Showing 24 results for Microbial
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.
M Raeisi, H Tajik, J Aliakbarlu,
Volume 6, Issue 2 (10-2012)
Abstract
Abstract
Background and objectives: The presence of pathogenic bacteria and the factors causing food spoilage are the great challenge for public health. Attention to natural additives instead of chemical preservatives resulted in conducting several studies on plant essential oil and extracts. We aimed at evaluating the antibacterial effect of carboxymethyl cellulose coating enriched by Zataria multiflora essential oil and grape seed extract on rainbow trout meat.
Material and methods: In this study, two concentrations of Zataria multiflora essential oil (1% and 2%) and two concentrations of grape seed extract (0.5% and 1%) were used both alone and in combination with Carboxymethyl cellulose coating. Antibacterial effect of these treatments was evaluated by enumeration of bacteria in special culture media.
Results: The results obtained in this study demonstrate that Zataria multiflora essential oil in combination with grape seed extract significantly can decrease the number of bacteria and delay the spoilage of the samples (p<0.05).
Conclusion: Coating enriched by Zataria multiflora and grape seed extract can properly delay the growth of spoilage microorganisms and prolong the shelf life of meat products.
Key words: Carboxymethyl cellulose coating, Zataria multiflora essential oil, Grape seed extract, Microbial flora
M Naderinasab, N Tayyebi Meibodi, Y Nahidi, A Bakhshizadeh,
Volume 7, Issue 3 (10-2013)
Abstract
Abstract
Background and Objective: Cross-transmission of microorganisms by the hands of health care workers is considered as a main transmission route of nosocomial infections. The aim of this study was to investigate the microbial contamination of health-care worker’s hands while going out of hospital.
Material and Methods: Wearing the sterile glove with liquid culture, we obtained 100 Samples from the staff’s hands of three departments (clerical department, emergency ward and central laboratory) of Emam Reza hospital. After that, the samples were cultured.
Results: Of all personnel, 40% have the habit of washing their hands. Of these, 95 percent wash their hands with water and soap, and 5 percent with alcohol rubs. Of 100 cultured samples, 90 have microorganisms including non-pathogen gram-positive bacillus (29%), coagulase-positive staphylococcus (39%), coagulase-negative staphylococcus (47%), Enterococci (3%), micrococcus (25%) and candida (3%). Contamination in those who had not washed their hands is 62.6% and in those who washed is 37.7% (P=0.04).
Conclusion: Hands of health-care workers become progressively contaminated by the potential pathogens during daily activities. To reduce the rate of contamination, it is helpful if we ask staff to wash their hands while going out of hospital.
Keywords: Microbial Flora Hospital’s Staff Hand Washing
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.
M Keshtvarz, Mh Pourmand, Shirazi, M Yousefi, S Hajikhani,
Volume 8, Issue 1 (4-2014)
Abstract
Abstract
Background and Objective: Transmission of pathogens by cosmetics is one of the major health complications. Direct contact with contaminated non-standard cosmetics can have irreparable side effects for the consumers. Thus, the evaluation of microbial contamination in cosmetic products is important. The aim of this study was to assess the microbiological contamination of one of frequently used cream.
Material and Methods: In the present study, 135 samples of a special moisturizing cream were randomly selected from pharmacies in Tehran. The microbial contamination assessment, sampling and culturing method were based on the protocol (No.3978) of Iranian Institute of Standard and Industrial Research.
Results: sixty-two (46%) out of 135 samples were contaminated. The highest and lowest contaminations observed were Pseudomonas aeruginosa and Bacillus, respectively.
Conclusion: Due to the high contamination rate of cosmetic creams, we recommend extremely monitoring and controlling these products by health centers.
Keywords: Cosmetics, Microbial Contamination, Pseudomonas Aeruginosa
M Rezaei, R Ghasemi Khah, M Parviz, O Zarei,
Volume 8, Issue 2 (7-2014)
Abstract
Abstract Background and Objective: Ice cream is a suitable environment for microbial growth due to its chemical structure, ingredients, and its increased supply and demand. In the absence of hygienic considerations, it can cause poisoning. This study aimed to determine bacterial contamination in traditional ice cream produced in Arak city in 2011. Material and Methods: The samples (n= 30) were randomly obtained from different parts of Arak in, 2011. The Samples were shipped in cold conditions and total count of microorganisms test was performed according to Iranian national standards. Results: In 16.66%, the microbial contamination was below the limit of microbial load (5×104), and in 83.3% the contamination was more than allowed level. Conclusion: This study highlights the dire situation for bacterial contamination of traditional ice cream in Arak city. Keywords: Arak, Ice Cream, Microbial Contamination
M Azimi, Sh Moghadam, L Jouybari, N Bahnampour, Ea Ghaemi, M Hesam, M Bazori, A Sanagoo,
Volume 8, Issue 2 (7-2014)
Abstract
Abstract
Background and Objective: Bacterial colonization in upper respiratory airways is one of the major risk factors for the development of the ventilator–associated pneumonia (VAP), which is the most common and serious hospital-acquired infection in intensive care unit (ICU). The aim of this study was to determine the frequency of oropharyngeal microorganisms of patients with tracheal tube hospitalized in ICU.
Material and Methods: Of 39 patients hospitalized in ICU of panje Azar Hospital, the oropharyngeal cultures were taken after admission. The samples were evaluated for growth of Staphylococcus aureus, Pneumococcus, Enterococcus, Pseudomonas, and E-coli.
Results: The mean age of the patients (21 men, 18 women) was 43.64±15.01. The culture was positive in 28.2% and the most common isolate was Pseudomonas aeruginosa (10.3%).
Conclusion: Pseudomonas, which is the main pathogen for ventilator- associated pneumonia, may be a potential threat for the patients hospitalized in intensive care units.
Keywords: Microbial Colonization, Endotracheal Tube, Intensive Care Unit, Ventilator Associated Pneumonia
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
Manshouri, M, Yazdanbakhsh, Ar, Bay, A, Sadeghi, M, Tazikeh, F, Elyasi, Sa, Paydar, R,
Volume 9, Issue 3 (9-2015)
Abstract
Abstract
Background and Objective: Swimming pools, which are recreational places, can cause transmission of bacterial diseases, fungal and parasitic infections due to direct contact with various groups of people. We aimed to determine and compare the common microbial indicators in the water of pools and Jacuzzis in Golestan province.
Material and Methods: the samples were obtained from eight indoor pool and Jacuzzi in Golestan province from July to December 2010, to evaluate the biological and physiochemical parameters.
Results: The residual chlorine in the pool and Jacuzzis was 74.3 % and the 41.1 %, respectively, and the difference was significant; the pH level was 70.4 % and 78.1 %, respectively; the mean of turbidity was 17.8 %, and 9.8 % and the difference was not significant. The samples contaminated with total coliform in the pool and Jacuzzi, respectively, were 4.3 % and 15.2 % and with E. coli were 1.3 % and 11.2 %.
Conclusions: The higher contamination of Jacuzzi is related to the higher temperature and turbidity of water, and more exposure of swimmer with water and less recirculation of Jacuzzi water. The high turbidity, lack of desired residual chlorine and choliform contamination are the main problems of swimming pools and Jacuzzi in Golestan province.
Keywords: Biological indicators, Microbial, Pool, Golestan Province.
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.
Reza Habibipour, Gholamreza Zarrini, Shohreh Yarizadeh,
Volume 11, Issue 3 (5-2017)
Abstract
ABSTRACT
Background and Objective: Nanobacteria are nanometer-scale particles with different shapes, which have been a subject of debate in modern microbiology. They belong to a proposed class of living organisms, specifically cell-walled microorganisms with a size much smaller than the generally accepted lower limit for life. Since some microorganisms are able to continue growth at high temperatures, we aimed to isolate thermophilic bacteria from Gheinarcheh hot spring in Ardabil (Iran) and identify the characteristics of these microorganisms.
Methods: Microbial mats were found in cultures from Gheinarcheh hot spring in North West of Iran. Synthetic media were prepared and used for isolation of protease-producing thermophilic bacteria, and identification of the features of microbial mats. Cultures were incubated at temperature range of 60-120 oC. Scanning electron microscopy, DNA extraction and polymerase chain reaction were used to further identify characteristics of the microbial biofilms.
Results: Microbial biofilms of nanoparticles were detected in our samples. Growth of the bacteria increased at all temperatures tested. Results of scanning electron microscopy showed nano-sized particles in the scale of 60 nm. No band was visible in gel electrophoresis of polymerase chain reaction products.
Conclusion: This study is the first to report the presence of hyperthermophilic nanobacteria in Iran.
Keywords: Nanobacteria, Hyperthermophile, Microbial Mat.
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.
Mojtaba Chizari, Seyed Masoud Hosseini, Ali Mohammadi, Javad Fakhari, Mojtaba Mashhadi Mohammadzadeh-Vazifeh,
Volume 14, Issue 6 (11-2020)
Abstract
Background and objectives: Dried Black Curd (DBC), also known as Gharahghorut (Persian), is a dairy product produced from curd of yogurt or doogh. The aim of this study was to evaluate microbial contamination of industrially and traditionally produced DBC in Iran.
Methods: Four DBC brands holding certification of the Institute of Standards and Industrial Research of Iran (ISIRI), Iran Ministry of Health and Medical Education (IMHME) and ISO were purchased from a market in Tehran, Iran. Microbial monitoring for presence of coliform, Escherichia coli, coagulase-positive Staphylococcus aureus, mold and yeast was performed using different basic, enriched, selective and differential media including peptone water agar, MacCankey agar, blood agar and brain heart infusion agar, etc. according to the ISIRI standards (No.13299).
Results: None of the tested samples had microbial contamination. However, in one traditional DBC sample, the population of mold and yeast was higher than the acceptable level defined by the ISIRI standard.
Conclusion: We found no contamination with coagulase-positive S. aureus, E. coli and coliforms in four brands of traditionally and industrially produced DBC in Iran. This indicates that the hygienic practices designated by the IMHME are well-implemented in the industrial sector. However, the mold and yeast contamination in traditionally produced DBC should be prevented by applying hygienic practices during the process of manufacturing and distribution.
Maryam Rafiee, Alijan Tabarraei, Mahsa Yazdi, Alireza Mohebbi, Ezzat Allah Ghaemi,
Volume 17, Issue 2 (3-2023)
Abstract
Background and objectives: Urinary tract infection (UTI) is one of the most common bacterial infections. Staphylococcus saprophyticus is a common Gram-positive bacterium that causes uncomplicated UTIs in women. The present study aimed to study the drug resistance pattern and phenotypic and genotypic variation of S. saprophyticus isolates from women with UTI in Gorgan, northern Iran.
Methods: This study was performed from May 2018 to September 2020. During this time, 35 S. saprophyticus strains were isolated from patients with UTI. The antimicrobial patterns of the isolates were determined by a conventional method. Phenotypic criteria such as pigment production, mannitol fermentation, urease production, and 16SrRNA gene valuation were studied.
Results: All isolates were sensitive to nitrofurantoin, gentamicin, and linezolid. S. saprophyticus isolates showed the highest level of resistance to penicillin (85.7%) and erythromycin (51.4%). A variation was detected among S. saprophyticus isolates in terms of pigment production i.e. about 51.4% showed yellow pigment in Muller Hinton agar, and 62.9% of the isolates were able to ferment mannitol sugar. Of 11 isolates that were sequenced for the 16SrRNA gene, only two isolates showed different patterns.
Conclusion: Nitrofurantoin and trimethoprim-sulfamethoxazole are the antibiotics of choice for the treatment of UTI caused by S. saprophyticus in the study area. Due to the phenotypic and genotypic differences among S. saprophyticus isolates, typing of S. saprophyticus at the subspecies level is recommended.
Sadaf Khursheed Baba, Abiroo Jan, Mohd Suhail Lone, Dalip K Kakru, Bashir Ahmad Fomda, Gulnaz Bashir, Nadeem Ahmad Bhat,
Volume 17, Issue 3 (5-2023)
Abstract
Background and objectives: Conventional culture and sensitivity methods take around 48 hours to generate antibiotic sensitivity results after a blood culture is flagged as positive by automated systems. However, it is imperative to initiate early targeted antibiotic therapy for effective management of sepsis and to reduce morbidity, mortality, and cost of treatment. This study aimed to evaluate the direct sensitivity test (DST) as a potential tool to obtain quicker antibiotic susceptibility results from positive BacT/ALERT blood culture vials and the VITEK-2 system (the reference method).
Methods: Blood culture bottles flagged as positive by BacT/ALERT were Gram-stained. Cultures with polymicrobial growth were excluded from the study. The isolates were then simultaneously cultured and processed for the DST using the disk diffusion method. Agreements or errors were interpreted according to the Clinical and Laboratory Standards Institute’s guidelines.
Results: Among 76 Gram-positive isolates, we observed 99.2% essential agreement between the DST and AST. The rate of minor and major errors was 4.04% and 1.18%, respectively. Among 75 Gram-negative isolates, we observed 98.99% essential agreement between the DST and AST. The rate of minor and major errors was 4% and 2%, respectively. No very major error was seen in either Gram-negative or -positive isolates.
Conclusions: The DST results are available earlier than the AST results, which can ultimately help in the early initiation of targeted antibiotic therapy.
