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Essential Oils (EOs) are currently being researched as potential antibiofilm agents to combat infections related to chronic wound biofilms. As documented in the literature, EOs' in vitro antibacterial properties are often assessed using standard microbiological media and conditions that do not accurately reflect the actual environment of a chronic wound. To address this issue, In vitro Wound Milieu (IVWM) medium, which closely resembles the environment of a chronic wound, was applied for culturing S. aureus biofilms (n = 12) in this research. Biofilms cultivated in the standard Tryptic Soy Broth (TSB) medium served as a control for the experiment. Key biofilm features were analyzed and compared. Subsequently, staphylococci were exposed to the activity of thyme or rosemary EOs (T-EO and R-EO, respectively). As proof of concept, the cytotoxicity of T-EO and its antimicrobial in vivo activity were assessed using a G. mellonella larvae model. Key features of biofilm-forming cells were lower in the IVWM than in the TSB medium: biomass (up to 8 times), metabolic activity (up to 9 times), cell number (up to 100 times), and the live/dead cells ratio. Conversely, biofilm thickness was higher (up to 25%) in IVWM. These differences translated into varied responses of the biofilms to EOs exposure. The application of T-EO led to a greater reduction (up to 2 times) in 67% of biofilm-forming strains in IVWM compared to the TSB medium. Conversely, exposure to R-EO resulted in a higher reduction (up to 2.6 times) of 83% of biofilm-forming strains in TSB than in IVWM. The application of T-EO was not only non-toxic to G. mellonella larvae but also increased the survival of larvae infected with staphylococci (from 48 to 85%). Our findings suggest that EOs not only show promise as agents for treating biofilm-related wound infections but also that providing conditions reflecting the specific niche of the human body is of paramount importance in influencing the results obtained. However, before clinical application, challenges related to the methods of assessing their activity, microbial intra-species variability, and different levels of activity of various EOs should be analyzed and standardized.
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Óleos Voláteis , Humanos , Óleos Voláteis/farmacologia , Staphylococcus aureus/fisiologia , Testes de Sensibilidade Microbiana , Biofilmes , Staphylococcus , Antibacterianos/farmacologiaRESUMO
Credible assessment methods must be applied to evaluate antiseptics' in vitro activity reliably. Studies indicate that the medium for biofilm culturing should resemble the conditions present at the site of infection. We cultured S. aureus, S. epidermidis, P. aeruginosa, C. albicans, and E. coli biofilms in IVWM (In Vitro Wound Milieu)-the medium reflecting wound milieu-and were compared to the ones cultured in the laboratory microbiological Mueller-Hinton (MH) medium. We analyzed and compared crucial biofilm characteristics and treated microbes with polyhexamethylene biguanide hydrochloride (PHMB), povidone-iodine (PVP-I), and super-oxidized solution with hypochlorites (SOHs). Biofilm biomass of S. aureus and S. epidermidis was higher in IVWM than in MH medium. Microbes cultured in IVWM exhibited greater metabolic activity and thickness than in MH medium. Biofilm of the majority of microbial species was more resistant to PHMB and PVP-I in the IVWM than in the MH medium. P. aeruginosa displayed a two-fold lower MBEC value of PHMB in the IVWM than in the MH medium. PHMB was more effective in the IVWM than in the MH medium against S. aureus biofilm cultured on a biocellulose carrier (instead of polystyrene). The applied improvement of the standard in vitro methodology allows us to predict the effects of treatment of non-healing wounds with specific antiseptics.
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Anti-Infecciosos Locais , Anti-Infecciosos Locais/farmacologia , Povidona-Iodo/farmacologia , Staphylococcus aureus , Escherichia coli , Biofilmes , Pseudomonas aeruginosaRESUMO
Chronic wound infection is highly associated with morbidity and endangers the patient's life. Therefore, wound care products must have a potent antimicrobial and biofilm-eradicating effect. In this work, the antimicrobial/antibiofilm activity of two low-concentrated chlorine-based and releasing solutions was investigated on a total of 78 strains of methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, using the cohesive spectrum of in vitro settings, including microtiter plate models, biofilm-oriented antiseptic test, cellulose-based biofilm model, biofilm bioreactors and Bioflux model. The antiseptic containing polyhexamethylene biguanide was used in the character of usability control of performed tests. The results obtained by static biofilm models indicate that low-concentrated chlorine-based and releasing solutions display none to moderate antibiofilm activity, while data obtained by means of the Bioflux model, providing flow conditions, indicate the moderate antibiofilm activity of substances compared with the polyhexanide antiseptic. Considering in vitro data presented in this manuscript, the earlier reported favorable clinical results of low-concentrated hypochlorites should be considered rather an effect of their rinsing activity combined with low cytotoxicity but not the antimicrobial effect per se. For the treatment of heavily biofilm-infected wounds, polyhexanide should be considered the agent of choice because of its higher efficacy against pathogenic biofilms.
Assuntos
Anti-Infecciosos Locais , Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Humanos , Anti-Infecciosos Locais/farmacologia , Ácido Hipocloroso , Cloro , Biofilmes , Pseudomonas aeruginosa , Antibacterianos/uso terapêuticoRESUMO
Staphylococcal biofilms are major causative factors of non-healing wound infections. Their treatment algorithms recommend the use of locally applied antiseptic agents to counteract the spread of infection. The efficacy of antiseptics against biofilm is assessed in vitro by a set of standard quantitative and semi-quantitative methods. The development of software for image processing additionally allowed for the obtainment of quantitative data from microscopic images of biofilm dyed with propidium iodine and SYTO-9 reagents, differentiating dead cells from live ones. In this work, the method of assessment of the impact of antiseptic agents on staphylococcal biofilm in vitro, based on biofilms' processed images, was proposed and scrutinized with regard to clinically relevant antiseptics, polyhexanide, povidone-iodine and hypochlorite. The standard quantitative culturing method was applied to validate the obtained data from processed images. The results indicated significantly higher activity of polyhexanide and povidone-iodine than hypochlorite against staphylococcal biofilm. Taking into account the fact that in vitro results of the efficacy of antiseptic agents against staphylococcal biofilm are frequently applied to back up their use in hospitals and ambulatory units, our work should be considered an important tool; providing reliable, quantitative data in this regard.
Assuntos
Anti-Infecciosos Locais , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Povidona-Iodo/farmacologia , Ácido Hipocloroso , Anti-Infecciosos Locais/farmacologia , Biofilmes , Infecções Estafilocócicas/tratamento farmacológico , Antibacterianos/uso terapêuticoRESUMO
The prevalence of coronary artery disease (CAD) increases every year; however, the impact of microelements on its underlying cause-atherosclerosis-is still unclear. Copper plays numerous regulatory roles in cardiovascular health and was suggested to influence the classic risk factors for CAD. The copper-to-zinc-ratio (Cu/Zn-ratio) reflects systemic oxidative stress-one of the factors in the complex pathogenesis of atherosclerosis. Hair incorporates metal ions during its growth; thus, it reflects the metal exposure that occurred over the last 4-8 weeks. The aim of the presented study was to verify the association between Cu and Cu/Zn-ratio content and the occurrence of acute coronary syndrome (ACS) in the hair of 133 patients who underwent coronary angiography due to suspected ACS. Additionally, association between Cu and Cu/Zn-ratio and selected risk factors for CAD was analyzed. Neither Cu nor Cu/Zn-ratio levels were associated with the occurrence of ACS, regardless of its type (UA/NSTEMI/STEMI). We did not find a significant association between Cu content in hair and risk factors for CAD. The Cu/Zn-ratio in hair was significantly correlated only with body mass index. The relationship of Cu content and Cu/Zn-ratio in hair with CAD, its risk factors and ACS appears to be complex and requires further well-designed research.
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Síndrome Coronariana Aguda , Aterosclerose , Doença da Artéria Coronariana , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/etiologia , Cobre , Cabelo , Humanos , Fatores de Risco , ZincoRESUMO
The biofilm-associated infections of bones are life-threatening diseases, requiring application of dedicated antibiotics in order to counteract the tissue damage and spread of microorganisms. The in vitro analyses on biofilm formation and susceptibility to antibiotics are frequently carried out using methods that do not reflect conditions at the site of infection. To evaluate the influence of nutrient accessibility on Staphylococcus aureus biofilm development in vitro, a cohesive set of analyses in three different compositional media was performed. Next, the efficacy of four antibiotics used in bone infection treatment, including gentamycin, ciprofloxacin, levofloxacin, and vancomycin, against staphylococcal biofilm, was also assessed. The results show a significant reduction in the ability of biofilm to grow in a medium containing elements occurring in the serum, which also translated into the diversified changes in the efficacy of used antibiotics, compared to the setting in which conventional media were applied. The differences indicate the need for implementation of adequate in vitro models that closely mimic the infection site. The results of the present research may be considered an essential step toward the development of in vitro analyses aiming to accurately indicate the most suitable antibiotic to be applied against biofilm-related infections of bones.
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Osteomielite , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Ciprofloxacina , Gentamicinas , Humanos , Levofloxacino/farmacologia , Levofloxacino/uso terapêutico , Testes de Sensibilidade Microbiana , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus , Vancomicina/farmacologia , Vancomicina/uso terapêuticoRESUMO
Atherosclerosis, the underlying cause of coronary artery disease (CAD), has a significant inflammatory component. White blood cell count is an affordable and accessible way to assess the systemic immune response, as it comprises many subgroups with distinct and complex functions. Considering their multidirectional effect on atherosclerosis, new biomarkers integrating various leukocyte subgroups, the Systemic Inflammatory Index (SII) and the Systemic Inflammatory Response Index (SIRI), were recently devised to describe the balance between inflammation and immune reaction. This research aimed to evaluate the relationship of the intensity of inflammation measured by these biomarkers with the severity of CAD assessed with coronary angiography and with the diagnosis of acute coronary syndrome (ACS) or stable CAD in 699 patients. SIRI, but not SII, was associated with the diagnosis, having the highest values for patients with ACS (STEMI), significantly higher than in patients with stable CAD (p < 0.01). The highest SII and SIRI values were observed in patients with three-vessel CAD. SII and SIRI require further in-depth and well-designed research to evaluate their potential in a clinical setting.
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Síndrome Coronariana Aguda , Aterosclerose , Doença da Artéria Coronariana , Aterosclerose/complicações , Biomarcadores , Humanos , Inflamação , Síndrome de Resposta Inflamatória SistêmicaRESUMO
Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Although zinc (Zn) was reported to have antioxidant, anti-inflammatory and protective properties in CVDs, its association with coronary artery disease (CAD) is still unclear. As methods commonly used to assess Zn levels in blood and urine do not show the full picture of the microelement supply, in this study, the nutritional status of Zn in patients with angiographically confirmed CAD was assessed using inductively coupled plasma optical emission spectrometry. We found no association between Zn and the severity of CAD evaluated with the Coronary Artery Surgery Study Score (p = 0.67). There were no statistically significant differences in Zn levels between patients with acute coronary syndrome and those with stable CAD (p = 0.937). A statically significant negative correlation was observed between Zn content and serum triglyceride concentration (p < 0.05). Patients with type 2 diabetes mellitus were found to have a significantly lower hair Zn content compared to non-diabetic individuals (p < 0.01). The role of Zn in the pathogenesis of CAD and its complications need further well-designed research as the moderation and supplementation of Zn dietary intake could be a simple intervention to reduce the CVDs risk.
Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Cabelo , Humanos , Fatores de Risco , ZincoRESUMO
Pseudomonas aeruginosa is an opportunistic pathogen causing life-threatening, hard-to-heal infections associated with the presence of a biofilm. Essential oils (EOs) are promising agents to combat pseudomonal infections because of the alleged antimicrobial activity of their volatile fractions and liquid forms. Therefore, the purpose of this paper was to evaluate the antibacterial efficacy of both volatile and liquid phases of seven EOs (thyme, tea tree, basil, rosemary, eucalyptus, menthol mint, lavender) against P. aeruginosa biofilm and planktonic cells with the use of a broad spectrum of analytical in vitro methods. According to the study results, the antibacterial activity of EOs in their liquid forms varied from that of the volatile fractions. Overall, liquid and volatile forms of rosemary EO and tea tree EO displayed significant antibiofilm effectiveness. The outcomes indicate that these particular EOs possess the potential to be used in the therapy of P. aeruginosa infections.
Assuntos
Óleos Voláteis , Rosmarinus , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Plâncton , Pseudomonas aeruginosa , CháRESUMO
Hernia repairs are the most common abdominal wall elective procedures performed by general surgeons. Hernia-related postoperative infective complications occur with 10% frequency. To counteract the risk of infection emergence, the development of effective, biocompatible and antimicrobial mesh adjuvants is required. Therefore, the aim of our in vitro investigation was to evaluate the suitability of bacterial cellulose (BC) polymer coupled with gentamicin (GM) antibiotic as an absorbent layer of surgical mesh. Our research included the assessment of GM-BC-modified meshes' cytotoxicity against fibroblasts ATCC CCL-1 and a 60-day duration cell colonisation measurement. The obtained results showed no cytotoxic effect of modified meshes. The quantified fibroblast cells levels resembled a bimodal distribution depending on the time of culturing and the type of mesh applied. The measured GM minimal inhibitory concentration was 0.47 µg/mL. Results obtained in the modified disc-diffusion method showed that GM-BC-modified meshes inhibited bacterial growth more effectively than non-coated meshes. The results of our study indicate that BC-modified hernia meshes, fortified with appropriate antimicrobial, may be applied as effective implants in hernia surgery, preventing risk of infection occurrence and providing a high level of biocompatibility with regard to fibroblast cells.
Assuntos
Anti-Infecciosos , Telas Cirúrgicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Celulose/farmacologia , Fibroblastos , Hérnia/tratamento farmacológico , Humanos , Telas Cirúrgicas/microbiologiaRESUMO
In this research we developed a micro-sized hierarchical structures on a poly(l-lactide) (PLLA) surface. The obtained structures consist of round-shaped protrusions with a diameter of ~20 µm, a height of ~3 µm, and the distance between them ~30 µm. We explored the effect of structuring PLLA to design a non-cytotoxic material with increased roughness to encourage cells to settle on the surface. The PLLA films were prepared using the casting melt extrusion technique and were modified using ultra-short pulse irradiation - a femtosecond laser operating at λ = 1030 nm. A hierarchical microstructure was obtained resembling 'cookies on a tray'. The cellular response of fibro- and osteoblasts cell lines was investigated. The conducted research has shown that the laser-modified surface is more conducive to cell adhesion and growth (compared to unmodified surface) to such an extent that allows the formation of highly-selectively patterns consisting of living cells. In contrast to eukaryotic cells, the pathogenic bacteria Staphylococcus aureus covered modified and unmodified structures in an even, non-preferential manner. In turn, adhesion pattern of eukaryotic fungus Saccharomyces boulardii resembled that of fibro- and osteoblast cells rather than that of Staphylococcus. The discovered effect can be used for fabrication of personalized and smart implants in regenerative medicine.
Assuntos
Osteoblastos , Poliésteres , Adesão Celular , Linhagem Celular , Poliésteres/químicaRESUMO
In the era of the coronavirus pandemic, one of the most demanding areas was the supply of healthcare systems in essential Personal Protection Equipment (PPE), including face-shields and hands-free door openers. This need, impossible to fill by traditional manufacturing methods, was met by implementing of such emerging technologies as additive manufacturing (AM/3D printing). In this article, Poly(lactic acid) (PLA) filaments for Fused filament fabrication (FFF) technology in the context of the antibacterial properties of finished products were analyzed. The methodology included 2D radiography and scanning electron microscopy (SEM) analysis to determine the presence of antimicrobial additives in the material and their impact on such hospital pathogens as Staphylococcus aureus, Pseudomonas aeruginosa, and Clostridium difficile. The results show that not all tested materials displayed the expected antimicrobial properties after processing in FFF technology. The results showed that in the case of specific species of bacteria, the FFF samples, produced using the declared antibacterial materials, may even stimulate the microbial growth. The novelty of the results relies on methodological approach exceeding scope of ISO 22196 standard and is based on tests with three different species of bacteria in two types of media simulating common body fluids that can be found on frequently touched, nosocomial surfaces. The data presented in this article is of pivotal meaning taking under consideration the increasing interest in application of such products in the clinical setting.
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Wound infection may occur in acute and chronic wounds, wounds resulting from surgery or traffic accidents, and burns. Regardless of the extent and cause of the wound, prompt treatment is essential in reducing the patient's pain and limiting the spread of contamination. Improper wound care and associated chronic diseases may hinder the therapeutic success. Bacterial cellulose (BC) is highly biocompatible and has no cytotoxic effect on cells engaged in wound healing, such as fibroblasts and keratinocytes. Its high hydration level guarantees the maintenance of a moist wound environment. High mechanical strength, flexibility and resistance to damage make BC a promising material for dressings. Unfortunately, it does not display an inhibitory effect on bacterial growth. Introducing antimicrobial agents into the structure of BC has been a subject of many studies. This paper aims to present the latest reports on the possibility of the absorption of bacteriostatic and bactericidal agents in BC, such as metal particles, essential oils, antibiotics, antiseptics, and wound irrigation solutions. Moreover, the modifications in BC culture and post-production treatments in order to improve its physical properties are discussed.
Assuntos
Anti-Infecciosos , Queimaduras , Antibacterianos , Bandagens , Celulose , HumanosRESUMO
The staphylococcal biofilm-based infections of wounds still pose a significant therapeutical challenge. Treated improperly, they increase the risk of limb amputation or even death of the patient. The present algorithms of infected wound treatment include, among others, the application of antiseptic substances. In vitro wound biofilm models are applied in order to scrutinize their activity. In the present work, using a spectrum of techniques, we showed how the change of a single variable (medium composition) in the standard in vitro model translates not only to shift in staphylococcal biofilm features but also to the change of efficacy of clinically applied wound antimicrobials such as octenidine, polyhexamethylene biguanide, chlorhexidine, hypochlorite solutions, and locally applied gentamycin. The data presented in this study may be of a pivotal nature, taking into consideration the fact that results of in vitro analyses are frequently used to propagate application of specific antimicrobials in hospitals and ambulatory care units.
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Proper protection of vascular access after haemodialysis is one of the key measures for the prevention of catheter-related infections. Various substances with bactericidal and anticoagulant properties are used to fill catheters, but due to the unsatisfactory clinical effects and occurrence of adverse reactions, the search for new substances is still ongoing. In the present paper, we compared the in vitro antimicrobial activity of solutions used for tunnelled catheter locking (taurolidine, trisodium citrate) and solutions of substances that could potentially be used for this purpose (sodium bicarbonate, polyhexanide-betaine). The studies have been conducted on bacteria that most commonly cause catheter-related infections. The values of both minimum inhibitory concentration and minimum biofilm eradication concentration of the substances were determined. The ability of the tested substances to eradicate biofilm from the dialysis catheter surface was also evaluated. The results showed that polyhexanide-betaine inhibited the growth of all microbes comparably to taurolidine, even after ≥ 32-fold dilution. The activity of trisodium citrate and sodium bicarbonate was significantly lower. Polyhexanide exhibited the highest activity in the eradication of bacterial biofilm on polystyrene plates. The biofilm formed on a polyurethane dialysis catheter was resistant to complete eradication by the test substances. Polyhexanide-betaine and taurolidine showed the highest activity. Inhibition of bacterial growth regardless of species was observed not only at the highest concentration of these compounds but also after dilution 32-128x (taurolidine) and 32-1024x (polyhexanide-betaine). Therefore, it can be assumed that taurolidine application as a locking solution prevents catheter colonization and systemic infection development. Taurolidine displays high antimicrobial efficacy against Gram-positive cocci as well as Gram-negative bacilli. On the contrary, the lowest antibacterial effect displayed product contained sodium bicarbonate. The inhibitions of bacterial growth were not satisfactory to consider it as a substance for colonization prevention. Polyhexanidine-betaine possessed potent inhibitory and biofilm eradication properties comparing to all tested products. PHMB is applied as a wound irrigation solution worldwide. However, based on our results, we assume that the PHMB is a promising substance for catheter locking solutions thanks to its safety and high antimicrobial properties.
Assuntos
Anti-Infecciosos Locais/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Relacionadas a Cateter/prevenção & controle , Cateteres Venosos Centrais/microbiologia , Bactérias/patogenicidade , Biofilmes/efeitos dos fármacos , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Cateterismo , Soluções para Hemodiálise/química , Humanos , Diálise Renal/efeitos adversos , Taurina/análogos & derivados , Taurina/farmacologia , Tiadiazinas/farmacologiaRESUMO
The high resistance of staphylococcal biofilm against antibiotics and developing resistance against antiseptics induces a search for novel antimicrobial compounds. Due to acknowledged and/or alleged antimicrobial activity of EOs, their application seems to be a promising direction to follow. Nevertheless, the high complexity of EOs composition and differences in laboratory protocols of the antimicrobial activity assessment hinders the exact estimation of EOs effectiveness. To overcome these disadvantages, in the present work we analysed the effectiveness of volatile and liquid forms of seven EOs (derived from thyme, tea tree, basil, rosemary, eucalyptus, lavender, and menthol mint) against 16 staphylococcal biofilm-forming strains using cohesive set of in vitro techniques, including gas chromatography-mass spectrometry, inverted Petri dish, modified disk-diffusion assay, microdilution techniques, antibiofilm dressing activity measurement, AntiBioVol protocol, fluorescence/confocal microscopy, and dynamic light scattering. Depending on the requirements of the technique, EOs were applied in emulsified or non-emulsified form. The obtained results revealed that application of different in vitro techniques allows us to get a comprehensive set of data and to gain insight into the analysed phenomena. In the course of our investigation, liquid and volatile fractions of thyme EO displayed the highest antibiofilm activity. Liquid fractions of rosemary oil were the second most active against S. aureus. Vapour phases of tea tree and lavender oils exhibited the weakest anti-staphylococcal activity. The size of emulsified droplets was the lowest for T-EO and the highest for L-EO. Bearing in mind the limitations of the in vitro study, results from presented analysis may be of pivotal meaning for the potential application of thymol as a antimicrobial agent used to fight against staphylococcal biofilm-based infections.
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The antimicrobial properties of herbs from Papaveraceae have been used in medicine for centuries. Nevertheless, mutual relationships between the individual bioactive substances contained in these plants remain poorly elucidated. In this work, phytochemical composition of extracts from the aerial and underground parts of five Papaveraceae species (Chelidonium majus L., Corydalis cava (L.) Schweigg. and Körte, C. cheilanthifolia Hemsl., C. pumila (Host) Rchb., and Fumaria vaillantii Loisel.) were examined using LC-ESI-MS/MS with a triple quadrupole analyzer. Large differences in the quality and quantity of all analyzed compounds were observed between species of different genera and also within one genus. Two groups of metabolites predominated in the phytochemical profiles. These were isoquinoline alkaloids and, in smaller amounts, non-phenolic carboxylic acids and phenolic compounds. In aerial and underground parts, 22 and 20 compounds were detected, respectively. These included: seven isoquinoline alkaloids: protopine, allocryptopine, coptisine, berberine, chelidonine, sanguinarine, and chelerythrine; five of their derivatives as well as non-alkaloids: malic acid, trans-aconitic acid, quinic acid, salicylic acid, trans-caffeic acid, p-coumaric acid, chlorogenic acid, quercetin, and kaempferol; and vanillin. The aerial parts were much richer in phenolic compounds regardless of the plant species. Characterized extracts were studied for their antimicrobial potential against planktonic and biofilm-producing cells of S. aureus, P. aeruginosa, and C. albicans. The impact of the extracts on cellular metabolic activity and biofilm biomass production was evaluated. Moreover, the antimicrobial activity of the extracts introduced to the polymeric carrier made of bacterial cellulose was assessed. Extracts of C. cheilanthifolia were found to be the most effective against all tested human pathogens. Multiple regression tests indicated a high antimicrobial impact of quercetin in extracts of aerial parts against planktonic cells of S. aureus, P. aeruginosa, and C. albicans, and no direct correlation between the composition of other bioactive substances and the results of antimicrobial activity were found. Conclusively, further investigations are required to identify the relations between recognized and unrecognized compounds within extracts and their biological properties.
Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Papaveraceae/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/química , Avaliação Pré-Clínica de Medicamentos , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologiaRESUMO
The ongoing search for effective treatment of Acne vulgaris is concentrated, i.a., on natural peptides with antimicrobial properties. The aim of this work was the development of new amino acid derivatives with potential activity on dermal infections against selected microorganisms, including the facultative anaerobe C. acne. The peptides P1-P6 were synthesized via Fmoc solid phase peptide synthesis using Rink amide AM resin, analyzed by RP-HPLC-MS, FTIR, DPPH radical scavenging activity, and evaluated against C. acne and S. aureus, both deposited and non-deposited in BC. Peptides P1-P6 presented a lack of cytotoxicity, antimicrobial activity, or antioxidative properties correlated with selected structural properties. P2 and P4-P6 sorption in BC resulted in variable data, i.a., confirming the prospective topical application of these peptides in a BC carrier.
Assuntos
Acne Vulgar/tratamento farmacológico , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Celulose/metabolismo , Fragmentos de Peptídeos/farmacologia , Propionibacterium acnes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Acne Vulgar/metabolismo , Humanos , Staphylococcus aureus/metabolismoRESUMO
Thermoresponsive hydrogel-based wound dressings with an incorporated antimicrobial agent can be fabricated employing 3D printing technology. A novel printable ink containing poly(N-isopropylacrylamide) (PNIPAAm) precursors, sodium alginate (ALG), methylcellulose (MC) that is laden with a mixture of octenidine dihydrochloride and 2-phenoxyethanol (Octenisept®, OCT) possess accurate printability and shape fidelity. This study also provides the protocol of ink's use for the 3D printing of hydrogel scaffolds. The hydrogel's physicochemical properties and drug release profiles from the hydrogel specimens to the external solution have been determined at two temperatures (20 and 37 °C). The release test showed a sustained OCT delivery into ultrapure water and the PBS solution. The temperature-responsive hydrogel exhibited antimicrobial activity against Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa and demonstrated non-cytotoxicity towards fibroblasts. The thermoresponsive behavior along with biocompatibility, antimicrobial activity, and controlled drug release make this hydrogel a promising class of materials for wound dressing applications.
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Biofilms are surface-attached, structured microbial communities displaying higher tolerance to antimicrobial agents in comparison to planktonic cells. An estimated 80% of all infections are thought to be biofilm-related. The drying pipeline of new antibiotics efficient against biofilm-forming pathogens urges the search for alternative routes of treatment. Essential Oils (EOs), extracted from medicinally important plants, are a reservoir of bioactive compounds that may serve as a foothold in investigating novel antibiofilm compounds. The aim of this study was to compare antimicrobial activity of liquid and volatile fractions of tested EOs against biofilm-forming pathogens using different techniques. In this research, we tested five EOs, extracted from Syzygium aromaticum L., Boswelia serrata Roxb., Juniperus virginiana L., Pelargonium graveolens L. and Melaleuca alternifolia Cheel., against planktonic and biofilm forms of five selected reference strains, namely Staphylococcus aureus, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. To obtain cohesive results, we applied four various methodological approaches: to assess the activity of the liquid fraction of EOs, disc diffusion and the microdilution method were applied; to test EOs' volatile fraction, the AntiBioVol assay and modified Antibiofilm Dressing Activity Measurement (A.D.A.M.) were used. The molecular composition and dynamics of antimicrobial substances released from specific EOs was measured using Gas Chromatography-Mass Spectrometry (GC-MS). The antimicrobial potency of EO's volatile fraction against biofilm formed by tested strains differed from that of the liquid fraction and was related to the molecular weight of volatile compounds. The liquid fraction of CW-EO and volatile fraction of F-EO acted in the strongest manner against biofilm of C. albicans. The addition of 0.5% Tween 20 to liquid phase, enhanced activity of G-EO against E. coli and K. pneumoniae biofilm. EO activity depended on the microbial species it was applied against and the chosen assessment methodology. While all tested EOs have shown a certain level of antimicrobial and antibiofilm effect, our results indicate that the choice of EO to be applied against a specific biofilm-forming pathogen requires careful consideration with regard to the above-listed aspects. Nevertheless, the results presented in this research contribute to the growing body of evidence indicating the beneficial effects of EOs, which may be applied to fight biofilm-forming pathogens.