Treatment of implant-associated infection is becoming more challenging,especially when bacterial biofilms form on the surface of the implants.Developing multi-mechanism antibacterial methods to combat bacterial biofil...Treatment of implant-associated infection is becoming more challenging,especially when bacterial biofilms form on the surface of the implants.Developing multi-mechanism antibacterial methods to combat bacterial biofilm infections by the synergistic effects are superior to those based on single modality due to avoiding the adverse effects arising from the latter.In this work,TiO2 nanorod arrays in combination with irradiation with 808 nearinfrared(NIR)light are proven to eradicate single specie biofilms by combining photothermal therapy,photodynamic therapy,and physical killing of bacteria.The TiO2 nanorod arrays possess efficient photothermal conversion ability and produce a small amount of reactive oxygen species(ROS).Physiologically,the combined actions of hyperthermia,ROS,and puncturing by nanorods give rise to excellent antibacterial properties on titanium requiring irradiation for only 15 min as demonstrated by our experiments conducted in vitro and in vivo.More importantly,bone biofilm infection is successfully treated efficiently by the synergistic antibacterial effects and at the same time,the TiO2 nanorod arrays improve the new bone formation around implants.In this protocol,besides the biocompatible TiO2 nanorod arrays,an extra photosensitizer is not needed and no other ions would be released.Our findings reveal a rapid bacteria-killing method based on the multiple synergetic antibacterial modalities with high biosafety that can be implemented in vivo and obviate the need for a second operation.The concept and antibacterial system described here have large clinical potential in orthopedic and dental applications.展开更多
Loureirin A is a major active component of Draconis sanguis, a traditional Chinese medicine. This work aimed to investigate the activity of loureirin A against Candida albicans biofilms. 2, 3-Bis-(2-methoxy-4-nitro-5-...Loureirin A is a major active component of Draconis sanguis, a traditional Chinese medicine. This work aimed to investigate the activity of loureirin A against Candida albicans biofilms. 2, 3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide(XTT) reduction assay and scanning electron microscopy were used to investigate the anti-biofilm effect.Minimal inhibitory concentration testing and time-kill curve assay were used to evaluate fungicidal activity. Cell surface hydrophobicity(CSH) assay and hyphal formation experiment were respectively carried out to investigate adhesion and morphological transition,two virulence traits of C. albicans. Real-time RT-PCR was used to investigate gene expression. Galleria mellonella-C. albicans and Caenorhabditis elegans-C. albicans infection models were used to evaluate the in-vivo antifungal effect. Human umbilical vein endothelial cells and C. elegans nematodes were used to evaluate the toxicity of loureirin A. Our data indicated that loureirin A had a significant effect on inhibiting C. albicans biofilms, decreasing CSH, and suppressing hyphal formation. Consistently, loureirin A down-regulated the expression of some adhesion-related genes and hypha/biofilm-related genes. Moreover, loureirin A prolonged the survival of Galleria mellonella and Caenorhabditis elegans in C. albicans infection models and exhibited low toxicity. Collectively,loureirin A inhibits fungal biofilms, and this effect may be associated with the suppression of pathogenic traits, adhesion and hyphal formation.展开更多
The dramatic increase of microbial resistances against conventional available antibiotics is a huge challenge to the effective treatment of infectious disease and thus becoming a daunting global threat of major concer...The dramatic increase of microbial resistances against conventional available antibiotics is a huge challenge to the effective treatment of infectious disease and thus becoming a daunting global threat of major concern,which necessitates the development of innovative therapeutics.Nanomaterial-based antimicrobial strategies have emerged as novel and promising tools to combat lethal bacteria and recalcitrant biofilm,featuring the abilities to evade existing drug resistance-related mechanisms.In this review,recent advances in“state-of-the-art”nanosystems which acting either as inherent therapeutics or nanocarriers for the precise delivery of antibiotics,are comprehensively summarized.Those nanosystems can effectively accumulate at the infectious sites,achieve multifunctional synergistic antibacterial efficacy,and provide controlled release of antibiotics in response to endogenous or exogenous stimulus(e.g.,low pH,enzymes,or illumination).Especially,the nanoplatform that integrated with photothermal/photodynamic therapy(PTT/PDT)can enhance the bacterial destruction and biofilm penetration or ablation.In addition,nanoparticle-based approaches with enzymatically promoting bacterial killing,anti-virulence,and other mechanisms were also involved.Overall,this review provides crucial insights into the recent progress and remaining limitations of various antimicrobial nanotherapeutic strategies,and enlightens the further developments in this field simultaneously,which eventually benefiting public health.展开更多
Infected wounds pose a significant global health challenge due to the persistence of bacterial biofilms and limited tissue self-repair.Nitric oxide(NO)functions as a potent antimicrobial agent,demonstrating a dual cap...Infected wounds pose a significant global health challenge due to the persistence of bacterial biofilms and limited tissue self-repair.Nitric oxide(NO)functions as a potent antimicrobial agent,demonstrating a dual capacity for both antimicrobial action and tissue rejuvenation across varying concentrations.However,achieving controlled NO release at distinct stages of infected wound progression,simultaneously targeting biofilm removal and wound recovery,remains a formidable challenge.In this work,we introduce a smart electrospun fibrous membrane,featuring an interior laden with NO-loaded HKUST-1 particles and a porous external surface.Notably,the results reveal the photothermal property of HKUST-1 when exposed to near-infrared(NIR)light,enabling precise management of NO release contingent upon light conditions.During the initial phase of infection treatment,a significant NO release is triggered by near-infrared photothermal stimulation,synergistically complementing photothermal therapy to effectively eliminate bacterial biofilms.Subsequently,in the wound-healing phase,NO is released from the degrading fibrous membrane in a controlled and gradual manner,synergizing with trace amounts of copper ions released during MOF degradation.This collaborative mechanism accelerates the formation of blood vessels within the wound,thereby facilitating the healing process.This study suggests a promising and innovative approach for the effective treatment of infected wounds.展开更多
Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative stra...Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative strategy to develop a multifunctional antimicrobial agent with broad-spectrum antibacterial activity by coupling photosensitizers (PSs) with antimicrobial peptides (AMPs). This strategy capitalizes on the ability of PSs to generate reactive oxygen species (ROS) and the membrane-targeting property of AMPs (KRWWKWIRW, a peptide screened by an artificial neural network), synergistically enhancing the antimicrobial activity. In addition, unlike conventional aggregation-caused quenching (ACQ) photosensitizers, aggregation-induced emission (AIE) PSs show stronger fluorescence emission in the aggregated state to help visualize the antibacterial mechanism. In vitro antibacterial experiments demonstrated the excellent killing effects of the developed agent against both Gram-positive (G^(+)) and Gram-negative (G^(–)) bacteria. The bacterial-aggregations induced ability enhanced the photoactivatable antibacterial activity against G^(–) bacteria. Notably, it exhibited a significant effect on destroying MRSA biofilms. Moreover, it also showed remarkable efficacy in treating wound infections in mice in vivo. This multifunctional antimicrobial agent holds significant potential in addressing the challenges posed by bacterial biofilm-associated infections and drug-resistant bacteria.展开更多
Objective:To investigate the anti-biofilm and anti-bacterial activity of Junceella juncea(J.juncea)against biofilm forming pathogenic strains.Methods:Gorgonians were extraeted with methanol and analysed with fourier t...Objective:To investigate the anti-biofilm and anti-bacterial activity of Junceella juncea(J.juncea)against biofilm forming pathogenic strains.Methods:Gorgonians were extraeted with methanol and analysed with fourier transform infrared spectroscopy.Biofilm forming pathogens were identified by Congo red agar supplemented with sucrose.A quantitative spectrophotometric method was used to monitor in vitro biofilm reduction by microtitre plate assay.Anti-bacterial activity of methanolic gorgonian extract(MGE)was carried out by disc diffusion method followed by calculating the percentage of increase with crude methanol(CM).Results:The presence of active functional group was exemplified by FT-IR spectroscopy.Dry,black,crystalline colonies confirm the production of extracellular polymeric substances responsible for biofilm formation in Congo red agar.MGE exhibited potential anti-biofilm activity against all tested bacterial strains.The anti-bacterial activity of methanolic extract was comparably higher in Salmonella typhii followed by Escherichia colt,Vibrio cholerae and Shigella flexneri.The overall percentage of increase was higher by 50.2%to CM.Conclusions:To conclude,anti-biofilm and anti-bacterial efficacy of J.juncea is impressive over biofilm producing pathogens and are good source for novel anti-bacterial compounds.展开更多
The formation of biofilm by pathogenic microorganisms has become a problem in the livestock industry since it is considered a potential source of infection for farm animals while increasing microbial resistance to phy...The formation of biofilm by pathogenic microorganisms has become a problem in the livestock industry since it is considered a potential source of infection for farm animals while increasing microbial resistance to physical and chemical agents. Some plant extracts, such as soluble wheat extract, have been shown to be effective in inhibiting or destroying the biofilm of certain micro-organisms under specific conditions. The objective of this study is to evaluate the capacity of the pathogen to form biofilm on different surfaces used in livestock, as well as to evaluate the anti-biofilm capacity of the soluble wheat extract against <i>S. aureus</i> on these surfaces. The inhibition potential of inhibition or destruction of biofilm was tested in vitro. Wheat extract at a concentration of 0.29 mg/100mL showed anti-biofilm activity on <i>S. aureus</i>, inhibiting its formation, as well as destroying it greatly after a contact time of 24 hours, on those surfaces where the microorganism presents more adhesion capacity.展开更多
Antibacterial protein hydrogels are receiving increasing attention in the aspect of bacteria-infected-wound healing. However, bacterial drug resistance and biofilm infections lead to hard healing of wounds, thus the c...Antibacterial protein hydrogels are receiving increasing attention in the aspect of bacteria-infected-wound healing. However, bacterial drug resistance and biofilm infections lead to hard healing of wounds, thus the construction of biological agents that can overcome these issues is essential. Here, a simple and universal method to construct antibiotic-free protein hydrogel with excellent biocompatibility and superior antibacterial activity against drug-resistant bacteria and biofilms was developed. The green industrial microbicide tetrakis (hydroxymethyl) phosphonium sulfate (THPS) as cross-linking agent can be quickly cross-linked with model protein bovine serum albumin (BSA) to form antibacterial hydrogel through simple mixing without any other initiators, subsequently promoting drug-resistance bacteria-infected wound healing. This simple gelatinization strategy allows at least ten different proteins to form hydrogels (e.g. BSA, human serum albumin (HSA), egg albumin, chymotrypsin, trypsin, lysozyme, transferrin, myohemoglobin, hemoglobin, and phycocyanin) under the same conditions, showing prominent universality. Furthermore, drug-resistance bacteria and biofilm could be efficiently destroyed by the representative BSA hydrogel (B-Hydrogel) with antibacterial activity, overcoming biofilm-induced bacterial resistance. The in vivo study demonstrated that the B-Hydrogel as wound dressing can promote reepithelization to accelerate the healing of methicillin-resistant staphylococcus aureus (MRSA)-infected skin wounds without inducing significant side-effect. This readily accessible antibiotic-free protein-based hydrogel not only opens an avenue to provide a facile, feasible and general gelation strategy, but also exhibits promising application in hospital and community MRSA disinfection and treatment.展开更多
In the oil and gas industry,microbiologically influenced corrosion(MIC) is a major threat to hydrotest,a procedure which is required to certify whether a pipeline can be commissioned.Seawater is frequently used as a h...In the oil and gas industry,microbiologically influenced corrosion(MIC) is a major threat to hydrotest,a procedure which is required to certify whether a pipeline can be commissioned.Seawater is frequently used as a hydrotest fluid.In this bio film prevention lab study,an oilfield biofilm consortium was grown in an enriched artificial seawater anaerobically at 37℃ for 60 days.The combination of 100 ppm(w/w) 2,2-dibromo-3-nitrilopropionamide(DBNPA)+100 nM(180 ppb) Peptide A(a biofilm dispersal agent) led to extra SRB(sulfate reducing bacteria),APB(acid producing bacteria) and GHB(general heterotrophic bacteria) sessile cell count reductions of 0.9-log,0.8-log and 0.6-log,respectively,compared with the outcome obtained by using 100 ppm DBNPA only.The Peptide Aenhancement also led to extra reductions of 44 % in weight loss,43 % in maximum pit depth,and 54 % in corrosion current density.展开更多
Silica-based materials are usually used as delivery systems for antibacterial applications.In rare cases,bactericidal cationic surfactant templated silica composites have been reported as antimicrobial agents.However,...Silica-based materials are usually used as delivery systems for antibacterial applications.In rare cases,bactericidal cationic surfactant templated silica composites have been reported as antimicrobial agents.However,their antibacterial efficacy is limited due to limited control in content and structure.Herein,we report a“dual active templating”strategy in the design of nanostructured silica composites with intrinsic antibacterial performance.This strategy uses cationic and anionic structural directing agents as dual templates,both with active antibacterial property.The cationic-anionic dual active templating strategy further contributes to antibacterial nanocomposites with a spiky surface.With controllable release of dual active antibacterial agents,the spiky nanocomposite displays enhanced anti-microbial and anti-biofilm properties toward Staphylococcus epidermidis.These findings pave a new avenue toward the designed synthesis of novel antibacterial nanocomposites with improved performance for diverse antibacterial applications.展开更多
Chronic wounds are a serious worldwide problem,which are often accompanied by wound infections.In this study,bacterial cellulose(BC)-based composites introduced with tannic acid(TA)and magnesium chloride(BC-TA-Mg)were...Chronic wounds are a serious worldwide problem,which are often accompanied by wound infections.In this study,bacterial cellulose(BC)-based composites introduced with tannic acid(TA)and magnesium chloride(BC-TA-Mg)were fabricated for anti-biofilm activities.The prepared composites’surface properties,mechanical capacity,thermal stability,water absorption and retention property,releasing behavior,anti-biofilm activities and potential cytotoxicity were tested.Results showed that TA and MgCl_(2) particles closely adhered to the nanofibers of BC membranes,thus increasing surface roughness and hydrophobicity of the membranes.While the introduction of TA and MgCl_(2) did not influence the transparency of the membranes,making it beneficial for wound inspection.BC-TA and BC-TA-Mg composites displayed increased tensile strength and elongation at break compared to pure BC.Moreover,BC-TA-Mg exhibited higher water absorption and retention capacity than BC and BC-TA,suitable for the absorption of wound exudates.BC-TA-Mg demonstrated controlled release of TA and good inhibitory effect on both singly cultured Staphylococcus aureus and Pseudomonas aeruginosa biofilm and co-cultured biofilm of S.aureus and P.aeruginosa.Furthermore,the cytotoxicity grade of BC-TA-6Mg membrane was eligible based on standard toxicity classifications.These indicated that BC-TA-Mg is potential to be used as wound dressings combating biofilms in chronic wounds.展开更多
基金the National Natural Science Foundation of China(31700834 and 11632013)Major Projects in Research and Development of Shanxi(Projects of International Cooperation,201803D421090)+2 种基金Fund for Shanxi“1331 Project”Key Innovative Research Team(PY201809)Hong Kong Research Grants Council(RGC)General Research Funds(GRF)(CityU 11205617)Guangdong-Hong Kong Technology Cooperation Funding Scheme(TCFS)GHP/085/18SZ(CityU 9440230).
文摘Treatment of implant-associated infection is becoming more challenging,especially when bacterial biofilms form on the surface of the implants.Developing multi-mechanism antibacterial methods to combat bacterial biofilm infections by the synergistic effects are superior to those based on single modality due to avoiding the adverse effects arising from the latter.In this work,TiO2 nanorod arrays in combination with irradiation with 808 nearinfrared(NIR)light are proven to eradicate single specie biofilms by combining photothermal therapy,photodynamic therapy,and physical killing of bacteria.The TiO2 nanorod arrays possess efficient photothermal conversion ability and produce a small amount of reactive oxygen species(ROS).Physiologically,the combined actions of hyperthermia,ROS,and puncturing by nanorods give rise to excellent antibacterial properties on titanium requiring irradiation for only 15 min as demonstrated by our experiments conducted in vitro and in vivo.More importantly,bone biofilm infection is successfully treated efficiently by the synergistic antibacterial effects and at the same time,the TiO2 nanorod arrays improve the new bone formation around implants.In this protocol,besides the biocompatible TiO2 nanorod arrays,an extra photosensitizer is not needed and no other ions would be released.Our findings reveal a rapid bacteria-killing method based on the multiple synergetic antibacterial modalities with high biosafety that can be implemented in vivo and obviate the need for a second operation.The concept and antibacterial system described here have large clinical potential in orthopedic and dental applications.
基金supported by the National Natural Science Foundation of China(No.81772124)the Shanghai Pujiang Program(No.14PJD001)the National Natural Science Foundation of China(No.NSFC81402823)
文摘Loureirin A is a major active component of Draconis sanguis, a traditional Chinese medicine. This work aimed to investigate the activity of loureirin A against Candida albicans biofilms. 2, 3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide(XTT) reduction assay and scanning electron microscopy were used to investigate the anti-biofilm effect.Minimal inhibitory concentration testing and time-kill curve assay were used to evaluate fungicidal activity. Cell surface hydrophobicity(CSH) assay and hyphal formation experiment were respectively carried out to investigate adhesion and morphological transition,two virulence traits of C. albicans. Real-time RT-PCR was used to investigate gene expression. Galleria mellonella-C. albicans and Caenorhabditis elegans-C. albicans infection models were used to evaluate the in-vivo antifungal effect. Human umbilical vein endothelial cells and C. elegans nematodes were used to evaluate the toxicity of loureirin A. Our data indicated that loureirin A had a significant effect on inhibiting C. albicans biofilms, decreasing CSH, and suppressing hyphal formation. Consistently, loureirin A down-regulated the expression of some adhesion-related genes and hypha/biofilm-related genes. Moreover, loureirin A prolonged the survival of Galleria mellonella and Caenorhabditis elegans in C. albicans infection models and exhibited low toxicity. Collectively,loureirin A inhibits fungal biofilms, and this effect may be associated with the suppression of pathogenic traits, adhesion and hyphal formation.
基金This work was supported by the Natural Science Foundation of China(No.82003673)National Key R&D Program of China(Nos.2019YFC0312101 and 2019YFC0312102).
文摘The dramatic increase of microbial resistances against conventional available antibiotics is a huge challenge to the effective treatment of infectious disease and thus becoming a daunting global threat of major concern,which necessitates the development of innovative therapeutics.Nanomaterial-based antimicrobial strategies have emerged as novel and promising tools to combat lethal bacteria and recalcitrant biofilm,featuring the abilities to evade existing drug resistance-related mechanisms.In this review,recent advances in“state-of-the-art”nanosystems which acting either as inherent therapeutics or nanocarriers for the precise delivery of antibiotics,are comprehensively summarized.Those nanosystems can effectively accumulate at the infectious sites,achieve multifunctional synergistic antibacterial efficacy,and provide controlled release of antibiotics in response to endogenous or exogenous stimulus(e.g.,low pH,enzymes,or illumination).Especially,the nanoplatform that integrated with photothermal/photodynamic therapy(PTT/PDT)can enhance the bacterial destruction and biofilm penetration or ablation.In addition,nanoparticle-based approaches with enzymatically promoting bacterial killing,anti-virulence,and other mechanisms were also involved.Overall,this review provides crucial insights into the recent progress and remaining limitations of various antimicrobial nanotherapeutic strategies,and enlightens the further developments in this field simultaneously,which eventually benefiting public health.
基金supported by the National Natural Science Foundation of China(Grant No.32271386)Zhejiang Engineering Research Center for Tissue Repair Materials(Grant No:WIUCASZZXF21001)+4 种基金Wenzhou Science and Technology Major Project(ZY2022028)Wenzhou Science and Technology Project(Y20220142)the seed grants from the Wenzhou Institute,University of Chinese Academy of Sciences(WIUCASQD2020013,WIUCASQD2021030)the Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure(Grant Nos:SKL-202112SIC,SKL202213SIC)the founding from First Affiliated Hospital of Wenzhou Medical University.
文摘Infected wounds pose a significant global health challenge due to the persistence of bacterial biofilms and limited tissue self-repair.Nitric oxide(NO)functions as a potent antimicrobial agent,demonstrating a dual capacity for both antimicrobial action and tissue rejuvenation across varying concentrations.However,achieving controlled NO release at distinct stages of infected wound progression,simultaneously targeting biofilm removal and wound recovery,remains a formidable challenge.In this work,we introduce a smart electrospun fibrous membrane,featuring an interior laden with NO-loaded HKUST-1 particles and a porous external surface.Notably,the results reveal the photothermal property of HKUST-1 when exposed to near-infrared(NIR)light,enabling precise management of NO release contingent upon light conditions.During the initial phase of infection treatment,a significant NO release is triggered by near-infrared photothermal stimulation,synergistically complementing photothermal therapy to effectively eliminate bacterial biofilms.Subsequently,in the wound-healing phase,NO is released from the degrading fibrous membrane in a controlled and gradual manner,synergizing with trace amounts of copper ions released during MOF degradation.This collaborative mechanism accelerates the formation of blood vessels within the wound,thereby facilitating the healing process.This study suggests a promising and innovative approach for the effective treatment of infected wounds.
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China(grant Nos.82272067,81971678,22107123,and M-0696)Natural Science Foundation of Hunan Province(grant Nos.2022JJ80052,2022JJ40656,20231120077,China)+1 种基金Scientific Research Fund of Hunan Provincial Education Department(22B0009,China)the Central South University Innovation-Driven Research Program(2023CXQD004,China).
文摘Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative strategy to develop a multifunctional antimicrobial agent with broad-spectrum antibacterial activity by coupling photosensitizers (PSs) with antimicrobial peptides (AMPs). This strategy capitalizes on the ability of PSs to generate reactive oxygen species (ROS) and the membrane-targeting property of AMPs (KRWWKWIRW, a peptide screened by an artificial neural network), synergistically enhancing the antimicrobial activity. In addition, unlike conventional aggregation-caused quenching (ACQ) photosensitizers, aggregation-induced emission (AIE) PSs show stronger fluorescence emission in the aggregated state to help visualize the antibacterial mechanism. In vitro antibacterial experiments demonstrated the excellent killing effects of the developed agent against both Gram-positive (G^(+)) and Gram-negative (G^(–)) bacteria. The bacterial-aggregations induced ability enhanced the photoactivatable antibacterial activity against G^(–) bacteria. Notably, it exhibited a significant effect on destroying MRSA biofilms. Moreover, it also showed remarkable efficacy in treating wound infections in mice in vivo. This multifunctional antimicrobial agent holds significant potential in addressing the challenges posed by bacterial biofilm-associated infections and drug-resistant bacteria.
基金Supported by DST-NRDMS,Government of India(grant No.041594/F3/2008/dt.08.12.2010)
文摘Objective:To investigate the anti-biofilm and anti-bacterial activity of Junceella juncea(J.juncea)against biofilm forming pathogenic strains.Methods:Gorgonians were extraeted with methanol and analysed with fourier transform infrared spectroscopy.Biofilm forming pathogens were identified by Congo red agar supplemented with sucrose.A quantitative spectrophotometric method was used to monitor in vitro biofilm reduction by microtitre plate assay.Anti-bacterial activity of methanolic gorgonian extract(MGE)was carried out by disc diffusion method followed by calculating the percentage of increase with crude methanol(CM).Results:The presence of active functional group was exemplified by FT-IR spectroscopy.Dry,black,crystalline colonies confirm the production of extracellular polymeric substances responsible for biofilm formation in Congo red agar.MGE exhibited potential anti-biofilm activity against all tested bacterial strains.The anti-bacterial activity of methanolic extract was comparably higher in Salmonella typhii followed by Escherichia colt,Vibrio cholerae and Shigella flexneri.The overall percentage of increase was higher by 50.2%to CM.Conclusions:To conclude,anti-biofilm and anti-bacterial efficacy of J.juncea is impressive over biofilm producing pathogens and are good source for novel anti-bacterial compounds.
文摘The formation of biofilm by pathogenic microorganisms has become a problem in the livestock industry since it is considered a potential source of infection for farm animals while increasing microbial resistance to physical and chemical agents. Some plant extracts, such as soluble wheat extract, have been shown to be effective in inhibiting or destroying the biofilm of certain micro-organisms under specific conditions. The objective of this study is to evaluate the capacity of the pathogen to form biofilm on different surfaces used in livestock, as well as to evaluate the anti-biofilm capacity of the soluble wheat extract against <i>S. aureus</i> on these surfaces. The inhibition potential of inhibition or destruction of biofilm was tested in vitro. Wheat extract at a concentration of 0.29 mg/100mL showed anti-biofilm activity on <i>S. aureus</i>, inhibiting its formation, as well as destroying it greatly after a contact time of 24 hours, on those surfaces where the microorganism presents more adhesion capacity.
基金Harvard Medical School/Brigham and Women’s Hospital Department of Anesthesiology-Basic Scientist Grant(No.2420 BPA075,W.T.)Center for Nanomedicine Research Fund(No.2019A014810,W.T.)+5 种基金Gillian Reny Stepping Strong Center for Trauma Innovation Breakthrough Innovator Award(No.113548,W.T.)Nanotechnology Foundation(No.2022A002721,W.T.)Farokhzad Family Distinguished Chair Foundation(W.T.)Khoury Innovation Award(No.2020A003219,W.T.)and American Heart Association(AHA)Collaborative Sciences Award(No.2018A004190,W.T.).J.O.was supported by the China Postdoctoral Science Foundation(No.2020M683173).
文摘Antibacterial protein hydrogels are receiving increasing attention in the aspect of bacteria-infected-wound healing. However, bacterial drug resistance and biofilm infections lead to hard healing of wounds, thus the construction of biological agents that can overcome these issues is essential. Here, a simple and universal method to construct antibiotic-free protein hydrogel with excellent biocompatibility and superior antibacterial activity against drug-resistant bacteria and biofilms was developed. The green industrial microbicide tetrakis (hydroxymethyl) phosphonium sulfate (THPS) as cross-linking agent can be quickly cross-linked with model protein bovine serum albumin (BSA) to form antibacterial hydrogel through simple mixing without any other initiators, subsequently promoting drug-resistance bacteria-infected wound healing. This simple gelatinization strategy allows at least ten different proteins to form hydrogels (e.g. BSA, human serum albumin (HSA), egg albumin, chymotrypsin, trypsin, lysozyme, transferrin, myohemoglobin, hemoglobin, and phycocyanin) under the same conditions, showing prominent universality. Furthermore, drug-resistance bacteria and biofilm could be efficiently destroyed by the representative BSA hydrogel (B-Hydrogel) with antibacterial activity, overcoming biofilm-induced bacterial resistance. The in vivo study demonstrated that the B-Hydrogel as wound dressing can promote reepithelization to accelerate the healing of methicillin-resistant staphylococcus aureus (MRSA)-infected skin wounds without inducing significant side-effect. This readily accessible antibiotic-free protein-based hydrogel not only opens an avenue to provide a facile, feasible and general gelation strategy, but also exhibits promising application in hospital and community MRSA disinfection and treatment.
基金financially supported by PTT Exploration and Production, ThailandChinese Society for Corrosion and Protection。
文摘In the oil and gas industry,microbiologically influenced corrosion(MIC) is a major threat to hydrotest,a procedure which is required to certify whether a pipeline can be commissioned.Seawater is frequently used as a hydrotest fluid.In this bio film prevention lab study,an oilfield biofilm consortium was grown in an enriched artificial seawater anaerobically at 37℃ for 60 days.The combination of 100 ppm(w/w) 2,2-dibromo-3-nitrilopropionamide(DBNPA)+100 nM(180 ppb) Peptide A(a biofilm dispersal agent) led to extra SRB(sulfate reducing bacteria),APB(acid producing bacteria) and GHB(general heterotrophic bacteria) sessile cell count reductions of 0.9-log,0.8-log and 0.6-log,respectively,compared with the outcome obtained by using 100 ppm DBNPA only.The Peptide Aenhancement also led to extra reductions of 44 % in weight loss,43 % in maximum pit depth,and 54 % in corrosion current density.
基金Open access funding provided by Shanghai Jiao Tong University
文摘Silica-based materials are usually used as delivery systems for antibacterial applications.In rare cases,bactericidal cationic surfactant templated silica composites have been reported as antimicrobial agents.However,their antibacterial efficacy is limited due to limited control in content and structure.Herein,we report a“dual active templating”strategy in the design of nanostructured silica composites with intrinsic antibacterial performance.This strategy uses cationic and anionic structural directing agents as dual templates,both with active antibacterial property.The cationic-anionic dual active templating strategy further contributes to antibacterial nanocomposites with a spiky surface.With controllable release of dual active antibacterial agents,the spiky nanocomposite displays enhanced anti-microbial and anti-biofilm properties toward Staphylococcus epidermidis.These findings pave a new avenue toward the designed synthesis of novel antibacterial nanocomposites with improved performance for diverse antibacterial applications.
基金supported by the National Natural Science Foundation of China(grant numbers 51973018,51773018,31700829 and 52063030)Fundamental Research Funds for the Central Universities and the Youth Teacher International Exchange&Growth Program(grant number QNXM20210019)+1 种基金Key Research and Development Projects of People’s Liberation Army(grant number BWS17J036)Natural Science Foundation of Jiangxi Province of China(grant number 20192ACB20033).
文摘Chronic wounds are a serious worldwide problem,which are often accompanied by wound infections.In this study,bacterial cellulose(BC)-based composites introduced with tannic acid(TA)and magnesium chloride(BC-TA-Mg)were fabricated for anti-biofilm activities.The prepared composites’surface properties,mechanical capacity,thermal stability,water absorption and retention property,releasing behavior,anti-biofilm activities and potential cytotoxicity were tested.Results showed that TA and MgCl_(2) particles closely adhered to the nanofibers of BC membranes,thus increasing surface roughness and hydrophobicity of the membranes.While the introduction of TA and MgCl_(2) did not influence the transparency of the membranes,making it beneficial for wound inspection.BC-TA and BC-TA-Mg composites displayed increased tensile strength and elongation at break compared to pure BC.Moreover,BC-TA-Mg exhibited higher water absorption and retention capacity than BC and BC-TA,suitable for the absorption of wound exudates.BC-TA-Mg demonstrated controlled release of TA and good inhibitory effect on both singly cultured Staphylococcus aureus and Pseudomonas aeruginosa biofilm and co-cultured biofilm of S.aureus and P.aeruginosa.Furthermore,the cytotoxicity grade of BC-TA-6Mg membrane was eligible based on standard toxicity classifications.These indicated that BC-TA-Mg is potential to be used as wound dressings combating biofilms in chronic wounds.
