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1.
J Pharm Biomed Anal ; 248: 116332, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38964165

RESUMO

Malondialdehyde (MDA) has long been served as a crucial indicator for assessing cellular oxidative stress levels. In this study, we introduce a new approach to determine cellular MDA levels based on a methyl tert-butyl ether (MTBE) extraction, aimed at eliminating interferences from cellular components during thiobarbituric acid (TBA) derivatization of MDA. By leveraging the effective MTBE extraction, we identified that the determination of the MDA-TBA adduct formed from the MTBE extraction layer can effectively eliminate the interferences from cellular proteins and metabolites. This method demonstrated acceptable linearity and precision in cellular samples and showed significant differences in H2O2 treated cellular oxidative stress models. The MTBE extraction-based MDA-TBA approach provides a reliable, cost-effective, and feasible method to determine cellular MDA levels using batch microplate reader approach for the assessment of cellular oxidative stress.


Assuntos
Peróxido de Hidrogênio , Malondialdeído , Éteres Metílicos , Estresse Oxidativo , Malondialdeído/metabolismo , Malondialdeído/análise , Estresse Oxidativo/efeitos dos fármacos , Éteres Metílicos/química , Humanos , Tiobarbitúricos/química
2.
Methods Mol Biol ; 2522: 351-362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36125762

RESUMO

Many research areas, e.g., basic research but also applied fields of biotechnology, biomedicine, and diagnostics often suffer from the unavailability of metabolic compounds. This is mostly due to missing easy and efficient synthesis procedures. We herein describe the biocatalytic/enzymatic production of 2-keto-3-deoxy-D-gluconate, an intermediate of central metabolic pathways in all three domains of life and also of bacterial polysaccharides, lipopolysaccharides, and cell wall components. The method is based on the gluconate dehydratase from the hyperthermophilic crenarchaeon Thermoproteus tenax, which can be easily recombinantly overproduced in Escherichia coli and-due to its intrinsic thermostability-rapidly be purified by two precipitation steps. The enzyme completely converts D-gluconate to solely stereochemically pure KDG, taking benefits from the enol-keto-tautomerism of the primary reaction product. The final product can then easily be separated from the protein by ultrafiltration. The simple one-step procedure, which is suitable at least for the lab-scale/gram-scale production of KDG, replaces lengthy multi-step reactions and is easily scalable. This approach also illustrates the great application potential of Archaea with their unusual metabolic pathways and enzymes for the synthesis of added value products.


Assuntos
Thermoproteus , Escherichia coli/metabolismo , Gluconatos/metabolismo , Hidroliases , Lipopolissacarídeos/metabolismo , Thermoproteus/metabolismo
3.
Saudi J Biol Sci ; 28(11): 6471-6479, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34759756

RESUMO

Foxtail millet (Pennisetum glaucum L.) is a vital crop that is planted as food and fodder crop around the globe. There is only limited information is present for abiotic stresses on the physiological responses to atrazine. A field experiment was conducted to investigate the effects of different atrazine dosages on the growth, fluorescence and physiological parameters i.e., malonaldehyde (MDA) and reactive oxygen species (ROS) (H2O2 and O2) in the leaves to know the extent of atrazine on oxidative damage of foxtail millet. Our experiment consisted of 0, 2.5, 12.5, 22.5 and 32.5 (mg/kg) of labeled atrazine doses on 2 foxtaill millet varieties. High doses of atrazine significantly enhanced ROS and MDA synthesis in the plant leaves. Enzymes activities like ascorbate peroxidase (APX) and peroxidase (POD) activities enhanced, while catalase (CAD) and superoxide dismutase (SOD) activities reduced with increasing atrazine concentrations. Finally atrazine doses at 32.5 mg/kg reduced chlorophyll contents, while chlorophyll (a/b) ratio also enhanced. Biomass, plant height, chlorophyll fluorescence parameters, minimal and maximal fluorescence (Fo, Fm), maximum and actual quantum yield, photochemical quenching coefficient, and electron transport rate are decreased with increasing atrazine doses.

4.
Eur J Pharmacol ; 907: 174257, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129881

RESUMO

The study aimed to assess the possible protective impact of protocatechuic acid (PCA) on high fat diet (HFD)-induced metabolic syndrome (Mets) sequelae in rats. Forty-two male Sprague-Dawley (SD) rats were randomly grouped as follows: CTR group; PCA group; HFD group; HFD-PCA group and HFD-MET group. Rats were fed on standard diet or HFD for 14 weeks. HFD-fed rats exhibited significant decreases in food intake and adiponectin (ADP) level; yet, body weight and anthropometrical parameters were significantly increased. Moreover, insulin sensitivity was impaired as indicated by significant elevation in glucose AUC during oral glucose tolerance test (OGTT), fasting serum glucose, fasting serum insulin and homeostasis model assessment of insulin resistance (HOMA-IR) index. Furthermore, chronic HFD feeding elicited significant increases in serum lipid profile and free fatty acids (FFAs) with concomitant hepatic steatosis. Additionally, serum C-reactive protein (CRP), interleukin 1b (Il-1b) and monocyte chemoattractant protein 1(MCP-1) levels were increased. Also, HFD-fed rats exhibited an increase in MDA level, while superoxide dismutase (SOD) and glutathione (GSH) activities were decreased. Moreover, the insulin-signaling pathway was markedly impaired in soleus muscles as indicated by a decrease in insulin-induced AKT phosphorylation. Histopathologically, adipose tissues showed significant increase in adipocyte size. Also, flow cytometry analysis of adipose tissue confirmed a significant increase in the percentage of number of CD68+ cells. PCA administration succeeded to attenuate HFD-induced obesity, insulin resistance, oxidative stress and inflammation. In conclusion, PCA administration could protect against HFD-induced Mets, possibly via its hypoglycemic, insulin-sensitizing, anti-oxidant and anti-inflammatory effects.


Assuntos
Resistência à Insulina , Animais , Dieta Hiperlipídica , Fígado Gorduroso/metabolismo , Teste de Tolerância a Glucose , Masculino , Obesidade/metabolismo , Ratos
5.
Braz. arch. biol. technol ; 62: e19180365, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055401

RESUMO

Abstract In this study, we aim to determine the shelf life of dried and ready to use-powdered soup samples obtained from different types of fish species such as Rainbow trout (Oncorhynchus mykiss), sea bream (Sparusaurata L.) and sea bass (Dicentrarchuc labrax). For this purpose, the chemical (moisture, protein, fat, carbohydrate, ash, pH, Thiobarbituric acid (TBA), Total volatile basic nitrogen (TVB-N), microbiological (total mesophilic aerobic bacteria, total yeast and mold, total coliform, Staphylococcus spp. and Salmonella spp.) and sensory properties of fish soup samples were determined during 6-month storage period. The pH, TBA and TVB-N values of all samples increased during the storage period, but these values were within the consumption limits. Additionally, the microbiological properties of all fish soup samples were found within the consumption limits during storage. As a result, a product has been obtained with high nutritional value and rich with regard to protein, oil, and minerals by adding the fish meat to soup samples. It has been determined that the product quality and shelf life significantly increased by using the boiled product for the production of soup samples.


Assuntos
Tiobarbitúricos/análise , Sopas , Armazenamento de Alimentos/normas , Peixes , Nitrogênio/análise
6.
Toxicol Rep ; 5: 919-926, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30225197

RESUMO

There is an increasing interest against to fight of diabetes by using hypoglycemic plants in the world. The public thinks that Heracleum persicum (HP) has antidiabetic effect local consumer in Turkey. As far as our literature survey, no studies have been reported so far on antidiabetic effects and toxic risk potential of the HP lyophilized extract supplementation used in this study. The aim of this study, for the first time, was to investigate the therapeutic effects of diabetic complications, antioxidant properties and toxic risk potential of HP against experimentaly streptozotocin (STZ) induced diabetes in rats, which were evaluated by measuring the level of serum biomarker releated diabetes complications changes such glucose, insülin, c-peptide, lipid profile (LP), hepatic and renal damage biomarkers (HRDB), glucosylated hemoglobin (HbA1c), antioxidant defense system constituents (ADSCs), malondialdehyde (MDA) content measured in erythrocyte, brain, kidney and liver tissues, and α-glucosidase activitiy of small intestine. The plant aqueous extract was allowed to freeze-dried under a vacuum at -54 °C to obtain a fine lyophilized extract. The study was performed on STZ-induced diabetic rats (45 mg/kg, body weight (bw), intraperitonally) designed as normal control (NC), diabetic control (DC), diabetes + acarbose (DAC) (20 mg/kg, bw), diabetes + HP (100 mg/kg, bw) (DH1), diabetes + HP (200 mg/kg, bw) (DH2) and diabetes + HP (400 mg/kg, bw) (DH3)] groups. The experimental process lasted 21 days. According to results; the levels of blood glucose (BG), glucosylated hemoglobin (HbA1c) and malondialdehyde (MDA) of DC group increased significantly (p<0.05) compared to NC group, whereas these parameters of the groups treated with oral administrations of HP plant lyophilized extract were observed significant (p<0.05) declines compared to DC. The biochemical analyses showed a considerable decrease in insulin and c-peptide levels and the fluctuated ADSCs in the DC group as compared to control group, whereas the extract supplementations diet restored the diabetic complications parameters towards to the NC. On the other hands, liver damage serum enzymes as serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were incressed significantly (p<0.05) in the plant extract supplementations groups as compared to NC and DC groups. It was concluded that while the extracts of HP have had therapeutic effects on some complications caused by diabetes, but might be caused hepatocyte damage changes as the transport functions and membrane permeability of these cells, thus causing enzymes to leak.

7.
Food Chem ; 205: 264-71, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27006239

RESUMO

Defatting soybean by sophisticated oil extraction method utilising supercritical CO2 resulted in a significant decrease in the residual phospholipids (PLs) compared with soymeal obtained by conventional cold percolation method utilising hexane as the extraction solvent. Interestingly, the levels of residual PLs showed a proportionate relationship with thiobarbituric acid (TBA) number, an indicator of lipid peroxidation responsible for off-flavour generation. Furthermore, two oleosins (18 and 24 kDa) were isolated from the oil bodies extracted from soybean seeds and positively characterised for phospholipase A2 (PLA2) activity, suggesting their plausible involvement in off-flavour generation in soymeal. The treatment of soybean seeds, before oil extraction, with different concentrations of biotic elicitors such as chitosan and jasmonic acid also significantly reduced the levels of residual PLs as well as the TBA number. The biotic elicitor treatment could thus prove to be an important strategy for the reduction of off-flavour in protein-rich soymeal.


Assuntos
Glycine max/química , Óleos de Plantas/química , Proteínas de Plantas/química , Dióxido de Carbono
8.
J Ethnopharmacol ; 176: 243-51, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26505295

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Acorn obtained from the Quercus brantii Lindl. (QB) tree has been used in Turkish folk medicine. Some studies have reported as an antioxidant, antimicrobial, anti-inflammatory, gastroprotective, antitumoural of QB properties previously. however, its effect on the management of type diabetic 2 and oxidative stress complications is still unexplored. The aims of our study were the evaluation of the protective effect and antioxidant role of acorn lyophilized seed plant extract against STZ-induced diabetic complications as oxidative stress, hepatotoxicity and nephropathy, lipidemia and serum biomarkers of diabetes (SBD). MATERIALS AND METHODS: In-vivo studies were performed on STZ-induced diabetic rats Experiment was designed as I [Normal Control (NC)], II [Diabetes mellitus (DM)], III [DM+Acarbose (20mg/kg b.w) (DM+AC-20)], IV [DM+QB (100mg/kg b.w) (DM+QB-100)], V [DM+QB (250 mg/kg b.w) (DM+QB-250)] and VI [DM+QB (500 mg/kg b.w) (DM+QB-500)] groups. RESULTS: This study showed that the biochemical analysis showed a considerable increase in the HRDB, DB, LP, MDA and fluctuated ADSC in the II group as compared to that of control group whereas, AC and the plant lyophilized seed plant extract supplementations diet restored the STZ-induced diabetic complications towards the control. α-glycosidase activity in DM group showed statistically significant increase with respect to control group in small intestine. Moreover, in accordance with the effects of seed extract; in diabetic rat groups to whom acorn seed extract and acarbose were given, the levels of almost all the concerned parameters were reached to the ones measured at control group. As a result, it was concluded that acorn seed extract had certain healing effects on many complications caused by diabetes.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Quercus , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Glicemia/análise , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Diabetes Mellitus Experimental/sangue , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Liofilização , Glutationa Transferase/metabolismo , Glicosídeo Hidrolases/metabolismo , Hiperglicemia/sangue , Hipoglicemiantes/química , Hipoglicemiantes/toxicidade , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Nozes , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Ratos Wistar
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