive bacteria and some strains of Gram-negative bacteria were inhibited by the three synthetic disinfectants. NDD9® demonstrated an antibacterial effect only against the Gram-positive strains (S. aureus and S. aureus ATCC 29213) with a MIC of 0.25 mg/ml. The disinfectant spray showed effect against all four strains including E. coli (9), S. aureus, E. coli ATCC 25922, and P. aeruginosa ATCC 27853 with an inhibitory concentration of 4 mg/ml, while the growth of S. aureus ATCC 29213 was inhibited at 2 mg/ml. The third disinfectant, Phagosurf ND®, inhibited only the growth of S. aureus ATCC 29213 at a MIC of 4 mg/ml. Conclusion. This study is the first here in Morocco to evaluate the bacterial activity of products intended for the control of the healthcare environment. The results obtained on the three disinfectants tested reveal an ineffectiveness against some isolated strains from the hospital environment.

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AKTIVITAS ANTIBAKTERI INFUSA DAUN MUDA MANGROVE Sonneratia alba KERING

MEDIA TEKNOLOGI HASIL PERIKANAN ◽

10.35800/mthp.7.2.2019.23613 ◽

2019 ◽

Vol 7 (2) ◽

pp. 52

Author(s):

Yayu Mukhmin Ibrahim ◽

Verly Dotulong ◽

Djuhria Wonggo ◽

Helen Jenny Lohoo ◽

Roike Iwan Montolalu ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Extraction Time ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Sample Concentration ◽

Sonneratia Alba ◽

Escherichia Coli Bacteria

Sonneratia alba mangroves are known to have bioactive compounds such as antibacterial. The purpose of this study was to determine the antibacterial activity of extract of S. alba dried mangrove leaves on Gram positive Staphylococcus aureus and Gram negative Escherichia coli bacteria. Extraction method by infusion, extraction time is 40 and 50 minutes. The extract obtained was then evaporated by the solvent above the water bath then the extracts were made concentrations of 5 and 10%. Antibacterial testing uses the modified Kirby-Bauer method. The highest yield is found in the treatment of 50 minutes infusion extraction time which is 15.6 ± 0.2%. The highest antibacterial activity against S. aureus was found in the treatment of 50 minutes extraction time both for 5% sample concentration of 7.0 mm (medium category) and at a sample concentration of 10% at 8.0 mm (medium category). While the highest antibacterial activity against E. coli bacteria was found in the treatment of 50 minutes extraction time both at 5% sample concentration of 8.0 (medium category) mm and at 10% sample concentration of 8.3 mm (medium category). From these results it can be seen that the S. alba extract of young mangrove leaf infusion has a broad spectrum antibacterial activity because it can inhibit both Gram positive S. aureus and Gram negative E. coli bacteria.Keyword: Mangrove, Sonneratia alba, infusion, rendemen, antibacterial. Mangrove Sonneratia alba diketahui memiliki senyawa bioaktif seperti antibakteri. Tujuan dari penelitian ini untuk mengetahui aktivitas antibakteri ekstrak Infusa daun muda mangrove S. alba kering terhadap bakteri Grampositif Staphylococcus aureus dan bakteri Gram negatif Escherichia coli. Metode ekstraksi dengan cara infusa, lama waktu ekstraksi yaitu40 dan 50 menit. Ekstrak yang didapatkan kemudian dievaporasi pelarutnya diatas penangas air kemudian hasil ekstrak dibuat konsentrasi 5 dan 10%. Pengujian antibakteri menggunakan metode Kirby-Bauer yang dimodifikasi. Rendemen tertinggi terdapat pada perlakuan lama ekstraksi infusa 50 menit yaitu sebesar 15,6±0,2 %. Aktivitas antibakteri tertinggi terhadap bakteri S. aureus terdapat pada perlakuan lama ekstraksi 50 menit baik untuk konsentrasi sampel 5% sebesar 7,0 mm (kategori sedang) dan pada konsentrasi sampel 10% sebesar 8,0 mm (kategori sedang). Sedangkan aktivitas antibakteri tertinggi terhadap bakteri E. coli terdapat pada perlakuan lama ekstraksi 50 menit baik pada konsentrasi sampel 5% sebesar 8,0 mm (kategori sedang) dan pada konsentrasi sampel 10% sebesar 8,3 mm (kategori sedang). Dari hasil ini dapat dilihat bahwa ekstrak infusa daun muda mangrove S. alba mempunyai aktivitas antibakteri dengan spektrum yang luas karena dapat menghambat baik bakteri Gram positif S. aureus maupun Gram negatif E. coli.Kata kunci: Mangrove, Sonneratia alba, infusa, rendemen, antibakteri.

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Surveillance of antimicrobial resistance of invasive pathogens: the Estonian experience

Eurosurveillance ◽

10.2807/esm.11.02.00601-en ◽

2006 ◽

Vol 11 (2) ◽

pp. 9-10 ◽

Cited By ~ 2

Author(s):

K Loivukene ◽

K Kermes ◽

E Sepp ◽

V Adamson ◽

P Mitt ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Surveillance System ◽

Gram Negative ◽

E Coli ◽

Invasive Pathogens ◽

Susceptibility Data ◽

Antimicrobial Resistance Surveillance ◽

Klebsiella Spp

The aim of the present study was to evaluate the needs for surveillance of invasive Gram-negative pathogens in Estonia. The antimicrobial susceptibility data of invasive isolates of Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella spp, Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae and enterococci were collected in accordance with EARSS (European Antimicrobial Resistance Surveillance System) protocols. Despite the higher rate of Gram positive pathogens, their resistance to antimicrobials was low in contrast to the elevated resistance established for Gram negative pathogens. The higher resistance to antimicrobials was particularly associated with A. baumannii and P. aeruginosa. Also, the proportion of extended spectrum betalactamase (ESBL)-producing strains was 23% among Klebsiella spp. and 3.6% among E. coli. The inclusion of invasive Gram negative pathogens in antimicrobial resistance surveillance provides useful information concerning local pathogen susceptibility, as well as for the empirical treatment of suspected infections.

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Antibacterial Activity of Borassus flabellifer Vinegar-Graphene Quantum Dots Against Gram-Positive and Gram-Negative Bacteria

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23376 ◽

2021 ◽

Vol 33 (11) ◽

pp. 2662-2666

Author(s):

Amnuay Noypha ◽

Paweena Porrawatkul ◽

Nongyao Teppaya ◽

Parintip Rattanaburi ◽

Saksit Chanthai ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Quantum Dots ◽

Antibacterial Activity ◽

Graphene Quantum Dots ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

E Coli

Borassus flabellifer vinegar–graphene quantum dots (BFV-GQDs) were successfully synthesized using a pyrolysis method with Borassus flabellifer vinegar (BFV) as the precursor. All the samples were characterized using ultraviolet-visible spectrophotometry (UV-Vis), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The antibacterial activities of BFV-GQDs against strains of Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) were determined using the agar well diffusion method for preliminary screening, while minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the broth macro-dilution method. The zones of inhibition were compared with those of citric acid–graphene quantum dots (CA-GQDs). It was observed that the synthesized BFV-GQDs demonstrated excellent antibacterial activity against Staphylococcus aureus (82.3%) and good antibacterial activity against Escherichia coli (73.3%). The MIC of BFV-GQDs against E. coli was 6.25 mg/mL and S. aureus was 12.5 mg/mL, whereas the MBC of BFV-GQDs against E. coli was 12.5 mg/mL and S. aureus was 25.0 mg/mL.

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SINTESIS NANOPARTIKEL KOBALT FERRIT (CoFe2O4) MENGGUNAKAN EKSTRAK DAUN BINAHONG (Anredera cordifolia (Ten) Steenis) DAN APLIKASINYA SEBAGAI ANTIBAKTERI

CHEMISTRY PROGRESS ◽

10.35799/cp.12.1.2019.27919 ◽

2020 ◽

Vol 12 (1) ◽

Author(s):

Charissa L. Luntungan ◽

Henry F. Aritonang ◽

Vanda S. Kamu

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Leaf Extract ◽

Antibacterial Activities ◽

Clear Zone ◽

Cofe2o4 Nanoparticles ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria

ABSTRAKTelah dilakukan penelitian mengenai sintesis nanopartikel CoFe2O4 menggunakan ekstrak daun binahong (Anredera cordifolia (Ten) Steenis). dengan variasi perbandingan mol (Co(NO3)2.6H2O) : (Fe(NO3)3.9H2O) = 1:1 dalam 15 mL. Nanopartikel tersebut dikarakterisasi menggunakan XRD dan SEM serta diuji aktivitas antibakterinya. Uji aktivitas antibakteri mengunakan bakteri Staphylococcus aureus (gram-positif) dan Escherichia coli (gram-negatif). Hasil penelitian menunjukan bahwa ukuran nanopartikelnya adalah 37,52 nm. Kemudian aktivitas antibakteri diketahui berdasarkan luasnya zona bening yang terbentuk dengan hasil diperoleh sebesar 15 mm untuk bakteri E.coli dan 20 mm untuk bakteri S.aureus. Daun Binahong sendiri memiliki sifat sebagai antibakteri dengan hasil yang didapat adalah 8,25 mm untuk bakteri E.coli dan 10,25 mm untuk bakteri S.aureus. Hal ini menunjukan bahwa nanopartikel CoFe2O4 1 : 1 dalam 15 mL ekstrak dapat digunakan sebagai antibakteriABSTRACTIt has been done research on the synthesis of CoFe2O4 nanoparticles using binahong (Anredera cordifolia (Ten) Steenis) leaf extract. With comparison mol variation of (Co(NO3)2.6H2O) : (Fe(NO3)3.9H2O) = 1:1 in 15 mL extract. The nanoparticles were characterized using XRD and SEM and tested for their antibacterial activities. Test antibacterial activity using Staphylococcus aureus (gram-positive) bacteria and Escherichia coli (gram-negative). The results showed that the nanoparticle size was 37.52 nm. Antibacterial activity is known by the extent of the clear zone formed with the results obtained by 15 mm for the E. coli bacteria and 20 mm for the bacteria S. aureus. The leaf Binahong itself has a trait as an antibacterial with the results obtained is 8.25 mm for the bacteria E. coli and 10.25 mm for the S.aureus bacteria. This suggests that the CoFe2O4 nanoparticles 1:1 mol in 15 mL extrack are used as antibacterial.

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