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1.
Braz J Microbiol ; 54(3): 2205-2218, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37526891

RESUMO

Antimicrobial resistance among bacteria present in ready-to-eat foods is an emerging concern. Hence, this study investigated the presence of extended-spectrum and AmpC ß-lactamases (ESBL/AmpC)-producing Enterobacterales (ESBL-E) and the dissemination of mcr-1 in ESBL-E from ready-to-eat food samples (RTE) in Algeria. RTE food samples (n = 204) were aseptically collected and selectively cultured using MacConkey agar. The isolates were screened for ESBL production using the DDST test, confirmed ESBL-E isolates were identified using different conventional methods and MALDI-TOF MS, antibiotic susceptibility was determined using the disc diffusion and broth microdilution assay, ESBL-E isolates were analyzed for colistin and ESBL/AmpC encoding genes by PCR, and food samples were analyzed by univariate and multiple logistic regression. Overall, 48 (17.4%) of the 276 Enterobacterales were confirmed as ESBL producers, with a high prevalence in soups (40%), salads (25%), and cream-filled pastries (23.8%). Antibiotic susceptibility testing revealed that all the ESBL-E isolates were found multi-drug resistant. PCR revealed that blaTEM, blaCTX-M, blaCMY-2, blaOXA-1, and blaSHV were the most frequently detected. blaCTX-M-9 and blaCTX-M-1 were the predominant CTX-M types. Furthermore, four isolates were positive for mcr-1; three of them harbored the colistin resistance gene and ESBL/AmpC genes (2 E. cloacae and 1 S. enterica). To the best of our knowledge, this is the first report that detects the presence of the mcr-1 gene in ESBL-E strains isolated from RTE foods in Algeria. These findings suggest an urgent need for strict policies that prevent the spread and transmission of ESBL-E in food.


Assuntos
Colistina , Infecções por Escherichia coli , Humanos , Colistina/farmacologia , Escherichia coli/genética , Antibacterianos/farmacologia , Infecções por Escherichia coli/microbiologia , Prevalência , Argélia , beta-Lactamases/genética
3.
Biomed Res Int ; 2018: 7295848, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29744362

RESUMO

Over the last few decades, Rumex species have been recognized as a promising source of new compounds with numerous pharmacological activities. Therefore, the antioxidant activity of Rumex tingitanus (R. tingitanus) leaves extracts was evaluated in vitro and then confirmed in vivo as well as the antidepressant-like and toxicological effects of the extracts. The ethyl acetate fraction (Rt EtOAcF) followed by hydroalcoholic extract (Rt EtOH-H2O) showed a remarkable in vitro antioxidant activity. The hydroalcoholic extract (Rt EtOH-H2O) showed significant hepatoprotective activity against carbon tetrachloride- (CCl4-) induced liver toxicity which is seen from inhibition of the malondialdehyde (MDA) accumulation and enhancement of the liver antioxidant enzymes activities. The Rt EtOH-H2O and Rt EtOAcF extracts were able to reduce the immobility time in mice and then elicited a significant antidepressant-like effect. The ethyl acetate fraction (Rt EtOAcF) was purified and resulted in the identification of a new antioxidant component called 4'-p-acetylcoumaroyl luteolin. The Rt EtOAcF and the 4'-p-acetylcoumaroyl luteolin revealed a strong antioxidant activity using DPPH test with IC50 of 11.7 ± 0.2 and 20.74 ± 0.6 µg/ml, respectively, and AAI of 3.39 and 1.92 better than that of BHT, used as control.


Assuntos
Antioxidantes/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Rumex/química , Animais , Antidepressivos/administração & dosagem , Antidepressivos/química , Antioxidantes/química , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Humanos , Camundongos , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química
4.
Microb Drug Resist ; 24(4): 461-468, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29022829

RESUMO

The emergence of carbapenemase-producing Enterobacteriaceae is of great concern to public health worldwide. The aim of this study was to screen for the presence of carbapenemase-producing Enterobacteriaceae in white stork (Ciconia ciconia) migratory bird stools, and to investigate their molecular support on ß-lactamase production. In March 2015, 32 fecal samples of white stork were collected in the Commune of El Madher Wilaya de Batna, in eastern Algeria. Samples were subjected to selective isolation of carbapenem-resistant Enterobacteriaceae. Representative colonies were screened phenotypically for carbapenemase production. Carbapenemase-producing isolates were subjected to antibiotic susceptibility testing and extended-spectrum ß-lactamase (ESBL) coproduction. ß-Lactamase determinants were searched for by PCR and sequencing. Three carbapenemase-producing Escherichia coli were obtained. Only one strain was positive for ESBL production. The OXA-48-type carbapenemase-encoding gene was detected in all isolates. Screening for other ß-lactamase-encoding genes showed that all isolates coexpress the blaTEM gene, whereas one of them additionally harbored the blaCTX-M-15 ESBL gene. Multilocus sequence typing results showed that two strains belonged to the sequence type 38. This work demonstrated for the first time that the migratory white stork can play an important role in the dissemination of OXA-48-producing E. coli as a potential reservoir and vector.


Assuntos
Aves/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Argélia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriaceae/genética , Fezes/microbiologia , Testes de Sensibilidade Microbiana/métodos , Tipagem de Sequências Multilocus/métodos , beta-Lactamases/genética
5.
Meat Sci ; 125: 22-29, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27883958

RESUMO

This study was undertaken to investigate the antibacterial and antifungal activities of Rumex tingitanus leaves extracts as well as the identification of bioactive components and their performance in meat preservation. Total phenolics and flavonoids showed the highest content of phenolics and flavonoids in the ethyl acetate fraction (Rt EtOAcF). For antimicrobial efficacy, leaves extract and derived fraction were tested for their capacity to inhibit bacterial and fungal proliferation in vitro and in vivo. The ethyl acetate fraction showed the most potent antibacterial and antifungal activities compared to the others extracts. Thus, the efficacy of this extract to inhibit the proliferation of Listeria monocytogenes in minced beef meat model was examined. This fraction eradicates the L. monocytogenes population in meat in a concentration- and time-dependent manner. A bio-guided purification of the Rt EtOAc fraction resulted in the isolation of the compound responsible for the observed antimicrobial activity. This compound was identified as luteolin by analysis of spectroscopic data. CHEMICAL COMPOUNDS ISOLATED IN THIS ARTICLE: Luteolin (PubChem CID: 5280445); p-iodonitrotetrazolium chloride (PubChem CID: 64957); Amphotericin B (PubChem CID: 5280965); Gentamicin and (PubChem CID: 6419933); Hexane (PubChem CID: 8058); Methanol (PubChem CID: 887); Ethanol (PubChem CID: 702); Dimethylsulfoxide (PubChem CID: 679); Quercetin (PubChem CID: 5280343); Gallic acid (PubChem CID: 370).


Assuntos
Anti-Infecciosos/farmacologia , Conservantes de Alimentos/farmacologia , Carne/microbiologia , Extratos Vegetais/farmacologia , Rumex/química , Alternaria/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Fracionamento Químico , Flavonoides/farmacologia , Contaminação de Alimentos , Microbiologia de Alimentos , Conservação de Alimentos , Fusarium/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Luteolina/farmacologia , Carne/análise , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Folhas de Planta/química , Taninos/farmacologia
6.
Molecules ; 20(8): 14902-14, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26287146

RESUMO

A broad biological screening of the natural alkaloid N-methylisosalsoline (2) extracted from Hammada scoparia leaves against a panel of human and parasitic proteases revealed an interesting activity profile of 2 towards human 20S proteasome. This outcome suggests that the 1,2,3,4-tetrahydroisoquinoline skeleton may be exploited as a template for the development of novel anticancer agents. In this article, we report the synthesis and chemical characterization of a new series of isosalsoline-type alkaloids (10-11) with variations at N2 and C3 positions with respect to the natural Compound 2, obtained by a synthetic strategy that involves the Bischler-Napieralski cyclization. The substrate for the condensation to the tetrahydroisoquinoline system, i.e., a functionalized ß-arylethyl amine, was obtained through an original double reduction of nitroalkene. The synthetic strategy can be directed to the construction of highly substituted and functionalized 1,2,3,4-tetrahydroisoquinolines.


Assuntos
Tetra-Hidroisoquinolinas/síntese química , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Humanos , Parasitos/efeitos dos fármacos , Parasitos/enzimologia , Peptídeo Hidrolases/metabolismo , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia
7.
Pharm Biol ; 53(12): 1810-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25885934

RESUMO

CONTEXT: Hepatic ischemia/reperfusion injury (IRI) is a major cause of liver damage during liver surgery and transplantation. Plants have historically been used in treating liver damage, and Hammada scoparia (Pomel) (Chenopodiaceae) has been reported to possess a broad spectrum of pharmacological and therapeutic activities. OBJECTIVE: In this study, a flavonoid-enriched fraction was used before the warm ischemia (WI) process as pharmacological preconditioning and in combination with technical postconditioning to evaluate their protective effects. MATERIALS AND METHODS: The rats were divided into five groups: a sham group; a control group (Control-IR) that was submitted to 60 min WI; a Pharmacological Preconditioning group (PreC-IR) that received flavonoid-enriched fraction (200 mg/kg body weight); a Postconditioning group (PostC) and a PreC + PostC group. RESULTS: The use of the flavonoid-enriched fraction was noted to significantly (p < 0.05) reduce liver injury, as evidenced by the decrease in liver transaminase activities (AST and ALT) and lactic dehydrogenase (LDH), alkaline phosphatase (ALP), and lipid peroxidation (TBARS), levels as well as the enhancement of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) responses. The results also indicated that, compared with the separate application of pharmacological preconditioning and postconditioning, the combination of both treatments was more effective in reducing tissue oxidative stress levels through modulating SOD, GSH-PX, and CAT activities. Furthermore, the combined protocol further decreased the liver morphological score compared with solo treatment. DISCUSSION AND CONCLUSION: Overall, the results indicate that the H. scoparia flavonoid-enriched fraction could be a promising candidate for future application as a pharmacological preconditioning agent against hepatic IRI.


Assuntos
Flavonoides/uso terapêutico , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Scoparia , Isquemia Quente/efeitos adversos , Animais , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Fígado/metabolismo , Masculino , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Resultado do Tratamento
8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1714, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21201700

RESUMO

THE TITLE COMPOUND (SYSTEMATIC NAME: 1,2-dimethyl-6-meth-oxy-1,2,3,4-tetra-hydro-isoquinolin-7-ol), C(12)H(17)NO(2), is a major alkaloid isolated from Hammada scoparia leaves. It belongs to the isoquinoline family and it was characterized by NMR spectroscopy and X-ray crystallographic techniques. The absolute configuration could not be reliably determined. An intermolecular O-H⋯N hydrogen bond is present in the crystal structure.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1739, 2008 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-21201722

RESUMO

THE TITLE COMPOUND (SYSTEMATIC NAME: 16-hydroxy-methyl-12-methoxy-ibogamine), C(21)H(28)N(2)O(2), was prepared by reaction of ibogaine with a formaldehyde-acetic acid solution (pH = 4). The crystal structure of this new product, belonging to the iboga indole family, is stabilized by an inter-molecular O-H⋯N hydrogen bond. The identity of the compound was confirmed by one- and two-dimensional NMR spectroscopic techniques.

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