Microbiology
Shima Firozi Rad; Reza Habibipour; Leila Moradi Haghgou
Volume 28, Issue 4 , September and October 2021, , Pages 489-501
Abstract
Introduction: Candida albicans is the most common fungus pathogen in terms of biofilm colonization and formation. Considering that the biofilm-producing Candida species show less sensitivity to anti-fungus medicines, hence the treatment should be accomplished through other anti-fungus factors with high ...
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Introduction: Candida albicans is the most common fungus pathogen in terms of biofilm colonization and formation. Considering that the biofilm-producing Candida species show less sensitivity to anti-fungus medicines, hence the treatment should be accomplished through other anti-fungus factors with high effect and low cytotoxicity. In parallel with this, the present study investigated the C. albicans biofilm formation in the presence of Graphene Dioxide and Reduced Graphene Oxide Nano-sheets. Materials and Methods: Graphene Dioxide and Reduced Graphene Oxide Nano-sheets synthesis were done through the Hummer Method using natural graphite. After 24 hours of incubating of C. albicans with different concentrations of 0, 20, 40, 60, 80, 100 ppm of Nano-sheets, biofilm formation was investigated through the ELISA method, and results were analyzed by SPSS ver.18 software (p <0.01). Results: Graphene Oxide Nano-sheets was more effective to control C. albicans biofilm compared to Reduced Graphene Oxide (p < 0.01). The most effective concentration in biofilm formation was 100 ppm and the best time was 48 and 24 hours for Graphene Oxide and Reduced Graphene Oxide respectively (p < 0.01). Conclusion: According to the obtained results, Graphene Oxide Nano-sheets and Reduced Graphene Oxide can be proposed for further investigations to control Candida albicans.
Microbiology
Elaheh Tasallot Maraghi; Nasim Kashef; Ahmad Reza Gohari; Zahra Fekrirad
Volume 28, Issue 4 , September and October 2021, , Pages 556-568
Abstract
Introduction: Staphylococcus aureus is one of the most important pathogenic bacteria in humans. Due to the antibiotic resistance, treatment of staphylococcal infections is difficult. Among the alternative treatment options, plants are considered as a rich source of material with antimicrobial activity. ...
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Introduction: Staphylococcus aureus is one of the most important pathogenic bacteria in humans. Due to the antibiotic resistance, treatment of staphylococcal infections is difficult. Among the alternative treatment options, plants are considered as a rich source of material with antimicrobial activity. The aim of this study was to evaluate of the antimicrobial effects of ethyl acetatic, methanolic and water-methanolic extracts from Satureja khuzistanica, Peganum harmala, Satureja sahendica onplanktonic growth and biofilm formation of S. aureus.
Materials and Methods: The extracts were prepared from different parts of plants and the antimicrobial properties of the extracts were determined by disk diffusion and microbroth dilution method. Also, Crystal violet staining assay was used to evaluate the ability to inhibit biofilm formation of S. aureus strains. Disruption of pre-formed biofilms of S. aureus strains were evaluated following exposure to plant extracts in different concentrations (ranging from 3/125 to 400mg/ml).
Results: The highest inhibitory zones were showed by ethyl acetatic extract of Satureja sahendica (28/6±0.6mm). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ethyl acetatic extract of S.khuzistanica were 1/562 and 3/125mg/ml, respectively. Besides, methanolic extract of S. khuzistanica was the most effective extract in inhibition of microbial cells attachment to surface (57/89%) and it showed disruption of pre-formed biofilms at the concentration of 50 mg/ml.
Conclusion: The extracts of all mentioned plants had satisfactory antimicrobial effects against the planktonic growth of S. aureus and methanolic extract of S. khuzistanica was effective against biofilm formation of S. aureus.
Ziba Foladvand; Zohreh Kiani; Fereshteh Javadian; Mehran Hesaraki; Aliakbar Nasiri; Zahra Sepehri
Volume 21, Issue 6 , January and February 2015, , Pages 1019-1027
Abstract
Background and Purpose: Development of antibiotic resistance among pathogenic bacteria motivates attempts to search for newer antimicrobial agents. In this research study, antibacterial effect of plant extract of M. communis , z.multiflora and Allium sativum on biofilm formation by strains of Staphylococcus ...
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Background and Purpose: Development of antibiotic resistance among pathogenic bacteria motivates attempts to search for newer antimicrobial agents. In this research study, antibacterial effect of plant extract of M. communis , z.multiflora and Allium sativum on biofilm formation by strains of Staphylococcus aureus resistant to the antibiotic were investigated.
Methods and Materials: 17 samples were separated from nose and throat of hospital and non-hospital personnels. The effect of extracts on biofilm formation by S.aureus and its resistant respect to the antibiotic were determined using a microplate 96 .
Results: Effect of antibacterial extracts used at different concentrations showed that, despite the relative resistance of most strains at concentrations used, the maximum sensitivity was at concentrations of 1.25, 2.5 and 5 mg/ml of extracts and concentration of 10 mg/ml of the extract was considered as MBC. Bacterial growth was observed only at 24 hours and no biofilm was observed at any of the extracts.
Conclusion : Results showed that plant extracts can reduce biofilm formation by Staphylococcus aureus and, therefore, they can play an important role in reducing disease.