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1.
Braz. j. biol ; 84: e249664, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345558

RESUMO

Abstract The impact of antibiotics on growth, cocoon production was assessed in addition to isolation and characterization of bacteria associated with silkworm gut of infected larvae. Larval rearing was maintained at recommended conditions of temperature and humidity. Silkworm larvae showing abnormal symptoms were collected from the control group and dissected for gut collection. Bacteria were isolated from the gut content by spreading on agar plates and incubated at 37 °C for 48 hrs. Bacterial identification and phylogenetic analysis were carried out by 16S rRNA gene sequencing. The isolated bacteria were subjected to antimicrobial susceptibility test (disc diffusion methods) by using Penicillin (10 µg/mL), Tetracycline (30 µg/mL), Amoxicillin (25 µg/mL), Ampicillin (10 µg/mL), and Erythromycin (15 µg/mL). All isolated strains showed positive results for the catalase test. We isolated and identified bacterial strains (n = 06) from the gut of healthy and diseased silkworm larvae. Based on the 16S rRNA gene sequence, isolated bacteria showed close relation with Serratia, Bacillus, and Pseudomonas spp. Notably, 83.3% of strains were resistant to Penicillin, Tetracycline, Amoxicillin, Ampicillin, and Erythromycin but 16.6% showed antibiotic susceptibility to the above-mentioned commonly used antibiotics. Silkworm larvae fed on penicillin-treated leaves showed significant improvement in larval weight, larval length, and cocoon production. Significantly higher larval weight (6.88g), larval length (5.84cm), and cocoon weight (1.33g) were recorded for larvae fed on leaves treated with penicillin as compared to other antibiotics. Isolated bacterial strains showed close relation with Serratia spp., Bacillus spp. and Pseudomonas spp.


Resumo O impacto dos antibióticos no crescimento e na produção do casulo foi avaliado, além do isolamento e caracterização das bactérias associadas ao intestino de larvas infectadas do bicho-da-seda. A criação das larvas foi mantida nas condições recomendadas de temperatura e umidade. As larvas do bicho-da-seda com sintomas anormais foram coletadas do grupo controle e dissecadas para coleta do intestino. As bactérias foram isoladas do conteúdo intestinal por espalhamento em placas de ágar e incubadas a 37° C durante 48 horas. A identificação bacteriana e a análise filogenética foram realizadas pelo sequenciamento do gene 16S rRNA. As bactérias isoladas foram submetidas a teste de sensibilidade antimicrobiana (métodos de difusão em disco) com penicilina (10 µg / mL), tetraciclina (30 µg / mL), amoxicilina (25 µg / mL), ampicilina (10 µg / mL) e eritromicina (15 µg / mL). Todas as cepas isoladas apresentaram resultados positivos para o teste da catalase. Isolamos e identificamos cepas bacterianas (n = 06) do intestino de larvas de bicho-da-seda saudáveis e doentes. Com base na sequência do gene 16S rRNA, as bactérias isoladas mostraram estreita relação com Serratia, Bacillus e Pseudomonas spp. Notavelmente, 83,3% das cepas eram resistentes a penicilina, tetraciclina, amoxicilina, ampicilina e eritromicina, mas 16,6% mostraram suscetibilidade aos antibióticos comumente usados mencionados acima. As larvas do bicho-da-seda alimentadas com folhas tratadas com penicilina apresentaram melhora significativa no peso larval, comprimento larval e produção de casulo. Peso larval significativamente maior (6,88g), comprimento larval (5,84cm) e peso do casulo (1,33g) foram registrados para larvas alimentadas com folhas tratadas com penicilina, em comparação com outros antibióticos. Cepas bacterianas isoladas mostraram estreita relação com Serratia spp., Bacillus spp. e Pseudomonas spp.


Assuntos
Animais , Bombyx , Antibacterianos/farmacologia , Filogenia , Bactérias/genética , RNA Ribossômico 16S/genética , Testes de Sensibilidade Microbiana , Larva
2.
Food Chem ; 398: 133910, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973296

RESUMO

Riboflavin (Rf), an externally supplied nutrient, is highly photosensitive, and should be protected from sunlight once used in food and pharmaceutical manufacturing. The applications of encapsulated Rf have recently developed due to their therapeutic properties. In this study, the use of green silver nanoparticles (AgNPs) synthesized by Rosa damascena mill L. extract to control the encapsulation efficiency of Rf in potato starch was demonstrated for the first time. Starch/Rf, Starch/AgNPs/Rf and Starch/AgNPs nanocapsules were characterized by Fourier-transform infrared, field emission scanning electron microscopy, differential scanning calorimetry, and brunauer-Emmett-Teller techniques. The obtained results showed that the presence of AgNPs reduces Rf nanocapsules size (from 340 to 327 nm), increases the encapsulation efficiency (21.14 ± 0.62 to 92.52 ± 1.32 %) and improves the thermal stability, antibacterial and antioxidant activities. Moreover, UV-vis spectroscopy demonstrated the stronger association of AgNPs/Rf and AgNPs/Rf/Starch nanocapsules with BSA under physiological conditions.


Assuntos
Nanopartículas Metálicas , Nanocápsulas , Solanum tuberosum , Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Riboflavina , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido , Difração de Raios X
3.
Ann Lab Med ; 43(1): 45-54, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36045056

RESUMO

Background: Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. Methods: S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. Results: Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. Conclusions: Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/farmacologia , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética , Vacinas Conjugadas/farmacologia
4.
J Ethnopharmacol ; 300: 115677, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36064148

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bioactive substance identification is always the focal point and the main challenge in Chinese herbal medicine (CHM). Most CHM present multiple efficacies and multiple tropisms, which has improved the application accuracy of CHM, and is worthy of further study. In this article, the concept of "multi-tropism efficacy of CHM" has been proposed for the first time. In addition, it is hypothesized that the different components in CHM can be classified based on their efficacy status. AIM OF THE STUDY: The spectrum-effect relationship between the fingerprint and efficacy was established to identify the efficacy status of components. This provided a practical, efficient and accurate way to identify the bioactive substances from a complex CHM system. MATERIALS AND METHODS: The network pharmacology approach was applied to preliminarily analyze the potential antibacterial compounds and mechanisms of HQ. Furthermore, its chemical fingerprint was established and the characteristic peaks were identified by LC-MS/MS. The antibacterial and anti-inflammatory bioactivities of HQ were determined to evaluate its pharmacological effect of heat-clearing and detoxification, and its anticoagulation activity was determined to evaluate its heat-clearing and tocolysis effects. The spectrum-effect relationships were assessed by gray correlation analysis to discriminate the status of active components in HQ with different efficacies. RESULTS: Network pharmacology analysis revealed apigenin, wogonin, baicalein, acacetin, ß-sitosterol, baicalin, eugenol, moslosooflavone, palmitic acid, oroxylin-A 7-O-glucuronide, and scutevulin as the potential active compounds responsible for the efficacy of HQ against both E. coli and S. aureus. The spectrum-effect relationship was utilized to reveal the orientation activities, with the results as follows: 1) The main basic-efficacy components in HQ with antibacterial, anti-inflammatory, and anticoagulant effects were P5, P8, P9, P15, P18, P19, P20; while the general basic-efficacy components were P2, P3, P6, P7, P11, P14, P21, P22, P28. 2) The main efficacy-oriented components in HQ with antibacterial effects on E. coli were P1, P12, P17, while the general efficacy-oriented compound was P10, P24, P25, P26, P27; the main efficacy-oriented in HQ with antibacterial effects on S. aureus were P14 and the general efficacy-oriented components were P1, P12, P26, P29, P30, respectively. 3) The main efficacy-oriented components with anti-inflammatory activity were P14, P24, P25, P27, and P30, while the general efficacy-oriented components were P13, P23, P26. 4) The main efficacy-oriented compounds in HQ with effects on anticoagulation were P6 and P22; these acted by prolonging APTT through the intrinsic coagulation pathway and PT through the extrinsic coagulation pathway, respectively. 5) The pharmacodynamic status classification of Scutellaria baicalensis ingredients were confirmed by nine reference compounds exemplarily. CONCLUSION: This work established a novel strategy for active compound efficacy status identification in multi-tropism Chinese herbal medicine (Scutellaria baicalensis Georgi) based on multi-indexes spectrum-effect gray correlation analysis, the method is scientific feasible and can be applied to the effective substances identification and quality control of other CHM.


Assuntos
Medicamentos de Ervas Chinesas , Scutellaria baicalensis , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anticoagulantes , Apigenina , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Escherichia coli , Eugenol , Glucuronídeos , Ácido Palmítico , Piridinolcarbamato , Scutellaria baicalensis/química , Staphylococcus aureus , Espectrometria de Massas em Tandem , Tropismo
5.
J Ethnopharmacol ; 300: 115673, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36096348

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Streptococcus mutans a key pathogen, produces biofilm, acids and extracellular polysaccharides in the oral cavity; which leads to the development of dental caries. Control of these pathogenic markers can prevent dental caries. Uvaria chamae P. Beauv. is a medicinal plant traditionally used for many ailments including oral infections. Root, leaves and bark extracts has proven antibacterial activity including activity against caries causing S. mutans. However, its effect on the virulence properties of S. mutans, responsible for the development of dental caries, has not been studied. AIM OF THE STUDY: This study investigated the phytochemical constituents, anti-S. mutans, anti-adherence and anti-acidogenic activity of U. chamae root extract. MATERIALS AND METHODS: Extracts were prepared and phytochemical analysis was performed. Minimum inhibitory concentrations (MIC) were determined, and MIC and sub-MIC concentrations of the best solvent were selected for their effect on the virulence factors of S. mutans. The results were analysed using one-way ANOVA and Wilcoxon Rank Sum Tests. RESULTS: The dichloromethane extract, with proanthocyanidin as a major chemical constituent, produced an MIC of 0.02 mg/ml. At 6 h, exposure to 0.005, 0.01, and 0.02 mg/ml extract significantly reduced S. mutans adherence by 39, 59, and 77% respectively (p < 0.05). Uvaria chamae also significantly inhibited acid production in S. mutans at 10, 12, 14 and 16 h (p < 0.05). At ½ MIC, the plant extract caused remarkable downregulation of the virulence genes responsible for the adherence, biofilm formation, extracellular polysaccharide synthesis and acid production. CONCLUSIONS: This suggests that U. chamae extract may potentially be used to inhibit the proliferation of S. mutans and silencing the expression of pathology-related genes, which will prevent the development of dental caries.


Assuntos
Cárie Dentária , Proantocianidinas , Uvaria , Ácidos , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes , Cárie Dentária/prevenção & controle , Cloreto de Metileno/farmacologia , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Solventes/farmacologia , Streptococcus mutans , Uvaria/química , Fatores de Virulência
6.
J Ethnopharmacol ; 300: 115738, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36165961

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Matayba oppositifolia (A. Rich.) Britton (commonly known as "huaya" or "palo huacax") is commonly utilized in traditional Mayan medicine for treating diarrhea and for canker and other sores. AIM OF THE STUDY: The aim of this study was to investigate the in-vitro antimicrobial activity of M. oppositifolia bark extracts against drug-susceptible and -resistant ESKAPE-E pathogens. In addition, the phytochemical composition of the best antibacterial extract was analyzed. MATERIALS AND METHODS: The bark extracts were prepared with different solvents, including water, n-hexane, ethyl acetate and methanol. These were tested against ESKAPE-E (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp., including Escherichia coli) strains using Resazurin Microtiter Assay. In addition, the composition of the most active extract was analyzed by GC-MS. RESULTS: The aqueous and organic bark extracts showed activity on drug-susceptible and -resistant ESKAPE-E microbes (MIC = 1000-31.25 µg/mL). The n-hexane bark extract was more active against the superbugs carbapenem-resistant K. pneumoniae (MIC = 500-31.25 µg/mL) and A. baumannii (MIC = 250-125 µg/mL). The GC-MS analysis of this extract allowed the identification of 12 phytochemicals as the potential antibacterial compounds. The major compounds identified were palmitic acid (1), friedelan-3-one (2) and 7-dehydrodiosgenin (3). CONCLUSION: The present study reveals the strong in-vitro antibacterial activity of the n-hexane extract from the bark of M. oppositifolia and demonstrates the potential of natural products as a source of antibacterial compounds or phytomedicines that are specifically effective against drug-resistant ESKAPE-E bugs. Additionally, our investigation contributes to the ethnopharmacological knowledge and reappraisal of Mayan medicinal flora, as well as supports the traditional use of the bark of the medicinal plant M. oppositifolia for the treatment of infectious diseases.


Assuntos
Antibacterianos , Plantas Medicinais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Carbapenêmicos/farmacologia , Escherichia coli , Hexanos , Klebsiella pneumoniae , Metanol/farmacologia , Testes de Sensibilidade Microbiana , Ácido Palmítico , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sapindaceae , Solventes/farmacologia , Água/farmacologia
7.
J Hazard Mater ; 441: 129870, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063716

RESUMO

The formation and transmission of antibiotic resistance genes (ARGs) have attracted increasing attention. It is unclear whether the internal mechanisms by which antibiotics affect horizontal gene transfer (HGT) of ARGs during anaerobic digestion (AD) were influenced by dose and type. We investigated the effects of two major antibiotics (oxytetracycline, OTC, and sulfamethoxazole, SMX) on ARGs during AD according to antibiotic concentration in livestock wastewater influent. The low-dose antibiotic (0.5 mg/L) increased ROS and SOS responses, promoting the formation of ARGs. Meanwhile, low-dose antibiotics could also promote the spread of ARGs by promoting pili, communication responses, and the type IV secretion system (T4SS). However, different types and doses of antibiotics would lead to changes in the above functional modules and then affect the enrichment of ARGs. With the increasing dose of SMX, the advantages of pili and communication responses would gradually change. In the OTC system, low-dose has the strongest promoting ability in both pili and communication responses. Similarly, an increase in the dose of SMX would change T4SS from facilitation to inhibition, while OTC completely inhibits T4SS. Microbial and network analysis also revealed that low-dose antibiotics were more favorable for the growth of host bacteria.


Assuntos
Antibacterianos , Oxitetraciclina , Anaerobiose , Animais , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Gado , Oxitetraciclina/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Sulfametoxazol , Sistemas de Secreção Tipo IV , Águas Residuárias/análise
8.
J Hazard Mater ; 441: 129897, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36084469

RESUMO

The co-existence of antibiotics and heavy metals in soil with manure application poses high risk to both environment and human health, and thus effective remediation methods are in urgent need. This study investigated the synergistic effects of electrokinetic remediation (EKR) on antibiotic resistance and arsenic (As) in co-contaminated paddy soils. EKR treatments in soil amended with pig manure (EKR-PD) showed better remediation efficiency compared with that without pig manure. In detail, the content of available As and the abundance of antibiotic-resistant bacteria (ARB) decreased by 25.2 %-41.4 % and 9.5 %-21.1 % after 7-d remediation, respectively, due to a relatively higher current density for EKR-PD. The role of the electric field contributed to 33.9 % of antibiotic degradation. Antibiotic resistance genes (ARGs) with ribosomal-protection and enzymatic-deactivation types were easier to remove, with the removal ratio of 37.8 %-41.6 % in EKR-PD. Brevundimonas was the most significantly different species during remediation. Bacillus and Clostridium_ sensu_stricto_1 were potential host bacteria of ARGs in the electric field. Membrane transport might be an effective strategy for microorganisms to respond to the stress of both electric field and co-contaminated environments. This study supports the potential role of EKR in the co-contamination of heavy metals and antibiotic resistance under manure application.


Assuntos
Arsênio , Metais Pesados , Antagonistas de Receptores de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antibacterianos/farmacologia , Bactérias/genética , Genes Bacterianos , Humanos , Esterco/microbiologia , Solo , Microbiologia do Solo , Suínos
9.
J Hazard Mater ; 441: 129954, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36116315

RESUMO

Currently, graphene quantum dots (GQDs) are widely used as antibacterial agents, and their effects are dependent on the reactive oxygen species (ROS) generated by photodynamic and peroxidase activities. Nevertheless, the supply of substrates or light greatly limits GQDs application. Besides, due to compensatory mechanisms in bacteria, comprehensive analysis of the molecular mechanism underlying the effects of GQDs based on cellular-level experiments is insufficient. Therefore, N-GQDs with inherent excellent, broad-spectrum antibacterial efficacy under acidic conditions were successfully synthesized. Then, via multi-omics analyses, the antibacterial mechanisms of the N-GQDs were found to not only involve generation ROS but also be associated with changes in osmotic pressure, interference with nucleic acid synthesis and inhibition of energy metabolism. More surprisingly, the N-GQDs could destroy intracellular acid-base homeostasis, causing bacterial cell death. In conclusion, this study provides important insights into the antibacterial mechanism of GQDs, offering a basis for the engineering design of antibacterial nanomaterials.


Assuntos
Grafite , Ácidos Nucleicos , Pontos Quânticos , Antibacterianos/farmacologia , Grafite/química , Grafite/farmacologia , Concentração de Íons de Hidrogênio , Peroxidases , Pontos Quânticos/química , Espécies Reativas de Oxigênio/metabolismo , Tecnologia
10.
Food Chem ; 400: 133960, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36063680

RESUMO

A proper understanding of silver (Ag) nanoparticles properties is fundamental for developing new antimicrobial agents. In this study, Ag nanoparticles were obtained by green synthesis methods using natural reducing agents present in extracts of apples, oranges, potatoes, red pepper, white onion, garlic and radish. The antimicrobial properties of respective nanoparticles, expressed as the minimum inhibitory concentration, were assessed against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Candida krusei. Characterization of Ag nanoparticles was done with the application of transmission electron microscopy, X-ray diffraction and UV-vis spectroscopy. The obtained results led to the conclusions that in each extract (pH from 2.1 to 6.2) were obtained specific particles (size from 9 to 30 ± 2 nm) with different antimicrobial activity. Our study indicates that plant extracts gives the Ag nanoparticles specific properties, yet the best antimicrobial properties show nanoparticles obtained in the presence of potato extract.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Escherichia coli , Química Verde/métodos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Substâncias Redutoras , Prata/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Environ Sci (China) ; 124: 472-480, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182155

RESUMO

Antibiotics have been identified as obesogens contributing to the prevalence of obesity. Moreover, their environmental toxicity shows sex dependence, which might also explain the sex-dependent obesity observed. Yet, the direct evidence for such a connection and the underlying mechanisms remain to be explored. In this study, the effects of tetracycline, which is a representative antibiotic found in both environmental and food samples, on Drosophila melanogaster were studied with consideration of both sex and circadian rhythms (represented by the eclosion rhythm). Results showed that in morning-eclosed adults, tetracycline significantly stimulated the body weight of females (AM females) at 0.1, 1.0, 10.0 and 100.0 µg/L, while tetracycline only stimulated the body weight of males (AM males) at 1.0 µg/L. In the afternoon-eclosed adults, tetracycline significantly stimulated the body weight of females (PM females) at 0.1, 1.0 and 100.0 µg/L, while it showed more significant stimulation in males (PM males) at all concentrations. Notably, the stimulation levels were the greatest in PM males among all the adults. The results showed the clear sex dependence of the obesogenic effects, which was diminished by dysrhythmia. Further biochemical assays and clustering analysis suggested that the sex- and rhythm-dependent obesogenic effects resulted from the bias toward lipogenesis against lipolysis. Moreover, they were closely related to the preference for the energy storage forms of lactate and glucose and also to the presence of excessive insulin, with the involvement of glucolipid metabolism. Such relationships indicated potential bridges between the obesogenic effects of pollutants and other diseases, e.g., cancer and diabetes.


Assuntos
Poluentes Ambientais , Compostos Heterocíclicos , Insulinas , Animais , Antibacterianos/farmacologia , Peso Corporal , Ritmo Circadiano , Drosophila melanogaster , Feminino , Glucose , Insulinas/farmacologia , Lactatos/farmacologia , Masculino , Obesidade/induzido quimicamente , Tetraciclina/toxicidade
12.
Int J Food Microbiol ; 384: 109954, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36257185

RESUMO

Gram-negative Vibrio parahaemolyticus is a halophilic human pathogen known to be the leading cause of food poisoning associated with consuming uncooked or undercooked seafood. The increasing presence and contamination of seafood have caused serious safety concerns in food facilities. Notably, it can form biofilms on food surfaces that confer resistance to antimicrobial treatments. Therefore, in the present study, the antibacterial, antibiofilm, and antivirulence activities of hydroquinone (HQ) and its 16 derivatives were investigated against V. parahaemolyticus and V. harveyi. Representative active antibacterial and antibiofilm compounds, 2,3-dimethylhydroquinone (2,3-DMHQ) and 2,5-ditert-butylhydroquinone (DBHQ), were further examined using a crystal violet assay, biochemical reactions, live cell imaging, and scanning electron microscopy. 2,3-DMHQ with a minimum inhibitory concentration (MIC) of 20 µg/mL completely inhibited biofilm formation at a sub-MIC of 15 µg/mL. And, DBHQ with an MIC of ˃1000 µg/mL reduced biofilm formation by 70 % at sub-MIC of 25 µg/mL. Both 2,3-DMHQ and DBHQ inhibited protease and indole production as well as motility phenotypes. 2,3-DMHQ decreased fimbriae production and hydrophobicity whereas DBHQ did not. Transcriptomic studies revealed that genes related to biofilm, quorum sensing (QS), and hemolysin were downregulated. In addition, 2,3-DMHQ and DBHQ prevented biofilm formation of V. parahaemolyticus on squid surfaces and 2,3-DMHQ reduced the presence of V. parahaemolyticus in a boiled shrimp model. Toxicity assays using the Caenorhabditis elegans and seed germinations models showed that they were non-to-mildly toxic. These results suggest that 2,3-DMHQ and DBHQ possess the antimicrobial properties required to control V. parahaemolyticus planktonic and biofilm states in food production facilities.


Assuntos
Vibrio parahaemolyticus , Fatores de Virulência , Humanos , Hidroquinonas/farmacologia , Biofilmes , Antibacterianos/farmacologia
13.
Int J Food Microbiol ; 384: 109963, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36274385

RESUMO

A mixed solid matrix of the depolymerized pectin (DP) and rice protein (RP) were investigated to improve the antibacterial activity of star anise essential oil (SAEO) through microencapsulation. The encapsulation was undertaken via electrostatic complexation method followed by spray drying. Under the optimized conditions, SAEO microcapsules with 92.2 % encapsulation efficiency was acquired at 3:2 of DP-to-RP, 1:3 of DP-to-SAEO and pH 4.0. DP-RP/SAEO microcapsules exhibited a spherical-shaped particle with smaller particle size, and sustained release. FTIR and morphology analysis confirmed that SAEO was successfully encapsulated in the solid matrix of microcapsules. DP-RP/SAEO microcapsules caused the destruction of cytomembranes and reduction of membrane proteins, which led to the alteration of cell membrane fluidity and integrity. Meanwhile, DP-RP/SAEO microcapsules repressed the key enzyme in tricarboxylic acid (TCA) and Hexose monophosphate pathway (HMP) cycle pathway of E. coli, S. aureus. The application experiments indicated DP-RP/SAEO microcapsules can effectively control the growth of E. coli and S. aureus in crab meatballs.


Assuntos
Braquiúros , Illicium , Óleos Voláteis , Oryza , Animais , Cápsulas , Pectinas/farmacologia , Staphylococcus aureus , Eletricidade Estática , Escherichia coli , Antibacterianos/farmacologia , Óleos Voláteis/farmacologia
14.
Methods Mol Biol ; 2555: 51-72, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36306078

RESUMO

Antimicrobial resistance (AMR) is an increasingly important global challenge for healthcare systems as well as agricultural food production systems. Our ability to prepare for, and respond to, emerging AMR threats is dependent on our knowledge of genes able to confer AMR that are circulating within various environmental, animal, and human microbiomes. Targeted, sequence-specific, detection of AMR genes and functional resistance assays, described here, carried out on metagenomic DNA gives us unique insights into the presence of AMR genes and how these are associated with mobile genetic elements that may be responsible for their dissemination and can also provide important information about the mechanisms of resistance underpinning the phenotype.


Assuntos
Antibacterianos , Anti-Infecciosos , Animais , Humanos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Metagenômica , Anti-Infecciosos/farmacologia , DNA
15.
Ann Lab Med ; 43(2): 180-186, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281512

RESUMO

Background: The incidence of early- and late-onset sepsis and meningitis in neonates due to maternal rectovaginal group B Streptococcus (GBS) colonization may differ with serotype distribution and clonal complex (CC). CC17 strains are associated with hypervirulence and poor disease outcomes. GBS serotypes are distinguished based on the polysaccharide capsule, the most important virulence factor. We determined the sequence type distribution of GBS isolates from pregnant women in Korea and validated whole-genome sequencing (WGS)-based prediction of antimicrobial susceptibility and capsular serotypes in GBS isolates. Methods: Seventy-five GBS isolates collected from pregnant Korean women visiting Wonju Severance Christian Hospital, Wonju, Korea between 2017 and 2019 were subjected to WGS using the NovaSeq 6000 system (Illumina, San Diego, CA, USA). Multilocus sequence types, serotypes, antimicrobial resistance genes, and hemolysin operon mutations were determined by WGS, and the latter three were compared with the results of conventional phenotypic methods. Results: The predominant lineage was CC1 (37.3%), followed by CC19 (32.0%), CC12 (17.3%), and CC17 (4.0%). All isolates were cps typeable (100%, (75/75), and 89.3% of cps genotypes (67/75) were concordant with serotypes obtained using latex agglutination. The cps genotypes of the 75 isolates were serotypes III (24.0%), V (22.7%), and VIII (17.3%). All isolates harboring intact ermB and tet were non-susceptible to erythromycin and tetracycline, respectively. Three non-hemolytic strains had 1-bp frameshift insertions in cylE. Conclusions: The low prevalence of CC17 GBS colonization may explain the low frequency of neonatal GBS infections. WGS is a useful tool for simultaneous genotyping and antimicrobial resistance determination.


Assuntos
Gestantes , Infecções Estreptocócicas , Recém-Nascido , Feminino , Humanos , Gravidez , Proteínas Hemolisinas/genética , Tipagem de Sequências Multilocus , Streptococcus agalactiae , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Eritromicina , Tetraciclina , Fatores de Virulência/genética
16.
Ann Lab Med ; 43(2): 196-199, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281514

RESUMO

Imipenemase (IMP)-6-producing Pseudomonas aeruginosa sequence type (ST) 235 is a dominant clone of carbapenemase-producing P. aeruginosa (CPPAE) in Korea. As part of the Antimicrobial Resistance Surveillance System in Korea, we found an increase in the carbapenem resistance rate of P. aeruginosa isolates from blood cultures and a shift in the molecular epidemiology of CPPAE. A total of 212 non-duplicated P. aeruginosa blood isolates were obtained from nine general hospitals and two nursing homes. Twenty-four isolates were identified as CPPAE. We observed the emergence of the NDM-1 P. aeruginosa ST 773 clone (N=10), mostly from Gyeongsang Province. The IMP-6 ST 235 clone (N=11) was detected in all provinces. CPPAE isolates showed very high resistance rates to amikacin, and all NDM-1 P. aeruginosa strains carried rmtB. This is the first nationwide surveillance of the recently emerged NDM-1-producing P. aeruginosa ST773 clone in Korea. Continuous surveillance is necessary to prevent the infection and transmission of carbapenem- and amikacin-resistant P. aeruginosa in Korea.


Assuntos
Anti-Infecciosos , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa/genética , RNA Ribossômico 16S/genética , Epidemiologia Molecular , Amicacina/farmacologia , Inosina Monofosfato , beta-Lactamases/genética , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Células Clonais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/epidemiologia
17.
J Colloid Interface Sci ; 630(Pt B): 511-522, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334487

RESUMO

Diseases caused by bacterial infection are becoming a major threat to human health. Therefore, developing efficient antibacterial materials is of great significance in improving medical care and protecting people's health. In this work, an accordion-like structural Ti3C2@CuS was synthesized by copper sulfide (CuS) nanospheres anchored firmly on the surface of Ti3C2Tx via the hydrothermal method. The multilayer Ti3C2@CuS becomes few-layered nanosheets after ultrasonic treatment, which have an enjoyable dispersion in the polyurethane (PU) matrix. PU and the released Cu2+ from Ti3C2@CuS are firmly linked by a coordination bond, which improves the mechanical properties and thermal stability of Ti3C2@CuS-PU and reduces the heavy metal ion pollution by blocking the Cu2+ released by forming coordination bonds. Moreover, Ti3C2@CuS-PU exhibits an excellent self-healing performance after 30 tensile cycles. Additionally, Ti3C2Tx and CuS could improve the separation efficiency of the electron-hole pairs of CuS to produce more reactive oxygen species (ROS) to kill bacteria. Ti3C2@CuS-PU maintains a highly long-term sterilization ability of more than 90 % in 30 days because of the synergistic effect of the sustained release of copper ions, the elevated ROS production ability, and the excellent dispersion of Ti3C2@CuS in PU. This work demonstrates a simple and promising route for designing multifunctional antibacterial self-healing materials.


Assuntos
Cobre , Poliuretanos , Humanos , Cobre/farmacologia , Cobre/química , Poliuretanos/farmacologia , Espécies Reativas de Oxigênio , Antibacterianos/farmacologia , Antibacterianos/química , Sulfetos
18.
Bioresour Technol ; 367: 128253, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334868

RESUMO

Improper disposal of antibiotic fermentation dregs poses a risk of releasing antibiotics and antibiotic resistant bacteria to the environment. Therefore, this study evaluated the effects of biochar addition to lincomycin fermentation dregs (LFDs) composting. Biochar increased compost temperature and enhanced organic matter decomposition and residual antibiotics removal. Moreover, a 1.5- to 17.0-fold reduction in antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) was observed. Adding biochar also reduced the abundances of persistent ARGs hosts (e.g., Streptomyces, Pseudomonas) and ARG-related metabolic pathways and genes (e.g., ATP-binding cassette type-2 transport, signal transduction and multidrug efflux pump genes). By contrast, compost decomposition improved due to enhanced metabolism of carbohydrates and amino acids. Overall, adding biochar into LFDs compost reduced the proliferation of ARGs and enhanced microbial community metabolism. These results demonstrate that adding biochar to LFDs compost is a simple and efficient way to decrease risks associated with LFDs composting.


Assuntos
Compostagem , Lincomicina , Antibacterianos/farmacologia , Fermentação , Esterco/microbiologia , Genes Bacterianos/genética , Resistência Microbiana a Medicamentos/genética
19.
J Colloid Interface Sci ; 630(Pt B): 611-622, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36335779

RESUMO

Increasing the surface contact area (SCA) between active materials of triboelectric nanogenerator (TENG) can effectively enhance energy harvesting performance. In the meantime, owing to potential intimate contacts between skin and wearables, hygienic aspects of TENG devices with high SCA become important. Herein, we present a robust route to fabricate flexible TENGs with antimicrobial capability realized by nano-patterning thermoplastic polyurethane (TPU) thin films. Without involving sophisticated equipment and time-consuming technique, simply tuning curing conditions of capillary force lithography could precisely control the nanostructure geometry. Our topographically designed TENGs could promote higher power generation while preventing biofilm formation without adding any chemical additives. Analysis of pattern amplitude and wavelength correlation to output power is uniquely provided for a deeper understanding of how patterns enable peak performance of TENGs. Furthermore, a prototype TENG was innovatively applied to a smart device as a transparent screen sensor. Specific finger trajectories could be recognized by different electric responses, and as-generated electricity can be directly charged into comercial capacitors. Our proposed TENGs with critical hygienic advancements are expected to open avenues for TENG-incorporated wearables in the post-pandemic era.


Assuntos
Nanoestruturas , Eletricidade , Antibacterianos/farmacologia
20.
J Colloid Interface Sci ; 630(Pt B): 911-923, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36368131

RESUMO

HYPOTHESIS: Designed antimicrobial lipopeptides (ALPs) offer the attractive benefits of short peptide sequences and flexible tuning of amphiphilicity by altering the acyl chain length. These lipopeptides kill microbes by forming intriguing in-membrane nanostructures and causing the leakage of internal contents. However, how subtle differences in the molecular structures of the lipopeptides affect their antimicrobial efficacy and biocompatibility to host cells is still under-investigated. EXPERIMENTS: This work focuses on assessing changes in the acyl chain length of CH3(CH2)n-2CO-KKKIII-NH2 (n = 10, 12 and 14, K = lysine, I = isoleucine, denoted as CnKI3) on the antimicrobial potency and cytotoxicity by combining biological assays with physical measurements. Aggregation properties were characterized by changes in critical aggregation concentration (CAC) from surface tension measurements. Antimicrobial susceptibility tests, cytotoxic MTT assays, haemolytic tests, and dynamic bactericidal experiments were employed to reveal their bioactive potency toward different types of cells. To further investigate lipopeptides' underlying antimicrobial and cytotoxic mechanisms, lipid monolayer and lipid small unilamellar vesicle (SUV) models were established and biophysically characterized. FINDINGS: An increase in n led to the decrease in the CAC of CnKI3, showing a rising membrane-lytic power. Subsequent bioactive measurements revealed the optimal performance of C12KI3 from this series of lipopeptides. The selective membrane binding behaviour was well supported by neutron reflection data from charged lipid monolayer models, revealing membrane-supported nanostructures of ALPs. However, increased membrane-lytic actions in C14KI3 led to notably increased toxicity and reduced selectivity. On the other hand, C14KI3 can impose faster dynamic killing than natural lipopeptide polymyxin B, showing the distinct impact of the amphiphilic balance from the designed lipopeptide. In contrast, the distinctly weaker binding to zwitterionic membrane models (monolayers and SUVs) provided direct nanoscale structural evidence to the mildness of the designed ALPs on host cells. This work demonstrates the high selectivity and fast killing of rationally designed short ALPs to microbes via in-membrane nanostructuring.


Assuntos
Anti-Infecciosos , Lipopeptídeos , Lipopeptídeos/farmacologia , Lipopeptídeos/química , Antibacterianos/farmacologia , Antibacterianos/química , Tensão Superficial , Sequência de Aminoácidos
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