scholarly journals In vitro Anti-Bacterial Activity of Oral Herbal Medicines Assessed by Agar Well Diffusion and Broth Micro-Dilution Methods

2016 ◽  
pp. 15-19
Author(s):  
Kamal Kanta Das ◽  
Mrityunjoy Acharjee ◽  
Rashed Noor
Keyword(s):  
Antibacterial Activity ◽  
Herbal Medicines ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Drug Resistance Pattern ◽  
Viable Bacteria ◽  
Agar Well Diffusion Assay ◽  
Staphylococcus Spp

Recently antibacterial activity of ten commonly available oral herbal medicines has tested in our laboratory. Current investigation further endeavoured to compute the microbial propagation in six more oral herbal medicines, including the drug resistance pattern of the microbial isolates, and antibacterial potential of the medicines by employing both agar well diffusion method and broth micro-dilution procedure to determine the minimum inhibitory concentration (MIC). Among the 30 samples of 6 categories studied, the total viable bacteria were found within the range of 104-107 cfu/ml, while the presence of fungi was noticed only in 3 samples up to 105 cfu/ml. All samples were found to be contaminated with Staphylococcus spp., 2 samples with Escherichia coli and 1 sample was found to be contaminated with Klebsiella spp. Most of the isolates showed resistance against commonly used 13 antibiotics; 80% isolates were found to be multidrug-resistant (MDR). All samples exhibited antibacterial activity with their MIC values up to 55 mg/ml. However, using the agar well diffusion assay, antibacterial activity was detected only in case of only 1 sample.Bangladesh J Microbiol, Volume 32, Number 1-2,June-Dec 2015, pp 15-19

scholarly journals Antibiofilm and antivirulence potential of silver nanoparticles against multidrug-resistant Acinetobacter baumannii

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helal F. Hetta ◽  
Israa M. S. Al-Kadmy ◽  
Saba Saadoon Khazaal ◽  
Suhad Abbas ◽  
Ahmed Suhail ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Infection Model ◽  
The Impact

AbstractWe aimed to isolate Acinetobacter baumannii (A. baumannii) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy. A. baumannii (n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE and traT) were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of A. baumannii with human fibroblast skin cell line HFF-1 or Vero cell lines. A. baumannii had high level of resistance to antibiotics. Most of the isolates harbored the fimH, afa/draBC, cnf1, csgA and cnf2, and the majority of A. baumannii produced strong biofilms. AgNPs inhibited the growth of A. baumannii efficiently with MIC ranging from 4 to 25 µg/ml. A. baumannii showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of kpsMII , afa/draBC,bap, OmpA, and csuA/B genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular A. baumannii. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.

scholarly journals Molecular Composition and Antibacterial Effect of Five Essential Oils Extracted from Nigella sativa L. Seeds against Multidrug-Resistant Bacteria: A Comparative Study

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mohammed Dalli ◽  
Salah-eddine Azizi ◽  
Hind Benouda ◽  
Ali Azghar ◽  
Maroua Tahri ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oils ◽  
Nigella Sativa ◽  
Multidrug Resistant ◽  
Climatic Conditions ◽  
Diffusion Method ◽  
Resistant Bacteria ◽  
Microdilution Method

Nigella sativa L. (NS) and its volatile compounds are well known for their broad spectrum of effects. This study aimed to investigate the variability of the chemical composition and the in vitro antibacterial activity of five essential oils (Eos) originated from Morocco, Saudi Arabia, Syria, India, and France. These five samples were grown under different edaphic and climatic conditions. The agar diffusion method and microdilution method in 96-well plates were used to test the sensitivity of multidrug-resistant strains clinically isolated from patients (methicillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii), for the determination of the minimum inhibitory concentration and bactericidal concentration. Among all the investigated Eos, the monoterpenes were highly present in the chemical composition. Moroccan, Saudi Arabian, and Syrian seeds were characterized by the presence α-phellandrene (20.03–30.54%), β-cymene (12.31–23.82 %), and 4−caranol (9.77–14.27%). The Indian seeds were rich with 4-caranol (18.81%), β-cymene (14.22%), α-phellandrene (10.58%), and β-chamigrene (9.54%), while France NS was rich with estragole (20.22%) and D-limonene (14.63%). The minimum inhibitory (MIC) and bactericidal concentration (MBC) obtained for the four Eos (with the exception of France because of the low yield) tested were ranging from 3 to 40 μl/ml. Gram-positive (+) bacteria were slightly sensitive to the Eos tested than the Gram-negative (−) bacteria. The results of this study showed that the Eos of NS seeds show interesting antibacterial activity which could be associated to the existence of different bioactive compounds. Indeed, these compounds can be used for preventive or curative purposes in the face of the noncontrolled emergence of resistance to antibiotics.

scholarly journals Potential of Bacterial Cellulose Chemisorbed with Anti-Metabolites, 3-Bromopyruvate or Sertraline, to Fight against Helicobacter pylori Lawn Biofilm

2020 ◽  
Vol 21 (24) ◽  
pp. 9507 ◽  
Author(s):  
Paweł Krzyżek ◽  
Grażyna Gościniak ◽  
Karol Fijałkowski ◽  
Paweł Migdał ◽  
Mariusz Dziadas ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibacterial Activity ◽  
Bacterial Cellulose ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Continuous Exposure ◽  
Disk Diffusion Method ◽  
Bacterial Morphology ◽  
H Pylori

Helicobacter pylori is a bacterium known mainly of its ability to cause persistent inflammations of the human stomach, resulting in peptic ulcer diseases and gastric cancers. Continuous exposure of this bacterium to antibiotics has resulted in high detection of multidrug-resistant strains and difficulties in obtaining a therapeutic effect. The purpose of the present study was to determine the usability of bacterial cellulose (BC) chemisorbed with 3-bromopyruvate (3-BP) or sertraline (SER) to act against lawn H. pylori biofilms. The characterization of BC carriers was made using a N2 adsorption/desorption analysis, tensile strength test, and scanning electron microscopy (SEM) observations. Determination of an antimicrobial activity was performed using a modified disk-diffusion method and a self-designed method of testing antibacterial activity against biofilm microbial forms. In addition, bacterial morphology was checked by SEM. It was found that BC disks were characterized by a high cross-linking and shear/stretch resistance. Growth inhibition zones for BC disks chemisorbed with 2 mg of SER or 3-BP were equal to 26.5–27.5 mm and 27–30 mm, respectively. The viability of lawn biofilm H. pylori cells after a 4-h incubation with 2 mg SER or 3-BP chemisorbed on BC disks was ≥4 log lower, suggesting their antibacterial effect. SEM observations showed a number of morphostructural changes in H. pylori cells exposed to these substances. Concluding, SER and 3-BP chemisorbed on BC carriers presented a promising antibacterial activity against biofilm H. pylori cells in in vitro conditions.

scholarly journals Assessment of the Microbiological Quality of Ready-To Fry Frozen Chicken-Based Snack Items Sold in Bangladesh

2021 ◽  
pp. 52-56
Author(s):  
Anamika Chakrabarty ◽  
Tamanna Islam ◽  
Saurab Kishore Munshi
Keyword(s):  
Foodborne Pathogens ◽  
Microbiological Quality ◽  
Multidrug Resistant ◽  
Resistance Pattern ◽  
Microbiological Analysis ◽  
Chicken Nuggets ◽  
Salmonella Spp ◽  
Viable Bacteria ◽  
Bacteria And Fungi ◽  
Staphylococcus Spp

Microorganisms that are capable of spoiling the product during chill storage as well as several foodborne pathogens can be present in frozen snacks. The present study attempted to investigate the presence of microbial contaminants along with their antibiotic resistance pattern in frozen snacks. In this regard, a total of 15 ready-to-fry frozen chicken-based snack items including three each of chicken pops, chicken samosa, chicken lemongrass lollypop, chicken nuggets and chicken meatball were collected from super shops of Dhaka, Bangladesh. Microbiological analysis revealed that all the samples were highly contaminated with total viable bacteria and fungi in an average of 6 and 4 log cfu/g, respectively which exceeded the standard microbial limit. Klebsiella spp., Staphylococcus spp. and Pseudomonas spp. were encountered in all samples. E. coli, Vibrio spp. and Salmonella spp. were also found in a majority of the samples. Besides, all the isolates were found to be multidrug-resistant. The isolates showed almost 100% resistance against Cefuroxime and Cefixime. A higher proportion of resistance was also reported against Vancomycin and Azithromycin. Whereas, Gentamycin, Ceftriaxone, Colistin and Levofloxacin sensitivity were found in all the isolates. Such chicken-based frozen snack items contaminated with multi-drug resistant microorganisms could be potential vehicles for transmitting food-borne diseases.

scholarly journals Promising Antibacterial Effect of Copper Oxide Nanoparticles against Several Multidrug Resistant Uropathogens

2018 ◽  
Vol 24 (3) ◽  
pp. 213-218 ◽  
Author(s):  
Hadi Sedigh Ebrahim-Saraie ◽  
Hamid Heidari ◽  
Vahid Rezaei ◽  
Seyed Mohammad Javad Mortazavi ◽  
Mohammad Motamedifar
Keyword(s):  
Antibacterial Activity ◽  
Copper Oxide ◽  
Multidrug Resistant ◽  
Copper Oxide Nanoparticles ◽  
Diffusion Method ◽  
Multiple Drug ◽  
Oxide Nanoparticles ◽  
Cuo Nps ◽  
Conventional Antibiotics

Background: Recently, nanotechnology has been demonstrated to be a promising application to overcome the problem of antibiotic resistance. In the present study, we aimed to determine the antibacterial activity of copper oxide nanoparticles (CuO NPs) on several multiple-drug resistant (MDR) uropathogenic strains. Methods: This in vitro case-control study was performed on 4 uropathogenic bacteria including Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa. The antibacterial property was evaluated by well diffusion method at different concentrations of CuO NPs. Results: Overall, NPs concentration of 10, 25 and 50 µg/mL showed the remarkable antibacterial activity. A lower effect was seen against S. aureus strains. CuO NPs exhibited maximum bacterial growth inhibition against E. faecalis strains. In most of the cases, the zone of inhibition in 50 µg/mL concentration was closest to control positive antibiotics. Conclusion: In summary, CuO NPs as an alternative to conventional antibiotics that are currently used showed dose-dependent on antibacterial activity against different uropathogens, specificity towards pathogenic Gram-positive bacteria. This promising antibacterial activity of CuO NPs suggesting the development of NPs coatings on the different surface of biomedical materials for applications in different antimicrobial control systems.

scholarly journals In vitro assessment of the antibacterial activity of combinations of methanolic extracts of Mangifera indica L. bark and Psidium guajava L. leaf on multidrug-resistant Pseudomonas aeruginosa

2021 ◽  
Vol 18 (2) ◽  
pp. 87-94
Author(s):  
Churchill Akena ◽  
Gloria Maxensia Akampa ◽  
Edson Ireeta Munanura ◽  
Robert BD Otto ◽  
Bruhan Kaggwa ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Mangifera Indica ◽  
Psidium Guajava ◽  
Multidrug Resistant ◽  
Positive Control ◽  
Diffusion Method ◽  
Methanolic Extracts ◽  
The Individual

Pseudomonas aeruginosa causes various infections in humans both in hospital and community settings. Mangifera indica Linnaeus bark and dry Psidium guajava Linnaeus leaves have individually demonstrated activity against P. aeruginosa. This study aimed to assess the combined antibacterial activity of methanolic extracts of dry M. indica bark and dry P. guajava leaves on Multidrug-Resistant P. aeruginosa. Different proportion combinations of P. guajava and M. indica were assessed for antipseudomonal activity using Agar well diffusion method. Colistin was the positive control. The Fractional Inhibitory Concentration Index (FICI) was also determined. The combination of methanolic extracts of P. guajava leaves (35 mg/mL) and M. indica bark (6.25 mg/mL) had a superior antibacterial effect on Multidrug-Resistant P. aeruginosa when compared with the individual extracts used alone (p˂0.05), save for P. guajava (100 mg/mL) (p = 0.1373). Colistin was significantly more active on MDR P. aeruginosa than all the test extract concentrations used. This combination of M. indica bark and P. guajava leaves methanolic extracts had a FICI of 0.2434. This study demonstrates that the combination of P. guajava leaves (35 mg/mL) and M. indica bark (6.25 mg/mL) has synergistically enhanced activity against MDR P. aeruginosa. Keywords: Antipseudomonal, MDR Pseudomonas aeruginosa, Mangifera indica, and Psidium guajava

scholarly journals Surgical Site Infections and Antimicrobial Resistance Pattern

2017 ◽  
Vol 15 (2) ◽  
pp. 120-123 ◽  
Author(s):  
Raskin Chaudhary ◽  
Shrawan Kumar Thapa ◽  
Jid Chani Rana ◽  
Pradeep Kumar Shah
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacterial Growth ◽  
Surgical Site Infections ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Medical Expense ◽  
Gram Negative

Background: Post-operative surgical site infections (SSIs) are among the leading cause of morbidity and increased medical expense. The aim of this study is to isolate identify and study antimicrobial susceptibility pattern of microorganism from surgical wound of admitted patients.Methods: This retrospective study was carried at the Microbiology Laboratory of Bharatpur hospital, Nepal, from May 2015 to October 2015. The pus samples were cultured and antibiotic susceptibility determined in vitro by Kirby Bauer’s disc diffusion method following clinical and Laboratory Standards Institute (CLSI) 2014 recommendation.Results: Of the total 250 samples, 194 (77.6%) showed bacterial growth. Staphylococcus aureus was 47.4% and Escherichia coli 20.60 %. Of 194 isolates 39.2% were multi drug resistant. Amikacin was sensitive in 93.1% of Gram positive isolates and 81.8% of gram negative isolates.Conclusions: Bacterial growth is common in surgical site. Staphylococcus aureus and Escherichia coli were multidrug resistant. Grampositive and gram negative isolates were commonly sensitive to Amikacin.

Distribution of Pathogens Involved in Infections in Oncological Patients and their Antibiotic Resistance Profile

2020 ◽  
Vol 70 (12) ◽  
pp. 4287-4294
Keyword(s):  
Antibiotic Resistance ◽  
Cancer Patients ◽  
Bacterial Pathogen ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Antibiotic Resistance Profile ◽  
Oncological Patients ◽  
Eastern European Countries ◽  
Klebsiella Spp

Cancer is the second leading cause of death in Romania and worldwide. Cancer patients are at increasing risk of acquiring bacterial infection with multi-resistant germs, including multidrug-resistant (MDR) strains of Gram-negative bacteria involved in nosocomial infection. Romania is one of the South-Eastern European countries with one of the highest prevalence rates of MDR pathogens. To determine the resistance pattern of bacterial profile and antibiotic resistance pattern in cancer patients admitted at the County Emergency Clinical Hospital Craiova, Romania. A retrospective study of bacterial pathogens was carried out on 90 adult cancer patients admitted from January to December 2018. The analysis of the resistance patterns for the action of the appropriate antibiotics was performed using Vitek 2 Compact system and diffusion method. In this study there were analysed 92 samples from 90 oncological patients (37-86 years). A total of 157 bacterial isolates were obtained, of which 37 strains of Staphylococcus aureus (23.56%), followed by Streptococcus pneumoniae (23- 14.64%), Klebsiella spp. and Escherichia coli (22 - 14,01%). The most common isolates were from respiratory tract (86 isolates - 54.77%). High rates of MDR were found for E. coli (63.63%), MRSA (61,11%) and Klebsiella spp. (54,54%), while one third of the isolated strains of Pseudomonas aeruginosa, Acinetobacter spp. and Proteus spp. were MDR. The findings of this study may be the basis for further more extensive studies highlighting the germs involved in the infectious pathology of cancer patients, in order to determine the antimicrobial resistance and to improve the methods of prophylaxis and treatment. Keywords: multidrug resistance (MDR), cancer patients, bacterial pathogen

scholarly journals Evaluation of the in vitro antibacterial activity of some essential oils and their blends against Staphylococcus spp. isolated from episodes of sheep mastitis

2021 ◽  
Author(s):  
Filippo Fratini ◽  
Margherita Giusti ◽  
Simone Mancini ◽  
Francesca Pisseri ◽  
Basma Najar ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Essential Oils ◽  
Diffusion Method ◽  
Minimal Bactericidal Concentration ◽  
Coagulase Negative Staphylococci ◽  
Disk Diffusion Method ◽  
In Vitro Antibacterial Activity ◽  
High Concentrations ◽  
Thymus Serpyllum

AbstractStaphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex.

scholarly journals 1293. Sulbactam-durlobactam is active against recent, multi-drug resistant Acinetobacter baumannii clinical isolates from the Middle East

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S662-S662
Author(s):  
Alita Miller ◽  
Sarah McLeod ◽  
Samir Moussa ◽  
Meredith Hackel
Keyword(s):  
Antibacterial Activity ◽  
Middle East ◽  
Acinetobacter Baumannii ◽  
United Arab Emirates ◽  
Blood Stream ◽  
Multidrug Resistant ◽  
Clinical Isolates ◽  
Surveillance Systems ◽  
Spectrum Activity

Abstract Background The incidence of infections caused by multidrug-resistant (MDR) Acinetobacter baumannii (Ab) is increasing at an alarming rate in certain regions of the world, including the Middle East. Sulbactam (SUL) has intrinsic antibacterial activity against Ab; however, the prevalence of β-lactamases in Ab has limited its therapeutic utility. Durlobactam (DUR, formerly ETX2514) is a diazabicyclooctenone β-lactamase inhibitor with broad-spectrum activity against Ambler class A, C and D β-lactamases that restores SUL activity in vitro against MDR Ab. SUL-DUR is an antibiotic designed to treat serious infections caused by Acinetobacter, including multidrug-resistant strains, that is currently in Phase 3 clinical development. In global surveillance studies of >3600 isolates from 2012-2017, the MIC90 of SUL-DUR was 2 mg/L. Although surveillance systems to monitor MDR infections in the Middle East are currently being established, quantitative, prevalence-based data are not yet available. Therefore, the potency of SUL-DUR was determined against 190 recent, diverse Ab clinical isolates from this region. Methods 190 Ab isolates were collected between 2016 - 2018 from medical centers located in Israel (N = 47), Jordan (N = 36), Qatar (N = 13), Kuwait (N = 42), Lebanon (N = 8), Saudi Arabia (N = 24) and United Arab Emirates (N = 20). Seventy-five percent and 20.5% of these isolates were from respiratory and blood stream infections, respectively. Susceptibility to SUL-DUR and comparator agents was performed according to CLSI guidelines, and data analysis was performed using CLSI and EUCAST breakpoint criteria where available. Results This collection of isolates was 86% carbapenem-resistant and 90% sulbactam-resistant (based on a breakpoint of 4 mg/L). The addition of SUL-DUR (fixed at 4 mg/L) decreased the sulbactam MIC90 from 64 mg/L to 4 mg/L. Only 3 isolates (1.6%) had SUL-DUR MIC values of > 4 mg/L. This potency was consistent across countries, sources of infection and subsets of resistance phenotypes. Conclusion SUL-DUR demonstrated potent antibacterial activity against recent clinical isolates of Ab from the Middle East, including MDR isolates. These data support the global development of SUL-DUR for the treatment of MDR Ab infections. Disclosures Alita Miller, PhD, Entasis Therapeutics (Employee) Sarah McLeod, PhD, Entasis Therapeutics (Employee) Samir Moussa, PhD, Entasis Therapeutics (Employee)

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