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

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.

Author(s):  
Dharmastuti Cahya Fatmarahmi ◽  
Ratna Asmah Susidarti ◽  
Respati Tri Swasono ◽  
Abdul Rohman

The study aims to develop an effective, efficient, and reliable method using Fourier Transform Infrared (FTIR) spectroscopy with Attenuated Total Reflection (ATR) combined with chemometric for identifying the synthetic drug in Indonesian herbal medicine known as Jamu. Jamu powders, Metamizole, and the binary mixture of Jamu and Metamizole were measured using FTIR-ATR at the mid-infrared region (4000-650 cm-1). The obtained spectra profiles were further analyzed by Principal Component Analysis, Partial Least Square Regression, Principal Component Regression, and Discriminant Analysis. Jamu Pegel Linu (JPL), Jamu Encok (JE), Jamu Sakit Pinggang (JSP), Metamizole (M), and adulterated Jamu by Metamizole were discriminated well on PCA score plot. PLSR and PCR showed the accuracy and precision data to quantify JPL, JE, and JSP, and each adulterated by M with R2 value > 0,995 and low value of RMSEC and RMSEP. Discriminant Analysis (DA) was successfully grouping Jamu and Metamizole without any misclassification. A combination of FTIR spectroscopy and chemometrics offered useful tools for detecting Metamizole in traditional herbal medicine.


Author(s):  
Anggita Rosiana Putri ◽  
Abdul Rohman ◽  
Sugeng Riyanto ◽  
Widiastuti Setyaningsih

Authentication of Patin fish oil (MIP) is essential to prevent adulteration practice, to ensure quality, nutritional value, and product safety. The purpose of this study is to apply the FTIR spectroscopy combined with chemometrics for MIP authentication. The chemometrics method consists of principal component regression (PCR) and partial least square regression (PLSR). PCR and PLSR were used for multivariate calibration, while for grouping the samples using discriminant analysis (DA) method. In this study, corn oil (MJ) was used as an adulterate. Twenty-one mixed samples of MIP and MJ were prepared with the adulterate concentration range of 0-50%. The best authentication model was obtained using the PLSR technique using the first derivative of FTIR spectra at a wavelength of 650-3432 cm-1. The coefficient of determination (R2) for calibration and validation was obtained 0.9995 and 1.0000, respectively. The value of root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) were 0.397 and 0.189. This study found that the DA method can group the samples with an accuracy of 99.92%.


2014 ◽  
Vol 8 (2) ◽  
pp. 49-52
Author(s):  
MMSU Islam ◽  
Shamsun Nahar ◽  
Mst Naznin Sarker ◽  
ASM Salimullah ◽  
Mohammad Asadur Rahman ◽  
...  

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


2016 ◽  
Vol 10 (03) ◽  
pp. 245-253 ◽  
Author(s):  
Hafeza Aftab ◽  
Muhammad Miftahussurur ◽  
Phawinee Subsomwong ◽  
Faruque Ahmed ◽  
AK Azad Khan ◽  
...  

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.


2019 ◽  
Vol 8 (11) ◽  
pp. 2004 ◽  
Author(s):  
Nastaran Farzi ◽  
Abbas Yadegar ◽  
Amir Sadeghi ◽  
Hamid Asadzadeh Aghdaei ◽  
Sinéad Marian Smith ◽  
...  

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.


2005 ◽  
Vol 54 (5) ◽  
pp. 481-483 ◽  
Author(s):  
Lyudmila Boyanova ◽  
Galina Gergova ◽  
Rossen Nikolov ◽  
Sirigan Derejian ◽  
Elena Lazarova ◽  
...  

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.


2021 ◽  
Vol 54 (4) ◽  
Author(s):  
Sandra Weigel ◽  
Michael Gehrke ◽  
Christoph Recknagel ◽  
Dietmar A. Stephan

AbstractBitumen is a crucial building material in road construction, which is exposed to continuously higher stresses due to higher traffic loads and changing climatic conditions. Therefore, various additives are increasingly being added to the bitumen complicating the characterisation of the bituminous binder, especially concerning the reuse of reclaimed asphalt. Therefore, this work aimed to demonstrate that the combination of Fourier transform infrared (FTIR) spectroscopy with attenuated total reflexion (ATR) technique and multivariate evaluation is a very well-suited method to reliable identify and quantify additives in bituminous binders. For this purpose, various unmodified and modified binders, directly and extracted from laboratory and reclaimed asphalts, were investigated with FTIR-ATR spectroscopy. The determined spectra, pre-processed by standard normal variate (SNV) transformation and the determination of the 1st derivation, were evaluated using factor analysis (FA), linear discriminant analysis (LDA) and partial least square regression (PLSR). With this multivariate evaluation, first, a significant model with a very high hit rate of over 90% was developed allowing for the identification of styrene-butadiene copolymers (SBC), ethylene-copolymer bitumen (ECB) and different waxes (e.g. amide and Fischer-Tropsch wax) even if the additives do not show any additional peaks or the samples are multi-modified. Second, a quantification of the content is possible for SBC, ECB, and amide wax with a mean error of RMSE ≤ 0.4 wt% and a coefficient of determination of R2 > 90%. Based on these results, FTIR identification and quantification of additives in bituminous binders is a very promising method with a great potential.


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