scholarly journals In vitro antimicrobial activity of Salvadora persica extract on Helicobacter pylori strains isolated from duodenal ulcer biopsies

2012 ◽  
Vol 3 (1) ◽  
pp. 9 ◽  
Author(s):  
Ehsan Mirkamandar ◽  
Mohammad Reza Shakibaie ◽  
Saeed Adeli ◽  
Mitra Mehrabani ◽  
Mohammad Mehdi Hayatbakhsh ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Duodenal Ulcer ◽  
Helicobacter Pylori ◽  
Dilution Method ◽  
Minimal Bactericidal Concentration ◽  
Agar Dilution Method ◽  
Zone Of Inhibition ◽  
Salvadora Persica ◽  
H Pylori

The aim of this study was to evaluate the <em>in vitro</em> antimicrobial activity of a methanolic extract of <em>Salvadora persica</em> solution on <em>Helicobacter pylori</em> isolated from duodenal ulcer. Over 22 strains of H. pylori were isolated from duodenal ulcer from August 2010 to June 2011. The <em>S. persica</em> stem was purchased from a local herb market and finely powdered. Extraction was performed with 60% methanol using a soxhlet extractor for 48 h until the solvent turned colorless while being incubated in an oven at 40°C for 48 h till dried. Dry powder was used to determine antimicrobial activity by the agar ditch method. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the extract were determined by the agar dilution method. At concentrations of 10, 100, 200, 500 µg/mL, no zone of inhibition around the ditches was observed while a clear zone of inhibition (12 mm) was detected at 1000 µg/mL concentration for all the isolates. The best antimicrobial activity was observed at MIC 1000 µg/mL (P≤0.05). Furthermore, 10 out of 22 isolates were inhibited at 750 µg/mL of the extract. The MBC results showed that at a concentration of 1000 µg/mL all cells were dead while at a concentration of 750 µg/mL of<em> S. persica </em>a few <em>H. pylori</em> cells were still able to form colonies on Brucella agar supplemented with sheep red blood cells and antibiotics. From the above results it can be concluded that high concentration of S.persica could inhibit the growth of H. pylori and MIC and MBC were similar at that concentration.

Activity of Bulgarian propolis against 94 Helicobacter pylori strains in vitro by agar-well diffusion, agar dilution and disc diffusion methods

2005 ◽  
Vol 54 (5) ◽  
pp. 481-483 ◽  
Author(s):  
Lyudmila Boyanova ◽  
Galina Gergova ◽  
Rossen Nikolov ◽  
Sirigan Derejian ◽  
Elena Lazarova ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Growth Inhibition ◽  
Biological Effects ◽  
Diffusion Method ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Propolis Extract ◽  
Agar Dilution ◽  
H Pylori

Propolis exhibits antimicrobial, anti-inflammatory and other biological effects. The aim of this study was to evaluate the activity of 30 % ethanolic extract of Bulgarian propolis against 94 Helicobacter pylori strains by three methods. By the agar-well diffusion method, only 13.8 % of the strains exhibited no inhibition by 30 μl propolis extract (containing 9 mg propolis) and all isolates were inhibited to some extent by 90 μl of the extract (27 mg propolis) per well. The mean diameters of growth inhibition by 30, 60 or 90 μl propolis extract or 30 μl 96 % ethanol per well were 16.8, 19.2, 27.5 and 8.3 mm, respectively. The propolis extract was more active than the ethanol (P < 0.001). With 90 μl propolis extract per well, 69.4 % of the strains exhibited large diameters of growth inhibition (⩾20 mm) versus 26.6 % with 30 μl per well (P < 0.001). With moist propolis discs, inhibition was detected in more strains (92.1 %) than with dried discs (78.2 %, P < 0.05), with mean inhibitory diameters of 18.7 and 13.8 mm, respectively. By the agar dilution method, 100 and 300 μg propolis ml−1 inhibited the growth of 57.1 % and 76.2 %, respectively, of the 21 strains tested. In conclusion, Bulgarian propolis had a strong and dose-dependent activity against most of the H. pylori strains tested. Although the effect of propolis on H. pylori in vitro is promising, further microbiological, pharmacological and clinical trials are required.

scholarly journals The Antibacterial Activity of Mass Galla Chinesis et Camelliae Fermentata on Helicobacter pylori Infection

2018 ◽  
Vol 2018 ◽  
pp. 1-6
Author(s):  
Jing Yu ◽  
Hui Ye ◽  
Jiang Li ◽  
Ning Li ◽  
Zong-ming Shi ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Rapid Urease Test ◽  
Dosage Group ◽  
Urease Test ◽  
H Pylori ◽  
Time Kill

Mass Galla chinesis et camelliae Fermentata (Chinese gall leaven, CGL) was investigated for activities against Helicobacter pylori (H. pylori) both in vitro and in vivo. The agar dilution method and time-kill curves, as in vitro assays and an in vivo study using a Kunming mice model, were performed. CGL demonstrated a strong anti-Helicobacter pylori activity in vitro with the minimal inhibitory concentrations (MICs) against multiple H. pylori strains of 0.5~8 mg/ml and the decreasing trend time-kill curves when increasing CGL concentrations. H. pylori eradication rates in vivo were evaluated based on rapid urease test (RUT) and histopathologic criteria. Results revealed that the eradication rates in the CGL groups were 40% (4/10) in the high dosage group, 33% (4/11) in the medium dosage group, and 18% (2/11) in the low dosage group, with the difference between the high dosage and H. pylori control groups being significant (P=0.035). The H. pylori colonization scores could be reduced partly by CGL. These in vivo results demonstrated that CGL in a rationally high dosage might be the most effective.

scholarly journals Helicobacter pylori antibiotic resistance in Brazil: clarithromycin is still a good option

2011 ◽  
Vol 48 (4) ◽  
pp. 261-264 ◽  
Author(s):  
Jaime Natan Eisig ◽  
Fernando Marcuz Silva ◽  
Ricardo Correa Barbuti ◽  
Tomás Navarro-Rodriguez ◽  
Joaquim Prado P Moraes-Filho ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Susceptibility ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Upper Gastrointestinal Endoscopy ◽  
Test Results ◽  
Primary Resistance ◽  
Agar Dilution ◽  
H Pylori

CONTEXT: The antibiotic susceptibility is the cornerstone for the eradication therapies of Helicobacter pylori. OBJECTIVES: To evaluate the prevalence of primary resistance of H. pylori was evaluated in an urban Brazilian population. METHODS:H. pylori isolates were obtained from patients submitted to an upper gastrointestinal endoscopy for the evaluation of dyspeptic symptoms. Biopsies from antrum, corpus and fundus were taken to determine the antibiotic susceptibility of H. pylori isolates. The minimal inhibitory concentration of furazolidone and bismuth were routinely determined by agar dilution method and the minimal inhibitory for amoxicillin, clarithromycin, tetracycline, levofloxacin, and metronidazole were routinely determined with the E-test. RESULTS: Fifty-four patients were included. In vitro antimicrobial susceptibility of H. pylori strains were obtained from 39 patients. Resistance to metronidazole was detected in 20 patients (51%), to clarithromycin in 3 patients (8%), to levofloxacin in 9 patients (23%) and to bismuth in 2 patients (5%). There was no observed resistance to amoxicillin, tetracycline or furazolidone. CONCLUSION: Due to the low amoxicillin and clarithromycin resistance observed in this study, therapies using these antimicrobials remain appropriated first-line H. pylori therapy.

scholarly journals Potential of FTIR-Spectroscopy for Drugs Screening against Helicobacter pylori

Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 897
Author(s):  
Pedro Sousa Sampaio ◽  
Cecília R. C. Calado
Keyword(s):  
Helicobacter Pylori ◽  
Ftir Spectroscopy ◽  
Partial Least Square ◽  
Least Square ◽  
New Drugs ◽  
Partial Least Square Regression ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Molecular Fingerprint ◽  
H Pylori

Helicobacter pylori colonizes the human stomach of half of the world’s population. The infection if not treated, persists through life, leading to chronic gastric inflammation, that may progress to severe diseases as peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. The first line of treatment, based on 7 to 21 days of two antibiotics associated with a proton pump inhibitor, is, however, already failing most due to patient non-compliance that leads to antibiotic resistance. It is, therefore, urgent to screen for new and more efficient antimicrobials against this bacterium. In this work, Fourier Transform Infrared (FTIR) spectroscopy was evaluated to screen new drugs against H. pylori, in rapid (between 1 to 6 h), and high-throughput mode and based on a microliter volume processes in relation to the agar dilution method. The reference H. pylori strains 26,695 and J99, were evaluated against a peptide-based antimicrobial and the clinical antibiotic clarithromycin, respectively. After optimization of the assay conditions, as the composition of the incubation mixture, the time of incubation, and spectral pre-processing, it was possible to reproducibly observe the effect of the drug on the bacterial molecular fingerprint as pointed by the spectra principal component analysis. The spectra, obtained from both reference strains, after its incubation with drugs concentrations lower than the MIC, presented peak ratios statistically different (p < 0.05) in relation to the bacteria incubated with drugs concentrations equal or higher to the MIC. It was possible to develop a partial least square regression model, enabling to predict from spectra of both bacteria strains, the drug concentration on the assay, with a high correlation coefficient between predicted and experimental data (0.91) and root square error of 40% of the minimum inhibitory concentration. All this points to the high potential of the technique for drug screening against this fastidious growth bacterium.

scholarly journals Antimicrobial Sensitivity Pattern of Helicobacter pylori Isolates among Subgroup of Bangladeshi Patients

2014 ◽  
Vol 8 (2) ◽  
pp. 49-52
Author(s):  
MMSU Islam ◽  
Shamsun Nahar ◽  
Mst Naznin Sarker ◽  
ASM Salimullah ◽  
Mohammad Asadur Rahman ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Diarrhoeal Disease ◽  
Cross Sectional Study ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Cross Sectional ◽  
Antimicrobial Sensitivity ◽  
Sensitivity Pattern ◽  
H Pylori ◽  
Medical University

This cross sectional study was carried out at Bangabandhu Sheikh Mujib Medical University (BSMMU) and International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B) from July 2008 to September 2009. Aim of the study was to find out the antimicrobial susceptibility profile of Helicobacter pylori isolates from dyspeptic patients. Total 224 dyspeptic patients from Out Patient Department (OPD) of BSMMU were initially enrolled after informed written consent. After upper GI endoscopy 157 patients were finally included who had erosions, ulcers or atrophic changes in the stomach or duodenum. Two biopsy samples were taken from each of them. Samples were incubated at 37°C in a double gas incubator with 5%O2, 10%CO2 and 85%N2. Total 82 (52.23%) samples were found positive for H. pylori. Isolated organisms were then tested for sensitivity to Amoxicillin, Clarithromycin, Tetracycline, Levofloxacin and Metronidazole by Agar dilution method. Among 82 patients 51(62.2%) were male and 31(37.8) were female with a male:female ratio 1.6:1. Patients were categorized into two groups one having gastric or duodenal ulcer (30.5%) and other having no ulcer (69.5%). Among these isolates 92.7% were sensitive to Amoxicillin, 89% to Clarithromycin, 81.7% to Tetracycline, 80.5% to Levofloxacin and only 26.8% to Metronidazole. Beside these, 81.7% isolates were sensitive to both Amoxicillin and Clarithromycin, 74.4% to Amoxicillin and Tetracycline, 73.2% to Amoxicillin and Levofloxacin, 72% to Clarithromycin and Tetracycline, 59% to Clarithromycin and Levofloxacin and 51% to Tetracycline and Levofloxacin DOI: http://dx.doi.org/10.3329/fmcj.v8i2.20280 Faridpur Med. Coll. J. 2013;8(2): 49-52

scholarly journals Helicobacter pylori antibiotic susceptibility patterns in Bangladesh: Emerging levofloxacin resistance

2016 ◽  
Vol 10 (03) ◽  
pp. 245-253 ◽  
Author(s):  
Hafeza Aftab ◽  
Muhammad Miftahussurur ◽  
Phawinee Subsomwong ◽  
Faruque Ahmed ◽  
AK Azad Khan ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Triple Therapy ◽  
Antibiotic Susceptibility ◽  
Resistance Rate ◽  
Resistance Pattern ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Peptic Ulcers ◽  
H Pylori ◽  
Resistance Rates

Introduction: The most recent study to report Helicobacter pylori antibiotic resistance rates in Bangladesh was published 15 years ago and did not include levofloxacin. We therefore aimed to determine the current antibiotic susceptibility of H. pylori to amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin in Bangladesh. Methodology: This study included 133 consecutive patients who underwent endoscopy examination at Dhaka Medical College in November 2014. The serial two-fold agar dilution method was used to determine the minimum inhibitory concentrations of the five antibiotics. Results: Among 56 cultured strains, H. pylori showed high rates of resistance to clarithromycin and metronidazole (39.3% and 94.6%, respectively). Moreover, levofloxacin showed an emerging antimicrobial resistance pattern (66.1%), which was higher in patients with gastritis than that in those with peptic ulcers (p = 0.02). The resistance rate of levofloxacin was significantly higher in patients living in Dhaka city compared to those living in the village (p = 0.049). However, amoxicillin and tetracycline resistance rates were very low. Resistance to both metronidazole and levofloxacin was most commonly observed. Conclusions: The rates of resistance to clarithromycin, metronidazole, and levofloxacin were high in Bangladesh, which suggests that triple therapy based on these drugs may not be useful as first-line therapies in Bangladesh. Alternative strategies such as furazolidone-based triple therapy, bismuth-based quadruple therapies, or sequential therapy may be more effective for patients in in Bangladesh.

scholarly journals In Vitro Probiotic Potential of Lactic Acid Bacteria Isolated from Aguamiel and Pulque and Antibacterial Activity Against Pathogens

2019 ◽  
Vol 9 (3) ◽  
pp. 601 ◽  
Author(s):  
Alicia Cervantes-Elizarrarás ◽  
Nelly Cruz-Cansino ◽  
Esther Ramírez-Moreno ◽  
Vicente Vega-Sánchez ◽  
Norma Velázquez-Guadarrama ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Helicobacter Pylori ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Eradication Therapy ◽  
Antimicrobial Effect ◽  
E Coli ◽  
Probiotic Potential ◽  
H Pylori

Probiotics can act as a natural barrier against several pathogens, such Helicobacter pylori, a bacterium linked to stomach cancer. The aim of the present study was to isolate and identify lactic acid bacteria (LAB) from pulque and aguamiel, and evaluate their probiotic potential and antimicrobial effect on Escherichia coli, Staphylococcus aureus, and Helicobacter pylori. Ten isolates were selected and evaluated for in vitro resistance to antibiotics and gastrointestinal conditions, and antimicrobial activity against E. coli and S. aureus and the effect on H. pylori strains. 16S rRNA identification was performed. Ten potential probiotic isolates were confirmed as belonging to the genera Lactobacillus and Pediococcus. All the strains were susceptible to clinical antibiotics, except to vancomycin. Sixty percent of the isolates exhibited antimicrobial activity against E. coli and S. aureus. The growth of H. pylori ATCC 43504 was suppressed by all the LAB, and the urease activity from all the H. pylori strains was inhibited, which may decrease its chances for survival in the stomach. The results suggest that LAB isolated from pulque and aguamiel could be an option to establish a harmless relationship between the host and H. pylori, helping in their eradication therapy.

scholarly journals High Prevalence of Antibiotic Resistance in Iranian Helicobacter pylori Isolates: Importance of Functional and Mutational Analysis of Resistance Genes and Virulence Genotyping

2019 ◽  
Vol 8 (11) ◽  
pp. 2004 ◽  
Author(s):  
Nastaran Farzi ◽  
Abbas Yadegar ◽  
Amir Sadeghi ◽  
Hamid Asadzadeh Aghdaei ◽  
Sinéad Marian Smith ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Rrna Genes ◽  
23S Rrna ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Gyra Gene ◽  
Therapeutic Regime ◽  
High Prevalence ◽  
H Pylori

The high prevalence of antibiotic resistance in Helicobacter pylori has become a great challenge in Iran. The genetic mutations that contribute to the resistance have yet to be precisely identified. This study aimed to investigate the prevalence of antibiotic resistance and virulence markers in Iranian H. pylori isolates and to analyze if there is any association between resistance and genotype. Antibiotic susceptibility patterns of 68 H. pylori isolates were investigated against metronidazole, clarithromycin, amoxicillin, rifampicin, ciprofloxacin, levofloxacin, and tetracycline by the agar dilution method. The frxA, rdxA, gyrA, gyrB, and 23S rRNA genes of the isolates were sequenced. The virulence genotypes were also determined using PCR. Metronidazole resistance was present in 82.4% of the isolates, followed by clarithromycin (33.8%), ciprofloxacin (33.8%), rifampicin (32.4%), amoxicillin (30.9%), levofloxacin (27.9%), and tetracycline (4.4%). Overall, 75% of the isolates were resistant to at least two antibiotics tested and considered as a multidrug resistance (MDR) phenotype. Most of the metronidazole-resistant isolates carried frameshift mutations in both frxA and rdxA genes, and premature termination occurred in positions Q5Stop and Q50Stop, respectively. Amino acid substitutions M191I, G208E, and V199A were predominantly found in gyrA gene of fluoroquinolone-resistant isolates. A2143G and C2195T mutations of 23S rRNA were found in four clarithromycin-resistant isolates. Interestingly, significant associations were found between resistance to metronidazole (MNZ) and cagA-, sabA-, and dupA-positive genotypes, with p = 0.0002, p = 0.0001, and p = 0.0001, respectively. Furthermore, a significant association was found between oipA “on” status and resistance to amoxicillin (AMX) (p = 0.02). The prevalence of H. pylori antibiotic resistance is high in our region, particularly that of metronidazole, clarithromycin, ciprofloxacin, and MDR. Simultaneous screening of virulence and resistance genotypes can help clinicians to choose the appropriate therapeutic regime against H. pylori infection.

scholarly journals In Vitro Activities of Linezolid Alone and in Combination with Amoxicillin, Clarithromycin, and Metronidazole againstHelicobacter pylori

2000 ◽  
Vol 44 (7) ◽  
pp. 1977-1979 ◽  
Author(s):  
Alexander M. Hirschl ◽  
Petra Apfalter ◽  
Athanasios Makristathis ◽  
Manfred L. Rotter ◽  
Margit Wimmer
Keyword(s):  
Helicobacter Pylori ◽  
Inhibitory Concentration ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Fractional Inhibitory Concentration ◽  
Agar Dilution

ABSTRACT Linezolid was tested against 70 strains of Helicobacter pylori by the agar dilution method. The MIC range and MICs at which 50 and 90% of strains were inhibited were 8 to 64, 16, and 32 μg/ml, respectively. With minimum and maximum fractional inhibitory concentration summation values of 0.31 and 2.50, respectively, the combination of linezolid with amoxicillin, clarithromycin, or metronidazole showed either partial synergy or indifference for the majority of strains.

Antagonism of Helicobacter pylori by Bacteriocins of Lactic Acid Bacteria

2003 ◽  
Vol 66 (1) ◽  
pp. 3-12 ◽  
Author(s):  
TAE-SEOK KIM ◽  
JI-WOON HUR ◽  
MYEONG-AE YU ◽  
CHAN-ICK CHEIGH ◽  
KYUNG-NAM KIM ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Helicobacter Pylori ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Inoculum Size ◽  
Strain Atcc ◽  
Initial Inoculum ◽  
H Pylori ◽  
Strain Dependent

Antimicrobial activity of seven bacteriocins produced by lactic acid bacteria against Helicobacter pylori strains (ATCC 43504, Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH [DSM] 4867, DSM 9691, and DSM 10242) was investigated in vitro using a broth microdilution assay. The bacteriocins chosen for the study were nisin A; lacticins A164, BH5, JW3, and NK24; pediocin PO2; and leucocin K. Antimicrobial activity of the bacteriocins varied among the H. pylori strains tested, of which strain ATCC 43504 was the most tolerant. Among the bacteriocins tested, lacticins A164 and BH5 produced by Lactococcus lactis subsp. lactis A164 and L. lactis BH5, respectively, showed the strongest antibacterial activity against H. pylori strains. MICs of the lacticins against H. pylori strains, when assessed by the critical dilution micromethod, ranged from 0.097 to 0.390 mg/liter (DSM strains) or from 12.5 to 25 mg/liter (ATCC 43504), supporting the strain-dependent sensitivity of the pathogen. Pediocin PO2 was less active than the lacticins against four strains of H. pylori, and leucocin K was the least active peptide, with no inhibition toward H. pylori ATCC 43504. Anti-Helicobacter activity of lacticin A164 was dependent on initial inoculum size as well as concentration of the bacteriocin added.

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