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1.
Heliyon ; 9(7): e18138, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37496903

RESUMO

Nowadays, coffee (Coffea Arabica L.) is among the most significant agricultural products of the world and drinking coffee has become one of the most popular habits in the world. The main contamination of stored coffee beans is related with the mycotoxin produced by the toxigenic fungi belonging the genus Aspergillus. Fungal infection followed by mycotoxin biosynthesis in coffee results in notable financial losses. subsequent mycotoxin biosynthesis in coffee leads to major economic losses. Complications ranging from mild to severe can be caused by the mycotoxins produced by this genus. The aim of this investigation was to determine the effect of menthol and eugenol on Aspergillus parasiticus (CBS 100926T) growth, spore germination, and their potential use as green coffee beans preservative during long-term storage (12 months). The minimum inhibitory concentrations (MICs) values of the menthol and eugenol were recorded to completely inhibit the growth of A. parasiticus in 400 µg/ml and 300 µg/ml, respectively. Both reduced spore germination by 9.33% and 5.66% at 300 µg/ml and 200 µg/ml, respectively. They showed efficacy in fumigated green coffee beans sample during the storage for up to 12 months providing an increase in the protection level of 62.5% for menthol and 73.21% for eugenol against the A. parasiticus contamination. This suggests that menthol and eugenol could be used as good alternatives for decreasing the deteriorations due to the fungal infections in green coffee beans during long-term storage.

2.
Molecules ; 28(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36903521

RESUMO

Centaurea parviflora (C. parviflora), belonging to the family Asteraceae, is an Algerian medicinal plant used in folk medicine to treat different diseases related to hyperglycemic and inflammatory disorders, as well as in food. The present study aimed to assess the total phenolic content, in vitro antioxidant and antimicrobial activity and phytochemical profile of the extracts of C. parviflora. The extraction of phenolic compounds from aerial parts was conducted using solvents of increasing polarity starting from methanol, resulting in crude extract (CE), to chloroform extract (CHE), ethyl acetate extract (EAE) and butanol extract (BUE). The total phenolic, flavonoid and flavonol contents of the extracts were determined using the Folin-Ciocalteu and AlCl3 methods, respectively. The antioxidant activity was measured with seven methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, galvinoxyl free-radical-scavenging test, 2,2'-Azino-Bis(3-Ethylbenzothiazoline-6-Sulfonic Acid) (ABTS) assay, cupric reducing antioxidant capacity (CUPRAC), reducing power, Fe+2-phenanthroline reduction assay and superoxide-scavenging test. The disc-diffusion method aimed at testing the sensitivity of bacterial strains toward our extracts. A qualitative analysis with thin-layer chromatography of the methanolic extract was performed. Moreover, HPLC-DAD-MS was used to establish the phytochemical profile of the BUE. The BUE was found to contain high amounts of total phenolics (175.27 ± 2.79 µg GAE/mg E), flavonoids (59.89 ± 0.91 µg QE/mg E) and flavonols (47.30 ± 0.51 µg RE/mg E). Using TLC, different components such as flavonoids and polyphenols were noted. The highest radical-scavenging ability was recorded for the BUE against DPPH (IC50 = 59.38 ± 0.72 µg/mL), galvinoxyl (IC50 = 36.25 ± 0.42 µg/mL), ABTS (IC50 = 49.52 ± 1.54 µg/mL) and superoxide (IC50 = 13.61 ± 0.38 µg/mL). The BUE had the best reducing power according to the CUPRAC (A0.5 = 71.80 ± 1.22 µg/mL), phenanthroline test (A0.5 = 20.29 ± 1.16 µg/mL) and FRAP (A0.5 = 119.17 ± 0.29 µg/mL). The LC-MS analysis of BUE allowed us to identify eight compounds including six phenolic acids and two flavonoids: quinic acid, five chlorogenic acid derivatives, rutin and quercetin 3-o-glucoside. This preliminary investigation revealed that the extracts of C. parviflora have a good biopharmaceutical activity. The BUE possesses an interesting potential for pharmaceutical/nutraceutical applications.


Assuntos
Anti-Infecciosos , Centaurea , Antioxidantes/química , Cromatografia Líquida , Fenantrolinas , Superóxidos , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Flavonoides/análise , Fenóis/análise , Compostos Fitoquímicos/química
3.
Microb Drug Resist ; 28(3): 274-279, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34860598

RESUMO

This study aimed to determine the incidence and the molecular mechanisms of carbapenem-resistant Enterobacteriaceae in patients from the Sétif University Hospital, Algeria. Nonduplicate clinical bacterial isolates recovered from patients attending the University Hospital of Sétif were collected between April and October 2018. Species identification was performed by MALDI-TOF/MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) method. The susceptibility of the isolates to carbapenems was determined using the disc diffusion method. The carbapenem resistant isolates were screened for the presence of common carbapenemase genes (blaKPC, blaOXA-48, blaVIM, blaIMP, and blaNDM) and extended-spectrum ß-lactamase (blaCTX, blaTEM, and blaSHV) using PCR and sequencing technique. A total of 123 nonrepetitive Enterobacteriaceae isolates were obtained. Klebsiella pneumoniae (n = 52/42.28%), Escherichia coli (n = 24/19.51%), and Enterobacter cloacae (n = 19/15.45%) were the most prevalent species. The Carba-NP test showed that 6 out of 123 isolates carried carbapenemase enzymes. OXA-48 was found in five isolates (four K. pneumoniae and one E. coli) and NDM-5 in one E. cloacae isolate. We reported for the first time in Algeria the presence of NDM-5 carbapenemase enzyme in a clinical E. cloacae isolate.


Assuntos
Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Argélia , Proteínas de Bactérias/genética , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Genes Bacterianos/genética , Hospitais Universitários , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
4.
J Ethnopharmacol ; 208: 105-116, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28663147

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Reichardia picroide is a species mainly used for alimentary purposes, but it is traditionally known to be used as hypoglycemiant, diuretic, depurative, galactagogue and tonic. AIM OF THE STUDY: To date, there are no studies corroborating both its safety and antioxidant activities. The objective of the present study, thus, was to assess the safety profile of Reichardia picroide methanolic extract (RPE) and as well as on its antioxidant and antihemolytic activities. MATERIALS AND METHODS: The acute toxicity of RPE was carried out based on OECD guidelines 425. Signs accompanying toxicity and possible death of animals were monitored for two weeks to ascertain the median lethal dose (LD50) of the RPE. In sub-acute toxicity study, the extract was administered by gavage at the doses of 250, 500 and 1000mg/kg/day for 21 consecutive days. The antioxidant activity of RPE was investigated through various methods both in vitro and in vivo. RESULTS: The admistrated doses did not produce mortality or changes in general behaviors of the tested males and females mice. The LD50 was found to be superior to 5000mg/kg DW. Moreover, daily administration of RPE at doses ranged from 500 to 1000mg/kg could result in alteration of liver and kidney histology. Significant decrease in liver enzymes (ALT and AST), urea and creatinine levels in female plasma was recorded. The RPE was, in vitro, strong in DPPH scavenging and hemolytic inhibition, benificial in lipid peroxidation inhibition and reducing power. In addition, it exhibited, in vivo, a strong effect on GSH level increasing and lipid peroxidation inhibition in liver and kidney. CONCLUSIONS: It can be suggested, based on the results of this study, that the crude extract of Reichardia picroide was non-toxic in acute administration and the use of this extract is safe at doses ≤ 250mg/kg. This study supports the application of Reichardia picroides in alimentary and traditional medicine purposes. Moreover, antioxidant activity results suggested that Reichardia picroide had potent antioxidant activities and could be utilized as new natural antioxidant in food and therapeutics.


Assuntos
Antioxidantes/toxicidade , Asteraceae , Extratos Vegetais/toxicidade , Animais , Eritrócitos/efeitos dos fármacos , Feminino , Glutationa/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Nível de Efeito Adverso não Observado , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
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