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1.
Braz J Microbiol ; 55(3): 2581-2592, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38789905

RESUMO

This study aims to evaluate the antibacterial activity of Lactobacillus acidophilus, alone and in combination with ciprofloxacin, against otitis media-associated bacteria. L. acidophilus cells were isolated from Vitalactic B (VB), a commercially available probiotic product containing two lactobacilli species, L. acidophilus and Lactiplantibacillus (formerly Lactobacillus) plantarum. The pathogenic bacterial samples were provided by Al-Shams Medical Laboratory (Baqubah, Iraq). Bacterial identification and antibiotic susceptibility testing for 16 antibiotics were performed using the VITEK2 system. The minimum inhibitory concentration of ciprofloxacin was also determined. The antimicrobial activity of L. acidophilus VB1 cell-free supernatant (La-CFS) was evaluated alone and in combination with ciprofloxacin using a checkerboard assay. Our data showed significant differences in the synergistic activity when La-CFS was combined with ciprofloxacin, in comparison to the use of each compound alone, against Pseudomonas aeruginosa SM17 and Proteus mirabilis SM42. However, an antagonistic effect was observed for the combination against Staphylococcus aureus SM23 and Klebsiella pneumoniae SM9. L. acidophilus VB1 was shown to significantly co-aggregate with the pathogenic bacteria, and the highest co-aggregation percentage was observed after 24 h of incubation. The anti-biofilm activities of CFS and biosurfactant (BS) of L. acidophilus VB1 were evaluated, and we found that the minimum biofilm inhibitory concentration that inhibits 50% of bacterial biofilm (MBIC50) of La-CFS was significantly lower than MBIC50 of La-BS against the tested pathogenic bacterial species. Lactobacillus acidophilus, isolated from Vitane Vitalactic B capsules, demonstrated promising antibacterial and anti-biofilm activities against otitis media pathogens, highlighting its potential as an effective complementary/alternative therapeutic strategy to control bacterial ear infections.


Assuntos
Antibacterianos , Biofilmes , Ciprofloxacina , Lactobacillus acidophilus , Testes de Sensibilidade Microbiana , Otite Média , Probióticos , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus acidophilus/fisiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antibacterianos/farmacologia , Otite Média/microbiologia , Ciprofloxacina/farmacologia , Probióticos/farmacologia , Humanos , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Bactérias/classificação , Doença Crônica , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Antibiose , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
2.
Pharmaceutics ; 15(5)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37242644

RESUMO

The ability of dermatophytes to live in communities and resist antifungal drugs may explain treatment recurrence, especially in onychomycosis. Therefore, new molecules with reduced toxicity that target dermatophyte biofilms should be investigated. This study evaluated nonyl 3,4-dihydroxybenzoate (nonyl) susceptibility and mechanism of action on planktonic cells and biofilms of T. rubrum and T. mentagrophytes. Metabolic activities, ergosterol, and reactive oxygen species (ROS) were quantified, and the expression of genes encoding ergosterol was determined by real-time PCR. The effects on the biofilm structure were visualized using confocal electron microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). T. rubrum and T. mentagrophytes biofilms were susceptible to nonyl and resistant to fluconazole, griseofulvin (all strains), and terbinafine (two strains). The SEM results revealed that nonyl groups seriously damaged the biofilms, whereas synthetic drugs caused little or no damage and, in some cases, stimulated the development of resistance structures. Confocal microscopy showed a drastic reduction in biofilm thickness, and transmission electron microscopy results indicated that the compound promoted the derangement and formation of pores in the plasma membrane. Biochemical and molecular assays indicated that fungal membrane ergosterol is a nonyl target. These findings show that nonyl 3,4-dihydroxybenzoate is a promising antifungal compound.

3.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469067

RESUMO

Abstract Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.


Resumo Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.

4.
Braz. J. Biol. ; 83: 1-5, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765428

RESUMO

Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.(AU)


Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Linho , Biofilmes/crescimento & desenvolvimento , Pé Diabético
5.
Braz. j. biol ; 83: 1-5, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468851

RESUMO

Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.


Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.


Assuntos
Masculino , Feminino , Humanos , Adulto , Biofilmes/crescimento & desenvolvimento , Linho , Pé Diabético
6.
Braz. j. biol ; 83: e245807, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285613

RESUMO

Abstract Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.


Resumo Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.


Assuntos
Humanos , Pé Diabético/tratamento farmacológico , Linho , Diabetes Mellitus , Staphylococcus aureus , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Biofilmes , Metanol
7.
Antibiotics (Basel) ; 11(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35884220

RESUMO

Acne vulgaris is a multifactorial disease that remains under-explored; up to date it is known that the bacterium Cutibacterium acnes is involved in the disease occurrence, also associated with a microbial dysbiosis. Antibiotics have become a mainstay treatment generating the emergence of antibiotic-resistant bacteria. In addition, there are some reported side effects of alternative treatments, which indicate the need to investigate a different therapeutic approach. Natural products continue to be an excellent option, especially those extracted from actinobacteria, which represent a prominent source of metabolites with a wide range of biological activities, particularly the marine actinobacteria, which have been less studied than their terrestrial counterparts. Therefore, this systematic review aimed to identify and evaluate the potential anti-infective activity of metabolites isolated from marine actinobacteria strains against bacteria related to the development of acne vulgaris disease. It was found that there is a variety of compounds with anti-infective activity against Staphylococcus aureus and Staphylococcus epidermidis, bacteria closely related to acne vulgaris development; nevertheless, there is no report of a compound with antibacterial activity or quorum-sensing inhibition toward C. acnes, which is a surprising result. Since two of the most widely used antibiotics for the treatment of acne targeting C. acnes were obtained from actinobacteria of the genus Streptomyces, this demonstrates a great opportunity to pursue further studies in this field, considering the potential of marine actinobacteria to produce new anti-infective compounds.

8.
Nat Prod Res ; 35(24): 6002-6006, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32975125

RESUMO

Infections associated with biofilms developed by Candida spp. are becoming a great problem due to its resistance against the immune response of the host and the action of antifungal agents. Hence, finding substances that can inhibit the development of biofilms increases the likelihood that these compounds one day can become good antifungals applied in the clinic. The aim of this study was to evaluate the effect of ß-citronellol enantiomers on the biofilm formation by Candida albicans and Candida tropicalis isolated from bloodstream infections. Inhibition was evaluated by reading microplates treated with different concentrations of R-(+)-ß-citronellol, S-(-)-ß-citronellol and amphotericin B, compared to negative control, in spectrophotometer at 590 nm. All tested concentrations of ß-citronellol enantiomers inhibited the biofilm formation of Candida. However, it is still necessary to evaluate the behavior of these isomers on mature biofilms, so that they can become more viable as antifungal therapeutical agents.


Assuntos
Antifúngicos , Candida , Monoterpenos Acíclicos , Antifúngicos/farmacologia , Biofilmes , Candida albicans , Testes de Sensibilidade Microbiana
9.
Int J Nanomedicine ; 13: 1179-1213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29520143

RESUMO

Since the dawn of civilization, it has been understood that pathogenic microorganisms cause infectious conditions in humans, which at times, may prove fatal. Among the different virulent properties of microorganisms is their ability to form biofilms, which has been directly related to the development of chronic infections with increased disease severity. A problem in the elimination of such complex structures (biofilms) is resistance to the drugs that are currently used in clinical practice, and therefore, it becomes imperative to search for new compounds that have anti-biofilm activity. In this context, nanotechnology provides secure platforms for targeted delivery of drugs to treat numerous microbial infections that are caused by biofilms. Among the many applications of such nanotechnology-based drug delivery systems is their ability to enhance the bioactive potential of therapeutic agents. The present study reports the use of important nanoparticles, such as liposomes, microemulsions, cyclodextrins, solid lipid nanoparticles, polymeric nanoparticles, and metallic nanoparticles, in controlling microbial biofilms by targeted drug delivery. Such utilization of these nanosystems has led to a better understanding of their applications and their role in combating biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Humanos , Lipídeos/química , Lipossomos/administração & dosagem , Lipossomos/química , Nanopartículas Metálicas/química , Nanopartículas/administração & dosagem , Nanotecnologia , Polímeros/química
10.
J Biomed Mater Res A ; 105(2): 672-679, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27750384

RESUMO

Bioactive glasses (BGs) are promising materials for bone repair due to their desirable properties such as osteoconductivity, biodegradability, angiogenic potential, and antibacterial activity. Ionic dissolution products from bioactive glasses increase the medium pH inhibiting surrounding bacteria proliferation. The activity of BGs against biofilm formation has been enhanced by incorporating organic antibacterial compounds. The aim of this review was to summarize evidence in literature which assesses the efficacy of antibacterial and anti-biofilm compounds embedded in bioactive glasses to prevent peri-implant infection during bone healing. A PubMed bibliographical research was carried out including articles published in the last 20 years. Most previous studies evaluated antibacterial efficiency in planktonic cultures but did not investigate biofilm inhibition, underestimating biofilm clinical relevance. Multifactorial features such as biocompatibility of embedded compounds, receptor site characteristics, and drug delivery efficiency have been found to influence the bioactive glass capability of acting both as an anti-biofilm agent and as a bone repairing biomaterial. Accordingly, further in vitro and in vivo studies are required to select the most promising anti-biofilm agents which should be incorporated into bioactive glasses to counteract biofilm proliferation, without inducing toxic effects on human cells, and with the added functionality of promoting bone regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 672-679, 2017.


Assuntos
Anti-Infecciosos , Biofilmes/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos , Cerâmica , Materiais Revestidos Biocompatíveis , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Biofilmes/crescimento & desenvolvimento , Substitutos Ósseos/química , Substitutos Ósseos/uso terapêutico , Cerâmica/química , Cerâmica/uso terapêutico , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Humanos
11.
Mater Sci Eng C Mater Biol Appl ; 55: 360-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26117766

RESUMO

Microbial resistance represents a challenge for the scientific community to develop new bioactive compounds. The goal of this research was to evaluate the antimicrobial activity of silver nanoparticles (AgNPs) against a clinical isolate of Streptococcus mutans, antibiofilm activity against mature S. mutans biofilms and the compatibility with human fibroblasts. The antimicrobial activity of AgNPs against the planktonic clinical isolate was size and concentration dependent, with smaller AgNPs having a lower minimum inhibitory concentration. A reduction of 2.3 log in the number of colony-forming units of S. mutans was observed when biofilms grown in a CDC reactor were exposed to 100 ppm of AgNPs of 9.5±1.1 nm. However, AgNPs at high concentrations (>10 ppm) showed a cytotoxic effect upon human dermal fibroblasts. AgNPs effectively inhibited the growth of a planktonic S. mutans clinical isolate and killed established S. mutans biofilms, which suggests that AgNPs could be used for prevention and treatment of dental caries. Further research and development are necessary to translate this technology into therapeutic and preventive strategies.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Nanopartículas/química , Prata/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cárie Dentária/microbiologia , Fibroblastos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Nanopartículas/toxicidade , Prata/química , Streptococcus mutans/isolamento & purificação
12.
Mater Sci Eng C Mater Biol Appl ; 49: 604-611, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25686989

RESUMO

Infections arising from bacterial adhesion and colonization on chronic wounds are a significant healthcare problem. Silver nanoparticles (AgNPs) impregnated in dressing have attracted a great deal of attention as a potential solution. The goal of the present study was to evaluate the anti-biofilm activities of AgNPs impregnated in commercial dressings against Pseudomonas aeruginosa, bacteria isolated of chronic wounds from a hospital patient. The antimicrobial activity of AgNPs was tested within biofilms generated under slow fluid shear conditions using a standard bioreactor. A 2-log reduction in the number of colony-forming units of P. aeruginosa was recorded in the reactor on exposure to dressing impregnated with 250ppm of AgNPs, diameter 9.3±1.1nm, and also showed compatibility to mammalian cells (human fibroblasts). Our study suggests that the use of dressings with AgNPs may either prevent or reduce microbial growth in the wound environment, and reducing wound bioburden may improve wound-healing outcomes.


Assuntos
Biofilmes/efeitos dos fármacos , Nanopartículas/administração & dosagem , Compostos de Prata/farmacologia , Prata/farmacologia , Bandagens , Reatores Biológicos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/microbiologia , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico
13.
Eur J Med Chem ; 82: 127-38, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-24880232

RESUMO

Seven ß-aryl substituted γ-alkylidene-γ-lactones analogues of rubrolides were synthesized from mucobromic acid and converted through a lactamization with isobutylamine into their corresponding γ-hydroxy-γ-lactams (76-85%). These lactams were converted into (Z)- and (E)-γ-alkylidene-γ-lactams (23-45%). All compounds were fully characterized by IR, NMR ((1)H and (13)C), COSY and HETCOR bidimensional experiments, and NOE difference spectroscopy experiments when necessary. Evaluation of these three different classes of compounds against Enterococcus faecalis biofilm formation showed that all classes are active and the highest biofilm inhibition activity was caused by lactam 13f (IC50 = 0.76 µg/mL). Moreover, in almost all cases at least one of the lactams is more active than its correspondent γ-alkylidene-γ-lactone. The use of rubrolides as a lead structure has proven successful for the identification of new compounds displaying novel antibacterial activities, namely biofilm inhibition, which have the potential for the development of antimicrobial drugs targeted to inhibition of the initial stages of bacterial infections, rather than bacterial viability. Such drugs are less prompt to induce bacterial resistance, being therefore a more cost-effective investment for pharmaceutical research.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Lactamas/farmacologia , Lactonas/farmacologia , Antibacterianos/síntese química , Relação Dose-Resposta a Droga , Enterococcus faecalis/crescimento & desenvolvimento , Furanos/química , Lactamas/síntese química , Lactamas/química , Lactonas/síntese química , Lactonas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
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