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Tabata T, Nakagawa H, Matin K, Otsuki M, Aoki A, Sumi Y, Shimada Y. Analysis of cariogenic biofilms by using a swept-source optical coherence tomography in vitro. Arch Oral Biol 2024; 165:106009. [PMID: 38838513 DOI: 10.1016/j.archoralbio.2024.106009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 05/18/2024] [Accepted: 05/21/2024] [Indexed: 06/07/2024]
Abstract
OBJECTIVE The objective was to measure the thickness of Streptococcus mutans (S. mutans) biofilms forming in an oral biofilm reactor (OBR) by using a noninvasive swept-source optical coherence tomography (SS-OCT) system at every 4 h time interval until 20 h and analyze the correlations with the amounts of biofilms. METHODS S. mutans biofilms were formed on square-shaped bovine enamel blocks inside an OBR. Biofilms were analyzed at every 4 h stage (4 h, 8 h, 12 h, 16 h and 20 h) using a SS-OCT system and a laser scanning confocal microscope (LSCM). The amounts of biofilms were measured at each stage by separating the water insoluble glucan (WIG) and bacterial cells. Co-relationships between the SS-OCT measured biofilm thickness and the amounts of adhered biofilms were analyzed. RESULTS The thickness of biofilms detected on SS-OCT images at 4 h stage was 0.059 ± 0.029 (Av ± SD) mm which increased time-dependently in a linear fashion after 8 h stage and reached to 0.435 ± 0.159 mm at 20 h stage and the correlation coefficient was about 0.89. The amounts of biofilms; bacterial optical density (OD) and WIG concentration increased time-dependently were 0.035 ± 0.008 / mm2 and 10.328 ± 2.492 µg/ mm2 respectively at 20 h stage. Correlation coefficients of 0.66 between 'the amounts of bacteria' and 'biofilm thickness on OCT' and 0.67 between 'the amounts of WIG' and 'biofilm thickness on OCT' were obtained, suggesting that there was a relatively positive correlation between them. CONCLUSION The SS-OCT can be a useful tool to measure time-dependent growth of biofilms. Further studies are needed in order to assess biofilms using SS-OCT more accurately.
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Affiliation(s)
- Tomoko Tabata
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Hisaichi Nakagawa
- Department of Oral Biomedical Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan
| | - Khairul Matin
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan; Department of Oral Medicine and Stomatology, School of Dental Medicine, Tsurumi University, Japan; Medoc International Co. Ltd., Tokyo, Japan.
| | - Masayuki Otsuki
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Akira Aoki
- Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yasunori Sumi
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Yasushi Shimada
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
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Pignet AL, Schellnegger M, Hecker A, Kamolz LP, Kotzbeck P. Modeling Wound Chronicity In Vivo: The Translational Challenge to Capture the Complexity of Chronic Wounds. J Invest Dermatol 2024; 144:1454-1470. [PMID: 38483357 DOI: 10.1016/j.jid.2023.11.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 11/14/2023] [Accepted: 11/19/2023] [Indexed: 06/24/2024]
Abstract
In an aging society with common lifestyle-associated health issues such as obesity and diabetes, chronic wounds pose a frequent challenge that physicians face in everyday clinical practice. Therefore, nonhealing wounds have attracted much scientific attention. Several in vitro and in vivo models have been introduced to deepen our understanding of chronic wound pathogenesis and amplify therapeutic strategies. Understanding how wounds become chronic will provide insights to reverse or avoid chronicity. Although choosing a suitable model is of utmost importance to receive valuable outcomes, an ideal in vivo model capturing the complexity of chronic wounds is still missing and remains a translational challenge. This review discusses the most relevant mammalian models for wound healing studies and provides guidance on how to implement the hallmarks of chronic wounds. It highlights the benefits and pitfalls of established models and maps out future avenues for research.
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Affiliation(s)
- Anna-Lisa Pignet
- Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Medical University of Graz, Graz, Austria; COREMED - Centre for Regenerative and Precision Medicine, JOANNEUM RESEARCH, Graz, Austria; Research Unit for Tissue Repair and Reconstruction, Medical University of Graz, Graz, Austria
| | - Marlies Schellnegger
- Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Medical University of Graz, Graz, Austria; COREMED - Centre for Regenerative and Precision Medicine, JOANNEUM RESEARCH, Graz, Austria; Research Unit for Tissue Repair and Reconstruction, Medical University of Graz, Graz, Austria.
| | - Andrzej Hecker
- Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Medical University of Graz, Graz, Austria; COREMED - Centre for Regenerative and Precision Medicine, JOANNEUM RESEARCH, Graz, Austria; Research Unit for Tissue Repair and Reconstruction, Medical University of Graz, Graz, Austria
| | - Lars-Peter Kamolz
- Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Medical University of Graz, Graz, Austria; COREMED - Centre for Regenerative and Precision Medicine, JOANNEUM RESEARCH, Graz, Austria
| | - Petra Kotzbeck
- Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Medical University of Graz, Graz, Austria; COREMED - Centre for Regenerative and Precision Medicine, JOANNEUM RESEARCH, Graz, Austria; Research Unit for Tissue Repair and Reconstruction, Medical University of Graz, Graz, Austria
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Li P, Zhang Y, Chen D, Lin H. Investigation of a novel biofilm model close to the original oral microbiome. Appl Microbiol Biotechnol 2024; 108:330. [PMID: 38730049 PMCID: PMC11087337 DOI: 10.1007/s00253-024-13149-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 01/13/2024] [Accepted: 04/16/2024] [Indexed: 05/12/2024]
Abstract
A more optimized culture medium used in vitro to mimic the bacterial composition of original oral flora as similar as possible remains difficult at present, and the goal of this study is to develop a novel oral biofilm medium to restore the original oral microbiome. Firstly, we conducted a systematic literature review by searching PubMed and summarized the current reported culture media in vitro. Seven culture media were found. We used mixed saliva as the origin of oral species to compare the effects of the above media in culturing oral multispecies biofilms. Results indicated that among the seven media brain heart infusion containing 1% sucrose (BHIs) medium, PG medium, artificial saliva (AS) medium, and SHI medium could obviously gain large oral biofilm in vitro. The nutrients contained in different culture media may be suitable for the growth of different oral bacteria; therefore, we optimized several novel media accordingly. Notably, results of crystal violet staining showed that the biofilm cultured in our modified artificial saliva (MAS) medium had the highest amount of biofilm biomass. 16S rRNA gene sequencing showed that the operational taxonomic units (OTUs) and Shannon index of biofilm cultured in MAS medium were also the highest among all the tested media. More importantly, the 16S rRNA gene sequencing analysis indicated that the biofilm cultured in MAS medium was closer to the original saliva species. Besides, biofilm cultured by MAS was denser and produced more exopolysaccharides. MAS supported stable biofilm formation on different substrata. In conclusion, this study demonstrated a novel MAS medium that could culture oral biofilm in vitro closer to the original oral microbiome, showing a good application prospect. KEY POINTS: • We compare the effects of different media in culturing oral biofilms • A novel modified artificial saliva (MAS) medium was obtained in our study • The MAS medium could culture biofilm that was closer to oral microbiome.
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Affiliation(s)
- Pengpeng Li
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, Guangdong, China
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Yuwen Zhang
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, Guangdong, China
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Dongru Chen
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, Guangdong, China.
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China.
| | - Huancai Lin
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, Guangdong, China.
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China.
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Sentkowska A, Konarska J, Szmytke J, Grudniak A. Herbal Polyphenols as Selenium Reducers in the Green Synthesis of Selenium Nanoparticles: Antibacterial and Antioxidant Capabilities of the Obtained SeNPs. Molecules 2024; 29:1686. [PMID: 38675506 PMCID: PMC11052002 DOI: 10.3390/molecules29081686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/05/2024] [Accepted: 04/06/2024] [Indexed: 04/28/2024] Open
Abstract
Selenium is an essential trace element for the proper functioning of the human body. In recent years, great attention has been paid to selenium nanoparticles (SeNPs) due to their potential for medicinal applications. In this study, herbal extracts were used in the green synthesis of SeNPs. The influence of herbal species, the ratio of the reagents, and post-reaction heating on the antibacterial and antioxidant properties of obtained SeNPs were investigated. The relationship between these properties and the physical parameters of obtained nanoparticles (e.g., size, shape) was also studied. It has been proven that SeNPs showed higher antioxidant and antibacterial properties in comparison to herbal extracts taken for their synthesis. Heating of the post-reaction mixture did not affect the SeNP size, shape, or other studied properties.
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Affiliation(s)
| | - Julia Konarska
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland (J.S.); (A.G.)
| | - Jakub Szmytke
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland (J.S.); (A.G.)
| | - Anna Grudniak
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland (J.S.); (A.G.)
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Li SX, Gao XR, Yi J, Jia LY, Ren J. A new strategy of using periphyton to simultaneously promote remediation of PAHs-contaminated soil and production of safer crops. ENVIRONMENTAL RESEARCH 2024; 246:118149. [PMID: 38199466 DOI: 10.1016/j.envres.2024.118149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/20/2023] [Accepted: 01/05/2024] [Indexed: 01/12/2024]
Abstract
Contaminated farmland leads to serious problems for human health through biomagnification in the soil-crop-human chain. In this paper, we have established a new soil remediation strategy using periphyton for the production of safer rice. Four representative polycyclic aromatic hydrocarbons (PAHs), including phenanthrene (Phe), pyrene (Pyr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP), were chosen to generate artificially contaminated soil. Pot experiments demonstrated that in comparison with rice cultivation in polluted soil with ΣPAHs (50 mg kg-1) but without periphyton, adding periphyton decreased ΣPAHs contents in both rice roots and shoots by 98.98% and 99.76%, respectively, and soil ΣPAHs removal reached 94.19%. Subsequently, risk assessment of ΣPAHs based on toxic equivalent concentration (TEQ), pollution load index (PLI), hazard index (HI), toxic unit for PAHs mixture (TUm), and incremental lifetime cancer risk (ILCR) indicated that periphyton lowered the ecological and carcinogenicity risks of PAHs. Besides, the role of periphyton in enhancing the rice productivity was revealed. The results indicated that periphyton alleviated the oxidative stress of PAHs on rice by reducing malondialdehyde (MDA) content and increasing total antioxidant capacity (T-AOC). Periphyton reduced the toxic stress of PAHs on the soil by promoting soil carbon cycling and metabolic activities as well. Periphyton also improved the soil's physicochemical properties, such as the percentage of soil aggregate, the contents of humic substances (HSs) and nutrients, which increased rice biomass. These findings confirmed that periphyton could improve rice productivity by enhancing soil quality and health. This study provides a new eco-friendly strategy for soil remediation and simultaneously enables the production of safe crops on contaminated land.
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Affiliation(s)
- Su-Xin Li
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, No.2 Linggong Road, Dalian, 116024, PR China
| | - Xiao-Rong Gao
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, No.2 Linggong Road, Dalian, 116024, PR China.
| | - Jun Yi
- Key Laboratory of Edible Oil Quality and Safety for State Market Regulation, Wuhan, 430040, PR China
| | - Ling-Yun Jia
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, No.2 Linggong Road, Dalian, 116024, PR China
| | - Jun Ren
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, No.2 Linggong Road, Dalian, 116024, PR China
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Filipić B, Ušjak D, Rambaher MH, Oljacic S, Milenković MT. Evaluation of novel compounds as anti-bacterial or anti-virulence agents. Front Cell Infect Microbiol 2024; 14:1370062. [PMID: 38510964 PMCID: PMC10951914 DOI: 10.3389/fcimb.2024.1370062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 02/21/2024] [Indexed: 03/22/2024] Open
Abstract
Antimicrobial resistance is a global threat, leading to an alarming increase in the prevalence of bacterial infections that can no longer be treated with available antibiotics. The World Health Organization estimates that by 2050 up to 10 million deaths per year could be associated with antimicrobial resistance, which would equal the annual number of cancer deaths worldwide. To overcome this emerging crisis, novel anti-bacterial compounds are urgently needed. There are two possible approaches in the fight against bacterial infections: a) targeting structures within bacterial cells, similar to existing antibiotics; and/or b) targeting virulence factors rather than bacterial growth. Here, for the first time, we provide a comprehensive overview of the key steps in the evaluation of potential new anti-bacterial and/or anti-virulence compounds. The methods described in this review include: a) in silico methods for the evaluation of novel compounds; b) anti-bacterial assays (MIC, MBC, Time-kill); b) anti-virulence assays (anti-biofilm, anti-quorum sensing, anti-adhesion); and c) evaluation of safety aspects (cytotoxicity assay and Ames test). Overall, we provide a detailed description of the methods that are an essential tool for chemists, computational chemists, microbiologists, and toxicologists in the evaluation of potential novel antimicrobial compounds. These methods are cost-effective and have high predictive value. They are widely used in preclinical studies to identify new molecular candidates, for further investigation in animal and human trials.
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Affiliation(s)
- Brankica Filipić
- Department of Microbiology and Immunology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - Dušan Ušjak
- Laboratory for Molecular Biology, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia
| | - Martina Hrast Rambaher
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - Slavica Oljacic
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - Marina T. Milenković
- Department of Microbiology and Immunology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
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Kifelew LG, Warner MS, Morales S, Gordon DL, Thomas N, Mitchell JG, Speck PG. Lytic activity of phages against bacterial pathogens infecting diabetic foot ulcers. Sci Rep 2024; 14:3515. [PMID: 38347019 PMCID: PMC10861545 DOI: 10.1038/s41598-024-53317-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 01/30/2024] [Indexed: 02/15/2024] Open
Abstract
Complications of diabetes, such as diabetic foot ulcers (DFUs), are common, multifactorial in origin, and costly to treat. DFUs are the cause of nearly 90% of limb amputations among persons with diabetes. In most chronic infections such as DFU, biofilms are involved. Bacteria in biofilms are 100-1000 times more resistant to antibiotics than their planktonic counterparts. Multidrug-resistant (MDR) Staphylococcus aureus and Pseudomonas aeruginosa infections in DFUs may require alternative therapeutic agents such as bacteriophages ("phages"). This study describes the lytic activity of phage cocktails AB-SA01 (3-phage cocktail) and AB-PA01 (4-phage cocktail), which target S. aureus and P. aeruginosa, respectively. The host range and lytic effect of AB-SA01 and AB-PA01 on a planktonic culture, single-species biofilm, and mixed-species biofilm were evaluated. In vitro testing showed that 88.7% of S. aureus and 92.7% of P. aeruginosa isolates were susceptible to AB-SA01 and AB-PA01, respectively, in the planktonic state. The component phages of AB-SA01 and AB-PA01 infected 66% to 94.3% of the bacterial isolates tested. Furthermore, AB-SA01 and AB-PA01 treatment significantly (p < 0.05) reduced the biofilm biomass of their hosts, regardless of the antibiotic-resistant characteristics of the isolates and the presence of a non-susceptible host. In conclusion, the strong lytic activity, broad host range, and significant biofilm biomass reduction of AB-SA01 and AB-PA01 suggest the considerable potential of phages in treating antibiotic-resistant S. aureus and P. aeruginosa infections alone or as coinfections in DFUs.
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Affiliation(s)
- Legesse Garedew Kifelew
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia.
- St Paul's Hospital Millennium Medical College, 1271, Addis Ababa, Ethiopia.
| | - Morgyn S Warner
- Infectious Diseases Unit, Queen Elizabeth Hospital, Woodville, SA, 5011, Australia
- Discipline of Medicine, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Sandra Morales
- AmpliPhi Australia Pty Ltd., Brookvale, NSW, 2100, Australia
- Phage Consulting, Sydney, NSW, 2100, Australia
| | - David L Gordon
- Department of Microbiology and Infectious Diseases, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
| | - Nicky Thomas
- Basil Hetzel Institute for Translational Health Research, Woodville South, SA, 5011, Australia
- Centre for Pharmaceutical Innovation, University of South Australia, North Terrace, Adelaide, SA, 5000, Australia
| | - James G Mitchell
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Peter G Speck
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia.
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Coenye T. Biofilm antimicrobial susceptibility testing: where are we and where could we be going? Clin Microbiol Rev 2023; 36:e0002423. [PMID: 37812003 PMCID: PMC10732061 DOI: 10.1128/cmr.00024-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/27/2023] [Indexed: 10/10/2023] Open
Abstract
Our knowledge about the fundamental aspects of biofilm biology, including the mechanisms behind the reduced antimicrobial susceptibility of biofilms, has increased drastically over the last decades. However, this knowledge has so far not been translated into major changes in clinical practice. While the biofilm concept is increasingly on the radar of clinical microbiologists, physicians, and healthcare professionals in general, the standardized tools to study biofilms in the clinical microbiology laboratory are still lacking; one area in which this is particularly obvious is that of antimicrobial susceptibility testing (AST). It is generally accepted that the biofilm lifestyle has a tremendous impact on antibiotic susceptibility, yet AST is typically still carried out with planktonic cells. On top of that, the microenvironment at the site of infection is an important driver for microbial physiology and hence susceptibility; but this is poorly reflected in current AST methods. The goal of this review is to provide an overview of the state of the art concerning biofilm AST and highlight the knowledge gaps in this area. Subsequently, potential ways to improve biofilm-based AST will be discussed. Finally, bottlenecks currently preventing the use of biofilm AST in clinical practice, as well as the steps needed to get past these bottlenecks, will be discussed.
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Affiliation(s)
- Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
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Vanderpool EJ, Rumbaugh KP. Host-microbe interactions in chronic rhinosinusitis biofilms and models for investigation. Biofilm 2023; 6:100160. [PMID: 37928619 PMCID: PMC10622848 DOI: 10.1016/j.bioflm.2023.100160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 11/07/2023] Open
Abstract
Chronic rhinosinusitis (CRS) is a debilitating condition characterized by long-lasting inflammation of the paranasal sinuses. It affects a significant portion of the population, causing a considerable burden on individuals and healthcare systems. The pathogenesis of CRS is multifactorial, with bacterial infections playing a crucial role in CRS development and persistence. In recent years, the presence of biofilms has emerged as a key contributor to the chronicity of sinusitis, further complicating treatment and exacerbating symptoms. This review aims to explore the role of biofilms in CRS, focusing on the involvement of the bacterial species Staphylococcus aureus and Pseudomonas aeruginosa, their interactions in chronic infections, and model systems for studying biofilms in CRS. These species serve as an example of how microbial interplay can influence disease progression and exemplify the need for continued investigation and innovation in CRS research.
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Affiliation(s)
- Emily J. Vanderpool
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Burn Center of Research Excellence, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Kendra P. Rumbaugh
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Burn Center of Research Excellence, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX, USA
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Kraft L, Ribeiro VST, Gonçalves GA, Suss PH, Tuon FF. Comparison of amphotericin B lipid complex, deoxycholate amphotericin B, fluconazole, and anidulafungin activity against Candida albicans biofilm isolated from breakthrough candidemia. ENFERMEDADES INFECCIOSAS Y MICROBIOLOGIA CLINICA (ENGLISH ED.) 2023; 41:596-603. [PMID: 36707288 DOI: 10.1016/j.eimce.2022.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/19/2022] [Indexed: 01/26/2023]
Abstract
INTRODUCTION Biofilm formation causes virulence and resistance in Candida albicans. However, little is known about breakthrough candidemia isolates. We evaluated the antifungal activity of fluconazole, anidulafungin, deoxycholate amphotericin B (dAMB), and amphotericin B lipid complex (ABLC) against biofilms of C. albicans isolated from patients with breakthrough candidemia. METHODS The present study used strains of C. albicans isolated from breakthrough and non-breakthrough candidemia patients (control group). The susceptibility of planktonic cells to amphotericin B, anidulafungin, and fluconazole was determined by broth microdilution. Antifungal activity in sessile cells was evaluated using the minimum biofilm eradication concentration (MBEC), metabolic activity was estimated by reducing MTT, and biomass was estimated using crystal violet retention. RESULTS The planktonic strains were susceptible to amphotericin B, anidulafungin, and fluconazole, with minimum inhibitory concentrations of 1, ≤0.03, and 2mg/L, respectively. However, fluconazole and anidulafungin did not exert an antifungal effect on biofilms. Additionally, dAMB and ABCL reduced the metabolic activity and biomass. However, eradication was only achieved using 16mg/L dAMB. C. albicans isolates of breakthrough candidemia exhibited strong biofilm production, and the in vitro activity of available therapeutic options was poor. CONCLUSION In the present study, only dAMB and ABCL exhibited antibiofilm effects against sessile breakthrough candidemia isolates.
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Affiliation(s)
- Letícia Kraft
- Laboratory of Emerging Infectious Diseases, School of Medicine, Department of Health Sciences, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - Victoria Stadler Tasca Ribeiro
- Laboratory of Emerging Infectious Diseases, School of Medicine, Department of Health Sciences, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - Geiziane Aparecida Gonçalves
- Laboratory of Emerging Infectious Diseases, School of Medicine, Department of Health Sciences, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - Paula Hansen Suss
- Laboratory of Emerging Infectious Diseases, School of Medicine, Department of Health Sciences, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - Felipe Francisco Tuon
- Laboratory of Emerging Infectious Diseases, School of Medicine, Department of Health Sciences, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil.
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Han A, Lee SY. An overview of various methods for in vitro biofilm formation: a review. Food Sci Biotechnol 2023; 32:1617-1629. [PMID: 37780598 PMCID: PMC10533769 DOI: 10.1007/s10068-023-01425-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/25/2023] [Accepted: 08/24/2023] [Indexed: 10/03/2023] Open
Abstract
Biofilms are widely present in the natural environment and are difficult to remove as they are a survival strategy of microorganisms. Thus, the importance of studying biofilms is being increasingly recognized in food, medical, dental, and water quality-related industries. While research on biofilm detection methods is actively progressing, research on biofilm formation is not progressing rapidly. Moreover, there are few standardized methods because biofilm formation is affected by various factors. However, comprehensive knowledge of biofilm formation is essential to select a suitable method for research purposes. To better understand the various in vitro biofilm formation methods, the principles and characteristics of each method are explained in this review by dividing the methods into static and dynamic systems. In addition, the applications of biofilm research based on various assays are also discussed.
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Affiliation(s)
- Areum Han
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-dearo, Anseong-si, Gyeonggi-do 17546 Republic of Korea
| | - Sun-Young Lee
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-dearo, Anseong-si, Gyeonggi-do 17546 Republic of Korea
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12
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Mansouri M, Sadeghpoor M, Jahangiri A, Ghaini MH, Rasooli I. Enhanced immunoprotection against Acinetobacter baumannii infection: Synergistic effects of Bap and BauA in a murine model. Immunol Lett 2023; 262:18-26. [PMID: 37652189 DOI: 10.1016/j.imlet.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/26/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
BACKGROUND The rise of multi-drug resistant Acinetobacter baumannii poses a grave threat to hospital settings, resulting in increased mortality rates and garnering global attention. The formation of biofilms facilitated by biofilm-associated protein (Bap) and the iron absorption capabilities mediated by Baumannii acinetobactin utilization A (BauA) contribute to the persistence and survival of multidrug-resistant strains. In this study, we aimed to investigate the potential of disrupting the function of BauA and Bap simultaneously as a strategy for controlling A. baumannii. METHODS Recombinant Bap and BauA were expressed, purified, and subcutaneously administered individually and in combination to BALB/c mice. Subsequently, mice were intraperitoneally challenged with A. baumannii, and the bacterial load and tissue damage in the spleen, lung, and liver were assessed. Serum samples were evaluated to determine antibody titers in surviving mice. RESULTS Specific IgG antibodies were significantly increased. A combination of the antigens resulted in enhanced titer of specific IgGs in comparison to either BauA or Bap alone. The antibodies remained stable over a seven-month period. The combination of Bap and BauA exhibited superior immunoprotection against A. baumannii infection compared to individual administration, resulting in a further reduction in bacterial load in the liver, spleen, and lungs. The histopathological analysis demonstrated successful protection of the tissues against A. baumannii-induced damage upon administration of the two immunogens. CONCLUSIONS The combination of Bap and BauA has the potential to target a broader range of A. baumannii strains, including those expressing either Bap or BauA, thereby increasing its efficacy against a diverse array of strains.
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Affiliation(s)
| | | | - Abolfazl Jahangiri
- Applied Microbiology Research Center, Systems biology and poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | | | - Iraj Rasooli
- Department of Biology, Shahed University, Tehran, Iran; Molecular Microbiology Research Center and Department of Biology, Shahed University, Tehran, Iran.
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13
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Mariano LC, Grenho L, Fernandes MH, de Sousa Gomes P. Integrative tissue, cellular and molecular responsiveness of an innovative ex vivo model of the Staphylococcus aureus-mediated bone infection. FASEB J 2023; 37:e23166. [PMID: 37650876 DOI: 10.1096/fj.202300287rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 07/21/2023] [Accepted: 08/14/2023] [Indexed: 09/01/2023]
Abstract
Osteomyelitis is a pathological condition of the bone, frequently associated with the presence of infectious agents - namely Staphylococcus aureus - that induce inflammation and tissue destruction. Recent advances in the understanding of its pathophysiology and the identification of innovative therapeutic approaches were gathered from experimental in vitro and in vivo systems. However, cell culture models offer limited representativeness of the cellular functionality and the cell-cell and cell-matrix interactions, further failing to mimic the three-dimensional tissue organization; and animal models allow for limited mechanistic assessment given the complex nature of systemic and paracrine regulatory systems and are endorsed with ethical constraints. Accordingly, this study aims at the establishment and assessment of a new ex vivo bone infection model, upon the organotypic culture of embryonic chicken femurs colonized with S. aureus, highlighting the model responsiveness at the molecular, cellular, and tissue levels. Upon infection with distinct bacterial inoculums, data reported an initial exponential bacterial growth, followed by diminished metabolic activity. At the tissue level, evidence of S. aureus-mediated tissue destruction was attained and demonstrated through distinct methodologies, conjoined with decreased osteoblastic/osteogenic and increased osteoclastic/osteoclastogenic functionalities-representative of the osteomyelitis clinical course. Overall, the establishment and characterization of an innovative bone tissue infection model that is simple, reproducible, easily manipulated, cost-effective, and simulates many features of human osteomyelitis, further allowing the maintenance of the bone tissue's three-dimensional morphology and cellular arrangement, was achieved. Model responsiveness was further demonstrated, showcasing the capability to improve the research pipeline in bone tissue infection-related research.
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Affiliation(s)
- Lorena Castro Mariano
- BoneLab-Laboratory for Bone Metabolism and Regeneration, Faculty of Dental Medicine, University of Porto, Porto, Portugal
- LAQV/REQUIMTE, University of Porto, Porto, Portugal
| | - Liliana Grenho
- BoneLab-Laboratory for Bone Metabolism and Regeneration, Faculty of Dental Medicine, University of Porto, Porto, Portugal
- LAQV/REQUIMTE, University of Porto, Porto, Portugal
| | - Maria Helena Fernandes
- BoneLab-Laboratory for Bone Metabolism and Regeneration, Faculty of Dental Medicine, University of Porto, Porto, Portugal
- LAQV/REQUIMTE, University of Porto, Porto, Portugal
| | - Pedro de Sousa Gomes
- BoneLab-Laboratory for Bone Metabolism and Regeneration, Faculty of Dental Medicine, University of Porto, Porto, Portugal
- LAQV/REQUIMTE, University of Porto, Porto, Portugal
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14
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Ong J, Godfrey R, Nazarian A, Tam J, Isaacson BM, Pasquina PF, Williams DL. Comparison of Staphylococcus aureus tolerance between antimicrobial blue light, levofloxacin, and rifampin. Front Microbiol 2023; 14:1158558. [PMID: 37303789 PMCID: PMC10248220 DOI: 10.3389/fmicb.2023.1158558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Background Bacterial biofilms readily develop on all medical implants, including percutaneous osseointegrated (OI) implants. With the growing rate of antibiotic resistance, exploring alternative options for managing biofilm-related infections is necessary. Antimicrobial blue light (aBL) is a unique therapy that can potentially manage biofilm-related infections at the skin-implant interface of OI implants. Antibiotics are known to have antimicrobial efficacy disparities between the planktonic and biofilm bacterial phenotypes, but it is unknown if this characteristic also pertains to aBL. In response, we developed experiments to explore this aspect of aBL therapy. Methods We determined minimum bactericidal concentrations (MBCs) and antibiofilm efficacies for aBL, levofloxacin, and rifampin against Staphylococcus aureus ATCC 6538 planktonic and biofilm bacteria. Using student t-tests (p < 0.05), we compared the efficacy profiles between the planktonic and biofilm states for the three independent treatments and a levofloxacin + rifampin combination. Additionally, we compared antimicrobial efficacy patterns for levofloxacin and aBL against biofilms as dosages increased. Results aBL had the most significant efficacy disparity between the planktonic and biofilm phenotypes (a 2.5 log10 unit difference). However, further testing against biofilms revealed that aBL had a positive correlation between increasing efficacy and exposure time, while levofloxacin encountered a plateau. While aBL efficacy was affected the most by the biofilm phenotype, its antimicrobial efficacy did not reach a maximum. Discussion/conclusion We determined that phenotype is an important characteristic to consider when determining aBL parameters for treating OI implant infections. Future research would benefit from expanding these findings against clinical S. aureus isolates and other bacterial strains, as well as the safety of long aBL exposures on human cells.
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Affiliation(s)
- Jemi Ong
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, United States
- Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States
| | - Rose Godfrey
- Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States
| | - Alexa Nazarian
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, United States
| | - Joshua Tam
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, United States
- Department of Dermatology, Harvard Medical School, Boston, MA, United States
| | - Brad M. Isaacson
- Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States
- The Geneva Foundation, Tacoma, WA, United States
- Department of Physical Medicine and Rehabilitation, The Musculoskeletal Injury Rehabilitation Research for Operational Readiness, Uniformed Services University, Bethesda, MD, United States
- The Center for Rehabilitation Sciences Research, Uniformed Services University, Bethesda, MD, United States
| | - Paul F. Pasquina
- The Center for Rehabilitation Sciences Research, Uniformed Services University, Bethesda, MD, United States
- Department of Rehabilitation, Walter Reed National Military Medical Center, Bethesda, MD, United States
| | - Dustin L. Williams
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, United States
- Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States
- The Center for Rehabilitation Sciences Research, Uniformed Services University, Bethesda, MD, United States
- Department of Pathology, University of Utah, Salt Lake City, UT, United States
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15
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Sharma A, Gupta AK, Devi B. Current trends in management of bacterial pathogens infecting plants. Antonie Van Leeuwenhoek 2023; 116:303-326. [PMID: 36683073 DOI: 10.1007/s10482-023-01809-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 01/08/2023] [Indexed: 01/24/2023]
Abstract
Plants are continuously challenged by different pathogenic microbes that reduce the quality and quantity of produce and therefore pose a serious threat to food security. Among them bacterial pathogens are known to cause disease outbreaks with devastating economic losses in temperate, tropical and subtropical regions throughout the world. Bacteria are structurally simple prokaryotic microorganisms and are diverse from a metabolic standpoint. Bacterial infection process mainly involves successful attachment or penetration by using extracellular enzymes, type secretion systems, toxins, growth regulators and by exploiting different molecules that modulate plant defence resulting in successful colonization. Theses bacterial pathogens are extremely difficult to control as they develop resistance to antibiotics. Therefore, attempts are made to search for innovative methods of disease management by the targeting bacterial virulence and manipulating the genes in host plants by exploiting genome editing methods. Here, we review the recent developments in bacterial disease management including the bioactive antimicrobial compounds, bacteriophage therapy, quorum-quenching mediated control, nanoparticles and CRISPR/Cas based genome editing techniques for bacterial disease management. Future research should focus on implementation of smart delivery systems and consumer acceptance of these innovative methods for sustainable disease management.
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Affiliation(s)
- Aditi Sharma
- College of Horticulture and Forestry, Thunag- Mandi, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, 173 230, India.
| | - A K Gupta
- Department of Plant Pathology, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, 173 230, India
| | - Banita Devi
- Department of Plant Pathology, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, 173 230, India
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16
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Synergistically enhancing the antibacterial and antibiofilm activities of anion exchange membrane by chemically assembling gentamicin and N-chloramine layers. J Memb Sci 2023. [DOI: 10.1016/j.memsci.2023.121530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
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17
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Öztürk FY, Darcan C, Kariptaş E. The Determination, Monitoring, Molecular Mechanisms and Formation of Biofilm in E. coli. Braz J Microbiol 2023; 54:259-277. [PMID: 36577889 PMCID: PMC9943865 DOI: 10.1007/s42770-022-00895-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 12/16/2022] [Indexed: 12/30/2022] Open
Abstract
Biofilms are cell assemblies embedded in an exopolysaccharide matrix formed by microorganisms of a single or many different species. This matrix in which they are embedded protects the bacteria from external influences and antimicrobial effects. The biofilm structure that microorganisms form to protect themselves from harsh environmental conditions and survive is found in nature in many different environments. These environments where biofilm formation occurs have in common that they are in contact with fluids. The gene expression of bacteria in complex biofilm differs from that of bacteria in the planktonic state. The differences in biofilm cell expression are one of the effects of community life. Means of quorum sensing, bacteria can act in coordination with each other. At the same time, while biofilm formation provides many benefits to bacteria, it has positive and negative effects in many different areas. Depending on where they occur, biofilms can cause serious health problems, contamination risks, corrosion, and heat and efficiency losses. However, they can also be used in water treatment plants, bioremediation, and energy production with microbial fuel cells. In this review, the basic steps of biofilm formation and biofilm regulation in the model organism Escherichia coli were discussed. Finally, the methods by which biofilm formation can be detected and monitored were briefly discussed.
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Affiliation(s)
- Fırat Yavuz Öztürk
- Department of Molecular Biology and Genetic, Faculty of Arts and Science, Bilecik Seyh Edebali University, Bilecik, Turkey.
| | - Cihan Darcan
- Department of Molecular Biology and Genetic, Faculty of Arts and Science, Bilecik Seyh Edebali University, Bilecik, Turkey
| | - Ergin Kariptaş
- Department of Medical Microbiology, Faculty of Medicine, Samsun University, Samsun, Turkey
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Crivello G, Fracchia L, Ciardelli G, Boffito M, Mattu C. In Vitro Models of Bacterial Biofilms: Innovative Tools to Improve Understanding and Treatment of Infections. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13050904. [PMID: 36903781 PMCID: PMC10004855 DOI: 10.3390/nano13050904] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 06/02/2023]
Abstract
Bacterial infections are a growing concern to the health care systems. Bacteria in the human body are often found embedded in a dense 3D structure, the biofilm, which makes their eradication even more challenging. Indeed, bacteria in biofilm are protected from external hazards and are more prone to develop antibiotic resistance. Moreover, biofilms are highly heterogeneous, with properties dependent on the bacteria species, the anatomic localization, and the nutrient/flow conditions. Therefore, antibiotic screening and testing would strongly benefit from reliable in vitro models of bacterial biofilms. This review article summarizes the main features of biofilms, with particular focus on parameters affecting biofilm composition and mechanical properties. Moreover, a thorough overview of the in vitro biofilm models recently developed is presented, focusing on both traditional and advanced approaches. Static, dynamic, and microcosm models are described, and their main features, advantages, and disadvantages are compared and discussed.
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Affiliation(s)
- G. Crivello
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy
| | - L. Fracchia
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “A. Avogadro”, Largo Donegani 2, 28100 Novara, Italy
| | - G. Ciardelli
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena, Italy
| | - M. Boffito
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy
| | - C. Mattu
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy
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Biofilm-Forming Bacteria Implicated in Complex Otitis Media in Children in the Post-Heptavalent Pneumococcal Conjugate Vaccine (PCV7) Era. Microorganisms 2023; 11:microorganisms11030545. [PMID: 36985119 PMCID: PMC10056165 DOI: 10.3390/microorganisms11030545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/16/2023] [Accepted: 02/16/2023] [Indexed: 02/24/2023] Open
Abstract
Background: Chronic media with effusion (COME) and recurrent acute otitis media (RAOM) are closely related clinical entities that affect childhood. The aims of the study were to investigate the microbiological profile of otitis-prone children in the post-PCV7 era and, to examine the biofilm-forming ability in association with clinical history and outcome during a two-year post-operative follow-up. Methods: In this prospective study, pathogens from patients with COME and RAOM were isolated and studied in vitro for their biofilm-forming ability. The minimum inhibitory concentrations (MIC) of both the planktonic and the sessile forms were compared. The outcome of the therapeutic method used in each case and patient history were correlated with the pathogens and their ability to form biofilms. Results: Haemophilus influenzae was the leading pathogen (35% in COME and 40% in RAOM), and Streptococcus pneumoniae ranked second (12% in COME and 24% in RAOM). Polymicrobial infections were identified in 5% of COME and 19% of RAOM cases. Of the isolated otopathogens, 94% were positive for biofilm formation. Conclusions: This is the first Greek research studying biofilm formation in complex otitis media-prone children population in the post-PCV7 era. High rates of polymicrobial infections, along with treatment failure in biofilms, may explain the lack of antimicrobial efficacy in otitis-prone children.
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MBRA-2: a Modified Chemostat System to Culture Biofilms. Microbiol Spectr 2023; 11:e0292822. [PMID: 36475832 PMCID: PMC9927502 DOI: 10.1128/spectrum.02928-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Culture-dependent approaches for investigating microbial ecology aim to model the nutrient content of specific environments by simplifying the system for high-resolution molecular analysis. These in vitro systems are enticing due to their increased throughput compared to animal models, flexibility in modulating nutrient content and community composition, scaling of culture volume to isolate biological molecules, and control of environmental parameters, such as temperature, humidity, and nutrient flow. However, different devices are used to investigate homogenous, planktonic microbial communities and heterogeneous biofilms. Here, we present the minibioreactor array 2 (MBRA-2) with media rails, a benchtop multireactor system derived from the MBRA system that enables researchers to use the same system to grow planktonic and biofilm cultures. We simplified flow through the system and reduced contamination, leakage, and time required for array assembly by designing and implementing a reusable media rail to replace the branched tubing traditionally used to convey media through chemostat arrays. Additionally, we altered the structure of the six-bioreactor strip to incorporate a removable lid to provide easy access to the bioreactor wells, enabling biofilm recovery and thorough cleaning for reuse. Using Pseudomonas aeruginosa, a model biofilm-producing organism, we show that the technical improvements of the MBRA-2 for biofilms growth does not disrupt the function of the bioreactor array. IMPORTANCE The MBRA-2 with media rails provides an accessible system for investigators to culture heterogenous, suspended biofilms under constant flow.
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Sedghizadeh PP, Cherian P, Roshandel S, Tjokro N, Chen C, Junka AF, Hu E, Neighbors J, Pawlak J, Russell RGG, McKenna CE, Ebetino FH, Sun S, Sodagar E. Real-Time Impedance-Based Monitoring of the Growth and Inhibition of Osteomyelitis Biofilm Pathogen Staphylococcus aureus Treated with Novel Bisphosphonate-Fluoroquinolone Antimicrobial Conjugates. Int J Mol Sci 2023; 24:ijms24031985. [PMID: 36768310 PMCID: PMC9915994 DOI: 10.3390/ijms24031985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023] Open
Abstract
Osteomyelitis is a limb- and life-threatening orthopedic infection predominantly caused by Staphylococcus aureus biofilms. Bone infections are extremely challenging to treat clinically. Therefore, we have been designing, synthesizing, and testing novel antibiotic conjugates to target bone infections. This class of conjugates comprises bone-binding bisphosphonates as biochemical vectors for the delivery of antibiotic agents to bone minerals (hydroxyapatite). In the present study, we utilized a real-time impedance-based assay to study the growth of Staphylococcus aureus biofilms over time and to test the antimicrobial efficacy of our novel conjugates on the inhibition of biofilm growth in the presence and absence of hydroxyapatite. We tested early and newer generation quinolone antibiotics (ciprofloxacin, moxifloxacin, sitafloxacin, and nemonoxacin) and several bisphosphonate-conjugated versions of these antibiotics (bisphosphonate-carbamate-sitafloxacin (BCS), bisphosphonate-carbamate-nemonoxacin (BCN), etidronate-carbamate-ciprofloxacin (ECC), and etidronate-carbamate-moxifloxacin (ECX)) and found that they were able to inhibit Staphylococcus aureus biofilms in a dose-dependent manner. Among the conjugates, the greatest antimicrobial efficacy was observed for BCN with an MIC of 1.48 µg/mL. The conjugates demonstrated varying antimicrobial activity depending on the specific antibiotic used for conjugation, the type of bisphosphonate moiety, the chemical conjugation scheme, and the presence or absence of hydroxyapatite. The conjugates designed and tested in this study retained the bone-binding properties of the parent bisphosphonate moiety as confirmed using high-performance liquid chromatography. They also retained the antimicrobial activity of the parent antibiotic in the presence or absence of hydroxyapatite, albeit at lower levels due to the nature of their chemical modification. These findings will aid in the optimization and testing of this novel class of drugs for future applications to pharmacotherapy in osteomyelitis.
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Affiliation(s)
- Parish P. Sedghizadeh
- Division of Periodontology, Diagnostic Sciences and Dental Hygiene, Infection and Immunity Laboratory, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90007, USA
| | | | | | - Natalia Tjokro
- Division of Periodontology, Diagnostic Sciences and Dental Hygiene, Infection and Immunity Laboratory, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90007, USA
| | - Casey Chen
- Division of Periodontology, Diagnostic Sciences and Dental Hygiene, Infection and Immunity Laboratory, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90007, USA
| | - Adam F. Junka
- Department of Pharmaceutical Microbiology and Parasitology, Medical University of Wroclaw, 50-367 Wroclaw, Poland
| | - Eric Hu
- BioVinc LLC, Pasadena, CA 91107, USA
| | - Jeffrey Neighbors
- BioVinc LLC, Pasadena, CA 91107, USA
- Department of Pharmacology and Medicine, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Jacek Pawlak
- Medical Department, Lazarski University, 02-662 Warsaw, Poland
| | - R. Graham G. Russell
- The Botnar Research Centre, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford OX1 2JD, UK
- The Mellanby Centre for Bone Research, Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2TN, UK
| | - Charles E. McKenna
- Department of Chemistry, University of Southern California, Los Angeles, CA 90007, USA
| | | | - Shuting Sun
- BioVinc LLC, Pasadena, CA 91107, USA
- Correspondence: (S.S.); (E.S.); Tel.: +1-(213)-249-3116 (S.S.); +1-(213)-740-5184 (E.S.)
| | - Esmat Sodagar
- Division of Periodontology, Diagnostic Sciences and Dental Hygiene, Infection and Immunity Laboratory, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90007, USA
- Correspondence: (S.S.); (E.S.); Tel.: +1-(213)-249-3116 (S.S.); +1-(213)-740-5184 (E.S.)
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Shinu P. Antimicrobial Resistance, Phenotypic Characteristics, and Biofilm Production in Citrobacter freundii Isolates Obtained from Urinary Tract Infections. J Pharmacol Pharmacother 2023. [DOI: 10.1177/0976500x221147747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Objective To evaluate the link between phenotypic traits, antimicrobial resistance, and biofilm-producing capacity of urinary isolates of Citrobacter freundii ( C. freundii). Methods Both pan-antibiotic-susceptible and -resistant C. freundii isolates ( n = 120) obtained from laboratory-confirmed urinary tract infections were analyzed for their link between antimicrobial resistance, phenotypic characteristics, and biofilm production. Results Of the total C. freundii isolates ( n = 120), 30% (37/120) of them formed large colonies. Among the total large colonies produced ( n = 37), they were present in 21.62%, 10.81%, 13.5%, 16.2%, 21.62%, and 16.21% in the control group, CIP-group, FOS-group, COT-group, Gent-group, and ESBL groups, respectively. Compared to the pan-susceptible isolates, the occurrence of large-sized-colony-forming strains was relatively reduced in most of the drug-resistant groups. The overall distribution of mucoid colonies produced ( n = 54) includes 9.25%, 18.51%, 16.66%, 18.51%, 20.3%, and 16.66% in the control group, CIP-group, FOS-group, COT-group, Gent-group, and ESBL groups, respectively. Of the total isolates that produced biofilm ( n = 51), 11.76% of isolates showed biofilm formation in the control group. Alternatively, the rate was found to be 15.68%, 11.76%, 25.49%, 19.6%, and 15.68% in the CIP-group, FOS-group, SXT-group, Gen-group, and ESBL-groups, respectively. Conclusion This study correlates the association between phenotypic characteristics, antimicrobial resistance, and biofilm production, the three main characteristics of C. freundii.
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Affiliation(s)
- Pottathil Shinu
- Department of Biomedical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa, Saudi Arabia
- Department of Microbiology, M.M. Institute of Medical Sciences and Research, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, Haryana, India
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Torrez WB, Figueiredo LC, Santos TDS, Soares GM, Pingueiro JMS, Pereira da Silva HD, Malheiros Z, Stewart B, Feres M, Bueno-Silva B. Incorporation of zinc into cetylpyridinium chloride mouthwash affects the composition of multispecies biofilms. BIOFOULING 2023; 39:1-7. [PMID: 36656051 DOI: 10.1080/08927014.2022.2160242] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
This study evaluated the effect of a mouthwash containing 0.075% cetylpyridinium chloride and 0.28% zinc lactate (CPC + Zn) in a multispecies biofilm model. A 7-days 33-species biofilm, formed on Calgary device, was 1-min treated with: 0.12% chlorhexidine (CHX), culture medium (negative control), 0.075% cetylpyridinium chloride (CPC) or CPC + Zn, 2x/day, from day 3 until day 6. The metabolic activity and the microbial composition were evaluated by colorimetric method and checkerboard DNA-DNA hybridization, respectively. The three antimicrobials (CPC, CPC + Zn and CHX) reduced metabolic activity, total biofilm count and several species counts, including Porphyromonas gingivalis, Fusobacterium nucleatum, Parvimonas micra, Campylobacter gracilis and Streptococcus mutans. However, only CPC + Zn reduced counts of the pathogen Prevotella intermedia and did not interfere with the levels of some beneficial species in relation to the negative control. The treatment of multispecies subgingival biofilm with CPC + Zn was effective in controlling periodontal pathogens and favored the colonization of health-associated bacterial species.
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Affiliation(s)
- Willy Bustillos Torrez
- Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
- Research Department, Universidad Privada Franz Tamayo (UNIFRANZ), Cochabamba, Bolivia
| | - Luciene Cristina Figueiredo
- Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
| | | | - Geisla Mary Soares
- Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil
| | | | | | - Zilson Malheiros
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
- Colgate-Palmolive Technology Center, Piscataway, New Jersey, USA
| | - Bernal Stewart
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
- Colgate-Palmolive Technology Center, Piscataway, New Jersey, USA
| | - Magda Feres
- Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
| | - Bruno Bueno-Silva
- Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil
- Latin American Oral Health Association, São Paulo, São Paulo, Brazil
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Biofilm antimicrobial susceptibility through an experimental evolutionary lens. NPJ Biofilms Microbiomes 2022; 8:82. [PMID: 36257971 PMCID: PMC9579162 DOI: 10.1038/s41522-022-00346-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 10/04/2022] [Indexed: 11/19/2022] Open
Abstract
Experimental evolution experiments in which bacterial populations are repeatedly exposed to an antimicrobial treatment, and examination of the genotype and phenotype of the resulting evolved bacteria, can help shed light on mechanisms behind reduced susceptibility. In this review we present an overview of why it is important to include biofilms in experimental evolution, which approaches are available to study experimental evolution in biofilms and what experimental evolution has taught us about tolerance and resistance in biofilms. Finally, we present an emerging consensus view on biofilm antimicrobial susceptibility supported by data obtained during experimental evolution studies.
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25
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Kouijzer JJP, Noordermeer DJ, van Leeuwen WJ, Verkaik NJ, Lattwein KR. Native valve, prosthetic valve, and cardiac device-related infective endocarditis: A review and update on current innovative diagnostic and therapeutic strategies. Front Cell Dev Biol 2022; 10:995508. [PMID: 36263017 PMCID: PMC9574252 DOI: 10.3389/fcell.2022.995508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 09/06/2022] [Indexed: 11/13/2022] Open
Abstract
Infective endocarditis (IE) is a life-threatening microbial infection of native and prosthetic heart valves, endocardial surface, and/or indwelling cardiac device. Prevalence of IE is increasing and mortality has not significantly improved despite technological advances. This review provides an updated overview using recent literature on the clinical presentation, diagnosis, imaging, causative pathogens, treatment, and outcomes in native valve, prosthetic valve, and cardiac device-related IE. In addition, the experimental approaches used in IE research to improve the understanding of disease mechanisms and the current diagnostic pipelines are discussed, as well as potential innovative diagnostic and therapeutic strategies. This will ultimately help towards deriving better diagnostic tools and treatments to improve IE patient outcomes.
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Affiliation(s)
- Joop J. P. Kouijzer
- Thoraxcenter, Department of Biomedical Engineering, Erasmus MC University Medical Center, Rotterdam, Netherlands
- *Correspondence: Joop J. P. Kouijzer,
| | - Daniëlle J. Noordermeer
- Thoraxcenter, Department of Biomedical Engineering, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Wouter J. van Leeuwen
- Department of Cardiothoracic Surgery, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Nelianne J. Verkaik
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Kirby R. Lattwein
- Thoraxcenter, Department of Biomedical Engineering, Erasmus MC University Medical Center, Rotterdam, Netherlands
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Farjami A, Jalilzadeh S, Siahi-Shadbad M, Lotfipour F. The anti-biofilm activity of hydrogen peroxide against Escherichia coli strain FL-Tbz isolated from a pharmaceutical water system. JOURNAL OF WATER AND HEALTH 2022; 20:1497-1505. [PMID: 36308494 DOI: 10.2166/wh.2022.061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Biofilms are considered a significant reason for the failure of disinfection strategies in industrial water systems due to their resistance to antimicrobial agents. This study is designed to investigate the anti-biofilm activity of hydrogen peroxide (H2O2) at combinations of temperatures and contact times. For this purpose, an in vitro microtiter plate (MTP)-based model system was used for biofilm formation using Escherichia coli (E. coli) strain FL-Tbz isolated from the water system of a pharmaceutical plant. To investigate the anti-biofilm activity of H2O2, it was added at different concentrations (2-7% v/v) to biofilms and incubated at different temperatures (20-60 °C) for 10-40 min to find effective conditions to eradicate biofilms. Maximum biofilms were formed when bacterial suspensions were incubated at 37 °C for 96 h. The rate of biofilm formation using an environmental isolate was higher than that of standard strain. H2O2 at concentrations of ≥6.25% (v/v) at temperatures of ≥40 °C incubated for ≥25 min significantly eradicated the biofilms.
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Affiliation(s)
- Afsaneh Farjami
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran E-mail: ; Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sina Jalilzadeh
- Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammadreza Siahi-Shadbad
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran E-mail: ; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Farzaneh Lotfipour
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran E-mail: ; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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Comparison of amphotericin B lipid complex, deoxycholate amphotericin B, fluconazole, and anidulafungin activity against Candida albicans biofilm isolated from breakthrough candidemia. Enferm Infecc Microbiol Clin 2022. [DOI: 10.1016/j.eimc.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Gibbons SM, Gurry T, Lampe JW, Chakrabarti A, Dam V, Everard A, Goas A, Gross G, Kleerebezem M, Lane J, Maukonen J, Penna ALB, Pot B, Valdes AM, Walton G, Weiss A, Zanzer YC, Venlet NV, Miani M. Perspective: Leveraging the Gut Microbiota to Predict Personalized Responses to Dietary, Prebiotic, and Probiotic Interventions. Adv Nutr 2022; 13:1450-1461. [PMID: 35776947 PMCID: PMC9526856 DOI: 10.1093/advances/nmac075] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/31/2022] [Accepted: 06/28/2022] [Indexed: 01/28/2023] Open
Abstract
Humans often show variable responses to dietary, prebiotic, and probiotic interventions. Emerging evidence indicates that the gut microbiota is a key determinant for this population heterogeneity. Here, we provide an overview of some of the major computational and experimental tools being applied to critical questions of microbiota-mediated personalized nutrition and health. First, we discuss the latest advances in in silico modeling of the microbiota-nutrition-health axis, including the application of statistical, mechanistic, and hybrid artificial intelligence models. Second, we address high-throughput in vitro techniques for assessing interindividual heterogeneity, from ex vivo batch culturing of stool and continuous culturing in anaerobic bioreactors, to more sophisticated organ-on-a-chip models that integrate both host and microbial compartments. Third, we explore in vivo approaches for better understanding of personalized, microbiota-mediated responses to diet, prebiotics, and probiotics, from nonhuman animal models and human observational studies, to human feeding trials and crossover interventions. We highlight examples of existing, consumer-facing precision nutrition platforms that are currently leveraging the gut microbiota. Furthermore, we discuss how the integration of a broader set of the tools and techniques described in this piece can generate the data necessary to support a greater diversity of precision nutrition strategies. Finally, we present a vision of a precision nutrition and healthcare future, which leverages the gut microbiota to design effective, individual-specific interventions.
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Affiliation(s)
| | - Thomas Gurry
- Pharmaceutical Biochemistry group, School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland (PSI-WS), University of Geneva/University of Lausanne, Geneva, Switzerland
| | - Johanna W Lampe
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | | | - Veerle Dam
- Sensus BV (Royal Cosun), Roosendaal, The Netherlands
| | - Amandine Everard
- Metabolism and Nutrition Research Group, Louvain Drug Research Institute, Walloon Excellence in Life Sciences and BIOtechnology (WELBIO), UCLouvain, Université Catholique de Louvain, Brussels, Belgium
| | - Almudena Goas
- Department of Food, Nutrition, and Exercise Sciences, University of Surrey, Guildford, United Kingdom
| | - Gabriele Gross
- Medical and Scientific Affairs, Reckitt| Mead Johnson Nutrition Institute, Nijmegen, The Netherlands
| | - Michiel Kleerebezem
- Host Microbe Interactomics Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Jonathan Lane
- Health and Happiness Group, H&H Research, Cork, Ireland
| | | | - Ana Lucia Barretto Penna
- Department of Food Engineering and Technology, São Paulo State University, São José do Rio Preto, Brazil
| | - Bruno Pot
- Yakult Europe BV, Almere, The Netherlands
| | - Ana M Valdes
- Nottingham NIHR Biomedical Research Centre at the School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Gemma Walton
- Food and Nutritional Sciences, University of Reading, Reading, United Kingdom
| | - Adrienne Weiss
- Yili Innovation Center Europe, Wageningen, The Netherlands
| | | | - Naomi V Venlet
- International Life Sciences Institute, European Branch, Brussels, Belgium
| | - Michela Miani
- International Life Sciences Institute, European Branch, Brussels, Belgium
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Zhang Y, Lin S, Fu J, Zhang W, Shu G, Lin J, Li H, Xu F, Tang H, Peng G, Zhao L, Chen S, Fu H. Nanocarriers for combating biofilms: advantages and challenges. J Appl Microbiol 2022; 133:1273-1287. [PMID: 35621701 DOI: 10.1111/jam.15640] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 03/08/2022] [Accepted: 05/19/2022] [Indexed: 11/27/2022]
Abstract
Bacterial biofilms are highly resistant to antibiotics and pose a great threat to human and animal health. The control and removal of bacterial biofilms have become an important topic in the field of bacterial infectious diseases. Nanocarriers show great anti-biofilm potential because of their small particle size and strong permeability. In this review, the advantages of nanocarriers for combating biofilms are analyzed. Nanocarriers can act on all stages of bacterial biofilm formation and diffusion. They can improve the scavenging effect of biofilm by targeting biofilm, destroying extracellular polymeric substances, and enhancing the biofilm permeability of antimicrobial substances. Nanocarriers can also improve the antibacterial ability of antimicrobial drugs against bacteria in biofilm by protecting the loaded drugs and controlling the release of antimicrobial substances. Additionally, we emphasize the challenges faced in using nanocarrier formulations and translating them from a preclinical level to the clinical setting.
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Affiliation(s)
- Yuning Zhang
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Shiyu Lin
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Jingyuan Fu
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Wei Zhang
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Gang Shu
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Juchun Lin
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Haohuan Li
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Funeng Xu
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Huaqiao Tang
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Guangneng Peng
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Ling Zhao
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Shiqi Chen
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Hualin Fu
- Innovative Engineering Research Center of Veterinary Pharmaceutics, Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
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Luteolin Inhibits the Biofilm Formation and Cytotoxicity of Methicillin-Resistant Staphylococcus aureus via Decreasing Bacterial Toxin Synthesis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:4476339. [PMID: 35586693 PMCID: PMC9110164 DOI: 10.1155/2022/4476339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/31/2022] [Accepted: 04/19/2022] [Indexed: 12/02/2022]
Abstract
Owing to the fact that luteolin has antibacterial activity against Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA), its specific mechanism in MRSA is worthy of investigation, which is the focus of this study. Initially, the collected S. aureus strains were treated with luteolin. Then, the minimum inhibitory concentration (MIC) of luteolin against the S. aureus strains was measured by the broth microdilution. The growth curves, biofilm formation, and cytotoxicity of treated S. aureus were detected using a microplate reader. The live and dead bacteria were evaluated using confocal laser scanning microscopy, the bacterial morphology was observed using scanning electron microscopy, and the S. aureus colony-forming unit (CFU) numbers were assessed. The levels of alpha hemolysin (α-hemolysin), delta hemolysin (δ-hemolysin), and hlaA were detected via western blot and RT-PCR. The mortality of mouse model with S. aureus systemic infection was analyzed, and the levels of IL-6, IL-8, IL-10, and TNF-α were quantitated using ELISA. Concretely, the MIC of luteolin against MRSA N315 was 64 μg/mL. Luteolin at 16 μg/mL did not affect the growth of MRSA N315, but inhibited the biofilm formation and CFU, and promoted the morphological changes and death of MRSA N315. Luteolin decreased the cytotoxicity and the levels of α-hemolysin, δ-hemolysin, and hlaA in MRSA N315, elevated MRSA-reduced mice survival rate, and differentially modulated the inflammatory cytokine levels in MRSA-infected mice. Collectively, luteolin inhibits biofilm formation and cytotoxicity of MRSA via blocking the bacterial toxin synthesis.
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31
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Charalambous A, Grivogiannis E, Dieronitou I, Michael C, Rahme L, Apidianakis Y. Proteobacteria and Firmicutes Secreted Factors Exert Distinct Effects on Pseudomonas aeruginosa Infection under Normoxia or Mild Hypoxia. Metabolites 2022; 12:449. [PMID: 35629953 PMCID: PMC9146490 DOI: 10.3390/metabo12050449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 02/04/2023] Open
Abstract
Microbiota may alter a pathogen's virulence potential at polymicrobial infection sites. Here, we developed a multi-modal Drosophila assay, amenable to the assessment of human bacterial interactions using fly survival or midgut regeneration as a readout, under normoxia or mild hypoxia. Deploying a matrix of 12 by 33 one-to-one Drosophila co-infections via feeding, we classified bacterial interactions as neutral, synergistic, or antagonistic, based on fly survival. Twenty six percent of these interactions were antagonistic, mainly occurring between Proteobacteria. Specifically, Pseudomonas aeruginosa infection was antagonized by various Klebsiella strains, Acinetobacter baumannii, and Escherichia coli. We validated these interactions in a second screen of 7 by 34 one-to-one Drosophila co-infections based on assessments of midgut regeneration, and in bacterial co-culture test tube assays, where antagonistic interactions depended on secreted factors produced upon high sugar availability. Moreover, Enterococci interacted synergistically with P. aeruginosa in flies and in test tubes, enhancing the virulence and pyocyanin production by P. aeruginosa. However, neither lactic acid bacteria nor their severely hypoxic culture supernatants provided a survival benefit upon P. aeruginosa infection of flies or mice, respectively. We propose that at normoxic or mildly hypoxic sites, Firmicutes may exacerbate, whereas Proteobacteria secreted factors may ameliorate, P. aeruginosa infections.
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Affiliation(s)
- Anna Charalambous
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; (A.C.); (E.G.); (I.D.); (C.M.)
| | - Evangelos Grivogiannis
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; (A.C.); (E.G.); (I.D.); (C.M.)
| | - Irene Dieronitou
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; (A.C.); (E.G.); (I.D.); (C.M.)
| | - Christina Michael
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; (A.C.); (E.G.); (I.D.); (C.M.)
| | - Laurence Rahme
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA;
| | - Yiorgos Apidianakis
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; (A.C.); (E.G.); (I.D.); (C.M.)
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Georgiev K, Filipov I, Pecheva A. Biofilm reactor calibration for in vitro investigation of composite biodegradation. Folia Med (Plovdiv) 2022; 64:248-251. [DOI: 10.3897/folmed.64.e61540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/08/2021] [Indexed: 11/12/2022] Open
Abstract
Introduction: The majority of biodegradation studies of composite materials use simplified models of microbial biofilm despite the apparent diversity of the oral microbiota. The use of in vitro systems of “artificial mouth” design is a step towards clarifying the synergistic effect that microbial plaque and human saliva have on composite degradation.
Aim: Establishment of functional parameters for in vitro reproduction of oral biofilms via biofilm reactor systems.
Materials and methods: The CDC Biofilm Reactor system consists of eight polypropylene sticks. The rod cover and the retaining plates are mounted in a 1-dm glass cylinder with an outlet side opening. The laboratory bioreactor has a working volume of 340 ml. The device is equipped with a four-blade magnetic stirrer. The system also includes gauging appliances and executive mechanisms for controlling and adjusting the basic parameters of the process.
Results: Determination of the operating volume of the reactor is performed prior to the experiment along with the time of reach and stabilization of the set temperature in the design which is 60 min at 120 rpm. A mathematical model is used to calculate the rate of delivery of growth medium - 11 millilitres per minute. The bioreactor is sterilized by 0.3% neomycin solution for 24 hours. Prior to the experiment the system is cleansed (via passage) with sterile water for 60 minutes.
Conclusions: The pre-calibration of a bioreactor system allows specification and refinement of its working parameters, thus engaging for accurate reproduction of the environmental conditions in the oral cavity.
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Ndukwe ARN, Wiedbrauk S, Boase NRB, Fairfull-Smith KE. Strategies to improve the potency of oxazolidinones towards bacterial biofilms. Chem Asian J 2022; 17:e202200201. [PMID: 35352479 PMCID: PMC9321984 DOI: 10.1002/asia.202200201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/28/2022] [Indexed: 11/29/2022]
Abstract
Biofilms are part of the natural lifecycle of bacteria and are known to cause chronic infections that are difficult to treat. Most antibiotics are developed and tested against bacteria in the planktonic state and are ineffective against bacterial biofilms. The oxazolidinones, including the last resort drug linezolid, are one of the main classes of synthetic antibiotics progressed to clinical use in the last 50 years. They have a unique mechanism of action and only develop low levels of resistance in the clinical setting. With the aim of providing insight into strategies to design more potent antibiotic compounds with activity against bacterial biofilms, we review the biofilm activity of clinically approved oxazolidinones and report on structural modifications to oxazolidinones and their delivery systems which lead to enhanced anti‐biofilm activity.
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Affiliation(s)
- Audrey R N Ndukwe
- Queensland University of Technology - QUT: Queensland University of Technology, Faculty of Science, AUSTRALIA
| | - Sandra Wiedbrauk
- Queensland University of Technology - QUT: Queensland University of Technology, Faculty of Science, AUSTRALIA
| | - Nathan R B Boase
- Queensland University of Technology - QUT: Queensland University of Technology, Faculty of Science, AUSTRALIA
| | - Kathryn E Fairfull-Smith
- Queensland University of Technology Faculty of Science, Centre for Materials Science, 2 George St, 4001, Brisbane, AUSTRALIA
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AroC, a Chorismate Synthase, is Required for the Formation of Edwardsiella tarda biofilms. Microbes Infect 2022; 24:104955. [PMID: 35272020 DOI: 10.1016/j.micinf.2022.104955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 01/27/2022] [Accepted: 02/23/2022] [Indexed: 11/19/2022]
Abstract
Biofilms contribute to the resistance of Edwardsiella tarda to antibiotics and host immunity. AroC in the shikimate pathway produces chorismate to synthesize crucial intermediates such as indole. In this study, the differences between biofilms produced by aroC mutants (△aroC), wild-type (WT) strains, and △aroC complementary strains (C△aroC) were detected both in vitro with 96-well plates, tubes, or coverslips and in vivo using a mouse model of subcutaneous implants. When examining potential mechanisms, we found that the diameters of the movement rings in soft agar plates and the flagellar sizes and numbers determined by silver staining were all lower for △aroC than for WT and C△aroC. Moreover, qRT-PCR showed that the transcription levels of flagellar synthesis genes, fliA and fliC, were reduced in △aroC. AroC, FliC, or FliA may accompany the motility of △aroC strains. In addition, compared with the WT and C△aroC, the amounts of indole in △aroC were significantly decreased. Notably, the formation of biofilms by these strains could be promoted by exogenous indole. Therefore, the aroC gene could affect the biofilm formation of E. tarda concerning its impact on flagella and indole.
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Latorre MC, Alonso B, Cruces R, Sanz A, Muñoz P, Guembe M. The classification of Staphylococcus aureus strains by biofilm production differs depending on the method used. ENFERMEDADES INFECCIOSAS Y MICROBIOLOGIA CLINICA (ENGLISH ED.) 2022; 40:134-137. [PMID: 35249674 DOI: 10.1016/j.eimce.2020.11.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/01/2020] [Indexed: 06/14/2023]
Abstract
INTRODUCTION Strains can be classified in terms of biofilm production from quantitative absorbance values collectively by dividing strains into tertile ranks or individually by calculating the optical density for the negative control. However, these methods have not been compared in a large sample of Staphylococcus aureus strains. Therefore, our objective was to analyze the agreement between both methods in terms of biomass production and metabolic activity of their biofilm. METHODS We classified 233 S. aureus strains by biomass production and metabolic activity using the crystal violet and XTT assays, respectively. Strains were classified as low, moderate, or high biofilm producers according to tertile or optical density. RESULTS We found no agreement between both methods (p<0.001 and p=0.028, respectively). CONCLUSIONS We consider strains' biofilm classification by optical density to be a more reliable method, as it depends on the individual absorbance of each strain.
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Affiliation(s)
- María Consuelo Latorre
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañon, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañon, Madrid, Spain
| | - Beatriz Alonso
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañon, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañon, Madrid, Spain
| | - Raquel Cruces
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañon, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañon, Madrid, Spain
| | - Aurora Sanz
- School of Biology, Universidad Complutense de Madrid, Madrid, Spain
| | - Patricia Muñoz
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañon, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañon, Madrid, Spain; Medicine Department, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain; CIBER Enfermedades Respiratorias-CIBERES, Madrid, Spain
| | - María Guembe
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañon, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañon, Madrid, Spain.
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Marmion M, Macori G, Ferone M, Whyte P, Scannell A. Survive and thrive: Control mechanisms that facilitate bacterial adaptation to survive manufacturing-related stress. Int J Food Microbiol 2022; 368:109612. [DOI: 10.1016/j.ijfoodmicro.2022.109612] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/21/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
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Wang Z, Yin S, Chou Q, Zhou D, Jeppesen E, Wang L, Zhang W. Community-level and function response of photoautotrophic periphyton exposed to oxytetracycline hydrochloride. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 294:118593. [PMID: 34864100 DOI: 10.1016/j.envpol.2021.118593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/17/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
Periphyton is considered important for removal of organic pollutants from water bodies, but knowledge of the impacts of antibiotics on the community structure and ecological function of waterbodies remains limited. In this study, the effects of oxytetracycline hydrochloride (OTC) on the communities of photoautotrophic epilithon and epipelon and its effect on nitrogen and phosphorus concentrations in the water column were studied in a 12-day mesocosm experiment. The dynamics of nitrogen and phosphorus concentrations in the epipelon and epilithon experiment showed similar patterns. The concentrations of total nitrogen, dissolved total nitrogen, ammonium nitrogen, total phosphorus and dissolved total phosphorus in the water column increased rapidly during the initial days of exposure, after which a downward trend occurred. In the epilithon experiment, we found that the photosynthesis (Fv/Fm) and biomass of epilithon were significantly (P < 0.05) stimulated in the low concentration group. Contrarily, growth and photosynthesis (Fv/Fm) were significantly (P < 0.05) reduced in the medium and high concentration group. We further found that the photosynthetic efficiency of photoautotrophic epilithon was negatively correlated with the concentrations of nitrogen and phosphorus in the water column (P < 0.05). Principal coordinate analysis (PCoA) showed that the communities of epilithic algae in the control group and in the low concentration group were significantly (P < 0.05) different from that of the high concentration group during the initial 4 days. After 8 days' exposure, all groups tended to be similar, indicating that epilithon showed rapid adaptability and/or resilience. Similar results were found for the relative abundance of some epilithic algae. Our findings indicate that the biofilm system has strong tolerance and adaptability to OTC as it recovered fast after an initial suppression, thus showing the important role of periphyton in maintaining the dynamic balance of nutrients with other processes in aquatic ecosystems.
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Affiliation(s)
- Zhenfang Wang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Sicheng Yin
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Qingchuan Chou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China
| | - Dong Zhou
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China; Shanghai National Engineering Center of Urban Water Resources CO., LTD, Shanghai, 201306, China
| | - Erik Jeppesen
- Department of Bioscience, Aarhus University, Silkeborg, 8600, Denmark; Sino-Danish Centre for Education and Research (SDC), University of Chinese Academy of Sciences, Beijing, 100049, China; Limnology Laboratory and EKOSAM, Department of Biological Sciences, Middle East Technical University, Ankara, 06800, Turkey; Institute of Marine Sciences, Middle East Technical University, Mersin, 33731, Turkey
| | - Liqing Wang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Wei Zhang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China.
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Luo TL, Vanek ME, Gonzalez-Cabezas C, Marrs CF, Foxman B, Rickard AH. In vitro model systems for exploring oral biofilms: From single-species populations to complex multi-species communities. J Appl Microbiol 2022; 132:855-871. [PMID: 34216534 PMCID: PMC10505481 DOI: 10.1111/jam.15200] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/05/2021] [Accepted: 06/29/2021] [Indexed: 12/13/2022]
Abstract
Numerous in vitro biofilm model systems are available to study oral biofilms. Over the past several decades, increased understanding of oral biology and advances in technology have facilitated more accurate simulation of intraoral conditions and have allowed for the increased generalizability of in vitro oral biofilm studies. The integration of contemporary systems with confocal microscopy and 16S rRNA community profiling has enhanced the capabilities of in vitro biofilm model systems to quantify biofilm architecture and analyse microbial community composition. In this review, we describe several model systems relevant to modern in vitro oral biofilm studies: the constant depth film fermenter, Sorbarod perfusion system, drip-flow reactor, modified Robbins device, flowcells and microfluidic systems. We highlight how combining these systems with confocal microscopy and community composition analysis tools aids exploration of oral biofilm development under different conditions and in response to antimicrobial/anti-biofilm agents. The review closes with a discussion of future directions for the field of in vitro oral biofilm imaging and analysis.
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Affiliation(s)
- Ting L. Luo
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Michael E. Vanek
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Carlos Gonzalez-Cabezas
- Department of Cariology, Restorative Sciences and Endodontics, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Carl F. Marrs
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Betsy Foxman
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Alexander H. Rickard
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
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Anjum M, Laitila A, Ouwehand AC, Forssten SD. Current Perspectives on Gastrointestinal Models to Assess Probiotic-Pathogen Interactions. Front Microbiol 2022; 13:831455. [PMID: 35173703 PMCID: PMC8841803 DOI: 10.3389/fmicb.2022.831455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/06/2022] [Indexed: 12/12/2022] Open
Abstract
There are different models available that mimic the human intestinal epithelium and are thus available for studying probiotic and pathogen interactions in the gastrointestinal tract. Although, in vivo models make it possible to study the overall effects of a probiotic on a living subject, they cannot always be conducted and there is a general commitment to reduce the use of animal models. Hence, in vitro methods provide a more rapid tool for studying the interaction between probiotics and pathogens; as well as being ethically superior, faster, and less expensive. The in vitro models are represented by less complex traditional models, standard 2D models compromised of culture plates as well as Transwell inserts, and newer 3D models like organoids, enteroids, as well as organ-on-a-chip. The optimal model selected depends on the research question. Properly designed in vitro and/or in vivo studies are needed to examine the mechanism(s) of action of probiotics on pathogens to obtain physiologically relevant results.
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Affiliation(s)
| | | | | | - Sofia D. Forssten
- International Flavors and Fragrances, Health and Biosciences, Danisco Sweeteners Oy, Kantvik, Finland
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40
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Vyas HKN, Xia B, Mai-Prochnow A. Clinically relevant in vitro biofilm models: A need to mimic and recapitulate the host environment. Biofilm 2022; 4:100069. [PMID: 36569981 PMCID: PMC9782257 DOI: 10.1016/j.bioflm.2022.100069] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 12/27/2022] Open
Abstract
Biofilm-associated infections are difficult to treat and eradicate because of their increased antimicrobial tolerance. In vitro biofilm models have enabled the high throughput testing of an array of differing novel antimicrobials and treatment strategies. However, biofilms formed in these oftentimes basic in vitro systems do not resemble biofilms seen in vivo. As a result, translatability from the lab to the clinic is poor or limited. To improve translatability, in vitro models must better recapitulate the host environment. This review describes and critically evaluates new and innovative in vitro models that better mimic the environments of a variety of clinically important, biofilm-associated infections of the skin, oropharynx, lungs, and infections related to indwelling implants and medical devices. This review highlights that many of these models represent considerable advances in the field of biofilm research and help to translate laboratory findings into the clinical practice.
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Farjami A, Hatami MS, Siahi-Shadbad M, Lotfipour F. Peracetic acid Activity on Biofilm Formed by Escherichia coli Isolated from an Industrial Water System. Lett Appl Microbiol 2022; 74:613-621. [PMID: 34984695 DOI: 10.1111/lam.13647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 12/26/2021] [Accepted: 12/28/2021] [Indexed: 11/30/2022]
Abstract
One of the major problems in industrial water systems is the generation of biofilm, which is resistant to antimicrobial agents and causes failure of sanitization policy. This work aimed to study the anti-biofilm activity of peracetic acid (PAA) at contact times and temperatures combinations. To this end, a 96 well microtiter-based calorimetric method was applied in in vitro biofilm production using Ecsherichia coli, isolated from the water supply system of a pharmaceutical plant. The phenotypic and phylogenetic tests confirmed the isolated bacteria belong to strains of Ecsherichia coli. The anti-biofilm activity of peracetic acid on formed biofilm was investigated at concentrations of 0.15-0.5% for a contact time of 5-15 min at 20°C to 60°C. The maximum biofilm formation by MTP method using an Ecsherichia coli isolate was achieved in 96 h incubation in TSB containing wells at 37°C. Biofilm formation rate showed to be high by the environmental isolate compared with that of standard strain. PAA at concentrations above 0.25%, the temperature of 40°C, and a minimum of 10 minutes of contact time was effective in the eradication of biofilm in an MPT-based system.
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Affiliation(s)
- Afsaneh Farjami
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mohammadreza Siahi-Shadbad
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Farzaneh Lotfipour
- Food and Drug Safety Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Wieland T, Kotthaus K, Bürkin EI, Engesser F, Altenburger MJ, Ledernez L, Urban GA, Bergmann ME. Analysis of the Effects of Disinfectants and Plasma Treatment on Biofilm Growth by a Thermal Flow Sensor for Real-Time Measurements. PLASMA MEDICINE 2022. [DOI: 10.1615/plasmamed.2022044566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Coenye T, Spittaels KJ, Achermann Y. The role of biofilm formation in the pathogenesis and antimicrobial susceptibility of Cutibacterium acnes. Biofilm 2021; 4:100063. [PMID: 34950868 PMCID: PMC8671523 DOI: 10.1016/j.bioflm.2021.100063] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 12/20/2022] Open
Abstract
Cutibacterium acnes (previously known as Propionibacterium acnes) is frequently found on lipid-rich parts of the human skin. While C. acnes is most known for its role in the development and progression of the skin disease acne, it is also involved in many other types of infections, often involving implanted medical devices. C. acnes readily forms biofilms in vitro and there is growing evidence that biofilm formation by this Gram-positive, facultative anaerobic micro-organism plays an important role in vivo and is also involved in treatment failure. In this brief review we present an overview on what is known about C. acnes biofilms (including their role in pathogenesis and reduced susceptibility to antibiotics), discuss model systems that can be used to study these biofilms in vitro and in vivo and give an overview of interspecies interactions occurring in polymicrobial communities containing C. acnes.
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Affiliation(s)
- Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Gent, Belgium
| | - Karl-Jan Spittaels
- Laboratory of Pharmaceutical Microbiology, Ghent University, Gent, Belgium
| | - Yvonne Achermann
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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Probiotics as Therapeutic Tools against Pathogenic Biofilms: Have We Found the Perfect Weapon? MICROBIOLOGY RESEARCH 2021. [DOI: 10.3390/microbiolres12040068] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Bacterial populations inhabiting a variety of natural and human-associated niches have the ability to grow in the form of biofilms. A large part of pathological chronic conditions, and essentially all the bacterial infections associated with implanted medical devices or prosthetics, are caused by microorganisms embedded in a matrix made of polysaccharides, proteins, and nucleic acids. Biofilm infections are generally characterized by a slow onset, mild symptoms, tendency to chronicity, and refractory response to antibiotic therapy. Even though the molecular mechanisms responsible for resistance to antimicrobial agents and host defenses have been deeply clarified, effective means to fight biofilms are still required. Lactic acid bacteria (LAB), used as probiotics, are emerging as powerful weapons to prevent adhesion, biofilm formation, and control overgrowth of pathogens. Hence, using probiotics or their metabolites to quench and interrupt bacterial communication and aggregation, and to interfere with biofilm formation and stability, might represent a new frontier in clinical microbiology and a valid alternative to antibiotic therapies. This review summarizes the current knowledge on the experimental and therapeutic applications of LAB to interfere with biofilm formation or disrupt the stability of pathogenic biofilms.
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Kling KE, Maddox CW, Manfra Marretta S, Nowicki C, Schaeffer DJ. Effect of TrisEDTA and Chlorhexidine 0.12% on an In Vitro-Defined Biofilm Representing the Subgingival Plaque Biofilm of the Dog. J Vet Dent 2021; 39:9-20. [PMID: 34866484 DOI: 10.1177/08987564211058496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study was designed to investigate the effects of chlorhexidine 0.12%, TrisEDTA (tromethamine ethylenediamintetraacetic acid), and a combination of chlorhexidine 0.12% and TrisEDTA on an in vitro plaque biofilm model comprised of three bacterial species commonly found in canine subgingival plaque. Porphyromonas gulae, Actinomyces canis, and Neisseria canis were grown in a biofilm on polished hydroxyapatite coated titanium alloy pucks for 72 h prior to exposure to one of four test solutions: TrisEDTA, chlorhexidine 0.12%, a combination of TrisEDTA and chlorhexidine 0.12%, or sterile deionized water as a control. Following exposure to the test solution, a sample was collected of the biofilm either immediately or following 24 h of additional incubation in a broth medium. Lower numbers of CFU/mL of Porphyromonas gulae resulted when the biofilm was treated with a solution of chlorhexidine 0.12% and TrisEDTA compared to with chlorhexidine 0.12% alone, TrisEDTA alone, or the control and so this solution can be said to be synergistic against Porphyromonas gulae in this controlled in vitro model. Greater reductions in the numbers of CFU/mL of Actinomyces canis and Neisseria canis resulted from treatment with chlorhexidine 0.12% alone than if treated with the combination of TrisEDTA and chlorhexidine 0.12%. When treated biofilm samples were allowed 24 h of additional growth in fresh media, greater variance resulted and this variance highlights the complex dynamics involved in bacterial growth within a biofilm.
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Kim EJ, Hyun JE, Kang YH, Baek SJ, Hwang CY. In vitro antibacterial and antibiofilm effects of cold atmospheric microwave plasma against Pseudomonas aeruginosa causing canine skin and ear infections. Vet Dermatol 2021; 33:29-e10. [PMID: 34747063 DOI: 10.1111/vde.13030] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Pseudomonas aeruginosa is an opportunist pathogen that causes purulent inflammation in the skin and in the ears of dogs. Among the various virulence factors of P. aeruginosa, biofilms have been reported to result in antibiotic resistance, leading to therapeutic limitations. Cold atmospheric microwave plasma (CAMP) is known to have a high antimicrobial effect, which causes physical cell wall rupture and DNA damage. HYPOTHESIS/OBJECTIVES The objective of this study was to evaluate the antibacterial and antibiofilm effects of CAMP against planktonic bacteria and the biofilm of P. aeruginosa. METHODS AND MATERIALS The antibacterial effect of CAMP against P. aeruginosa ATCC10145 and clinical isolates (n = 30) was evaluated using the colony count method. We also assessed the effect of CAMP on biofilm of P. aeruginosa ATCC strain by the colony count method, water-soluble tetrazolium salt (WST) assay and confocal laser scanning microscopy (CLSM). RESULTS The complete eradication of P. aeruginosa (ATCC strain and clinical isolates) was achieved within 120 s at 50 W, and clinical isolates required 60 s shorter than the ATCC strain for complete eradication at 50 W. We also confirmed the time-dependent bactericidal effect of CAMP at 50 W against ATCC strain biofilm. CONCLUSIONS AND CLINICAL IMPORTANCE CAMP was effective against both planktonic bacteria and biofilm formation of P. aeruginosa. However, further studies on in vivo efficacy and safety in canine skin and ears are necessary to fully validate its clinical application.
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Affiliation(s)
- Eun-Joo Kim
- Laboratory of Veterinary Dermatology and the Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Korea
| | - Jae-Eun Hyun
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Korea
| | - Yeong-Hun Kang
- Laboratory of Veterinary Dermatology and the Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Korea
| | - Seung-Joon Baek
- Laboratory of Signal Transduction, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Korea
| | - Cheol-Yong Hwang
- Laboratory of Veterinary Dermatology and the Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Korea
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Efficacy of alpha-mangostin for antimicrobial activity against endodontopathogenic microorganisms in a multi-species bacterial-fungal biofilm model. Arch Oral Biol 2021; 133:105304. [PMID: 34775269 DOI: 10.1016/j.archoralbio.2021.105304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To determine the activity of alpha-mangostin on preformed bacterial-fungal multi-species biofilms in vitro, and to ascertain the impact on metabolic activity, biofilm structure and viability. DESIGN Inhibitory concentrations (ICs) for alpha-mangostin against planktonic cultures of Candida albicans, Enterococcus faecalis, Lactobacillus rhamnosus, and Streptococcus gordonii were determined using a standard broth microdilution method. Single and multi-species (all species 1:1:1:1) biofilms were grown on polystyrene coverslips in Roswell Park Memorial Institute Medium for 48 h. The biofilms were then exposed to 0.2% (w/v) alpha-mangostin for 24 h. These concentrations were selected based on pilot experiments and the solubility of these compounds. 2% (v/v) chlorhexidine was used as a positive control and Roswell Park Memorial Institute Medium as a negative control. The metabolic activity of the biofilms after exposure was measured using metabolic (XTT) assays. Biofilms were visualised and quantified using fluorescent BacLight™ LIVE/DEAD staining. The biofilms were assessed for cell viability by culture and colony counting (CFU/mL). RESULTS 8 mg/L of alpha-mangostin was cidal against planktonic bacteria and 1000 mg/L for Candida. Alpha-mangostin was most active against L. rhamonosus biofilms and least active against C. albicans biofilm (metabolism inhibited by 99% and 78%, respectively). Alpha-mangostin exposure reduced the number of viable cells in the biofilms. CONCLUSION Alpha-mangostin inhibited the metabolic activity of bacterial-fungal biofilms effectively. The anti-biofilm activity of alpha-mangostin was comparable to chlorhexidine and thus has potential as a novel agent for endodontic therapy.
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Nazeam JA, Ragab GM, El-Gazar AA, El-Mancy SS, Jamil L, Fayez SM. Topical Nano Clove/Thyme Gel against Genetically Identified Clinical Skin Isolates: In Vivo Targeting Behavioral Alteration and IGF-1/pFOXO-1/PPAR γ Cues. Molecules 2021; 26:molecules26185608. [PMID: 34577079 PMCID: PMC8465895 DOI: 10.3390/molecules26185608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/03/2021] [Accepted: 09/06/2021] [Indexed: 11/16/2022] Open
Abstract
Antimicrobial resistance is a dramatic global threat; however, the slow progress of new antibiotic development has impeded the identification of viable alternative strategies. Natural antioxidant-based antibacterial approaches may provide potent therapeutic abilities to effectively block resistance microbes' pathways. While essential oils (EOs) have been reported as antimicrobial agents, its application is still limited ascribed to its low solubility and stability characters; additionally, the related biomolecular mechanisms are not fully understood. Hence, the study aimed to develop a nano-gel natural preparation with multiple molecular mechanisms that could combat bacterial resistance in an acne vulgaris model. A nano-emulgel of thyme/clove EOs (NEG8) was designed, standardized, and its antimicrobial activity was screened in vitro and in vivo against genetically identified skin bacterial clinical isolates (Pseudomonas stutzeri, Enterococcus faecium and Bacillus thuringiensis). As per our findings, NEG8 exhibited bacteriostatic and potent biofilm inhibition activities. An in vivo model was also established using the commercially available therapeutic, adapalene in contra genetically identified microorganism. Improvement in rat behavior was reported for the first time and NEG8 abated the dermal contents/protein expression of IGF-1, TGF-β/collagen, Wnt/β-catenin, JAK2/STAT-3, NE, 5-HT, and the inflammatory markers; p(Ser536) NF-κBp65, TLR-2, and IL-6. Moreover, the level of dopamine, protective anti-inflammatory cytokine, IL-10 and PPAR-γ protein were enhanced, also the skin histological structures were improved. Thus, NEG8 could be a future potential topical clinical alternate to synthetic agents, with dual merit mechanism as bacteriostatic antibiotic action and non-antibiotic microbial pathway inhibitor.
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Affiliation(s)
- Jilan A. Nazeam
- Pharmacognosy Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt
- Correspondence: ; Tel.: +20-010-0302-1798
| | - Ghada M. Ragab
- Pharmacology and Toxicological Department, Faculty of Pharmacy, Misr University, Giza 12585, Egypt;
| | - Amira A. El-Gazar
- Pharmacology and Toxicological Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt;
| | - Shereen S. El-Mancy
- Pharmaceutics Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt; (S.S.E.-M.); (S.M.F.)
| | - Lina Jamil
- Microbiology and Immunology Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt;
| | - Sahar M. Fayez
- Pharmaceutics Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt; (S.S.E.-M.); (S.M.F.)
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El-Tarabily KA, El-Saadony MT, Alagawany M, Arif M, Batiha GE, Khafaga AF, Elwan HA, Elnesr SS, E. Abd El-Hack M. Using essential oils to overcome bacterial biofilm formation and their antimicrobial resistance. Saudi J Biol Sci 2021; 28:5145-5156. [PMID: 34466092 PMCID: PMC8380992 DOI: 10.1016/j.sjbs.2021.05.033] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/12/2021] [Accepted: 05/14/2021] [Indexed: 12/18/2022] Open
Abstract
The increase of resistant bacteria puts a huge pressure on the antimicrobials in current use. Antimicrobial resistance (AMR) results from antibiotic misuse and abuse over many years and is a global financial burden. New polices must be developed for the use of antimicrobials and to continue research efforts to mitigate AMR. It is essential to target the most harmful bacteria and concentrate on their mechanisms of resistance to develop successful antimicrobials. Essential oils (EOs) are occur naturally in plants and have long been used as antimicrobials, but most have not been researched. This review explores EOs as alternative antimicrobials, investigating their ability to decrease or inhibit biofilm formation, and assess their ability to contribute to AMR control. Low concentrations of EOs can inhibit Gram-positive and Gram-negative pathogenic bacteria. Some EOs have demonstrated strong anti-biofilm activities. If EOs are successful against biofilm formation, particularly in bacteria developing AMR, they could be incorporated into new antimicrobials. Therefore, there is a need to investigate these EOs' potential, particularly for surface disinfection, and against bacteria from food, clinical and non-clinical environments.
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Affiliation(s)
- Khaled A. El-Tarabily
- Department of Biology, College of Science, United Arab Emirates University, 15551 Al-Ain, United Arab Emirates
- Harry Butler Institute, Murdoch University, Murdoch 6150, Western Australia, Australia
| | - Mohamed T. El-Saadony
- Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Mahmoud Alagawany
- Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Muhammad Arif
- Department of Animal Sciences, College of Agriculture, University of Sargodha, Sargodha, Pakistan
| | - Gaber E. Batiha
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-13, Inada-cho, 080-8555 Obihiro, Hokkaido, Japan
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, AlBeheira, Egypt
| | - Asmaa F. Khafaga
- Department of Pathology, Faculty of Veterinary Medicine, Alexandria University, Edfina 22758, Egypt
| | - Hamada A.M. Elwan
- Department of Animal and Poultry Production, Faculty of Agriculture, Minia University, El-Minya 61519, Egypt
| | - Shaaban S. Elnesr
- Department of Poultry Production, Faculty of Agriculture, Fayoum University, Fayoum 63514, Egypt
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Fungal Biofilms as a Valuable Target for the Discovery of Natural Products That Cope with the Resistance of Medically Important Fungi-Latest Findings. Antibiotics (Basel) 2021; 10:antibiotics10091053. [PMID: 34572635 PMCID: PMC8471798 DOI: 10.3390/antibiotics10091053] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/23/2021] [Accepted: 08/26/2021] [Indexed: 12/18/2022] Open
Abstract
The development of new antifungal agents that target biofilms is an urgent need. Natural products, mainly from the plant kingdom, represent an invaluable source of these entities. The present review provides an update (2017-May 2021) on the available information on essential oils, propolis, extracts from plants, algae, lichens and microorganisms, compounds from different natural sources and nanosystems containing natural products with the capacity to in vitro or in vivo modulate fungal biofilms. The search yielded 42 articles; seven involved essential oils, two Brazilian propolis, six plant extracts and one of each, extracts from lichens and algae/cyanobacteria. Twenty articles deal with the antibiofilm effect of pure natural compounds, with 10 of them including studies of the mechanism of action and five dealing with natural compounds included in nanosystems. Thirty-seven manuscripts evaluated Candida spp. biofilms and two tested Fusarium and Cryptococcus spp. Only one manuscript involved Aspergillus fumigatus. From the data presented here, it is clear that the search of natural products with activity against fungal biofilms has been a highly active area of research in recent years. However, it also reveals the necessity of deepening the studies by (i) evaluating the effect of natural products on biofilms formed by the newly emerged and worrisome health-care associated fungi, C. auris, as well as on other non-albicans Candida spp., Cryptococcus sp. and filamentous fungi; (ii) elucidating the mechanisms of action of the most active natural products; (iii) increasing the in vivo testing.
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