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1.
Artículo en Inglés | MEDLINE | ID: mdl-32419789

RESUMEN

Growing worldwide, the genus Ephedra (family Ephedraceae) had a medicinal, ecological, and economic value. The extraordinary morphological diversity suggests that Ephedra was survivor of an ancient group, and its antiquity is also supported by fossil data. It has recently been suggested that Ephedra appeared 8-32 million years ago, and a few megafossils document its presence in the Early Cretaceous. Recently, the high analytical power provided by the new mass spectrometry (MS) instruments is making the characterization of Ephedra metabolites more feasible, such as ephedrine series. In this regard, the chemical compounds isolated from crude extracts, fractions, and few isolated compounds of Ephedra species were characterized by MS-based techniques (LC-MS, LC-ESI-MS, HPLC-PDA-ESI/MS, LC-DAD-ESI/MSn, LC/Orbitrap MS, etc.). Moreover, we carry out an exhaustive review of the scientific literature on biomedicine and pharmacotherapy (anticancer, antiproliferative, anti-inflammatory, antidiabetic, antihyperlipidemic, antiarthritic, and anti-influenza activities; proapoptotic and cytotoxic potential; and so on). Equally, antimicrobial and antioxidant activities were discussed. This review is focused on all these topics, along with current studies published in the last 5 years (2015-2019) providing in-depth information for readers.

2.
Environ Sci Pollut Res Int ; 27(13): 15842-15855, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32095964

RESUMEN

The efficiency of the proteolytic strain Anoxybacillus kamchatkensis M1V in the fermentation of speckled shrimp by-product was investigated for the recovery of a deproteinized bioactive hydrolysate. The biological activities of the resulting hydrolysate were also examined by applying several antioxidant and enzyme inhibitory assays. The strain M1V was found to produce high level of protease activity (2000 U/mL) when grown in media containing only shrimp powder at 25 g/L. The crude protease displayed a significant deproteinization capabiliy, with the best efficiency (48%) being recorded for an enzyme to substrate (E/S) ratio of 30 U/mg. Following the deproteinization, chitin was recovered and the authenticity was confirmed by Fourier-transform infrared spectroscopy (FTIR) analysis. On the other hand, the obtained hydrolysate showed a significant enzymatic inhibitory potential against acetylcholinesterase, tyrosinase, amylase, and angiotensin I convertase, and a strong antioxidant activity. Graphical Abstract.


Asunto(s)
Penaeidae , Animales , Anoxybacillus , Quitina , Endopeptidasas , Fermentación
3.
Int J Biol Macromol ; 148: 1156-1168, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31917214

RESUMEN

A novel polysaccharide extracted from green algae Chaetomorpha linum (PS) was characterized, using infrared spectroscopy, HPLC-FID, gel filtration high-pressure chromatography, thin layer chromatography and spectrum visible UV. Natural antioxidant potential of PS was evaluated based on DPPH free radical, ferrous iron-chelating, ß carotene bleaching inhibition activities and DNA nicking assay. Functional properties were estimated based on Water Holding Capacity (WHC), Oil Holding Capacity (OHC), emulsifying activity and foaming ability. Overall, data showed attractive chemical, functional and biological properties with an antioxidant capacity of PS in beef sausages during storage for 12 days. Indeed, as compared to standard formulation (with addition of vitamin C), samples formulated with PS presented lower values in terms of lipid oxidation (TBARS, MetMb), while preserving color properties compared with untreated samples. Furthermore, lower changes in pH, moisture, and the highest values of heme iron were obtained. Successful inhibition of microbial proliferation was proved. Endowed with high antioxidant and antimicrobial activities, PS could thus be used as a natural conservative in functional foods.


Asunto(s)
Productos Biológicos/química , Productos Biológicos/farmacología , Aditivos Alimentarios , Polisacáridos/química , Polisacáridos/farmacología , Carne Roja , Algas Marinas/química , Animales , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Productos Biológicos/aislamiento & purificación , Bovinos , Cromatografía Líquida de Alta Presión , Hemo/química , Metales/química , Polisacáridos/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier
4.
Artículo en Inglés | MEDLINE | ID: mdl-31737081

RESUMEN

Pomegranate (Punica granatum L.) peel is a potential source of polyphenols known for their activity against foodborne pathogen bacteria. In this study, the effects of pomegranate peel extraction time (10-60 min), agitation speed (120-180 rpm), and solvent/solid ratio (10-30) on phytochemical content and antibacterial activity were determined. Response surface methodology (RSM) and artificial neural network (ANN) methods were used, respectively, for multiresponse optimization and predictive modelling. Compared with the original conditions, the total phenolic content (TPC), the total flavonoid content (TFC), and the total anthocyanin content (TAC) increased by 56.22, 63.47, and 64.6%, respectively. Defined by minimal inhibitory concentration (MIC), the maximum of antibacterial activity was higher than that from preoptimized conditions. With an extraction time of 11 min, an agitation speed 125 rpm, and a solvent/solid ratio of 12, anti-S. aureus activity remarkably decreased from 1.56 to 0.171 mg/mL. Model comparisons through the coefficient of determination (R 2) and mean square error (MSE) showed that ANN models were better than the RSM model in predicting the photochemical content and antibacterial activity. To explore the mode of action of the pomegranate peel extract (PPE) at optimal conditions against S. aureus and S. enterica, Chapman and Xylose Lysine Deoxycholate broth media were artificially contaminated at 104 CFU/mL. By using statistical approach, linear (ANOVA), and general (ANCOVA) models, PPE was demonstrated to control the two dominant foodborne pathogens by suppressing bacterial growth.

5.
Meat Sci ; 158: 107914, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31437671

RESUMEN

The growing demand for natural food preservatives has promoted investigations on their application for preserving perishable foods. Consequently, the meat market is demanding natural antioxidants, free of synthetic additives and able to diminish the oxidation processes in high-fat meat and meat products. In this context, the present review discuss the development of healthier and shelf stable meat products by the successful use of pomegranate peel extracts containing phenolics as natural preservative agent in meat and meat products. This paper carries out an exhaustive review of the scientific literature on the main active phenolic compounds of pomegranate peel identified and quantified by advances in the separation sciences and spectrometry, and its biological activities evaluation. Moreover, the impact of pomegranate peel use on the quality and oxidative stability of meat products is also evaluated. As natural preservative, pomegranate peel phenolics could improve stored meat products quality, namely instrumental color retaining, limitaion of microflora growth, retardation of lipid and protein oxidation.


Asunto(s)
Frutas/química , Productos de la Carne/análisis , Granada (Fruta) , Animales , Antioxidantes/análisis , Conservantes de Alimentos/análisis , Fenoles/análisis , Extractos Vegetales/química
6.
Environ Toxicol ; 34(11): 1165-1176, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31328355

RESUMEN

The present study aimed to evaluate the potential protective and antioxidant effect of polysaccharides (PS) extracted from Ulva lactuca against thiacloprid (THC) induced nephrotoxicity and hepatotoxicity. The antioxidant capacity of PS was tested in vitro using ABTS radical scavenging activity and plasmid DNA cleavage assays andin vivo on adult male rats treated for 30 days. Animals were allocated into four groups: control; THC (22.5 mg/kg); THC (22.5 mg/kg) + PS1 (100 mg/kg diet); and THC (22.5 mg/kg) + PS2 (200 mg/kg diet). The structural features of PS were determined by Fourier transformed infrared (FT-IR), UV absorption peak detection, high performance liquid chromatography (HPLC) and gel permeation chromatography, and also functional properties were investigated. Overall, results indicated that THC increased significantly malondialdehyde, advanced oxidation protein products, glutathione levels, which is correlated with severe histological and plasmatic biochemical injuries in both liver and kidney tissues. However, cotreatment PS induced a significant protective and healing affects against the nephrotoxicity and hepatotoxcity induced by THC.


Asunto(s)
Contaminantes Ambientales/toxicidad , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Polisacáridos/farmacología , Tiazinas/toxicidad , Ulva/metabolismo , Animales , Antioxidantes/química , Antioxidantes/metabolismo , Creatinina/sangre , Glutatión/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Malondialdehído/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polisacáridos/química , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo
7.
Biomed Res Int ; 2019: 4094890, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31119168

RESUMEN

Safety aspects and probiotic properties of Enterococcus faecium FL31 strain producing an enterocin, named BacFL31 were previously demonstrated. Taking into account its originality, the enterocin BacFL31 was added alone at 200 AU/g or in combination with the aqueous peel onion (Allium cepa) extract (APOE) at 1.56 ± 0.3 mg/mL to ground beef meat. Its biopreservative effect was evaluated by microbiological, physicochemical and sensory analyses during 14 days at 4°C. The APOE was characterized for its phytochemical content: total phenolic (TPC), flavonoids (TFC) and tannins contents (TAC), its antioxidant capacity using the in vitro 1,1-diphenyl-2-picrylhydrazyl (DPPH) and its antilisterial activity. APOE had a high TPC, TFC and TAC respectively with 140 ± 2.05 (mg GAE/g), 35 ± 0.5 (mg QE/g) and 20.6 ± 1.4 (mg CE/g). Equally, APOE showed a potential radical scavenging activity compared to the butylated hydroxytoluene (BHT), with an anti-radical power (ARP) of 46 ± 1.5. During 14 days of storage at 4°C, the combination between APOE and BacFL31 limited the microbial deterioration (P < 0.05), led to a decrease in thiobarbituric acid reactive substances (TBARS) values and slowed down the metmyoglobin (MetMb) and carbonyl group accumulation and delayed the disappearance of sulfphydryl proteins (P < 0.05). The combination was also efficient (P < 0.05) against microflora proliferation, decreased primary and secondary lipid oxidation (P < 0.05), reduced protein oxidation and enhanced significantly (P < 0.05) the sensory attributes. Thus, the enterocin BacFL31 use from a safe Enterococcus faecium combined with APOE as a potential natural preservative to biocontrol ground beef was promising as it was effective at low concentration. The data lay bases for new tests to be carried out in other food matrices.


Asunto(s)
Microbiología de Alimentos , Conservación de Alimentos , Cebollas/química , Animales , Productos Biológicos/química , Hidrocarburos Aromáticos con Puentes/farmacología , Bovinos , Enterococcus faecium/química , Almacenamiento de Alimentos , Humanos , Carne/microbiología , Carne Roja/microbiología
8.
Biomed Res Int ; 2018: 5308464, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30515405

RESUMEN

In previous work we have isolated and identified a new strain called Enterococcus faecium FL31. The active compound secreted by this strain, "BacFL31", has been purified and characterized. In the present study, safety aspect, assessed by microbiological and molecular tests, demonstrated that Enterococcus faecium FL31 was susceptible to relevant antibiotics, free of hemolytic, gelatinase, DNase, and lipase activities. In addition, it did not harbor virulence and antibiotic resistance genes. Combined SYTOX Green dye and UV-absorbing experiments, along with released extracellular potassium and transmembrane electrical potential measurements, showed that pure BacFL31 at a concentration of 1×MIC (50 µg/mL) could damage cytoplasmic membrane of the pathogen Listeria monocytogenes ATCC19117. The same concentration causes the leakage of its intracellular constituents and leads to the destruction of this pathogenic microorganism. In summary, this work reflected characteristics of Enterococcus faecium FL31 strain and its bacteriocin in terms of functional and safety perspectives.


Asunto(s)
Antibacterianos/farmacología , Bacteriocinas/farmacología , Enterococcus faecium/química , Listeria monocytogenes/efectos de los fármacos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Bacteriocinas/química , Bacteriocinas/aislamiento & purificación , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Hidroxilación , Listeria monocytogenes/patogenicidad , Listeriosis/tratamiento farmacológico , Listeriosis/microbiología , Potenciales de la Membrana/efectos de los fármacos , Compuestos Orgánicos/química , Potasio/química
9.
Microb Pathog ; 119: 19-27, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29626659

RESUMEN

A new aerobic bacterium TN71 was isolated from Tunisian Saharan soil and has been selected for its antimicrobial activity against phytopathogenic bacteria. Based on cellular morphology, physiological characterization and phylogenetic analysis, this isolate has been assigned as Streptomyces sp. TN71 strain. In an attempt to increase its anti-Agrobacterium tumefaciens activity, GYM + S (glucose, yeast extract, malt extract and starch) medium was selected out of five different production media and the medium composition was optimized. Plackett-Burman design (PBD) was used to select starch, malt extract and glucose as parameters having significant effects on antibacterial activity and a Box-Behnken design was applied for further optimization. The analysis revealed that the optimum concentrations for anti-A. tumefaciens activity of the tested variables were 19.49 g/L for starch, 5.06 g/L for malt extract and 2.07 g/L for glucose. Several Artificial Neural Networks (ANN): the Multilayer perceptron (MLP) and the Radial basis function (RBF) were also constructed to predict anti-A. tumefaciens activity. The comparison between experimental with predicted outputs from ANN and Response Surface Methodology (RSM) were studied. ANN model presents an improvement of 12.36% in terms of determination coefficients of anti A. tumefaciens activity. To our knowledge, this is the first work reporting the statistical versus artificial intelligence based modeling for optimization of bioactive molecules against phytopathogens.


Asunto(s)
Agrobacterium tumefaciens/efectos de los fármacos , Antibacterianos/metabolismo , Antibacterianos/farmacología , Streptomyces/metabolismo , Antibacterianos/aislamiento & purificación , Medios de Cultivo/química , ADN Bacteriano , Fermentación , Pruebas de Sensibilidad Microbiana , Redes Neurales de la Computación , Filogenia , ARN Ribosómico 16S/genética , Metabolismo Secundario , Suelo , Microbiología del Suelo , Especificidad de la Especie , Streptomyces/clasificación , Streptomyces/genética , Streptomyces/aislamiento & purificación , Túnez
10.
Biocontrol Sci ; 22(2): 67-77, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28659558

RESUMEN

 The effect of the semi purified bacteriocin BacFL31 at 200 and 400 AU/g on the shelf life of refrigerated raw ground turkey meat was investigated. The microbiological, physicochemical, and sensory properties of the meat samples were examined during refrigerated storage. The findings indicated that BacFL31 treatments were effective (p<0.05) against the proliferation of various spoilage microorganisms and suppressed the growth of Listeria monocytogenes and Salmonella Typhimurium. The pH, % Met-MB, and TBA-RS values of the treated samples were lower (p<0.05) than those of their control samples. The addition of BacFL31 extended the shelf life and enhanced the sensory attributes of the turkey meat samples during refrigerated storage. These results suggest that BacFL31 could be considered a promising candidate for future application as an additive to preserve the raw turkey meat during storage at 4℃.


Asunto(s)
Bacteriocinas/química , Microbiología de Alimentos , Conservación de Alimentos/métodos , Carne/normas , Humanos , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Carne/microbiología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/crecimiento & desarrollo
11.
J Basic Microbiol ; 57(5): 393-401, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28217886

RESUMEN

An actinomycete strain designated TN258, was isolated from Tunisian Sahara soil and selected for its antagonistic activity, especially against Pythium ultimum (P. ultimum) causing potato tubers leak. Based on the results of cultural characteristic of TN258 strain, the 16S rRNA gene nucleotide sequence (1433 bp, accession n° HE600071) and the phylogenetic analysis, we propose the assignment of our new isolate bacterium as Streptomyces TN258 strain. After culture optimization, the inhibitory effect of TN258 free cell supernatant against P. ultimum was evaluated. As result, by application of 50% (v/v) from 25 mg ml-1 of concentration, mycelial growth was totally inhibited with hyphal destruction. At the same concentration, the oospores were distorted and the germination was completely stopped. In potato tubers, Streptomyces TN258 filtrated supernatant, applied 24 h before inoculation by P. ultimum (preventive treatment group) was able to significantly decrease pathogen penetration by 62% and to reduce the percentage of weight loss by 59.43%, in comparison with non-treated group.


Asunto(s)
Enfermedades de las Plantas/terapia , Pythium/patogenicidad , Microbiología del Suelo , Solanum tuberosum/microbiología , Solanum tuberosum/parasitología , Streptomyces/aislamiento & purificación , Streptomyces/fisiología , ADN Bacteriano , Genes Bacterianos , Germinación , Hifa , Control Biológico de Vectores/métodos , Filogenia , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/parasitología , Plantas/microbiología , Pythium/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Streptomyces/genética
12.
Meat Sci ; 117: 196-204, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26995774

RESUMEN

The major compounds in Mentha piperita essential oil (EOMP) were menthol (33.59%) and iso-menthone (33%). The biopreservative effect of EOMP used alone at 0.25 or 0.5% and in combination with the semi-purified bacteriocin BacTN635 at 500 or 1000AU/g, on minced beef meat was evaluated by microbiological, physicochemical and sensory analyses during storage at 4°C for 21days. EOMP used alone limited the microbial deterioration of minced meat (P<0.05). Furthermore, the combination between EOMP and BacTN635 led to a decrease in TBARS values and slowed down the accumulation of MetMb. This combination was more efficient (P<0.05) against microflora proliferation and enhanced the sensory acceptability extending thus the shelf life of meat beef by approximately 7days. On the basis of these results, physicochemical and sensorial parameters could be used for constructing regression models to predict overall acceptability. Overall, the strongest preservative effect was achieved by using the combination of EOMP at 0.5% with BacTN535 at 1000AU/g.


Asunto(s)
Bacteriocinas , Conservantes de Alimentos/química , Mentha piperita/química , Aceites Volátiles/química , Aceites de Plantas/química , Carne Roja/análisis , Adulto , Femenino , Conservación de Alimentos , Almacenamiento de Alimentos , Humanos , Masculino , Persona de Mediana Edad , Sensación , Gusto , Adulto Joven
13.
Anaerobe ; 27: 1-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24583094

RESUMEN

A new bacterium called FL31, which was selected for its antimicrobial activity against the pathogenic bacterium Listeria monocytogenes, was identified as Enterococcus faecium and noted to produce an antibacterial proteinaceous substance (BacFL31). The active peptide from the cell-free supernatant of E. faecium FL31 was purified in four steps and the results revealed a single band with an estimated molecular mass of approximately 3.5 kDa. The N-terminal amino acid sequence of the purified BacFL31 "GLEESXGHXGQXGPXGPXGAXGP" (X = hydroxyproline) showed the presence of six hydroxyproline residues. It displayed a bactericidal mode of action against L. monocytogenes. Its application at 400 AU/g was also noted to constitute an effective approach for preventing the contamination and growth of the pathogenic bacterium L. monocytogenes during the storage of minced beef meat at 4 °C.


Asunto(s)
Bacteriocinas/química , Bacteriocinas/farmacología , Enterococcus faecium/metabolismo , Hidroxiprolina/análisis , Listeria monocytogenes/efectos de los fármacos , Péptidos/química , Péptidos/farmacología , Secuencia de Aminoácidos , Bacteriocinas/aislamiento & purificación , Bacteriocinas/metabolismo , Conservación de Alimentos/métodos , Listeria monocytogenes/crecimiento & desarrollo , Viabilidad Microbiana/efectos de los fármacos , Peso Molecular , Péptidos/aislamiento & purificación , Péptidos/metabolismo
14.
Food Chem ; 152: 566-72, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24444976

RESUMEN

During a screening programme for bacteriocin producers, a new lactic acid bacterium called J1, isolated from chicken gizzard, was noted to produce a bacteriocin (BacJ1) that inhibited Gram-positive and Gram-negative food-borne pathogens, especially Salmonella typhimurium, and it was, therefore, selected for identification and further study. The results, from 16S rRNA gene nucleotide sequencing (1583 pb accession no HE861352) and phylogenetic analysis, suggested that the new isolate be assigned as Weissella paramesenteroides J1. BacJ1 was purified from the culture supernatant of the J1 strain using heat treatment (15 min at 90 °C), 80% ammonium sulfate precipitation, and gel filtration (Sephadex G25). MALDI-TOF analyses revealed that BacJ1 had an exact molecular mass of 1881.036 Da. The analysis of the N-terminal sequence (GPAGPFGKLY) of this active peptide revealed no significant similarity to currently available antimicrobial peptides. The addition of pre-purified BacJ1, at a final concentration of 400 AU per gramme, may open new promising opportunities for the prevention of contamination from and growth of pathogenic bacteria, particularly S. typhimurium, during turkey escalope storage at 4 °C.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Bacteriocinas/química , Bacteriocinas/farmacología , Carne/microbiología , Salmonella typhimurium/efectos de los fármacos , Weissella/metabolismo , Animales , Antibacterianos/metabolismo , Bacteriocinas/genética , Bacteriocinas/metabolismo , Pollos , Contaminación de Alimentos/prevención & control , Almacenamiento de Alimentos , Molleja de las Aves/microbiología , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Datos de Secuencia Molecular , Peso Molecular , Salmonella typhimurium/crecimiento & desarrollo , Pavos , Weissella/química , Weissella/genética , Weissella/aislamiento & purificación
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