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1.
Data Brief ; 51: 109664, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38075608

RESUMEN

A vancomycin-resistant Gram-positive bacterium of the genus Enterococcus, designated as BT22, was isolated from untreated hospital effluents at Chettia Chlef Hospital. The complete genome of strain BT22 was sequenced using the Illumina MiSeq platform, revealing a total length of 2,577,707 bp, with 2462 coding sequences (CDS) and an average G+C content of 38.00 mol%. Phylogenomic analyses confirmed that strain BT22 belongs to the same species as Enterococcus faecium AVS0243, with a similarity of 99.79 %. The study identified 12 antibiotic resistance genes and one virulence gene in strain BT22. These genes confer resistance to various classes of antibiotics, including aminoglycosides, macrolides, tetracyclines, and vancomycin. However, the virulence gene identified codes for adhesion. Furthermore, mobile genetic elements, such as IS elements carried by a conjugative plasmid, were detected. The genomic sequencing data of E. faecium BT22 will be of great value to the scientific community, enabling comparative genomic analyses and a better understanding of antibiotic resistance mechanisms, particularly towards vancomycin. The genomic information has been deposited in the DDBJ/EMBL/GenBank databases under accession number JASSVD010000000, providing an essential resource in the fight against antibiotic resistance and the spread of resistant bacterial strains.

2.
Chem Biodivers ; 19(9): e202200545, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35866461

RESUMEN

Plants constitute a valuable source of natural antioxidants such as polyphenols and are responsible for exhibiting many biologically significant functions. Ruta species including Ruta chalepensis L. and Ruta graveolens L. are widespread species in Algeria and are used as medicinal plants to treat various diseases; however, so far, most of the conducted studies focused on analyzing alkaloids and essential oils mostly on R. chalepensis. The aim of the present research is to investigate the phenolic profile of the aerial parts of Ruta graveolens L. from Algeria and assess its in vitro antioxidant, anti-inflammatory and antimicrobial properties. The total polyphenols and flavonoids were assessed using colorimetric methods, and the individual polyphenols were identified and quantified using HPLC-DAD-ESI-MS. The antioxidant activity was evaluated with DPPH and ß-carotene tests, and the anti-inflammatory activity with inhibition of bovine serum albumin denaturation and HRBC membrane stabilization methods. The results showed that Ruta graveolens extract is rich in phenolic compounds with a total phenol and flavonoid contents of 41.63±0.394 mg GAE/gE and 13.97±0.33 mg EQ/gE, respectively. Nine phenolic compounds were determined, including three phenolic acids and six flavonoids. Rutin was the major phenolic compound in Ruta graveolens (464.95 µg/g), followed by syringic acid (179.74 µg/g), and naringenin (109.78 µg/g). R. graveolens phenolic extract also showed good antioxidant activity with values of 0.77 mM TE/g DW and 0.37 mM ß-CE/g DW with DPPH and ß-carotene tests, respectively. For the anti-inflammatory activity, the highest tested concentration (200 µg/mL) gave 50.61 % of inhibition of the denaturation of albumin and 44.12 % of membrane stabilization. With regards to antimicrobial results, Staphylococcus aureus was the most sensitive bacteria with an inhibition zone of 14.37 mm and MIC value of 0.625 mg/mL, followed by Listeria monocytogenes (11.75 mm and MIC=1.25 mg/mL), and Escherichia coli (10.25 mm and MIC=1.25 mg/mL).


Asunto(s)
Alcaloides , Antiinfecciosos , Aceites Volátiles , Ruta , Argelia , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Flavonoides/farmacología , Aceites Volátiles/química , Fenoles/análisis , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polifenoles , Ruta/química , Rutina , Albúmina Sérica Bovina , beta Caroteno
3.
Molecules ; 26(12)2021 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-34199320

RESUMEN

Cucurbita moschata Duchesne (Cucurbitaceae) is a plant food highly appreciated for the content of nutrients and bioactive compounds, including polyphenols and carotenoids, which contribute to its antioxidant and antimicrobial capacities. The purpose of this study was to identify phenolic acids and flavonoids of Cucurbita moschata Duchesne using high-performance liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS) at different ripening stages (young, mature, ripened) and determine its antioxidant and antimicrobial activities. According to the results, phenolic acids and flavonoids were dependent on the maturity stage. The mature fruits contain the highest total phenolic and flavonoids contents (97.4 mg GAE. 100 g-1 and 28.6 mg QE. 100 g-1).A total of 33 compounds were identified. Syringic acid was the most abundant compound (37%), followed by cinnamic acid (12%) and protocatechuic acid (11%). Polyphenol extract of the mature fruits showed the highest antioxidant activity when measured by DPPH (0.065 µmol TE/g) and ABTS (0.074 µmol TE/g) assays. In the antimicrobial assay, the second stage of ripening had the highest antibacterial activity. Staphylococcus aureus was the most sensitive strain with an inhibition zone of 12 mm and a MIC of 0.75 mg L-1. The lowest inhibition zone was obtained with Salmonella typhimurium (5 mm), and the MIC value was 10 mg L-1.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión/métodos , Cucurbita/química , Frutas/química , Extractos Vegetales/química , Polifenoles/metabolismo , Antiinfecciosos/química , Antioxidantes/química , Cucurbita/metabolismo , Flavonoides/análisis , Flavonoides/metabolismo , Frutas/metabolismo , Polifenoles/análisis
4.
Curr Microbiol ; 74(11): 1253-1260, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28721659

RESUMEN

Antimicrobial activity of pepper polyphenols and capsaicinoids (Coumarin, caffeic acid, narangin, kaempferol, rutin, quercetin, capsaicin, and dihydrocapsaicin) against 13 pathogen bacteria and three beneficial strains was studied using the disk diffusion and microdilution methods. In general, phenolic compounds had the most important activity with the highest inhibition zones obtained with caffeic acid (3.5-20.5 mm), quercetin (4.75-3.5 mm), and kaempferol (7-14 mm). In the determination of the minimal inhibitory concentrations, the effects of both quercetin and kaempferol were more important than caffeic acid. The clinical strains Staphylococcus aureus (319, 14, 8, 32, and 550) were more sensitive to quercetin (0.00195-0.0078 mg L-1) whereas kaempferol was more active against the strains S. aureus (ATCC 6538, 26), S. typhimurium ATCC 13311, and Pseudomonas aeruginosa ATCC 27853 (0.0156-0.125 mg L-1). The interaction between these three polyphenols was studied against S. aureus ATCC 6538 and P. aeruginosa ATCC 27853. Different modes of interaction were observed (synergism, additive, and indifferent), but no antagonism was obtained. The best combination was quercetin and caffeic acid for S. aureus with fractional inhibitory concentration index (FICI) of 0.37, and kaempferol with quercetin for P. aeruginosa (FICI = 0.31).


Asunto(s)
Antiinfecciosos/farmacología , Capsaicina/farmacología , Capsicum/química , Extractos Vegetales/farmacología , Polifenoles/farmacología , Antiinfecciosos/química , Bacterias/efectos de los fármacos , Capsaicina/química , Pruebas Antimicrobianas de Difusión por Disco , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Polifenoles/química
5.
J Sep Sci ; 38(2): 171-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25378270

RESUMEN

The present study was aimed to investigate the polyphenolic profile of a pepper (Capsicum annuum L.) extract from Algeria and evaluate its biological activity. The total polyphenol content of the extract was determined as 1.373 mg of gallic acid equivalents (±0.0046), whereas the flavonoids were determined as 0.098 mg of quercetin (±0.0015). The determination of the complete polyphenolic profile of the extract was achieved by liquid chromatography with an RP-amide column in combination with photodiode array and mass spectrometry detection through an electrospray ionization interface. A total of 18 compounds were identified, of which five were reported for the first time in the sample tested. Quercetin rhamnoside was the most abundant compound (82.6 µg/g of fresh pepper) followed by quercetin glucoside (19.86 µg/g). The antioxidant activity and antimicrobial effects were also determined. For the antimicrobial tests assessed against Gram-positive and Gram-negative bacteria, kaempferol showed the strongest inhibitory effect followed by quercetin and caffeic acids. In the study of the cytotoxicity of the extract, the cancer cells (U937) were more affected than the normal cells (peripheral blood mononucleated cells), with more than 62% inhibition at the highest concentration.


Asunto(s)
Capsicum/química , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/química , Polifenoles/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Células U937
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