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1.
Braz. j. biol ; 84: e254016, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364529

RESUMO

The present study was conducted to isolate and characterize bacteria from water and soil sample taken from the Lahore Canal at different sites i.e. Mall Road, Mohlanwal and Khera site. Isolated bacterial strains were identified on the basis of morphological and biochemical tests. Identification was confirmed by culturing bacteria on selective media. Antibiotic resistance test was also performed to observe the resistance of bacteria against different antibiotics. Blood agar test was performed for identification of different pathogenic bacteria. The result revealed that water and soil samples of Lahore Canal Lahore from different sites were contaminated with Escherichia coli, Salmonella sp., Vibrio sp., Bacillus spp., Enterococcus sp. and Staphylococcus spp. Due to presence of these pathogens, this water is not suitable for any domestic and irrigation use. Study also revealed that water of the Lahore Canal is harmful for human health as it is contaminated with bacteria that can cause severe disease e.g., Escherichia coli can cause gastroenteritis, Bacillus spp. can cause nausea and vomiting, Enterococcus may infect urinary tract, Salmonella sp. is responsible for Bacteremia, Staphylococcus spp. can cause mild fever and Vibrio sp. can be the reason of cholera. Thus it is rendered unfit for any kind of human use even other than drinking like swimming, bathing, washing etc., until and unless some remedial measures are employed to eradicate pathogenic microorganisms by WASA and LWMS according to standards of WHO. Similarly, it is quite harmful, when and where ever it is used for irrigation without proper treatment.


O presente estudo foi realizado para isolar e caracterizar bactérias de amostras de água e solo retiradas do Canal Lahore, em Lahore, em diferentes locais, ou seja, Mall Road, Mohlanwal e Khera. As cepas bacterianas isoladas foram identificadas com base em testes morfológicos e bioquímicos. A identificação foi confirmada por cultura de bactérias em testes de meios seletivos. O teste de resistência aos antibióticos também foi realizado para observar a resistência das bactérias a diferentes antibióticos. Foi realizado o teste de ágar sangue para identificar diferentes bactérias patogênicas. O resultado revelou que amostras de água e solo do Canal Lahore, Lahore, de diferentes localidades estavam contaminadas com Escherichia coli, Salmonella sp., Vibrio sp., Bacillus spp., Enterococcus sp. e Staphylococcus spp. Por causa da presença desses patógenos, essa água não é adequada para qualquer uso doméstico e de irrigação. O estudo revelou que a água do Canal Lahore é prejudicial à saúde humana, pois está contaminada com bactérias que podem causar doenças graves, por exemplo: Escherichia coli pode ocasionar gastroenterite; Bacillus spp. pode causar náuseas e vômitos; Enterococcus sp. pode infectar o trato urinário; Salmonella sp. é responsável pela bacteremia; Staphylococcus spp. pode causar febre leve; e Vibrio sp. pode ser a razão da cólera. Assim, torna-se imprópria para uso humano, como natação, banho, lavagem etc., até que algumas medidas corretivas sejam empregadas para erradicar microrganismos patogênicos por WASA e LWMS de acordo com os padrões da OMS. Da mesma forma, é bastante prejudicial, quando usada para irrigação sem tratamento adequado.


Assuntos
Animais , Solo , Staphylococcus , Vibrio , Resistência Microbiana a Medicamentos , Amostras de Água , Enterococcus , Escherichia coli
2.
J Ethnopharmacol ; 318(Pt A): 116806, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37460028

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Diarrhea is a frequently encountered gastrointestinal complication in clinical practice, and E. coli is one of the main causative agents. Although Qingjie decoction (QJD) has been shown to be highly effective in treating diarrhea by eliminating heat-toxin, the underlying molecular mechanisms and pathways of QJD remain unclear. AIM OF REVIEW: The aim of this research was to explore the effects and fundamental mechanism of QJD on diarrhea induced by E.coli in rats. MATERIALS AND METHODS: Initially, we used UHPLC-MS/MS analysis to identify the chemical composition of QJD. Then, we constructed a visualization network using network pharmacology. Next, we utilized metabolomics to identify differentially expressed metabolites of QJD that are effective in treating diarrhea. RESULTS: The chemical composition of QJD was analyzed using UHPLC-MS/MS, which identified a total of 292 components. Using a network pharmacology approach, 127 bioactive compounds of QJD were screened, targeting 171 potential diarrhea treatment targets. TNF-α, IL-6, IL-1ß, and CAT were identified as important targets through visualizing the PPI network. Enrichment analysis demonstrated significant enrichment in the TNF signaling pathway, IL-17 signaling pathway, and PI3K-Akt signaling pathway. QJD showed beneficial effects, such as increased body weight, decreased fecal water content, and reduced inflammatory cell infiltration in the duodenum and colon, as well as maintaining the structure of the duodenum and colon. Metabolomic analysis revealed 32 differentially expressed metabolites in the control, model and QJD-H groups, including glucose, valine, and cysteine. Functional analysis indicated that differential metabolites were related to energy metabolism, including glucose metabolism, TCA cycle, and amino acid metabolism. CONCLUSION: QJD significantly increased body weight, decreased water content in feces, relieved inflammatory cell infiltration, maintained the structure of duodenum and colon. Combining network analysis and metabolomics, QJD exerted therapeutic effects by inhibiting inflammation and oxidative stress, regulating glucose metabolism, tricarboxylic acid metabolism, and amino acid metabolism.


Assuntos
Besouros , Medicamentos de Ervas Chinesas , Animais , Ratos , Escherichia coli , Fosfatidilinositol 3-Quinases , Espectrometria de Massas em Tandem , Metabolômica , Metabolismo Energético , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Cisteína , Glucose , Inflamação , Peso Corporal , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
3.
Food Chem ; 432: 137187, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37625297

RESUMO

Natural preservatives are causing a rethinking of current preservation means. As a sweetener resource, exploitation of Stevia rebaudiana leaves (SRLs) is still restricted due to human conventional cognition. Herein, Lactobacillus plantarum fermented SRLs containing diverse free secondary metabolites derived from microbial deglycosylation and bioenzymatic decomposition were investigated. The apparent resistance to typical foodborne bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Pseudomoas aeruginosa, Bacillus amyloliquefaciens) by fermented SRLs and their extracts were validated. The metabolite diversity and in-depth organic solvent extraction gave the possibilities for better antimicrobial actions, anti-HepG2/SGC-7901 cells in vitro in contrast with aqueous extract of unfermented SRLs. Crucially, compound identification and attribution revealed that fermentation products may be maximally contributing to antimicrobial and antitumor mechanisms rather than intrinsic plant and/or microbial components. Additionally, pork sausage models with 15 g/kg ethyl acetate extract as a preservative candidate presented preferred storage characteristics (21 days and 37 °C) compared to those without ethyl acetate extract, e.g. the minimal total plate count (3.86 ± 0.27 log CFU/g), peroxsignide value (8.02 ± 0.92 meq/kg), and acid value (2.01 ± 0.04 (KOH)/(mg/g)).


Assuntos
Lactobacillus plantarum , Neoplasias , Stevia , Humanos , Conservantes Farmacêuticos , Linhagem Celular , Escherichia coli
4.
Food Chem ; 432: 137215, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37633134

RESUMO

Carrageenan-based active/intelligent packaging films containing anthocyanin and ZnO-doped CD (Zn-CD) from purple Kohlrabi peels were prepared for freshness monitoring and shelf-life extension of shrimp, and the influence of additives on the films' physical, functional, and structural properties was investigated. The films showed excellent UV blocking ability (85.2% of UV-A and 99.4% of UV-B) and high antioxidant effect (∼99% for ABTS and âˆ¼ 58.6% for DPPH radical scavenging activity) and showed strong antibacterial activity to stop the growth (100%) of L. monocytogenes and to reduce the growth of E. coli by 8.1 log CFU/mL after 12 h of incubation. In shrimp packaging experiments, the films were evident in the freshness monitoring, reduced spoilage, and increased shelf life. This study suggests that next-generation biopolymer films impregnated with biomass-derived CDs and natural colorants will provide broad directions for ensuring safety and extending shelf life to meet the accelerating demand for packaging products.


Assuntos
Antocianinas , Decápodes , Animais , Carragenina , Escherichia coli , Crustáceos , Carbono , Zinco
5.
Food Chem ; 432: 137202, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37634342

RESUMO

The pequi (Caryocar brasiliense) external mesocarp is rich in phenolic compounds and pectin and demonstrates the potential to produce active and biodegradable films. Thus, the present study aimed to produce films with pequi mesocarp as a polymer matrix and evaluate the influence of crosslinking agents (calcium chloride and citric acid) on the film's properties. The films obtained from pequi mesocarp (MF), showed in general, complete biodegradation in 33 days, good antioxidant capacity, and inhibition against S. aureus (24.7 mm) and E. coli (23.0 mm). The crosslinking agents reduced solubility by up to 35% and increased the elongation of the films by up to 3.5-fold. Calcium chloride promoted a higher reduction in solubility, and both agents increase the antioxidant and antimicrobial activities, compared to MF. Citric acid proved to be the best agent to modify the properties of pequi mesocarp films. In addition to the crosslinking action, it presented plasticizing effect.


Assuntos
Antioxidantes , Malpighiales , Antioxidantes/farmacologia , Cloreto de Cálcio , Escherichia coli , Staphylococcus aureus , Ácido Cítrico
6.
Food Chem ; 432: 137258, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37657339

RESUMO

Polyphenol oxidase (PPO) plays a critical role in decrement of shrimp quality. To obtain active PPO and elucidate its enzymatic properties, PPO from Litopenaeus vannamei (Lv-PPO) was cloned, expressed in E. coli and purified by affinity column chromatography. The Lv-PPO gene was 2076 bp in length encoding 691 amino acids. The recombinant Lv-PPO (rLv-PPO) with a molecular mass of ∼85.0 kDa was successfully expressed and its sequence was verified by LC-MS/MS. rLv-PPO was biologically active with an optimal temperature of 40℃ and an optimal pH of 6.0. Metal ions Cu2+ and Zn2+ altered the activity of rLv-PPO by influencing its secondary and tertiary structures. rLv-PPO showed catalytic activity towards l-Dopa and catechol. A specific polyclonal antibody against rLv-PPO was prepared. Western blot analysis revealed that PPO levels were highest in hemolymph, followed by telson, carapace, and eyestalk. Expression of rLv-PPO will assist future studies on the mechanism in shrimp melanosis.


Assuntos
Escherichia coli , Penaeidae , Animais , Cromatografia Líquida , Espectrometria de Massas em Tandem , Penaeidae/genética , Anticorpos , Catecol Oxidase/genética
7.
Food Chem ; 432: 137203, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37659328

RESUMO

Recently, intelligent packaging has combined several functions, including monitoring and preserving food freshness in real-time. This study was developed a hybrid film (active/ colorimetric) based on AM/CPC/9%SFW as a carrier of Origanum compactum essential oil (OC) in various concentrations (0%, 1%, 1.25%, and 1.5% v/v). The film's emulsions showed homogeneity regarding particle size, polydispersity index, and ζ -potential. Hybrid films' morphological, mechanical, water and light barrier, thermal, and antioxidant properties were enhanced with an increased OC. Interestingly, all films rapidly responded to pH/NH3 and reflected different colors. In the hybrid films, an inhibition effect against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria and OC (1.5%) film exhibited a large inhibition zone attained diameters of 37.33 and 15.67 mm, respectively, in the disc diffusion test. Outstanding, AM/CPC/9%SFW/1.5 %OC film displayed the ability to preserve and monitor chicken breast and shrimp freshness to 33 and 21 h, respectively, during storage at 25 °C.


Assuntos
Óleos Voláteis , Origanum , Animais , Galinhas , Colorimetria , Alimentos Marinhos , Antibacterianos/farmacologia , Crustáceos , Escherichia coli , Óleos Voláteis/farmacologia
8.
Talanta ; 266(Pt 2): 125101, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37651907

RESUMO

Bacterial infections can significantly impair wound healing. Therefore, it is essential to develop wound dressings with high antimicrobial activity. Hydrogels are often used as wound dressings due to their excellent physicochemical properties. Herein, by cross linking sodium alginate (SA), agar (AG) with Ti3C2Tx MXene and Zinc ions (Zn2+), a biosafe composite hydrogel (MSG-Zn2+) was developed for fast and efficient sterilization treatment. The excellent photothermal properties of Ti3C2Tx MXene and the chemical antimicrobial activity of Zn2+ enable synergistic photothermal therapy (PTT)/chemical therapy in NIR biowindow with reduced power density and improved antimicrobial efficiency. More importantly, the incorporation of Zn2+ can enhance the effective contact between the hydrogel and bacteria, benefiting both photothermal and chemical antibacteria. In vitro antibacterial experiments showed that MSG-Zn2+ has a broad-spectrum antibacterial effect against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). Cellular experiments showed that the hydrogel had excellent biocompatibility and the released Zn2+ stimulated cell migration. In addition, the prepared MSG-Zn2+ hydrogel has other advantages such as hydrophilic, high swelling, simple and low cost preparation, which meets the requirements of an economical wound dressing. This proposed work shows that this composite hydrogel MSG-Zn2+ has great potential for practical antimicrobial wound dressing applications.


Assuntos
Hidrogéis , Zinco , Ágar , Hidrogéis/farmacologia , Zinco/farmacologia , Escherichia coli , Staphylococcus aureus , Esterilização , Antibacterianos/farmacologia , Alginatos/farmacologia
9.
Braz. j. biol ; 84: e255755, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355898

RESUMO

Abstract The present study involves the chemical and bacteriological analysis of water from different sources i.e., bore, wells, bottle, and tap, from Peshawar, Mardan, Swat and Kohat districts of Khyber Pakhtunkhwa (KP) province, Pakistan. From each district, 50 water samples (10 samples from each source), regardless of urban and rural status, were collected from these sources and analysed for sulphates, nitrates, nitrites, chlorides, total soluble solids and coliforms (E. coli). Results indicated that majority of the water sources had unacceptable E. coli count i.e.> 34 CFU/100mL. E. coli positive samples were high in Mardan District, followed by Kohat, Swat and Peshawar district. Besides this, the some water sources were also chemically contaminated by different inorganic fertilizers (nitrates/nitrites of sodium, potassium) but under safe levels whereas agricultural and industrial wastes (chloride and sulphate compounds) were in unsafe range. Among all districts, the water quality was found comparatively more deteriorated in Kohat and Mardan districts than Peshawar and Swat districts. Such chemically and bacteriologically unfit water sources for drinking and can cause human health problems.


Resumo O presente estudo envolve a análise química e bacteriológica de água de diferentes fontes, ou seja, furo, poços, garrafa e torneira, dos distritos de Peshawar, Mardan, Swat e Kohat da província de Khyber Pakhtunkhwa (KP), Paquistão. De cada distrito, 50 amostras de água (10 amostras de cada fonte), independentemente do status urbano e rural, foram coletadas dessas fontes e analisadas para sulfatos, nitratos, nitritos, cloretos, sólidos solúveis totais e coliformes (E. coli). Os resultados indicaram que a maioria das fontes de água tinha uma contagem inaceitável de E. coli, ou seja, > 34 UFC / 100 mL. As amostras positivas para E. coli foram elevadas no distrito de Mardan, seguido por Kohat, Swat e distrito de Peshawar. Além disso, algumas fontes de água também foram contaminadas quimicamente por diferentes fertilizantes inorgânicos (nitratos/nitritos de sódio, potássio), mas em níveis seguros, enquanto os resíduos agrícolas e industriais (compostos de cloreto e sulfato) estavam em níveis inseguros. Entre todos os distritos, a qualidade da água foi considerada comparativamente mais deteriorada nos distritos de Kohat e Mardan do que nos distritos de Peshawar e Swat. Essas fontes de água química e bacteriologicamente impróprias para beber podem causar problemas à saúde humana.


Assuntos
Humanos , Água Potável , Qualidade da Água , Paquistão , Escherichia coli
10.
Food Chem ; 430: 137075, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549618

RESUMO

The very first time, whey protein from the Himalayan goat breed "Gaddi" was hydrolyzed with alcalase, flavourzyme, and a combination of both in this study. The degree of hydrolysis (DH) ranged from 28 to 53%, with sequential hydrolysis by combination achieving the highest DH. The sequential hydrolysis demonstrated antimicrobial activity against all pathogens used with 3 kDa permeate showed significantly higher (p < 0.05) activity against S. aureus, E. coli, B. cereus and C. sakazakii. The antioxidant activity was in the range of IC50 = 0.49 to 2.00 mg protein/mL, flavourzyme and sequential hydrolysates showed significant ABTS radical and FRAP inhibition. The α-amylase inhibitory activity was highest in 3 kDa permeate of flavourzyme with IC50 values of 0.34 mg protein/mL. Bioactive peptides DDSPDLPK, EMPFPK and TPEVDKEALEK were identified most significant in the hydrolysates. In molecular docking, the DDSPDLPK interacted most efficiently with enzymes involved in microbial growth, oxidative stress, and hyperglycemia.


Assuntos
Cabras , Soro do Leite , Animais , Proteínas do Soro do Leite , Simulação de Acoplamento Molecular , Escherichia coli , Proteômica , Staphylococcus aureus , Melhoramento Vegetal , Peptídeos/química , Hidrólise , Hidrolisados de Proteína/química
11.
NPJ Syst Biol Appl ; 9(1): 44, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730753

RESUMO

Ribosomes which can self-replicate themselves practically autonomously in beneficial physicochemical conditions have been recognized as the central organelles of cellular self-reproduction processes. The challenge of cell design is to understand and describe the rates and mechanisms of self-reproduction processes of cells as of coordinated functioning of ribosomes and the enzymatic networks of different functional complexity that support those ribosomes. We show that doubling times of proto-cells (ranging from simplest replicators up to those reaching the size of E. coli) increase rather with the number of different cell component species than with the total numbers of cell components. However, certain differences were observed between cell components in increasing the doubling times depending on the types of relationships between those cell components and ribosomes. Theoretical limits of doubling times of the self-reproducing proto-cells determined by the molecular parameters of cell components and cell processes were in the range between 6-40 min.


Assuntos
Escherichia coli , Ribossomos , Reprodução
12.
Sci Rep ; 13(1): 15605, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37731031

RESUMO

On the global market, silver nanoparticles (Ag-NPs) are in high demand for their various applications in biomedicine, material engineering, and consumer products. This study highlighted the biosynthesis of the Ag-NPs using saw palmetto seed phenolic extract (SPS-phenolic extract), which contained vital antioxidant-phenolic compounds. Herein, central composite statistical design, response surface methodology, and sixteen runs were conducted to optimize Ag-NPs biosynthesis conditions for maximizing the production of Ag-NPs and their phenolic content. The best-produced SPS-Ag-NPs showed a surface plasmon resonance peak at 460 nm and nano-spherical sizes ranging from 11.17 to 38.32 nm using the UV spectrum analysis and TEM images, respectively. The produced SPS-Ag-NPs displayed a high negative zeta-potential value (- 32.8 mV) demonstrating their high stability. The FTIR analysis demonstrated that SPS-phenolic compounds were involved in sliver bio-reduction and in stabilizing, capping, and preventing Ag-NP aggregation. The thermogravimetric investigation revealed that the produced SPS-Ag-NPs have remarkable thermal stability. The produced SPS-Ag-NP exceeded total antioxidant activity (13.8 µmol Trolox equivalent) more than the SPS-phenolic extract (12.0 µmol Trolox equivalent). The biosynthesized SPS-Ag-NPs exhibited noticeably better antibacterial activity against multidrug-resistant Gram-negative E. coli and Gram-positive S. aureus compared to SPS-phenolic extract. Hence, the bio-synthesized SPS-Ag-NPs demonstrated great potential for use in biomedical and antimicrobial applications.


Assuntos
Antioxidantes , Nanopartículas Metálicas , Antioxidantes/farmacologia , Prata , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Fenóis , Sementes
13.
Mikrochim Acta ; 190(10): 407, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37731054

RESUMO

A superior photoelectrochemical (PEC) aptasensor was manufactured for the detection of Escherichia coli (E. coli) based on a hybrid of triazine-based covalent-organic framework (COF) and cuprous oxide (Cu2O). The COF synthesized using 1,3,5-tris(4-aminophenyl)-benzene (TAPB) and 1,3,5-triformylphloroglucinol (Tp) as building blocks acted as a scaffold for encapsulated Cu2O nanoparticles (denoted as Cu2O@TAPB-Tp-COF), which then was employed as the bioplatform for anchoring E. coli-targeted aptamer. Cu2O@Cu@TAPB-Tp-COF demonstrated enhanced separation of the photogenerated carriers and photoabsorption ability and boosted photoelectric conversion efficiency. The developed Cu2O@TAPB-Tp-COF-based PEC aptasensor exhibited a lower detection limit of 2.5 CFU mL-1 toward E. coli within a wider range of 10 CFU mL-1 to 1 × 104 CFU mL-1 than most of reported aptasensors for determining foodborne bacteria, together with high selectivity, good stability, and superior ability and reproducibility. The recoveries of E. coli spiked into milk and bread samples ranged within 95.3-103.6% and 96.6-102.8%, accompanying with low RSDs of 1.37-4.48% and 1.74-3.66%, respectively. The present study shows a promising alternative for the sensitive detection of foodborne bacteria from complex foodstuffs and pathogenic bacteria-polluted environment.


Assuntos
Escherichia coli , Estruturas Metalorgânicas , Reprodutibilidade dos Testes , Benzamidinas
14.
Front Cell Infect Microbiol ; 13: 1253095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731820

RESUMO

Purpose: The current study aimed to develop a topical herbal emulgel containing Carthamus tinctorius L. (CT) oil extract, which has been scientifically proven for its antibacterial and antioxidant activities for the ailment of bacterial skin infections. Method: The CT emulgel was formulated by response surface methodology (RSM) and was evaluated by various parameters like extrudability, spreadability, pH, viscosity, and antibacterial and antioxidant activities. Molecular docking was also performed using AutoDock. Results: Among all formulated CT emulgels, F9 and F8 were optimized. Optimized formulations had shown good spreadability and extrudability characteristics. Sample F8 had % inhibition of 42.131 ± 0.335, 56.720 ± 0.222, and 72.440 ± 0.335 at different concentrations. Sample F9 had % inhibition of 26.312 ± 0.280, 32.461 ± 0.328, and 42.762 ± 0.398 at concentrations of 250 µg/ml, 500 µg/ml, and 1,000 µg/ml, respectively, which shows that both samples F8 and F9 have significant antioxidant potential. Optimized CT emulgels F8 and F9 had significant antibacterial activity against Staphylococcus aureus and Escherichia coli at p-value = 0.00, the Emulgel-F8 shows zone of inhibition of 24 mm for E-coli and 19 mm for S-aureus. Emulgel-F9 shows zone of inhibition of 22 mm for E-coli and 15 mm for S-aureus while pure CT- Oil extract shows zone of inhibition of 25 mm for E-coli and 20 mm for S-aureus and ciprofloxacin used as standard shows 36mm zone of inhibition against both E-coli and S-aureus. The comparative investigation through molecular docking binding affinities and interactions of ligands with various target proteins provides insights into the molecular processes behind ligand binding and may have significance for drug discovery and design for the current study. Conclusion: The current study suggests that C. tinctorius L.-based emulgel has good antioxidant and antibacterial activities against E. coli for the treatment of bacterial skin infections.


Assuntos
Carthamus tinctorius , Dermatopatias Bacterianas , Antioxidantes/farmacologia , Escherichia coli , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Staphylococcus aureus , Extratos Vegetais/farmacologia
15.
ACS Chem Biol ; 18(9): 2063-2072, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37671702

RESUMO

The bacterial cell envelope provides a protective barrier that is challenging for small molecules and biomolecules to cross. Given the anionic nature of both Gram-positive and Gram-negative bacterial cell envelopes, negatively charged molecules are particularly difficult to deliver into these organisms. Many strategies have been employed to penetrate bacteria, ranging from reagents such as cell-penetrating peptides, enzymes, and metal-chelating compounds to physical perturbations. While cationic polymers are known antimicrobial agents, polymers that promote the permeabilization of bacterial cells without causing high levels of toxicity and cell lysis have not yet been described. Here, we investigate four polymers that display a cationic poly(2-(dimethylamino)ethyl methacrylate (D) block for the internalization of an anionic adenosine triphosphate (ATP)-based chemical probe into Escherichia coli and Bacillus subtilis. We evaluated two polymer architectures, linear and micellar, to determine how shape and hydrophobicity affect internalization efficiency. We found that, in addition to these reagents successfully promoting probe internalization, the probe-labeled cells were able to continue to grow and divide. The micellar structures in particular were highly effective for the delivery of the negatively charged chemical probe. Finally, we demonstrated that these cationic polymers could act as general permeabilization reagents, promoting the entry of other molecules, such as antibiotics.


Assuntos
Trifosfato de Adenosina , Antibacterianos , Antibacterianos/farmacologia , Bacillus subtilis , Cátions , Morte Celular , Escherichia coli
16.
ACS Appl Mater Interfaces ; 15(37): 43332-43344, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37671841

RESUMO

Cystinuria is an inherited autosomal recessive disease of the kidneys of recurring nature that contributes to frequent urinary tract infections due to bacterial growth and biofilm formation surrounding the stone microenvironment. In the past, commonly used strategies for managing cystinuria involved the use of (a) cystine crystal growth inhibitors such as l-cystine dimethyl ester and lipoic acid, and (b) thiol-based small molecules such as N-(2-mercaptopropionyl) glycine, commonly known as tiopronin, that reduce the formation of cystine crystals by reacting with excess cystine and generating more soluble disulfide compounds. However, there is a dearth of simplistic chemical approaches that have focused on the dual treatment of cystinuria and the associated microbial infections. This work strategically exploited a single chemical approach to develop a nitric oxide (NO)-releasing therapeutic compound, S-nitroso-2-mercaptopropionyl glycine (tiopronin-NO), for the dual management of cystine stone formation and the related bacterial infections. The results successfully demonstrated that (a) the antibacterial activity of NO rendered tiopronin-NO effective against the stone microenvironment inhabitants, Escherichia coli and Pseudomonas aeruginosa, and (b) tiopronin-NO retained the ability to undergo disulfide exchange with cystine while being reported to be safe against canine kidney and mouse fibroblast cells. Thus, the synthesis of such a facile molecule aimed at the dual management of cystinuria and related infections is unprecedented in the literature.


Assuntos
Infecções Bacterianas , Cistinúria , Camundongos , Animais , Cães , Cistinúria/tratamento farmacológico , Tiopronina/farmacologia , Tiopronina/uso terapêutico , Cistina/farmacologia , Dissulfetos , Escherichia coli , Óxido Nítrico
17.
ACS Appl Mater Interfaces ; 15(37): 43550-43562, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37672350

RESUMO

The high temperature induced by surgical electrodes is highly susceptible to severe surface adhesion and thermal damage to adjacent tissues, which is a major challenge in improving the quality of electrosurgery. Herein, we reported a coupled electrode with micro/nano hierarchical structures fabricated by depositing nanoscale hafnium oxide (HfO2) coatings on bionic microstructures (BMs) via laser texturing, acid washing, and atomic layer deposition (ALD) techniques. The synergistic effect of HfO2 coatings and BMs greatly enhanced the hemophobicity of the electrode with a blood contact angle of 162.15 ± 3.16°. Furthermore, the coupled surface was proven to have excellent antiadhesive properties to blood when heated above 100 °C, and the underlying mechanism was discussed. Further experiments showed that the coupled electrode had significant advantages in reducing cutting forces, thermal damage, and tissue adhesion mass. Moreover, the antibacterial rates against Escherichia coli and Staphylococcus aureus were 97.2% and 97.9%, respectively. In addition, the noncytotoxicity levels of HfO2 coatings were verified by cell apoptosis and cycle assays, indirectly endowing the coupled electrode with biocompatibility. Overall, the coupled electrode was shown to have broad potential for application in the field of electrosurgery, and this work could provide new insights into antiadhesion properties under high-temperature conditions.


Assuntos
Biônica , Eletrocirurgia , Antibacterianos/farmacologia , Apoptose , Eletrodos , Escherichia coli , Excipientes
18.
Nat Commun ; 14(1): 5464, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673860

RESUMO

The abuse of antibiotics has led to the emergence of multidrug-resistant microbial pathogens, presenting a pressing challenge in global healthcare. Membrane-disrupting antimicrobial peptides (AMPs) combat so-called superbugs via mechanisms different than conventional antibiotics and have good application prospects in medicine, agriculture, and the food industry. However, the mechanism-of-action of AMPs has not been fully characterized at the cellular level due to a lack of high-resolution imaging technologies that can capture cellular-membrane disruption events in the hydrated state. Previously, we reported PepD2M, a de novo-designed AMP with potent and wide-spectrum bactericidal and fungicidal activity. In this study, we use cryo-electron tomography (cryo-ET) and high-speed atomic force microscopy (HS-AFM) to directly visualize the pepD2M-induced disruption of the outer and inner membranes of the Gram-negative bacterium Escherichia coli, and compared with a well-known pore-forming peptide, melittin. Our high-resolution cryo-ET images reveal how pepD2M disrupts the E. coli membrane using a carpet/detergent-like mechanism. Our studies reveal the direct membrane-disrupting consequence of AMPs on the bacterial membrane by cryo-ET, and this information provides critical insights into the mechanisms of this class of antimicrobial agents.


Assuntos
Peptídeos Antimicrobianos , Tomografia com Microscopia Eletrônica , Escherichia coli , Fenômenos Fisiológicos Celulares , Antibacterianos/farmacologia
19.
BMC Infect Dis ; 23(1): 582, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37674127

RESUMO

BACKGROUND: Urinary tract infection (UTI) is considered one of the most prevalent infections that may lead to many renal complications. They account for almost 10% of all infections in Saudi Arabia, making them the second most common cause of emergency department admissions. Bacterial pathogens, primarily Escherichia coli, Klebsiella spp., Enterococcus spp., Proteus spp., and Staphylococcus spp. are the most causative agents of UTI. This study aims to evaluate the prevalence and antimicrobial susceptibility patterns of uropathogens in adult patients from Madinah, Saudi Arabia. METHODS: A retrospective cross-sectional study was performed using data collected from patients who visited King Fahad General Hospital in Madinah, Saudi Arabia. Data included 16,803 urine bacterial cultures and their antimicrobial susceptibility profiles collected between January 2019 and October 2021. RESULTS: Among the 16,803 tested samples, 3937 (23.4%) showed positive results for urine bacterial cultures. UTI prevalence was slightly higher in women (52.1%) than men (47.9%). Escherichia coli (29.8%) was the most prevalent, followed by Klebsiella spp. (23.2%) and Pseudomonas spp. (8.4%). As for Gram-positive bacteria, Enterococcus spp. (10.8%) were most common, followed by Streptococcus spp. (8%) and Staphylococcus spp. (3.3%). Gram-negative bacteria exhibited high resistance rates toward aztreonam (> 83.3%), ampicillin (78.8%), and cephalexin (68.5%). Enterococcus spp. displayed elevated resistance rates (> 62.3%) against ciprofloxacin, gentamicin, and tetracycline. Conversely, Streptococcus spp. showed substantial resistance rates (> 76.6%) toward colistin and trimethoprim/sulfamethoxazole. CONCLUSION: To optimize therapy and minimize the risk of multidrug-resistant uropathogenic infections, physicians should consider the local epidemiological trends and antimicrobial resistance patterns of prevalent uropathogens prior to initiating any empirical antibacterial therapy.


Assuntos
Antibacterianos , Enterococcus , Masculino , Humanos , Adulto , Feminino , Arábia Saudita/epidemiologia , Estudos Transversais , Prevalência , Estudos Retrospectivos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Escherichia coli
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