Showing 12 results for Antimicrobial
R Abiri, Mb Majnooni, P Malek Khattabi, H Adibi,
Volume 3, Issue 1 (4-2009)
Abstract
Abstract Background and objectives: Infectious diseases are the leading cause of mortality in the world. With the increase of Microbial resistance to chemical antibiotics and low side effects of medicinal herbs, it has become of great importance to use herbs as a source of antimicrobial compounds. Material and Methods: In this study, the extract of Trigonella foenum leaf and seed was prepared using 70% ethanol. Minimum Inhibitory Concentrations (MIC) and antimicrobial Sensitivity were determined using microdilution broth and disk diffusion method, respectively. The Results were compared with Gentamicin, Ciprofloxacin and Fluconasole. The tested strains were: clinical strains of Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Enterococcus faecium, Candida albicans and two standard strains of Staphylococcus aureus and Pseudomonas aeruginosa. Results: The least MIC of the leaf extract against the standard strain of S. S. aureus, E. faecium and clinical S. aureus is 64 μg/ml and for seed extract against E. faecium and Standard S. S. aureus is also 64 μg/ml. The largest diameter of inhibitory zone caused by leaf extract on Standard S. S. aureus is 23mm, and for seed against E. faecium is 18 mm. Conclusion: Because of antimicrobial effects of leaf and seed extract of Trigonella foenum, these extracts can be used as anti microbial compounds in pharmaceutical and food industries. Therefore, the isolation, identification and purification of the antimicrobial compounds of the extracts are recommended. Key words: Trigonella foenum, Antimicrobial effects, Minimum inhibitory concentration.
P Torabi, M Azimirad, Z Hasani, M Janmaleki, H Peirovi, M Alebouyeh, Mr Zali,
Volume 8, Issue 1 (4-2014)
Abstract
Abstract
Background and Objective: This study was aimed to determine the extent of bacterial contamination and drug resistance patterns of isolates colonized in colonoscope and endoscope and in relevant personnel.
Material and Methods: A total of 107 samples were obtained from staff of endoscopy and colonoscopy units (SEU and SCU) and gastroenterological imaging equipment. For isolation and identification of the bacteria, swab culture method and biochemical identification test were used, respectively. Antimicrobial resistance profiles, multi-drug resistance (MDR) patterns and phenetic relatedness of these isolates were also analyzed according to standard methods.
Results: Most frequent pathogenic bacteria among the SEU and gastroenterological imaging related equipments were included S. aureus (20.8 % and 0 %) Enterococcus spp. (0 % and 5.4%) Pseudomonas spp. (0% and 13.5 %), and Clostridium difficile (0% and 12.5%). Analysis of resistance phenotypes showed a high frequency of MDR phenotypes among the SEU (82.1%), and also in endoscopes, colonoscopes, and other equipments (20%, 50% and 100%, respectively). Phylotyping of S. epidermidis isolates showed the role of staff in transmission of resistance strains to medical equipments and also circulation of strains with identical resistance phenotype among the studied samples.
Conclusion: High frequency of pathogenic bacteria in colonoscopes, endoscopes and in the staff of endoscopy & colonoscopy units, and also contamination of these instruments with MDR pathogens emphasize the need for proper disinfection of endoscopes and colonoscopes and also instruction of staff in these units.
Key words: Bacterial Contamination Endoscope Colonoscope Antimicrobial Resistance Gastrointestinal Disease.
L Dolatshah, R Ghanbarpour, F Momeni, H Alizade,
Volume 8, Issue 1 (4-2014)
Abstract
Abstract
Background and Objective: This study was aimed to determine the extent of bacterial contamination and drug resistance patterns of isolates colonized in colonoscope and endoscope and in relevant personnel.
Material and Methods: A total of 107 samples were obtained from staff of endoscopy and colonoscopy units (SEU and SCU) and gastroenterological imaging equipment. For isolation and identification of the bacteria, swab culture method and biochemical identification test were used, respectively. Antimicrobial resistance profiles, multi-drug resistance (MDR) patterns and phenetic relatedness of these isolates were also analyzed according to standard methods.
Results: Most frequent pathogenic bacteria among the SEU and gastroenterological imaging related equipments were included S. aureus (20.8 % and 0 %) Enterococcus spp. (0 % and 5.4%) Pseudomonas spp. (0% and 13.5 %), and Clostridium difficile (0% and 12.5%). Analysis of resistance phenotypes showed a high frequency of MDR phenotypes among the SEU (82.1%), and also in endoscopes, colonoscopes, and other equipments (20%, 50% and 100%, respectively). Phylotyping of S. epidermidis isolates showed the role of staff in transmission of resistance strains to medical equipments and also circulation of strains with identical resistance phenotype among the studied samples.
Conclusion: High frequency of pathogenic bacteria in colonoscopes, endoscopes and in the staff of endoscopy & colonoscopy units, and also contamination of these instruments with MDR pathogens emphasize the need for proper disinfection of endoscopes and colonoscopes and also instruction of staff in these units.
Key words: Bacterial Contamination Endoscope Colonoscope Antimicrobial Resistance Gastrointestinal Disease.
Yaghoobi Avini, M, Daraei, M, Ebrahimipour, Gh,
Volume 8, Issue 5 (1-2015)
Abstract
Abstract Background and Objective: The bacteria living in the specific ecological conditions are among the most promising antimicrobial producers. This study aimed at isolating antimicrobial producing bacteria from soils contaminated with crude oil. Material and Methods: the samples were obtained from crude oil contaminated soils around Dezful located in Khuzestan province, Iran, and antimicrobial producing bacteria were isolated using disc diffusion and cross streak culture. Then, the best bacterium was selected and its antimicrobial potency was studied against indicator microorganisms. The isolate was also characterized based on biochemical properties and phylogenetic analysis. Results: based on the results, the highest antimicrobial activity of isolated bacterium was related to Candida albicans, Aspergillus niger, Bacillus subtilis, E. coli and Klebsiella pneumonia. An intermediate effect was determined against Serratia marcesens and Staphylococcus aureus, whereas no effect was observed against three strains of Enterococcus. Using biochemical characteristics and phenotypic traits, the isolate was identified as Alcaligenes faecalis. Conclusion: given that the isolate has broad spectrum activity against a various range of microorganisms and in comparison with some antimicrobial compounds produced by other Alcaligenes species, it seems the novelty of this antimicrobial compound. Keywords: Antimicrobial Compound, Oil Contaminated Soil, Alcaligenes faecalis
Hesam Alizade , Fatemeh Fallah , Reza Ghanbarpour , Hosein Goudarzi , Hamid Sharifi , Mohammad Reza Aflatoonian ,
Volume 10, Issue 2 (3-2016)
Abstract
ABSTRACT
Background and Objective: One of the main tasks of clinical microbiology laboratories is to determine antibiotic resistance profiles in common pathogens and ensure the selection of effective antibiotics for certain infections. The aim of this study was to compare the methods of disk diffusion, broth microdilution and modified Hodge test in Escherichia coli isolates from urinary tract infection and diarrhea for susceptibility testing against beta-lactam antibiotics in Kerman, Iran.
Methods: In this study, 432 E. coli isolates were collected from diarrhea (216 isolates) and urinary tract infection samples (216 isolates). The antibiotic susceptibility testing methods of disk diffusion, broth microdilution and modified Hodge test were performed according to the Clinical and Laboratory Standards Institute guidelines.
Results: The findings of disk diffusion method showed that resistance to cefotaxime, ceftazidime, aztreonam, cefepime and imipenem was 51.15%, 30.55%, 24.30%, 15.27% and 1.85%, respectively. In the disk diffusion test, 51.15% of the isolates were resistant to at least one antibiotic, all of which were later evaluated by the broth microdilution method. Moreover, 52.94%, 17.19%, 13.12% and 0.90% of the isolates were resistant to cefotaxime, ceftazidime, cefepime and imipenem, respectively. All of the isolates were evaluated for the production of carbapenemase enzyme by the modified Hodge test and none of the isolates were found as positive.
Conclusion: This study shows that performing carbapenem tests is very challenging, and laboratories are recommended to use secondary and independent antibiotic susceptibility tests such as modified Hodge test to confirm the carbapenem-resistant results.
Ali Mohammadi , Maryam Hashemi , Masoud Hosseini ,
Volume 10, Issue 2 (3-2016)
Abstract
Background and Objective: Considering the increasing tendency of public towards green consumption and the dangers of artificial additives, this study aimed to assess antibacterial activity of essential oils of Cinnamomum zeylanicum, Mentha piperita L., Zataria multiflora Boiss and Thymus vulgaris against three important pathogenic and spoilage bacteria (Pseudomonas fluorescens, Erwinia carotovora and Escherichia coli).
- After obtaining the essential oils from Magnolia Co., their antimicrobial activity was assessed using broth microdilution method by determining the minimum inhibitory concentration (MIC50, MIC90) and minimum bactericidal concentration (MBC). All experiments were performed in triplicate and the data were analyzed using the GraphPad software and Duncan's new multiple range test.
- All essential oils showed antimicrobial activity in a concentration-dependent manner. Increasing the concentration of essential oils from 0.01% to 4% (v/v) significantly enhancing the antibacterial activity. The statistical calculations and comparison of data showed that the essential oils of C. zeylanicum and Z. multiflora performed better compared to the other two essential oils, due to having lower values of MIC50 (≤0.1%), MIC90 (≤0.4%) and MBC (≤1%) (P <0.05).
- Considering the high antimicrobial activity of essential oils of C. zeylanicum and Z. multiflora, they can be used as effective food additives with fewer side effects. However, further studies are being conducted on the effectiveness of essential oils on the growth of other microorganisms and their results will be published soon.
- Essential Oils, Antimicrobial, Pathogenic Bacteria, Cinnamomum Zeylanicum, Zataria Multiflora Boiss.
Jila Asghari , Sanaz Sadani , Ezzatollah Ghaemi , Mohsen Mazaheri Tehrani ,
Volume 10, Issue 3 (5-2016)
Abstract
ABSTRACT
Background and Objective: Lavandula stoechas is a species of native and permanent plants in Golestan province that belongs to the family Lamiaceae. L. stoechas has been used in traditional medicine for treatment of various diseases. The aim of this study was to extract essential oil using steam distillation method from the flowers of L. stoechas collected from Jahan-nama region in the Golestan province, and evaluate its antibacterial activity.
Methods: Steam distillation (Clevenger) and GC-MS system were used to separate volatile oils and identify the essential oil components, respectively. Two methods of disk diffusion and broth micro dilution were used to evaluate the antimicrobial effect of L. stoechas essential oil. Six bacterial species including Staphylococcus aureus, Bacillus sp., Enterococcus faecalis, Salmonella enteritidis, Escherichia coli and Pseudomonas aeruginosa were tested.
Results: The essential oil yield was 0.28%. The main components were camphor (71.86%), 1, 8-cineole (4.08%), linalool (3.77%) and borneol (3.19%). The essential oil showed no inhibitory effect on P. aeruginosa and E. faecalis, while it had different inhibitory effects on other bacteria. S. aureus and Bacillus sp. showed the highest sensitivity with inhibition zone diameter of 32 and 29 mm, respectively.
Conclusion: The results of this study showed that the essential oil of L. stoechas has high inhibitory and antimicrobial activity particularly against Gram-positive bacteria, which may be due to the presence of 71.86% camphor in its composition.
Masoumeh Mazandarani, Leili Monfaredi ,
Volume 11, Issue 1 (1-2017)
Abstract
ABSTRACT
Background and Objectives: Many aromatic plants from the genus Satureja have been used in traditional medicine in north of Iran. This study aimed to determine the ecological requirements for the growth of Satureja mutica Fisch. & C.A. Mey, and evaluate antioxidant and antibacterial activity of ethanolic extract of S. mutica collected from North Khorasan Province, Iran.
Methods: Aerial parts of S. mutica were collected in blooming stage. Ecological requirements and the traditional uses of the plant were recorded. Ethanol extract of the plant was prepared by maceration. Antioxidant capacity of the extract was measured by three methods of total antioxidant capacity, reducing power and 2,2-Diphenyl-1-picrylhydrazyl, and then compared with standard antioxidants (butylated hydroxyanisole and butylated hydroxytoluene). Antibacterial activity of the extract was studied against nine Gram-positive and Gram-negative bacteria by agar dilution method and determining the minimum inhibitory concentrations (MICs).
Results: S. mutica is the most common wild aromatic annual herb in north slob and sunny areas around mountains of Bojnord (1020-1300 m). The ecological features of this region are as follows: annual rainfall 308 mm, average temperature 11.5 oC, semi dry cold climate in the sandy clay loam soil, Ec=0.7 desizimence, and pH= 7.30. Ethnopharmacological data showed that this plant has been widely used by rural people as an anti-infective, antispasm and sedative agent that could treat rheumatic pain, migraine, toothache and diarrhea. The ethanol extract of S.mutica had relatively high antioxidant activity with IC50 value of 11.2 mg/ml. The extract also had high antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus and Enterococcus faecalis, with inhibition zone diameters ranging between 15.1±0.5 and 27.7±0.8 mm and MIC values of 60, 68, 53 and 83 mg/ml, respectively.
Conclusion: It can be concluded that the extract of S. mutica has favorable antibacterial and antioxidant activity, which could be used as natural anti-microbial agent for treatment of some infection diseases.
Keywords: Antioxidant, Antimicrobial, Bojnord, Ecological Requirements, North Khorasan, BHT, BHA.
Mohammad Bokaeian, Shahram Shahraki Zahedani , Abbasali Delarampoor, Mohammadreza Atashgah, Bahram Dahmarde ,
Volume 12, Issue 3 (5-2018)
Abstract
ABSTRACT
Background and Objectives: The resistance of gram-negative bacteria to antibiotics has become a serious problem, which imposes a significant increase in treatment costs. Klebsiella pneumoniae is an important nosocomial pathogen from the Enterobacteriaceae family. The aim of this study was to investigate the frequency and pattern of antibiotic resistance in K. pneumoniae strains isolated from clinical samples.
Methods: This descriptive, cross-sectional study was performed on 150 K. pneumonia strains isolated from different clinical samples such as urine, sputum, blood, ulcers, lung secretions and abdominal abscess. Antibiogram test was performed using the disk diffusion method (Kirby-Bauer). Minimum inhibitory concentration of amikacin, tobramycin and gentamicin was determined via the E-test for 50 strains with high resistance rates.
Results: In this study, the highest rate of resistance was observed against carbenicilin, ceftriaxone, cefepime and streptomycin. K. pneumonia isolates were most frequent in urine and sputum samples. In the E-test, the highest rate of resistance was observed against gentamicin, tobramycin (16µg/ml) and amikacin (64µg/ml).
Conclusion: Based on our results, tigecycline, netilmicin, kanamycin and amikacin are the most effective antibiotics for the treatment of K. pneumoniae infections.
Keywords: Klebsiella pneumoniae, antimicrobial resistance, E-test method
Maryam Kouhkan, Miri Mahmoody, Jabbar Khalafy, Sima Pourali, Nasser Samadi,
Volume 14, Issue 2 (3-2020)
Abstract
ABSTRACT
Background and objectives: Antimicrobial resistance is a serious threat to global public health. The overuse and misuse of antibiotics are the most important contributing factors to development of antibiotic resistance. Thus, there is an urgent need to identify and discover new compounds against drug-resistant microorganisms. We have previously synthesized new series of 3-substituted 5H-(1,2,4)triazolo(3',4':2,3) (1,3,4)thiadiazino(5,6-b)quinoxaline derivatives (4a-4f). Here, we evaluate the antimicrobial activity of these derivatives against methicillin-resistant
Staphylococcus aureus, S. aureus, Streptococcus pyogenes,
Pseudomonas aeruginosa,
Escherichia coli,
Candida albicans, Candida tropicalis and
Candida krusei.
Methods: The agar well diffusion and agar dilution methods were used for determining inhibition zone diameter and minimum inhibitory concentration during preliminary evaluation of antimicrobial activity.
Results: All synthesized compounds exhibited antibacterial and antifungal activity against the tested microorganisms
.
Conclusion: Our findings indicate the antimicrobial potential of the six novel synthetic triazolo thiadiazin quinoxaline compounds.
Keywords: Antimicrobial,
Anti-bacterial agents,
Antifungal agents, Triazolo, Thiadiazin, Quinoxaline.
Abolfazl Shirdel Abdolmaleki, Abolfazl Rafati Zomorodi, Mohammad Motamedifar, Yalda Malekzadegan,
Volume 18, Issue 1 (1-2024)
Abstract
Background: Urinary tract infection (UTI) is one of the most common bacterial infections of all ages and sexes. Escherichia coli is reported as the most common predominant pathogen. Urinary tract infection treatment leads to abundant antibiotic application in hospitals and communities, continuously developing multidrug resistance (MDR). This study aimed to determine the sensitivity and resistance pattern to common antibiotics among E. coli isolates from patients with UTIs at Nemazee Hospital in Shiraz.
Methods: This retrospective cross-sectional survey studied 1910 positive urine samples with E. coli bacteria from patients referred to Nemazee Hospital from 2018 to 2019. Antimicrobial susceptibility testing was performed on 12 commonly used antibiotics for UTIs.
Results: A total of 1910 E. coli isolates were gathered during these 2 years. The most highlighted resistance was observed against quinolones and cephalosporins at 86.9% and 89.7%, respectively. Cephalexin (87.9%) and nalidixic acid (86.1%) have shown the lowest activity against E. coli isolates. Also, the highest susceptibility was determined for amikacin (88.3%), nitrofurantoin (76.8%), and gentamicin (70.6%). In addition, 1624 (85%) isolates were MDR.
Conclusion: In conclusion, resistance to antibiotics (such as ciprofloxacin, norfloxacin, tetracycline, cefotaxime, and nitrofurantoin) is increasing. Therefore, it is vital to follow an appropriate antimicrobial stewardship program.
Sujata Lall, Vivek Bhat, Sanjay Biswas, Navin Khattry,
Volume 18, Issue 4 (7-2024)
Abstract
Background and Objectives: Tigecycline susceptibility testing and reporting remains enigmatousdue to lack of established guidelines.Disc diffusion as a method of performing susceptibility remains more widely accepted worldwide due to its ease of performance. Not much published literature is available from India on the utility of this method, especially from a cancer care setting; hence the study was conducted to find out the performance characteristics of disc diffusion by comparing its results with VITEK-2 COMPACT considering results of the later as standard.
Methods: Disc diffusion was performed by Kirby Bauer’s method using Mueller -Hinton agar and Hi-media 15mcg TGC disc using FDA and EUCAST breakpoints. When categorical agreement is ≥ 90%, Very Major Error is ≤ 1.5%, and Major Error ≤ 3%, the disc diffusion breakpoints can be considered acceptable according to CLSI criteria.
Results:By using Cohen’s kappa coefficient, kappa was 0.328 with a p value of <0.05. The agreement percentage noted was 60.84%. Two strains reported as resistant by VITEK-2 COMPACT were misclassified as sensitive by disc diffusion, hence 0.76% of very major error was noted.9.5% of major error and 27.7% of minor error was noted as 25 of susceptible reported strains were identified as resistant.
Conclusion:Since poor agreement was observed and it exceeded the acceptable performance rate, hence the disc diffusion method was not acceptable according to the CLSIcriteria. There is gap in uniformity and lack of streamlined harmonized TST which might become an alarming cause of concern.
