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1.
Braz. j. biol ; 84: e256944, 2024. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364507

RESUMO

In order to ensure the timely and uninterrupted supply of medicinal plant raw materials, the methods of cultivation of plant cell cultures, namely, the production of plant root cultures, are relevant. In this paper, the geroprotective potential of Hedysarum neglectum Ledeb and Panax ginseng C. A. Mey root cultures is studied. They were cultured under in vitro conditions by transforming the rhizome (H. neglectum) and seed seedlings (P. ginseng) with Agrobacterium rhizogenes 15834 Swiss. To identify the geroprotective potential, the antimicrobial disc-diffusion method and the antioxidant activity were analyzed by titration of KMnO4 extracts of plant root cultures. The qualitative and quantitative composition was analyzed using high-performance liquid chromatography, thin-layer chromatography, and gas chromatography with mass spectrometry. In the course of the work, the presence of antimicrobial and antioxidant activity of plant root culture extracts was established. Biologically active substances contained in extracts of Hedysarum neglectum Ledeb root crops and Panax ginseng C. A. Mey are characterized by geroprotective potential, so they can act as a source of natural antioxidants in the functional nutrition of the geroprotective orientation.


Para garantir o abastecimento em tempo e ininterrupto de matérias-primas de plantas medicinais, são relevantes os métodos de cultivo de culturas de células vegetais, nomeadamente a produção de culturas de raízes vegetais. Neste trabalho, foi estudado o potencial geroprotetor de culturas de raízes de Hedysarum neglectum Ledeb e Panax ginseng C. A. Mey. Eles foram cultivados em condições in vitro pela transformação do rizoma (H. neglectum) e mudas de sementes (P. ginseng) com Agrobacterium rhizogenes 15834 Swiss. Para identificar o potencial geroprotetor, o método antimicrobiano de difusão em disco e a atividade antioxidante foram analisados por titulação de extratos de KMnO4 de raízes de plantas. A composição qualitativa e quantitativa foi analisada por cromatografia líquida de alta eficiência, cromatografia em camada delgada e cromatografia gasosa com espectrometria de massa. No decorrer do trabalho, foi constatada a presença de atividade antimicrobiana e antioxidante dos extratos de raízes de plantas. Substâncias biologicamente ativas contidas em extratos de raízes de H. neglectum Ledeb e P. ginseng C. A. Mey são caracterizadas pelo potencial geroprotetor, podendo atuar como fonte de antioxidantes naturais na nutrição funcional da orientação geroprotetora.


Assuntos
Plantas Medicinais , Raízes de Plantas , Panax , Anti-Infecciosos , Antioxidantes
2.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360228

RESUMO

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.


Assuntos
Ortodontia , Desmineralização , Esmalte Dentário , Nanopartículas , Anti-Infecciosos
3.
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
4.
Carbohydr Polym ; 301(Pt B): 120328, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36446505

RESUMO

An antimicrobial thermoplastic starch (TPS) was developed by melt-mixing TPS with chlorhexidine gluconate (CHG) and epoxy resin (Er). The tensile strength and hardness of the TPSCh blend increased with the addition of Er (TPSCh/Er), especially at 5 wt% Er (TPSCh/Er5) (19.5 MPa and 95 %, respectively). The water contact angle of TPSCh/Er was higher than those of TPS and TPSCh because of the improved interfacial tension. Fourier transform infrared and nuclear magnetic resonance analyses confirmed the reaction between the epoxy groups of Er, hydroxyl groups of starch, and amino groups of CHG. TPSCh/Er5 exhibited a significantly lower CHG release than TPSCh owing to the rearrangement of TPSCh chains via Er crosslinking. TPSCh/Er0.5 and TPSCh/Er1 showed inhibition zones against both tested bacteria (Staphylococcus aureus and Bacillus cereus), whereas TPSCh/Er2.5, TPSCh/Er5, and TPSCh/Er10 showed inhibition zones only against S. aureus. Moreover, TPSCh and TPSCh/Er0.5-2.5 exhibited inhibition zones with Saccharomyces cerevisiae.


Assuntos
Anti-Infecciosos , Resinas Epóxi , Amido , Staphylococcus aureus , Antibacterianos
5.
Methods Mol Biol ; 2601: 153-167, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36445583

RESUMO

The development of safe antimicrobial agents is important for the effective treatment of pathogens. From a multitude of discovered inhibitory compounds, only a few antimicrobial agents are able to enter the market. Many antimicrobials are, on the one hand, quite effective in killing pathogens but, on the other hand, cytotoxic to eukaryotic cells. Cell health can be monitored by various methods. Plasma membrane integrity, DNA synthesis, enzyme activity, and reducing conditions within the cell are known indicators of cell viability and cell death. For a comprehensive overview, methods to analyze cytotoxic and hemolytic effects, e.g., lactate dehydrogenase release, cell proliferation analysis, cell viability analysis based on the activity of different intracellular enzymes, and hemolysis assay of antimicrobial compounds on human cells, are described in this updated chapter.


Assuntos
Anti-Infecciosos , Humanos , Anti-Infecciosos/farmacologia , Testes Imunológicos , Antibacterianos/farmacologia , Sobrevivência Celular , Hemólise
6.
Methods Mol Biol ; 2601: 55-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36445579

RESUMO

Natural product discovery campaigns aim to identify compounds with the desired bioactivity, for example, metabolites with antibiotic activity. The major driver of many projects is still the finding of bioactive extracts, which will be followed up to isolate the activity-causing agent as pure compound. However, nowadays also additional strategies can be used to increase the probability of success. Metabolomic approaches indicate chemical novelty, and genomics allow identification of putative biosynthetic gene clusters (BGCs) of interest, even though the corresponding metabolite is unknown. Whatever the entry to the campaign is, at one point the scientists need to have the desired compound in hand to analyze it in detail. Hence, expression must be achieved to yield the compound of interest, either to link it to the corresponding putative BGC or to overcome the bottleneck of sparse compound supply. Therefore, homologous and heterologous expression approaches are feasible ways forward to increase production yield, shorten fermentation time, or to get BGCs expressed at all for which no suitable fermentation condition was identified.In this chapter, expression approaches in bacteria are described to biosynthesize compounds of interest. Homologous expression, by genetic manipulation of the original Streptomyces producer strain, and heterologous expression in the microbial workhorse Escherichia coli are exemplified.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Streptomyces , Humanos , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Streptomyces/genética , Escherichia coli/genética
7.
Methods Mol Biol ; 2601: 271-281, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36445589

RESUMO

The bacterial cytoplasmic membrane separates the cell from its environment and acts as a selective permeability barrier. In addition, it functions in energy conservation, transport, signaling, and biosynthesis processes. Antimicrobial agents disrupting these functions may lead to pleiotropic effects, including leakage of low molecular weight compounds such as ions, amino acids, and ATP and subsequent membrane depolarization. This updated chapter describes two techniques to assess antibiotic-induced membrane impairment in vivo.


Assuntos
Anti-Infecciosos , Anti-Infecciosos/farmacologia , Membranas , Antibacterianos/farmacologia , Membrana Celular , Aminoácidos
8.
Sci Total Environ ; 858(Pt 1): 159807, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461568

RESUMO

Antibiotics have been widely used for improving human and animal health and well-being for many decades. However, the enormous antibiotic usage in agriculture especially for livestock leads to considerable quantities of antibiotic residues in associated food products and can reach potentially hazardous levels for consumers. Therefore, timely detection and systematical surveillance on residual antibiotics in food materials are of significance to minimize the negative impact caused by such unwanted antibiotic leftovers. To this end, we constructed a cloud-platform-based system (ARSCP) for comprehensive surveillance of antibiotic residues in food materials. With the system, we collected 126,560 samples from 68 chicken farms across China and detected the antibiotic residues using a rapid detection colorimetric commercial (Explorer 2.0) kit and UPLC-MS/MS. Only 108 (0.085 %) of the samples contained residual antibiotics exceeding the MRLs and all data were subjected to ARSCP system to provide a landscape of antibiotic residues in China. As a proof-of-concept, we provided an overview of residual antibiotics based on data from China, but the system is generally applicable to track and monitor the antibiotic residues globally when the data from other countries are incorporated. We used the combined Explorer 2.0 and MS data to construct ARSCP, an antimicrobial residue surveillance cloud platform for raw chicken samples. ARSCP can be used for rapid detection and real-time monitoring of antibiotic residues in animal food and provides both data management and risk warning functions. This system provides a solution to improve the management of facilities that must monitor antibiotic MRLs in food animal products that can reduce the pollution of antibiotics to the environment.


Assuntos
Anti-Infecciosos , Computação em Nuvem , Animais , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Antibacterianos , Ração Animal , Progressão da Doença
9.
Food Microbiol ; 110: 104159, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36462815

RESUMO

Salmonella enterica is a ubiquitous and multi-host pathogen that causes significant morbidity and mortality worldwide. Outbreaks of foodborne salmonellosis continue to occur, highlighting the need for additional interventions. The present study investigated the potential for the commercial protective culture Hafnia alvei B16 to provide enhanced protection against multi-drug resistant strains of S. enterica serovars Typhimurium and Newport by attenuating their virulence when cocultured in milk (as a model food) and broth, and by protecting intestinal epithelial cells from pathogen infection in vitro. Exposure to HA in milk inhibited the subsequent adhesion of S. Typhimurium by 95.23%, whereas the invasion capacity of both serovars was reduced when cocultured with HA in broth and milk. The inhibition of invasion by S. Typhimurium and S. Newport was greater when cocultured in milk (86.95% and 86.58%, respectively) compared to broth (51.64% and 79.88%, respectively). Exposure to HA in both media decreased the expression of virulence genes in S. Typhimurium and S. Newport. Pre-treatment of Caco-2 cells with HA reduced invasion of S. Newport by 89.68% compared to control. These data demonstrate the potential for HA to enhance food safety by attenuating Salmonella virulence and protecting against pathogen invasion of intestinal epithelial cells.


Assuntos
Anti-Infecciosos , Hafnia alvei , Humanos , Animais , Células CACO-2 , Salmonella , Intestinos , Leite
10.
J Mol Graph Model ; 118: 108368, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36335830

RESUMO

Cathelicidin antimicrobial peptides are a diverse family of cationic amphipathic peptides with multiple activities. In humans, cathelicidin LL-37 is one of the main host defense peptides with a remarkable medical and biotechnological potential. Deregulation of LL-37 expression has been associated with inflammatory diseases. However the effects of point mutations driven by single nucleotide polymorphisms (SNPs) on LL-37 are unknown. Here we applied an array of computational tools to investigate the effects of such mutations on LL-37 structure and activity. Due to the fact that, on cathelicidins, the prodomain is more conserved than the mature peptide, the SNP effect predictions were biased and, overall, resulted in neutral effects; and due to the slight changes in physicochemical properties, the antimicrobial predictions indicated the maintenance of such activity. Nonetheless, R07P, R07W, R29Q, R29W mutations reduced the peptide net charge, which in turn could result in less active LL-37 variants. Molecular dynamics data indicated that R07Q and N30Y mutations altered the LL-37 structure, leading to potential deleterious effects. In addition, the helix dipole is altered in G03A, R07P, R07W and L31P mutations, which could also alter the antimicrobial activity. Our results indicated that despite the mutations did not alter the residues from LL-37 active core, they could influence the antimicrobial activity and consequently, could be involved in inflammatory diseases.


Assuntos
Anti-Infecciosos , Mutação Puntual , Humanos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/química , Catelicidinas/genética , Catelicidinas/química , Catelicidinas/metabolismo , Anti-Infecciosos/química
11.
J Ethnopharmacol ; 302(Pt A): 115830, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36243295

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Thymus mastichina (L.) L. (TM) and Cistus ladanifer L. (CL) are two Portuguese autochthonous species with traditional skin application in folk medicine. TM is majorly known for its antiseptic and wound healing properties, as an external anti-inflammatory agent and for its application in folk cosmetics and hygiene products. Its use in acne vulgaris has also been reported. CL is traditionally used in remedies for wounds, ulcers and other skin ailments such as psoriasis and eczema. Its application has been found useful due to its anti-inflammatory, astringent, wound healing and antiseptic properties. AIM OF THE STUDY: With this work, we aimed to investigate relevant bioactivities related with the traditional application of TM and CL essential oils (EOs) and hydrolates (by-products of EO production) in skin ailments. Specifically their in vitro antioxidant, anti-inflammatory, cytotoxic, wound healing and antimicrobial properties were evaluated. The chemical composition of both EOs and respective hydrolates was also characterized. MATERIALS AND METHODS: Chemical characterization of EOs and hydrolates was performed by GC-FID and GC-MS. Cellular biocompatibility was evaluated using the MTT assay in macrophages (RAW 264.7) and fibroblasts (L929) cell lines. Anti-inflammatory activity was investigated by studying nitric oxide (NO) production by macrophages with Griess reagent. Wound healing potential was evaluated with the scratch-wound assay. The antioxidant potential was studied by the DPPH scavenging method. Antimicrobial activity was evaluated by broth microdilution assay against relevant microbial strains and skin pathogens, namely Staphylococcus aureus, Staphylococcus epidermidis, Cutibacterium acnes, Pseudomonas aeruginosa, Escherichia coli, Candida albicans and Aspergillus brasiliensis. RESULTS: The major compounds present in TM and CL EOs were 1,8-cineole and α-pinene, respectively. 1,8-cineole and E-pinocarveol were the major compounds in the correspondent hydrolates. CL EO presented the highest anti-inflammatory potential [EC50 = 0.002% (v/v)], still with significant cytotoxicity [IC50 = 0.012% (v/v)]. TM preparations presented anti-inflammatory potential, also presenting higher biocompatibility. The same profile was present on fibroblasts regarding biocompatibility of the tested preparations. CL EO and hydrolate increased fibroblasts' migration by 155.7% and 148.4%, respectively. TM hydrolate presented a milder activity than CL hydrolate, but wound healing potential was still present, increasing cell migration by 125.1%. All preparations presented poor antioxidant capacity. CL EO presented higher antimicrobial activity, with MICs ranging from 0.06% (v/v) to 2% (v/v), against different microorganisms. CONCLUSIONS: Anti-inflammatory and skin repairing potential were present for CL preparations. TM hydrolate presented an interesting biocompatible profile on both cell lines, also presenting anti-inflammatory potential. Furthermore, EOs from both species presented antimicrobial activity against a panel of different microorganisms. These in vitro bioactivities support some of their traditional skin applications, specifically regarding their antiseptic, wound healing and anti-inflammatory uses.


Assuntos
Anti-Infecciosos Locais , Anti-Infecciosos , Cistus , Óleos Voláteis , Thymus (Planta) , Antioxidantes/farmacologia , Antioxidantes/química , Eucaliptol , Thymus (Planta)/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Escherichia coli , Anti-Inflamatórios/farmacologia
12.
Environ Res ; 216(Pt 2): 114594, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257451

RESUMO

The ability of cobalt nanoparticles (CoNPs) to absorb electromagnetic waves led to their use as potential biomedical agents in recent years. The properties of magnetic fluid containing cobalt nanoparticles are extraordinary. Hence, this research was designed to evaluate the Co(NO3)2 reducing the potential of orange peel aqueous extract and assessed their antimicrobial and antioxidant activities. The aqueous extract derived from orange peel had the potential to fabricate the CoNPs from 1 M Co(NO3)2 and the synthesized CoNPs were successfully characterized by standard nanoparticles characterization techniques such as UV-vis spectrophotometer, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), and Dynamic light scattering (DLS) analyses. The FTIR analysis revealed that the synthesized CoNPs were capped with active functional groups. It was characterized by predominant peaks corresponding to carbonyl (CO), amide (CO = ), and C-O of alcohols or phenols. The size and shape of CoNPs were found as 14.2-22.7 nm and octahedral, respectively, under SEM analysis. Furthermore, at increased concentration, the CoNPs demonstrated remarkable antimicrobial activity against common bacterial (Escherichia coli, Staphylococcus aureus,Bacillus subtilis, and Klebsiella pneumoniae) and fungal (Aspergillus niger) pathogens. Furthermore, these CoNPs also showed considerable in-vitro antioxidant activities against various free articles such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Hydrogen Peroxide (H2O2). These results suggest that OP aqueous extract synthesized CoNPs possess considerable biomedical applications.


Assuntos
Anti-Infecciosos , Citrus sinensis , Nanopartículas Metálicas , Antioxidantes/farmacologia , Prata/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Cobalto , Peróxido de Hidrogênio , Extratos Vegetais/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli
13.
Biochim Biophys Acta Gen Subj ; 1867(1): 130253, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228877

RESUMO

BACKGROUND: Cells exposed to stress factors experience time-dependent variations of metabolite concentration, acting as reliable sensors of the effective concentration of drugs in solution. NMR can detect and quantify changes in metabolite concentration, thus providing an indirect estimate of drug concentration. The quantification of bactericidal molecules released from antimicrobial-treated biomedical materials is crucial to determine their biocompatibility and the potential onset of drug resistance. METHODS: Real-time NMR measurements of extracellular metabolites produced by bacteria grown in the presence of known concentrations of an antibacterial molecule (irgasan) are employed to quantify the bactericidal molecule released from antimicrobial-treated biomedical devices. Viability tests assess their activity against E. coli and S. aureus planktonic and sessile cells. AFM and contact angle measurements assisted in the determination of the mechanism of antibacterial action. RESULTS: NMR-derived concentration kinetics of metabolites produced by bacteria grown in contact with functionalized materials allows for indirectly evaluating the effective concentration of toxic substances released from the device, lowering the detection limit to the nanomolar range. NMR, AFM and contact angle measurements support a surface-killing mechanism of action against bacteria. CONCLUSIONS: The NMR based approach provides a reliable tool to estimate bactericidal molecule release from antimicrobial materials. GENERAL SIGNIFICANCE: The novelty of the proposed NMR-based strategy is that it i) exploits bacteria as sensors of the presence of bactericidal molecules in solution; ii) is independent of the chemo-physical properties of the analyte; iii) establishes the detection limit to nanomolar concentrations.


Assuntos
Anti-Infecciosos , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Anti-Infecciosos/farmacologia
14.
Sci Total Environ ; 858(Pt 1): 159820, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349623

RESUMO

Parabens, triclosan (TCS), and triclocarban (TCC) are antimicrobial additives that are widely used in personal care products (PCPs) and may dysregulate infant gut microbiota and induce a series of chronic diseases. Dietary intake may be an underestimated exposure route of such antimicrobial additives in infants, but relevant data remain scarce. Therefore, this study determined five common preservatives, including methyl- (MeP), ethyl- (EtP), propyl- (PrP), butyl- (BuP), and benzyl-paraben (BeP), and two antimicrobials TCS and TCC, in major infant food sources (breastmilk, milk-based infant formula [MIF], and cereal-based complementary food [CCF]) in southern China. The health risks associated with dietary exposure among infants across different months of age were also evaluated. The results demonstrated a high incidence of MeP, EtP, PrP, and BeP in processed infant food products, while TCS and TCC were mainly detected in maternal breastmilk. Notably, MeP and EtP were found in all of the MIFs tested, while MeP, EtP, and BeP were detected in 85.6 %-100 % of the CCFs. By incorporating the human equivalent dose and an additional 10-fold margin of safety for infants into the health risk assessment, the 95th percentile hazard quotient of PrP via the ingestion of breastmilk among neonates exceeded 1. For the first time, the results showed that exposure to PrP via breastmilk intake may pose a considerable health risk to urban neonates in southern China. The health risks caused by antimicrobial exposure via ingesting MIF and CCF among infants were negligible. Thus, we recommend breastfeeding women reduce their consumption of PCPs and processed food, especially during the first month after delivery.


Assuntos
Anti-Infecciosos , Triclosan , Lactente , Recém-Nascido , Humanos , Feminino , Parabenos/análise , Triclosan/análise , Aleitamento Materno , Anti-Infecciosos/efeitos adversos , Antibacterianos , China , Exposição Ambiental/análise
15.
Food Chem ; 404(Pt B): 134760, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444088

RESUMO

Nisin (NIS) Z was incorporated (0.05 %, 0.1 %, 0.2 %) into edible films based on chitosan lactate (CHL) and 75/25 blends of polysaccharides (corn starch (CS), wheat starch (WS), oxidized potato starch (OPS), pullulan (PUL)) with CHL. The increase in the NIS/polymer ratio promoted the diffusion-driven release. Compared with the fully dissolvable CHL and PUL/CHL carriers, the starch/CHL films had limited solubility (≈27-37 %) and, consequently, ensured slower/incomplete release of NIS. The assayable NIS half-release times, determined in water, ranged from <1 min to ∼13 h. Probably due to the similar pH (≈4.5), there were generally no large differences between the antibacterial activities of the formulations. The NIS-supplemented systems limited the growth of some pathogens (B. cereus, L. monocytogenes, S. aureus), phytopathogens (P. carotovorum), and bacterial starter cultures. The NIS improved the UV-blocking ability of the films, but the 0.2 % NIS addition weakened (by ≈17-32 %) the tensile strength of most of the films.


Assuntos
Anti-Infecciosos , Quitosana , Nisina , Nisina/farmacologia , Quitosana/farmacologia , Ácido Láctico , Staphylococcus aureus , Preparações de Ação Retardada , Antibacterianos/farmacologia , Amido
16.
J Enzyme Inhib Med Chem ; 38(1): 319-329, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36440644

RESUMO

We evaluated the effects of dentine biomodification after pre-treatment with two sulphonamide carbonic anhydrase inhibitors (CAIs) of the N-[4-sulphamoylphenethylcarbamoyl]benzenesulphonamide type, investigating matrix metalloproteases activity, resin-dentine micro tensile bond strength, dentine surface wettability, and antimicrobial activities. Ninety-five sound-extracted human molars were selected for the study. Inhibitory effects were evaluated by gelatinase and collagenase activity tests and collagen degradation FT-IR spectroscopic analysis. Pre-treatment with the two CAIs kept the micro tensile values after 12 months of storage (32.23 ± 5.95) and cariogenic challenge (34.13 ± 2.71) similar to the initial, pre-treatment values (33.56 ± 4.34). A decreased Streptococcus mutans biofilm formation on dentine surfaces and antibacterial activity against planktonic bacteria were observed after CAI treatment. Dentine pre-treatment with sulphonamide CAIs maintained adhesion strength stability, allowed better dentine wettability, maintained matrix collagen, and showed anti-S. mutans activity.


Assuntos
Anti-Infecciosos , Dentina , Humanos , Dentina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfonamidas/farmacologia , Colágeno , Anti-Infecciosos/farmacologia
17.
Meat Sci ; 196: 109030, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36368289

RESUMO

Escherichia coli (E. coli) O157:H7- contaminated pork and production environments, are often a major source of foodborne outbreaks. This study evaluated the inhibition of E. coli O157:H7 on artificially contaminated raw pork loins using lytic bacteriophage (phage) and lactic acid (LA). Pork samples were inoculated with 106 CFU/mL of E. coli O157:H7 cocktail and stored at 4 °C for 30 min for the initial surface attachment. Inoculated pork loins were randomly assigned to a treatment group (Control, DI water, LA 2.5%, phage 5%, and LA 2.5% + phage 5%; n = 6/group/replication). Following antimicrobial treatments and marination for 1 h, surface microbial population was enumerated. Phage 5% significantly reduced (P < 0.05) the microbial load by 1.90 logs in pre-tenderized loins and > 2.50 logs in post-tenderized loins. Likewise, the combined treatment of phage 5% and LA 2.5% significantly reduced (P < 0.05) the microbial load by 1.89 logs in pre-tenderized loins and > 1.75 logs in post-tenderized loins. The data showed that the use of lytic bacteriophages and lactic acid as antimicrobials can result in a reduced risk of E. coli O157:H7 on the surface of pork loins.


Assuntos
Anti-Infecciosos , Bacteriófagos , Escherichia coli O157 , Carne de Porco , Carne Vermelha , Suínos , Animais , Bacteriófagos/fisiologia , Microbiologia de Alimentos , Ácido Láctico/farmacologia , Manipulação de Alimentos , Contagem de Colônia Microbiana , Anti-Infecciosos/farmacologia
18.
Food Chem ; 403: 134292, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36166926

RESUMO

Antimicrobial food grade hydroxybenzaldehyde derivatives were immobilized on the surface of chitosan films by means of reversible Schiff bases. Spectroscopy and elemental analysis evidenced the different ability of the aldehydes to form Schiff bases with chitosan. Chitosan films modified with Schiff bases of aldehydes exerted antimicrobial properties against E. coli under mild acidic environments. The efficacy of the films lied on the reversibility of synthetized imine bonds and release of the aldehydes which was promoted in mildly acid aqueous solutions. Besides acidity, imine bond reversibility depended on the chemical structure of the aldehyde covalently bonded. Films carrying salicylaldehyde presented the highest in vitro antimicrobial performance and thus, they were chosen to evaluate their effectivity in inhibiting E. coli proliferation in freshly-squeezed carrot-orange juice. Films were successfully activated by the acid environment of the juice and reduced the population of the inoculated pathogen. Salicylaldehyde migrated to the juice did not exert toxic effects on Caco-2 cells.


Assuntos
Anti-Infecciosos , Quitosana , Humanos , Bases de Schiff/farmacologia , Bases de Schiff/química , Quitosana/farmacologia , Quitosana/química , Escherichia coli , Células CACO-2 , Aldeídos/farmacologia , Aldeídos/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Concentração de Íons de Hidrogênio
19.
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
20.
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
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