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1.
Food Chem ; 399: 133962, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007440

RESUMO

Recently, intelligent packaging has emerged for monitoring food quality in food industry. This study aimed to develop the electrospun HACC/PCL/SKN nanofibrous films with improved antimicrobial and antioxidant activity as intelligent packaging to monitor food freshness. The SKN loading resulted in nanoscale uniform fibers (approximately 55.0 nm), and the HACC/PCL/SKN nanofibrous films presented improved hydrophobicity, barrier properties and mechanical properties. Release kinetics study demonstrated that the loading effect led to a sustained release of SKN from fibers. The HACC/PCL film containing 2 wt% SKN showed good antibacterial effect during 24 h, suggesting enhanced antimicrobial activity. Moreover, the SKN-based solutions and films exhibited pH-responsive color changes from red (pH 2) to blue-purple (pH 12). Finally, the HACC/PCL/SKN film effectively provided a spoilage indication for shrimp stored at different temperatures for 3 days by color changes. This work provides a promising strategy for developing multi-functional film as an intelligent packaging in food industry.


Assuntos
Anti-Infecciosos , Quitosana , Nanofibras , Antocianinas/química , Anti-Infecciosos/farmacologia , Quitosana/química , Embalagem de Alimentos/métodos , Concentração de Íons de Hidrogênio , Naftoquinonas , Poliésteres
2.
Braz. j. biol ; 83: e244675, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339348

RESUMO

Abstract Several species of thymus have therapeutic properties, so they are used in traditional medicine. In this work was carried out to synthesize Thymus vulgalis silver nanoparticles (TSNPS) and evaluate antioxidant and antimicrobial activities of TSNPS and T. vulgalis essential oil extract (TEOE). The essential oils analyzed by GC-MS and were characterized. Major compounds of phenol, 2 methyl 5 (1 methylethyle) (CAS), thymol and 1,2 Benzene dicarboxylic acid, 3 nitro (CAS) (48.75%, 32.42% and 8.12%, respectively) were detected. Results demonstrated that the TSNPS gave a highest DPPH radical scavenging activity, it was obtained 97.2 at 1000 ug/ml. TSNPS, Thymus + Hexane (T+H), Thymus + Ethanol (T+E) gave the greatest antimicrobial activity than amoxicillin (AM) and ciprofloxacin (CIP). In conclusion: The essential oil of thymus (Vulgaris) and thymus (Vulgaris) silver nanoparticles can be a good source of natural preservatives as an antioxidant and antimicrobial agents for increasing the shelf life of foodstuffs.


Resumo Diversas espécies de timo possuem propriedades terapêuticas, por isso são utilizadas na medicina tradicional. Neste trabalho foi realizado para sintetizar nanopartículas de prata Thymus vulgalis (TSNPS) e avaliar as atividades antioxidante e antimicrobiana de TSNPS e extrato de óleo essencial de T. vulgalis (TEOE). Os óleos essenciais analisados por GC-MS e foram caracterizados. Os principais compostos de fenol, 2 metil 5 (1 metiletilo) (CAS), timol e ácido 1,2 Benzenodicarboxílico, 3 nitro (CAS) (48,75%, 32,42% e 8,12%, respectivamente) foram detectados. Os resultados demonstraram que o TSNPS deu uma maior atividade de eliminação do radical DPPH , foi obtido 97,2 a 1000 ug / ml. TSNPS, Timo + Hexano (T + H), Timo + Etanol (T + E) deu a maior atividade antimicrobiana do que amoxicilina (AM) e ciprofloxacina (CIP). Em conclusão: O óleo essencial de nanopartículas de prata do timo (Vulgaris) e do timo (Vulgaris) pode ser uma boa fonte de conservantes naturais como agentes antioxidantes e antimicrobianos para aumentar a vida útil de alimentos.


Assuntos
Óleos Voláteis/farmacologia , Thymus (Planta) , Nanopartículas Metálicas , Anti-Infecciosos/farmacologia , Prata , Antioxidantes/farmacologia
3.
Braz. j. biol ; 83: e245753, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278536

RESUMO

Abstract The species Eugenia involucrata DC. is a plant native to Brazil and is traditionally used for intestinal problems, however, little research has documented about its biological potential and phytochemical profile. Thus, the objective of this study was to carry out preliminary phytochemical prospecting, antimicrobial and antioxidant potential of E. involucrata extracts. Using the E. involucrata leaves, aqueous and organic extracts were obtained using the following solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The phytochemical prospecting detected the presence of saponins, steroids, flavonoids and tannins in the extracts. Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans, with concentrations between 3.12 and 50 mg/mL. The ethanolic and metanolic extract presented high free radical sequestration potential (>90%). The methanol extract showed an IC50 value statistically equal to that found for the commercial antioxidant BHT (p <0.05). The crude extracts obtained with ethanol and methanol were the most promising. These results suggest that methanolic, ethanolic and aqueous extracts are a promising source of natural bioactive.


Resumo A espécie Eugenia involucrata DC. é uma planta nativa do Brasil e tradicionalmente utilizada para problemas intestinais, porém, poucas pesquisas documentam sobre seu potencial biológico e perfil fitoquímico. Assim, o objetivo deste trabalho foi realizar uma prospecção fitoquímica preliminar, o potencial antimicrobiano e antioxidante dos extratos de E. involucrata. A partir das folhas de E. involucrata, foram obtidos extratos aquosos e orgânicos com os seguintes solventes (etanol, metanol, hexano, acetona, diclorometano e acetato de etila). A prospecção fitoquímica detectou a presença de saponinas, esteroides, flavonóides e taninos nos extratos. Os extratos etanólico e metanólico apresentaram atividade antimicrobiana para a maioria das cepas bacterianas testadas, assim como para a levedura Candida albicans, com concentrações entre 3,12 e 50 mg/mL. Os extratos etanólico e metanólico apresentaram alto potencial de sequestro de radicais livres (> 90%). O extrato metanólico apresentou IC50 estatisticamente igual ao encontrado para o antioxidante comercial BHT (p <0,05). Os extratos brutos obtidos com etanol e metanol foram os mais promissores. Esses resultados sugerem que os extratos metanólico, etanólico e aquoso são uma fonte promissora de bioativos naturais.


Assuntos
Eugenia , Anti-Infecciosos/farmacologia , Brasil , Extratos Vegetais/farmacologia , Folhas de Planta , Compostos Fitoquímicos , Antioxidantes/farmacologia
4.
Acta Crystallogr C Struct Chem ; 78(Pt 9): 493-506, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36063377

RESUMO

The novel compound N-(2-hydroxy-5-methylphenyl)-2,3-dimethoxybenzamide, C16H17NO4, I, was prepared by a two-step reaction and then characterized by elemental analysis and X-ray diffraction (XRD) methods. Moreover, its spectroscopic properties were investigated by FT-IR and 1H and 13C NMR. Compound I crystallized in the monoclinic space group P21/c and the molecular geometry is not planar, being divided into three planar regions. Supramolecular structures are formed by connecting units via hydrogen bonds. The ground-state molecular structure of I was optimized by the DFT-B3LYP/6-31G(d,p) method and the theoretical structure was compared with that obtained by X-ray diffraction. Intermolecular interactions in the crystal network were studied by two-dimensional (2D) and three-dimensional (3D) Hirshfeld analyses. The calculated electronic transition results were examined and the molecular electrostatic potentials (MEPs) were also determined. The in vitro antimicrobial activities of I against three Gram-positive bacteria, three Gram-negative bacteria and two fungi were determined. The compound was compared with several control drugs and showed better activity than the amoxicillin standard against Gram-positive bacteria B. subtilis, S. aureus and E. faecalis, and Gram-negative bacteria E. coli, K. pneumoniae and P. aeruginosa. The density functional theory (DFT)-optimized structure of the small molecule was used to perform molecular docking studies with proteins from experimentally studied bacterial and fungal organisms using AutoDock to determine the most preferred binding mode of the ligand within the protein cavity. A druglikeness assay and ADME (absorption, distribution, metabolism and excretion) and toxicology studies were carried out and predict a good drug-like character.


Assuntos
Anti-Infecciosos , Proteínas de Escherichia coli , Anti-Infecciosos/farmacologia , Bactérias , Cristalografia por Raios X , Cisteína Endopeptidases , Escherichia coli , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus
5.
Biomed Res Int ; 2022: 9048245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060142

RESUMO

Challenges encountered in relapse of illness caused by resistance of microorganisms to antimicrobial agents (drugs) are due to factors of severe stress initiated by random use of antibiotics and insufficient beneficial approaches. These challenges have resulted to multiple drug resistance (MDR) and, subsequently, biofilm formation. A type of intercellular communication signal called quorum sensing (QS) has been studied to cause the spread of resistance, thereby enabling a formation of stable community for microorganisms. The QS could be inhibited using QS inhibitors (QSIs) called quorum-quenching (QQ). The QQ is an antibiofilm agent. Indole derivatives from plant sources can serve as quorum-quenching eradication approach for biofilm, as well as a promising nontoxic antibiofilm agent. In other words, phytochemicals in plants help to control and prevent biofilm formation. It could be recommended that combination strategies of these indoles' derivatives with antibiotics would yield enhanced results.


Assuntos
Anti-Infecciosos , Percepção de Quorum , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Indóis/farmacologia
6.
Drug Des Devel Ther ; 16: 2817-2832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046334

RESUMO

Introduction: Antibiotic resistance is a global threat that has been increasing recently, especially with antibiotic overuse and misuse. The search for new antibiotics is becoming more and more indispensable. Methods: Design and synthesis of isatin derivatives as surrogates of SB-239629, a bacterial tyrosine-tRNA synthetases (TyrRS) inhibitor. The newly synthesized compounds were screened for their antimicrobial and antibiofilm activities. Docking studies were used to investigate potential binding modes of these compounds with TyrRS. Results and Discussion: Newly synthesized isatin-decorated thiazole derivatives (7b, 7d, and 14b) have shown potent antimicrobial activities against E. coli, a representative of gram-negative bacteria. Also, 7f showed the best activity against Methicillin Resistant Staphylococcus aureus (MRSA). In addition, 7h and 11f were found to have antifungal activities against Candida albicans equivalent to that of the reference Nystatin. All the new isatin derivatives with antimicrobial activities were found to exhibit strong biofilm distortion effects at half their minimum inhibitory concentrations (MIC). Moreover, thiazole derivatives 11a-f showed promising biofilm formation inhibition. Finally, molecular docking studies were used to investigate possible binding modes of target compounds with S. aureus and E. coli TyrRS. Conclusion: The novel isatin-decorated thiazole derivatives show strong antimicrobial and antifungal activities with potential action on TyrRS.


Assuntos
Anti-Infecciosos , Isatina , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Biofilmes , Escherichia coli/metabolismo , Isatina/química , Isatina/farmacologia , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Staphylococcus aureus , Tiazóis/química
7.
Molecules ; 27(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36080366

RESUMO

This study was performed to investigate the effects of different supplemental light spectra and doses (duration and illuminance) on the essential oil of basil (Ocimum basilicum L.) cultivated in the net-house in Vietnam during four months. Ten samples of basil aerial parts were hydrodistilled to obtain essential oils which had the average yields from 0.88 to 1.30% (v/w, dry). The oils analyzed using GC-FID and GC-MS showed that the main component was methyl chavicol (87.4-90.6%) with the highest values found in the oils of basil under lighting conditions of 6 h/day and 150-200 µmol·m-2·s-1. Additional lighting conditions caused the significant differences (p < 0.001) in basil biomass and oil production with the highest values found in the oils of basil under two conditions of (1) 71% Red: 20% Blue: 9.0% UVA in at 120 µmol·m-2·s-1 in 6 h/day and (2) 43.5% Red: 43.5% Blue: 8.0% Green: 5.0% Far-Red at 100 µmol·m-2·s-1 in 6 h/day. The oils of basil in some formulas showed weak inhibitory effects on only the Bacillus subtilis strain. Different light spectra affect the biomass and essential oil production of basil, as well as the concentrations of the major components in the oil.


Assuntos
Anti-Infecciosos , Ocimum basilicum , Óleos Voláteis , Anti-Infecciosos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia
8.
Molecules ; 27(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36080413

RESUMO

Azo molecules, characterized by the presence of a -N=N- double bond, are widely used in various fields due to their sensitivity to external stimuli, ch as light. The emergence of bacterial resistance has pushed research towards designing new antimicrobial molecules that are more efficient than those currently in use. Many authors have attempted to exploit the antimicrobial activity of azobenzene and to utilize their photoisomerization for selective control of the bioactivities of antimicrobial molecules, which is necessary for antibacterial therapy. This review will provide a systematic and consequential approach to coupling azobenzene moiety with active antimicrobial molecules and drugs, including small and large organic molecules, such as peptides. A selection of significant cutting-edge articles collected in recent years has been discussed, based on the structural pattern and antimicrobial performance, focusing especially on the photoactivity of azobenzene and the design of smart materials as the most targeted and desirable application.


Assuntos
Anti-Infecciosos , Compostos Azo , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Compostos Azo/química , Compostos Azo/farmacologia
9.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080486

RESUMO

Pelargonium graveolens leaves are widely used in traditional medicine for relieving some cardiovascular, dental, gastrointestinal, and respiratory disorders. They are also used as food and tea additives in Palestine and many other countries. Consequently, this investigation aimed to describe the chemical markers, cytotoxic, antioxidant, antimicrobial, metabolic, and cyclooxygenase (COX) enzymes inhibitory characteristics of P. graveolens essential oil (PGEO) from Palestine utilizing reference methods. There were 70 chemicals found in the GCMS analysis, and oxygenated terpenoids were the most abundant group of the total PGEO. Citronellol (24.44%), citronellyl formate (15.63%), γ-eudesmol (7.60%), and iso-menthone (7.66%) were the dominant chemical markers. The EO displayed strong antioxidant activity (IC50 = 3.88 ± 0.45 µg/mL) and weak lipase and α-amylase suppressant effects. Notably, the PGEO displayed high α-glucosidase inhibitory efficacy compared with Acarbose, with IC50 doses of 52.44 ± 0.29 and 37.15 ± 0.33 µg/mL, respectively. PGEO remarkably repressed the growth of methicillin-resistant Staphylococcus aureus (MRSA), even more than Ampicillin and Ciprofloxacin, and strongly inhibited Candida albicans compared with Fluconazole. The highest cytotoxic effect of the PGEO was noticed against MCF-7, followed by Hep3B and HeLa cancer cells, with IC50 doses of 32.71 ± 1.25, 40.71 ± 1.89, and 315.19 ± 20.5 µg/mL, respectively, compared with doxorubicin. Moreover, the screened EO demonstrated selective inhibitory activity against COX-1 (IC50 = 14.03 µg/mL). Additionally, PGEO showed a weak suppressant effect on COX-2 (IC50 = 275.97 µg/mL). The current research can be considered the most comprehensive investigation of the chemical and pharmacological characterization of the PGEO. The results obtained in this study demonstrate, without doubt, that this plant represents a rich source of bioactive substances that can be further investigated and authenticated for their medicinal potential.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Óleos Voláteis , Pelargonium , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Pelargonium/química
10.
Arch Microbiol ; 204(10): 620, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100763

RESUMO

The biogenic method for synthesis of nanoparticles is preferred over the traditional strategies, on account of its ease, environmental friendliness, and cost-effectivity, wherein fungi endorse themselves to be the most appropriate precursor for the same. In recent times numerous metal nanoparticles have been reported to exhibit significant therapeutic activities, out of which Zinc Oxide nanoparticles (ZnO NPs) stand apart on account of their multidimensional nature. Thus, this study was carried out with an aim to biosynthesize ZnO NPs utilizing endophyte Trichoderma viride, isolated from the seeds of Momordica charantia. The physicochemical characterization of NPs was done via employing a combination of spectroscopic and microscopic techniques. The NPs were found to have a hexagonal shape and possessed an average particle size of around 63.3 nm. The antimicrobial activity of NPs was evaluated against multi-drug resistant organisms and it was observed to be an appreciable one whereas the antioxidant activity was deduced to be dose-dependent. Thus, these ZnO NPs can be considered as a probable active ingredient of any future therapeutic conceptualization after undertaking a thorough toxicological assessment.


Assuntos
Anti-Infecciosos , Hypocreales , Nanopartículas Metálicas , Óxido de Zinco , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Endófitos , Nanopartículas Metálicas/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia
11.
Arch Microbiol ; 204(9): 589, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36053379

RESUMO

Antibiotic resistance, which has increased rapidly in recent years because of uncontrolled and unconscious antibiotic consumption, poses a major threat to public health. The inadequacy of existing antibiotics has increased the need for new, effective, and less toxic antibiotic raw materials or antibiotic derivatives. Pecan (Carya illinoinensis) and Chestnut (Castanea sativa) flowers possess abundant pollen contents and exhibit similar morphological features. The purpose of this study was to compare these two flower extracts in terms of their antimicrobial and antioxidant activities. Total phenolic content, total flavonoid contents, and phenolic components were also analyzed in aquatic and ethanolic extracts. Antioxidant activities were measured using ferric reducing/antioxidant capacity (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. Antimicrobial and antifungal activities were compared by means of agar diffusion tests against bacteria including Staphylococcus aureus, Bacillus cereus, Mycobacterium smegmatis, Acinetobacter haemolyticus, and Chromobacterium violaceum, and the yeasts Candida albicans and Candida parapsilosis. Anti-quorum sensing (anti-QS), anti-biofilm, and anti-swarming (SW) activities were also studied against Chromobacterium violaceum ATCC 31532, Chromobacterium violaceum ATCC 12472, and Pseudomonas aeruginosa PA01, respectively. Both extracts were rich in ellagic acid and gallic acid and exhibited similar antioxidant properties. Both flower extracts exhibited high antimicrobial and antifungal activities as well as anti-biofilm, anti-QS, and anti-SW activities.


Assuntos
Anti-Infecciosos , Carya , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Biofilmes , Chromobacterium , Flores , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa
12.
Br J Nurs ; 31(16): 838-843, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36094030

RESUMO

Patients in intensive care units (ICUs) are at a greater risk of developing hospital-acquired infections (HCAIs). Decontamination, which usually includes a regimen of body washing with an antimicrobial skin cleanser, is used to prevent HCAIs. Approaches can be: targeted, where carriers are identified and decontaminated; or universal, where all patients undergo a decontamination regimen. Universal rather than targeted decontamination is more effective at reducing infection rates and is more cost-effective. Decontamination in the ICU can lower HCAI rates across the entire hospital. Microbial resistance to chlorhexidine, however, which is the main active agent used for decontamination is increasing, and there are also adverse effects, leading to interest in octenidine as an alternative. This article explores the use of octenidine-containing single-use wash mitts in ICUs, which have been positively evaluated regarding antimicrobial activity, and ease and effectiveness of use.


Assuntos
Anti-Infecciosos , Infecção Hospitalar , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Cuidados Críticos , Infecção Hospitalar/prevenção & controle , Humanos , Iminas , Piridinas
13.
PLoS One ; 17(9): e0272806, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36054112

RESUMO

Surface waters, especially those receiving wastewater flows, can disseminate antimicrobial resistant bacteria (ARB), antimicrobial resistance genes (ARG), and antibiotics. In the Scioto River of central Ohio, United States, we evaluated fishes as potential sentinels of ARB and antimicrobial contamination and investigated the influence of antimicrobial exposure on the fish intestinal resistome. Seventy-seven fish were collected from river reaches receiving inputs from two wastewater treatment plants that serve the greater Columbus Metropolitan Area. Fish were screened for the presence of cephalosporin-resistant (CeRO) and carbapenem-resistant (CRO) organisms, epidemic carbapenemase genes, and antibiotic drugs and metabolites using culture methods, droplet digital PCR, and ultra-high performance liquid chromatography tandem mass spectroscopy (UHPLC-MS/MS). Nearly 21% of fish harbored a CeRO in their resistome, with 19.4% exhibiting bacteria expressing an AmpC genotype encoded by blaCMY, and 7.7% with bacteria expressing an extended-spectrum ß-lactamase phenotype encoded by blaCTX-M. blaKPC and blaNDM were present in 87.7% (57/65) and 80.4% (37/46) of the intestinal samples at an average abundance of 104 copies. Three antibiotics-lincomycin (19.5%), azithromycin (31.2%) and sulfamethoxazole (3.9%)-were found in hepatic samples at average concentrations between 25-31 ng/g. Fish harboring blaCTX-M and those exposed to azithromycin were at greater odds of being downstream of a wastewater treatment plant. Fish that bioconcentrated antibiotics in their liver were not at greater odds of harboring CeRO, CRO, or epidemic carbapenemase gene copies in their resistome. Our findings confirm that fishes can be effective bioindicators of surface waters contaminated with ARB, ARG, and antibiotics. Moreover, our findings highlight the varying importance of different mechanisms that facilitate establishment of ARB in aquatic ecosystems.


Assuntos
Antibacterianos , Anti-Infecciosos , Antagonistas de Receptores de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Azitromicina/farmacologia , Bactérias/genética , Proteínas de Bactérias , Cefalosporinas/farmacologia , Ecossistema , Peixes/genética , Espectrometria de Massas em Tandem , Águas Residuárias/microbiologia , Água/farmacologia , beta-Lactamases/genética , beta-Lactamases/farmacologia
14.
PLoS One ; 17(9): e0274815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112657

RESUMO

The absence of novel antibiotics for drug-resistant and biofilm-associated infections is a global public health crisis. Antimicrobial peptides explored to address this need have encountered significant development challenges associated with size, toxicity, safety profile, and pharmacokinetics. We designed PLG0206, an engineered antimicrobial peptide, to address these limitations. PLG0206 has broad-spectrum activity against >1,200 multidrug-resistant (MDR) ESKAPEE clinical isolates, is rapidly bactericidal, and displays potent anti-biofilm activity against diverse MDR pathogens. PLG0206 displays activity in diverse animal infection models following both systemic (urinary tract infection) and local (prosthetic joint infection) administration. These findings support continuing clinical development of PLG0206 and validate use of rational design for peptide therapeutics to overcome limitations associated with difficult-to-drug pharmaceutical targets.


Assuntos
Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Biofilmes , Preparações Farmacêuticas
15.
Front Cell Infect Microbiol ; 12: 1010625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118027

RESUMO

Proteus mirabilis is a common causative agent for catheter-associated urinary tract infections (CAUTI). The crystalline biofilm formation by P. mirabilis causes catheter encrustation and blockage leading to antibiotic treatment resistance. Thus, biofilm formation inhibition on catheters becomes a promising alternative for conventional antimicrobial-based treatment that is associated with rapid resistance development. Our previous work has demonstrated the in vitro antibiofilm activity of microbial indole derivatives against clinical isolates of P. mirabilis. Accordingly, we aim to evaluate the capacity of silicone Foley catheters (SFC) impregnated with these indole derivatives to resist biofilm formation by P. mirabilis both phenotypically and on the gene expression level. Silicon Foley catheter was impregnated with indole extract recovered from the supernatant of the rhizobacterium Enterobacter sp. Zch127 and the antibiofilm activity was determined against P. mirabilis (ATCC 12435) and clinical isolate P8 cultured in artificial urine. The indole extract at sub-minimum inhibitory concentration (sub-MIC=0.5X MIC) caused a reduction in biofilm formation as exhibited by a 60-70% reduction in biomass and three log10 in adhered bacteria. Results were confirmed by visualization by scanning electron microscope. Moreover, changes in the relative gene expression of the virulence genes confirmed the antibiofilm activity of the indole extract against P. mirabilis. Differential gene expression analysis showed that extract Zch127 at its sub-MIC concentration significantly down-regulated genes associated with swarming activity: umoC, flhC, flhD, flhDC, and mrpA (p< 0.001). In addition, Zch127 extract significantly down-regulated genes associated with polyamine synthesis: speB and glnA (p< 0.001), as well as the luxS gene associated with quorum sensing. Regulatory genes for capsular polysaccharide formation; rcsB and rcsD were not significantly affected by the presence of the indole derivatives. Furthermore, the impregnated catheters and the indole extract showed minimal or no cytotoxic effect against human fibroblast cell lines indicating the safety of this intervention. Thus, the indole-impregnated catheter is proposed to act as a suitable and safe strategy for reducing P. mirabilis CAUTIs.


Assuntos
Anti-Infecciosos , Proteus mirabilis , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Cateteres , Humanos , Indóis/farmacologia , Poliaminas/farmacologia , Polissacarídeos/farmacologia , Silício/farmacologia , Silicones/farmacologia
16.
Arch Microbiol ; 204(9): 584, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048277

RESUMO

A tannase-positive Bacillus gottheilii M2S2 and Bacillus cereus M1GT were co-cultivated for the production of gallic acid using tannic acid as the sole carbon source through submerged fermentation. Taguchi orthogonal array of design of experimental methodology was used to estimate the influence and significance of tannic acid concentration, glucose concentration, agitation speed, and inoculum size on the gallic acid production in a shake flask. Among all the factors, agitation speed contributed the highest for gallic acid production (28.28%), followed by glucose concentration (21.59%), inoculum size (19.6%), tannic acid concentration (19.54%), and pH (11.09%). Validation experiments were executed at the found optimized conditions which resulted in a 6.36-fold increase in gallic acid yield compared to unoptimized conditions. Further, the kinetics of growth, tannic acid degradation, and gallic acid yield were evaluated at the optimized conditions. The kinetic parameters Y x/s, Y p/s, and Y p/x were determined as 0.292 mg of cells/mg of tannic acid, 22.2 µg of gallic acid/mg of tannic acid, and 70.76 µg of gallic acid/mg of cells with a growth rate of 0.273 h -1 after 24 h of fermentation. Finally, the antimicrobial activity of the product gallic acid was investigated against food-borne pathogenic E. coli, S. aureus, and Serriatia marcescens and showed a zone of inhibition of 2 cm, 1.6 cm, and 1.3 cm, respectively, using the agar disc diffusion technique. Thus, the cost-effective bioproduct gallic acid proved to be potentially effective to control food poisoning diseases and preserve foodstuff.


Assuntos
Anti-Infecciosos , Ácido Gálico , Anti-Infecciosos/farmacologia , Técnicas de Cocultura , Escherichia coli/metabolismo , Fermentação , Ácido Gálico/metabolismo , Ácido Gálico/farmacologia , Glucose , Cinética , Staphylococcus aureus/metabolismo , Taninos/metabolismo , Taninos/farmacologia
17.
Pak J Biol Sci ; 25(9): 796-802, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36098081

RESUMO

<b>Background and Objective:</b> Preservation using antimicrobials has been observed to inhibit the growth of pathogenic bacteria in food. Nowadays many people choose food preservatives that are safe for health and natural. Bacteriocins as food preservatives are safe because antimicrobials from the antimicrobial peptide group include GRAS (Generally Recognized As Safe). Bacteriocin-producing LAB can be found in various fermented foods, one of which is "Dadih". Bacteriocins are expected to inhibit the growth of pathogenic bacteria so that they can be developed as an alternative to food preservatives. <b>Materials and Methods:</b> In this study, all experiments were performed with two replicates and the results were expressed as Mean±Standard Deviation (SD). <b>Results:</b> Screening results showed that the DK8 isolate had the highest antimicrobial activity. The DK8 isolate was identified molecularly using 16s RNA sequencing, showing that the DK8 isolate had the highest similarity to <i>Lactobacillus pentosus</i> strain 124-2. Bacteriocins from DK8 isolate and partially purified using ammonium sulfate precipitation at concentrations of 50, 60 and 70%. The addition of ammonium sulfate with a concentration of 50% showed the highest antimicrobial activity against <i>Salmonella</i> sp. (12.63 mm) and <i>Escherichia coli</i> (11.33 mm) while the highest antimicrobial activity against <i>Staphylococcus aureus</i> was the addition of 60% ammonium sulfate (8.13 mm). <b>Conclusion:</b> Lactic acid bacteria isolate was identified to have the highest similarity with <i>Lactobacillus pentosus</i> strain 124-2 and precipitation using 50% ammonium sulfate showed the highest antimicrobial activity.


Assuntos
Anti-Infecciosos , Bacteriocinas , Lactobacillus pentosus , Sulfato de Amônio , Anti-Infecciosos/farmacologia , Bacteriocinas/farmacologia , Escherichia coli , Conservantes de Alimentos/farmacologia , Humanos
18.
J Med Microbiol ; 71(9)2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36099168

RESUMO

Introduction. Plants have been used as medicines for centuries to treat human diseases. Studies with plants are extremely important for the development of future drugs that can benefit the human population.Hypothesis/Gap Statement. With the emergence of pathogens resistant to antimicrobial agents, there is an urgent need to direct research towards the discovery of new antimicrobials.Aim. In this study, Spondias purpurea L. (Anacardiaceae) was evaluated for its antimicrobial activity, antioxidant activity and cytotoxicity.Methodology. Antimicrobial activity was evaluated by the MIC using the 96-well plate microdilution technique of ethanolic, hexanic and dicloromethanic extracts of dried S. purpurea leaves against bacteria, yeast and filamentous fungi. The antioxidant activity of extracts was evaluated by the 2,2-diphenyl-1-picrylhydrazine (DPPH) method. To evaluate the safety of extracts, a cytotoxicity study against HaCat, J774 and HepG2 cells was performed.Results. The extracts had no activity against the bacteria at the maximum concentration of 5.0 mg ml-1, but showed fungistatic action against Candida species and dermatophytes. The ethanolic extract showed 88 % antioxidant activity and showed no significant cytotoxicity against the previously mentioned cells.Conclusion. This study showed that the 100 % ethanolic (EtOH) extract was favourable for antifungal and antioxidant activities and did not present significant cytotoxicity against the three studied cell lines, indicating that S. purpurea leaves are promising for the development of new antimicrobials.


Assuntos
Anacardiaceae , Anti-Infecciosos , Antibacterianos , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Bactérias , Humanos , Extratos Vegetais/farmacologia
19.
Klin Lab Diagn ; 67(9): 519-524, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099461

RESUMO

Corynebacterium spp. are part of the human microbiome, but can cause the development of inflammatory diseases of various localization. Purpose - to evaluate the relationship between pathogenic properties and resistance to antimicrobial drugs (AMD) of Corynebacterium spp. from patients with inflammatory diseases of the respiratory tract. Strains of Corynebacterium spp. isolated from patients with inflammatory diseases of the respiratory tract (99 pcs.) and practically healthy individuals (33 pcs.). Isolates were identified by mass spectrometric method (MALDI-ToFMS), their adhesive and invasive activity on Hep-2 cells, cytopathic effect (CPE) in CHO-K1 cell culture, and resistance to antimicrobial drugs (AMD) were determined. Indicators of adhesion (3.65±0.679(CFU±m)x102/ml), invasion (1.72±0.230 (CFU±m)x102/ml), cytotoxicity (69.1±3.8% of dead CHO-K1 cells ) Corynebasterium spp. strains isolated from patients are higher (p≤0.05) than similar indicators in practically healthy people. 90.9% of isolates from patients had resistance to AMD, in most cases (57.6±4.9%) resistance to only one AMP was noted, less often to two (25.2±4.3%), three or more (8.08±2.7%). According to the results of correlation-regression analysis, pathogenic properties (adhesiveness, invasiveness, cytotoxicity) of Corynebacterium spp. strains isolated from patients are in close direct relationship with resistance to AMD. This indicates the importance of identifying strains of non-diphtheria corynebacteria resistant to AMDs, which, under the influence of developing resistance to AMDs, can increase their pathogenic potential, moving from commensalism to parasitism.


Assuntos
Anti-Infecciosos , Infecções por Corynebacterium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Corynebacterium , Infecções por Corynebacterium/tratamento farmacológico , Infecções por Corynebacterium/microbiologia , Farmacorresistência Bacteriana/genética , Humanos
20.
Klin Lab Diagn ; 67(9): 550-556, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099466

RESUMO

In connection with the introduction of economic sanctions against the Russian Federation by the United States, the European Union, Japan, and a number of other countries, import substitution is becoming one of the strategic objectives of the Russian economy The comparative assessment of standardness and effectiveness of six antimicrobial commercial producer-varying disks for clinical and test strains of microorganisms has been conducted. It is based on analyzing of the variation coefficient (Cv) of inhibition zone diameters, mean values, and diameter values ranges, which are indicators of reproducibility, accuracy and efficiency, respectively. Discs from BD BBL result in insignificant variations of inhibition zone diameters, providing accurate and reproducible data. Imported discs available on the national market from a friendly country produced by HiMedia Company are showed more variation and inferior in quality to BD BBL ones. There are satisfactory results for some domestic discs, but discs with imipenem, meropenem, ciprofloxacin and gentamicin are not standard enough to assure reproducible results. To have reliable data on antibiotic susceptibility of infectious agents, incoming and routine quality control of antimicrobial disks is needed as a compulsory procedure for every bacteriological laboratory.


Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Humanos , Imipenem , Meropeném , Reprodutibilidade dos Testes , Estados Unidos
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