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Wang S, Zhao Y, Breslawec AP, Liang T, Deng Z, Kuperman LL, Yu Q. Strategy to combat biofilms: a focus on biofilm dispersal enzymes. NPJ Biofilms Microbiomes 2023; 9:63. [PMID: 37679355 PMCID: PMC10485009 DOI: 10.1038/s41522-023-00427-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 08/15/2023] [Indexed: 09/09/2023] Open
Abstract
Bacterial biofilms, which consist of three-dimensional extracellular polymeric substance (EPS), not only function as signaling networks, provide nutritional support, and facilitate surface adhesion, but also serve as a protective shield for the residing bacterial inhabitants against external stress, such as antibiotics, antimicrobials, and host immune responses. Biofilm-associated infections account for 65-80% of all human microbial infections that lead to serious mortality and morbidity. Tremendous effort has been spent to address the problem by developing biofilm-dispersing agents to discharge colonized microbial cells to a more vulnerable planktonic state. Here, we discuss the recent progress of enzymatic eradicating strategies against medical biofilms, with a focus on dispersal mechanisms. Particularly, we review three enzyme classes that have been extensively investigated, namely glycoside hydrolases, proteases, and deoxyribonucleases.
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Affiliation(s)
- Shaochi Wang
- Otorhinolaryngology Hospital, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
- Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Yanteng Zhao
- Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Alexandra P Breslawec
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20740, USA
| | - Tingting Liang
- Key Laboratory of Natural Medicine and Immune-Engineering of Henan Province, Henan University Jinming Campus, 475004, Kaifeng, Henan, China
| | - Zhifen Deng
- Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China
| | - Laura L Kuperman
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20740, USA.
- Mirimus Inc., 760 Parkside Avenue, Brooklyn, NY, 11226, USA.
| | - Qiuning Yu
- Otorhinolaryngology Hospital, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, China.
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Ray RR, Pattnaik S. Contribution of phytoextracts in challenging the biofilms of pathogenic bacteria. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2023. [DOI: 10.1016/j.bcab.2023.102642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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Antibiofilm Activity and Synergistic Effects of Thymol-Loaded Poly (Lactic-Co-Glycolic Acid) Nanoparticles with Amikacin against Four Salmonella enterica Serovars. THE CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY = JOURNAL CANADIEN DES MALADIES INFECTIEUSES ET DE LA MICROBIOLOGIE MEDICALE 2023; 2023:7274309. [PMID: 36698730 PMCID: PMC9870694 DOI: 10.1155/2023/7274309] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 12/02/2022] [Accepted: 12/26/2022] [Indexed: 01/19/2023]
Abstract
Background Salmonella species are frequently linked to biofilm-associated infections. Biofilm formation intensively reduces the efficacy of antibiotics and the host immune system. Therefore, new therapeutic strategies are needed. Thymol, the main monoterpene phenol found in Thymus vulgaris, has been shown to possess potent antibiofilm activity. Our previous findings showed that thymol enhanced the antibiofilm activity of aminoglycosides against Salmonella enterica serovars. However, the clinical potential of thymol has not yet been realized due to its low aqueous solubility and high volatility. Nano-based drug delivery systems have emerged as a novel strategy to resolve these problems. This study aimed to investigate the antibiofilm activity of thymol-loaded poly (lactic-co-glycolic acid) nanoparticles (TH-NPs) and their synergism when used in combination with amikacin antibiotics. Methods The antibacterial activity of TH-NPs was evaluated using the broth microdilution method. Biofilm formation and antibiofilm assays were performed by the miniaturized microtiter plate method. Interaction studies between TH-NPs and amikacin against biofilm were determined using the checkerboard method. Results TH-NPs exhibited antibacterial activity against planktonic cells of S. enterica serovars that were more efficient (8 to 32 times) than free thymol alone. S. Typhimurium and S. Choleraesuis isolates were considered strong biofilm producers. The combination of TH-NPs with amikacin showed synergistic activity in the inhibition and eradication of S. enterica serovar biofilm. The minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC) of amikacin were reduced by 32 to 128-fold when used in combination with TH-NPs. Time-kill kinetic studies showed that the combination of TH-NPs with amikacin possesses bactericidal action. Conclusion This study suggests that the combination of TH-NPs with amikacin can be an alternative to overcome biofilm-associatedSalmonella diseases and therefore should be further explored as a model to search for new antibiofilm drugs.
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Radwan AA, Darwesh OM, Emam MT, Mohamed KA, Shady HMA. A combined treatment of Proteinase K and biosynthesized ZnO-NPs for eradication of dairy biofilm of sporeformers. AIMS Microbiol 2022; 8:507-527. [PMID: 36694584 PMCID: PMC9834087 DOI: 10.3934/microbiol.2022033] [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: 09/11/2022] [Revised: 11/24/2022] [Accepted: 11/30/2022] [Indexed: 12/29/2022] Open
Abstract
Biofilms of sporeformers found in the dairy industry are the major contaminants during processing, as they withstand heat and chemical treatment that are used to control microbes. The present work is aimed to remove these resistant forms of bacterial community (biofilm) present in dairy production lines using ecofriendly agents based on proteinase K (Prot-K) coupled with Zinc oxide nanoparticles (ZnO-NPs). Some metal/metal oxide (Ag, CuO and ZnO) NPs were prepared microbially, and ZnO-NPs were characterized as the most effective ones among them. The produced ZnO-NPs were 15-25 nm in size with spherical shape, and FTIR analysis confirmed the presence of proteins and alkanes surrounding particles as capping agents. Application of Prot-K for eradication (removal) of a model biofilm of mixed sporeformers on food-grade stainless steel resulted in an 83% reduction in the absorbance of crystal violet-stained biofilm. When Prot-K was mixed with the biosynthesized NPs ZnO_G240, the reduction increased to 99.19%. This finding could contribute to an efficient cleaning approach combined with CIP to remove the recalcitrant biofilms in dairy production lines.
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Affiliation(s)
- Ahmed A. Radwan
- Genetics and Cytology Dept., National Research Centre (NRC), Cairo, 12622, Egypt
| | - Osama M. Darwesh
- Agricultural Microbiology Dept., National Research Centre (NRC), Cairo, 12622, Egypt,* Correspondence: , ; Tel: +201155265558
| | - Maha T. Emam
- Genetics and Cytology Dept., National Research Centre (NRC), Cairo, 12622, Egypt
| | - Karima A. Mohamed
- Genetics and Cytology Dept., National Research Centre (NRC), Cairo, 12622, Egypt
| | - Hala M. Abu Shady
- Microbiology Dept., Faculty of Science, Ain-Shams University Cairo, Egypt
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Uddin Mahamud AGMS, Nahar S, Ashrafudoulla M, Park SH, Ha SD. Insights into antibiofilm mechanisms of phytochemicals: Prospects in the food industry. Crit Rev Food Sci Nutr 2022; 64:1736-1763. [PMID: 36066482 DOI: 10.1080/10408398.2022.2119201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The recalcitrance of microbial aggregation or biofilm in the food industry underpins the emerging antimicrobial resistance among foodborne pathogens, exacerbating the phenomena of food spoilage, processing and safety management failure, and the prevalence of foodborne illnesses. The challenges of growing tolerance to current chemical and disinfectant-based antibiofilm strategies have driven the urgency in finding a less vulnerable to bacterial resistance, effective alternative antibiofilm agent. To address these issues, various novel strategies are suggested in current days to combat bacterial biofilm. Among the innovative approaches, phytochemicals have already demonstrated their excellent performance in preventing biofilm formation and bactericidal actions against resident bacteria within biofilms. However, the diverse group of phytochemicals and their different modes of action become a barrier to applying them against specific pathogenic biofilm-formers. This phenomenon mandates the need to elucidate the multi-mechanistic actions of phytochemicals to design an effective novel antibiofilm strategy. Therefore, this review critically illustrates the structure - activity relationship, functional sites of actions, and target molecules of diverse phytochemicals regarding multiple major antibiofilm mechanisms and reversal mechanisms of antimicrobial resistance. The implementation of the in-depth knowledge will hopefully aid future studies for developing phytochemical-based next-generation antimicrobials.
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Affiliation(s)
- A G M Sofi Uddin Mahamud
- School of Food Science and Technology, Chung-Ang University, Anseong-si, Gyeonggi-do, Republic of Korea
| | - Shamsun Nahar
- School of Food Science and Technology, Chung-Ang University, Anseong-si, Gyeonggi-do, Republic of Korea
| | - Md Ashrafudoulla
- School of Food Science and Technology, Chung-Ang University, Anseong-si, Gyeonggi-do, Republic of Korea
| | - Si Hong Park
- Department of Food Science and Technology, Oregon State University, Corvallis, OR, USA
| | - Sang-Do Ha
- School of Food Science and Technology, Chung-Ang University, Anseong-si, Gyeonggi-do, Republic of Korea
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Antibiofilm Synergistic Activity of Streptomycin in Combination with Thymol-Loaded Poly (Lactic-co-glycolic Acid) Nanoparticles against Klebsiella pneumoniae Isolates. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:1936165. [PMID: 35911151 PMCID: PMC9334066 DOI: 10.1155/2022/1936165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/12/2022] [Accepted: 07/01/2022] [Indexed: 11/17/2022]
Abstract
Background. Thymol is an important component of essential oils found in the oil of thyme, is extracted mainly from Thymus vulgaris, and was shown to act synergistically with streptomycin against Klebsiella pneumoniae biofilms. Additionally, thymol could be encapsulated into poly (lactic-co-glycolic acid) (PLGA) nanoparticles to overcome issues related to its low water solubility and high volatility. The present study aimed to investigate the antibiofilm activity of thymol-loaded PLGA nanoparticles (Thy-NPs) alone and in combination with streptomycin against biofilms of K. pneumoniae isolates. Methods. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The antibiofilm activities were determined by the safranin dye assay. The synergistic effect of Thy-NPs with streptomycin was assessed by the checkerboard method. The kinetic study of the biofilm biomass and time-kill assay were further performed. Results. Thy-NPs exhibited the highest antibacterial activity against K. pneumoniae isolates, with MIC values ranging from 1 to 8 µg/mL. Additionally, Thy-NPs showed the highest antibiofilm activity against K. pneumoniae isolates with minimal biofilm inhibitory concentration (MBIC) and minimal biofilm eradication concentration (MBEC) values ranging from 16 to 64 µg/mL and from 32 to 128 µg/Ml, respectively. The combination treatment combining Thy-NPs with streptomycin showed a synergistic effect against the inhibition of biofilm formation and eradication of biofilms of K. pneumoniae isolates with fractional inhibitory concentration index values ranging from 0.13 to 0.28. In addition, the MBIC and MBEC values of streptomycin against K. pneumoniae isolates were dramatically reduced (up to 128-fold) in combination with Thy-NPs, suggesting that Thy-NPs would enhance the antibiofilm activity of streptomycin. The biomass and time-kill kinetics analysis confirmed the observed synergistic interactions and showed the bactericidal activity of streptomycin in combination with Thy-NPs. Conclusions. Our results indicate that the synergistic bactericidal effect between streptomycin and Thy-NPs could be a promising approach in the control of biofilm-associated infections caused by K. pneumoniae.
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Yum SJ, Kwon JH, Lee KT, Park JT, Jeong HG. Efficacy of pristimerin against Staphylococcus aureus planktonic cultures and biofilms. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113627] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Brilhante RSN, Lopes RGP, de Aguiar L, de Oliveira JS, Araújo GDS, Paixão GC, Pereira-Neto WDA, Freire RS, Nunes JVS, de Lima RP, Santos FA, Sidrim JJC, Rocha MFG. Inhibitory effect of proteinase K against dermatophyte biofilms: an alternative for increasing the antifungal effects of terbinafine and griseofulvin. BIOFOULING 2022; 38:286-297. [PMID: 35450473 DOI: 10.1080/08927014.2022.2063720] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
This study aimed to evaluate the effect of proteinase K on mature biofilms of dermatophytes, by assays of metabolic activity and biomass. In addition, the proteinase K-terbinafine and proteinase K-griseofulvin interactions against these biofilms were investigated by the checkerboard assay and scanning electron and confocal microscopy. The biofilms exposed to 32 µg ml-1 of proteinase K had lower metabolic activity and biomass, by 39% and 38%, respectively. Drug interactions were synergistic, with proteinase K reducing the minimum inhibitory concentration of antifungals against dermatophyte biofilms at a concentration of 32 µg ml-1 combined with 128-256 µg ml-1 of terbinafine and griseofulvin. Microscopic images showed a reduction in biofilms exposed to proteinase K, proteinase K-terbinafine and proteinase K-griseofulvin combinations. These findings demonstrate that proteinase K has activity against biofilms of dermatophytes, and the interactions of proteinase K with terbinafine and griseofulvin improve the activity of drugs against mature dermatophyte biofilms.
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Affiliation(s)
- Raimunda Sâmia Nogueira Brilhante
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Raissa Geovanna Pereira Lopes
- Postgraduate Program in Medical Sciences, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Lara de Aguiar
- Postgraduate Program in Veterinary Sciences, College of Veterinary, State University of Ceará, Fortaleza, Ceará, Brazil
| | - Jonathas Sales de Oliveira
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Géssica Dos Santos Araújo
- Postgraduate Program in Veterinary Sciences, College of Veterinary, State University of Ceará, Fortaleza, Ceará, Brazil
| | - Germana Costa Paixão
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Waldemiro de Aquino Pereira-Neto
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Rosemayre Souza Freire
- Analytical Centre, Department of Physics, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - João Victor Serra Nunes
- Analytical Centre, Department of Physics, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Renan Pereira de Lima
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Flávia Almeida Santos
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - José Júlio Costa Sidrim
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Marcos Fábio Gadelha Rocha
- Specialised Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
- Postgraduate Program in Veterinary Sciences, College of Veterinary, State University of Ceará, Fortaleza, Ceará, Brazil
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Fang JY, Chou WL, Lin CF, Sung CT, Alalaiwe A, Yang SC. Facile Biofilm Penetration of Cationic Liposomes Loaded with DNase I/Proteinase K to Eradicate Cutibacterium acnes for Treating Cutaneous and Catheter Infections. Int J Nanomedicine 2021; 16:8121-8138. [PMID: 34938074 PMCID: PMC8687631 DOI: 10.2147/ijn.s335804] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/24/2021] [Indexed: 12/22/2022] Open
Abstract
Background The biofilm produced by Cutibacterium acnes is a major infection threat for skin and implanted catheters. Nanoparticles provide a new approach to eradicate biofilms. The present study evaluated the capability of cationic liposomes loaded with DNase I (DNS) and proteinase K (PK) to remove preformed C. acnes biofilms. Methods DNS and PK were able to target and disassemble the biofilm by degrading extracellular polymer substances (EPS). Soyaethyl morpholinium ethosulfate (SME) was used to render a positive charge and enhance the antibacterial activity of the liposomes. Results The cationic liposomes containing enzymes yielded monodisperse nanovesicles ranging between 95 and 150 nm. The entrapment efficiency of the enzymes in the liposomes achieved a value of 67–83%. All liposomal formulations suppressed planktonic C. acnes growth at a minimum inhibitory concentration (MIC) equal to the free SME in the solution. The enzyme in the liposomal form inhibited biofilm growth much better than that in the free form, with the dual enzyme-loaded liposomes demonstrating the greatest inhibition of 54% based on a crystal violet assay. The biofilm-related virulence genes PA380 and PA1035 were downregulated by the combined enzymes in the liposomes but not the individual DNS or PK. Scanning electron microscopy (SEM) and confocal microscopy displayed reduced C. acnes aggregates and biofilm thickness by the liposomal system. The liposomes could penetrate through about 85% of the biofilm thickness. The in vitro pig skin permeation also showed a facile delivery of liposomes into the epidermis, deeper skin strata, and hair follicles. The liposomes exhibited potent activity to eliminate C. acnes colonization in mouse skin and catheters in vivo. The colony-forming units (CFUs) in the catheter treated with the liposomes were reduced by 2 logs compared to the untreated control. Conclusion The data suggested a safe application of the enzyme-loaded cationic liposomes as antibacterial and antibiofilm agents.
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Affiliation(s)
- Jia-You Fang
- Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan, Taiwan.,Research Center for Food and Cosmetic Safety and Research Center for Chinese Herbal Medicine, Chang Gung University of Science and Technology, Kweishan, Taoyuan, Taiwan.,Department of Anesthesiology, Chang Gung Memorial Hospital, Kweishan, Taoyuan, Taiwan
| | - Wei-Ling Chou
- Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chwan-Fwu Lin
- Research Center for Food and Cosmetic Safety and Research Center for Chinese Herbal Medicine, Chang Gung University of Science and Technology, Kweishan, Taoyuan, Taiwan.,Department of Anesthesiology, Chang Gung Memorial Hospital, Kweishan, Taoyuan, Taiwan.,Department of Cosmetic Science, Chang Gung University of Science and Technology, Kweishan, Taoyuan, Taiwan
| | - Calvin T Sung
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Ahmed Alalaiwe
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al Kharj, Saudi Arabia
| | - Shih-Chun Yang
- Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan, Taiwan.,Department of Cosmetic Science, Providence University, Taichung, Taiwan
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Bisso Ndezo B, Tokam Kuaté CR, Dzoyem JP. Synergistic Antibiofilm Efficacy of Thymol and Piperine in Combination with Three Aminoglycoside Antibiotics against Klebsiella pneumoniae Biofilms. THE CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY = JOURNAL CANADIEN DES MALADIES INFECTIEUSES ET DE LA MICROBIOLOGIE MEDICALE 2021; 2021:7029944. [PMID: 34790281 PMCID: PMC8592759 DOI: 10.1155/2021/7029944] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/14/2021] [Accepted: 10/23/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Thymol and piperine are two naturally occurring bioactive compounds with several pharmacological activities. In this study, their antibiofilm potential either alone or in combination with three aminoglycoside antibiotics was evaluated against a biofilm of Klebsiella pneumoniae. METHODS Determination of antimicrobial susceptibility was performed using the broth microdilution method. Biofilm formation was evaluated by the microtiter plate method. Antibiofilm activity was determined using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium-bromide (MTT) assay. The combination studies were performed by the checkerboard microdilution method. RESULTS The minimum biofilm inhibitory concentration (MBIC) of streptomycin was reduced by 16- to 64-fold when used in combination with thymol, while the MBIC of kanamycin was reduced by 4-fold when combined with piperine. The minimum biofilm eradication concentration (MBEC) values of streptomycin, amikacin, and kanamycin were, respectively, 16- to 128-fold, 4- to 128-fold, and 8- to 256-fold higher than the planktonic minimum inhibitory concentration (MIC). Thymol combined with streptomycin or kanamycin showed synergic effects against the preformed biofilm with 16- to 64-fold reduction in the minimum biofilm eradication concentration values of each antibiotic in combination. Piperine acted also synergically with kanamycin with an 8- to 16-fold reduction in the minimum biofilm eradication concentration values of kanamycin in combination. CONCLUSION The association of thymol with antibiotics showed a strong synergistic effect both in the inhibition of biofilm formation and the destruction of the preformed biofilm of K. pneumoniae. This study suggests that a combination of thymol with streptomycin, amikacin, or kanamycin could be a promising alternative therapy to overcome the problem of K. pneumoniae biofilm-associated infections.
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Affiliation(s)
- Borel Bisso Ndezo
- Laboratory of Microbiology and Antimicrobial Substances, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Christian Ramsès Tokam Kuaté
- Laboratory of Microbiology and Antimicrobial Substances, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Jean Paul Dzoyem
- Laboratory of Microbiology and Antimicrobial Substances, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
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