1,153 research outputs found

    Antioxidant potential of individual or combined dietary supplements

    Get PDF
    An antioxidant may be defined as a substance that when present at low concentrations, compared with those of the oxidizable substrate, significantly delays or inhibits its oxidation [1]. Nowadays there are several commercial dietary supplements which claim for antioxidant activity. In this work, the antioxidant activity (AA) of 17 dietary supplements (Table 1) available in different formulations (pills, capsules or bags), was evaluated by in vitro assays: scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, reducing power (RP) and inhibition of lipid peroxidation by preventing the formation of thiobarbituric acid reactive substances (TBARS). Furthermore, different combinations (8+10+17, 8+10, 8+17 and 10+17) of some samples were also tested in order to obtain potential synergistic effects. Linear discriminant analysis (LDA) was used to categorize the condensed formulations (pills and capsules), the infusion bags and the combined samples, according with their antioxidant activity. The Advanced Antioxidant Formula (AAF; sample 8) proved to have the highest antioxidant activity in all the assayed methods, either singly taken or included in mixtures. Furthermore, the mixtures containing this supplement revealed synergistic effects in 92% of the cases. The intake of antioxidant mixtures might provide some additional benefits

    Dietary antioxidant supplements: benefits of their combined use

    Get PDF
    Several dietary supplements claim medicinal benefits due to their composition in hydrophilic and lipophilic molecules, natural extracts or synthetic compounds with antioxidant properties. In the present work, the antioxidant activity of selected supplements taken in pills, capsules or infusions were studied either individually or combined. Linear discriminant analysis (LDA) was used to categorize the condensed formulations (pills and capsules), infusion bags and combined samples according with their antioxidant activity measured by radical scavenging activity, reducing power and lipid peroxidation inhibition using brain homogenates as models. AAF proved to have the highest antioxidant activity in all the assayed methods, either singly taken or included in mixtures. Furthermore, the mixtures containing this supplement revealed synergistic effects in 92% of the cases. The intake of antioxidant mixtures might provide some additional benefits

    On The Distribution Of Siphonops Paulensis Boettger, 1892 (gymnophiona: Siphonopidae): Four New Brazilian State Records

    Get PDF
    Siphonops paulensis Boettger, 1892 is a Neotropical siphonopid caecilian widely distributed in South America. Herein, we fill knowledge gaps in the distribution of S. paulensis mostly in northeastern Brazil, including four new state records. © 2016 Check List and Authors.12

    Effect of modified atmosphere on polyphenols during storage of pasteurised strawberry purees

    Get PDF
    The minimum loss of processed fruit nutritional quality must been guaranteed during storage and the atmosphere can be a limiting step. Strawberry pur ees flushed with gas mixtures: 10 kPa O2 þ 90 kPa N2, 100 kPa N2 and air (78 kPa N2 þ 21 kPa O2 þ 0.03 kPa CO2) were stored for 90 days at 4 and 23 C and revealed no effect in total antioxidant activity and in total phenolic content. The compounds (þ)-catechin, ( )-epicatechin and quercetin-3-rutinoside were not affected by the atmospheres for both temperatures and ellagic acid was the exception within strawberry phytochemicals, where its concentration was higher for samples stored in air. Total anthocyanin content was better preserved when strawberry pur ee was stored in 100 kPa N2 at 4 and 23 C, at which temperatures their levels decreased 24 and 77%, respectively. At 4 C cyanidin-3- glucoside presented no significant differences between atmospheres. Pelargonidin-3-glucoside and pelargonidin-3-rutinoside decreased both 27% for 100 kPa N2 and 45% for 10 kPa O2 and air. All the individual anthocyanins were not affected by the atmospheres when stored at 23 ºC.info:eu-repo/semantics/publishedVersio

    Role of oxidative stress on the etiology and pathophysiology of Amyotrophic Lateral Sclerosis (ALS) and its relation with the enteric nervous system

    Get PDF
    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motor neurons in the spinal cord, cerebral cortex, and medulla oblongata. Most patients present a clinical phenotype of classic ALS—with predominant atrophy, muscle weakness, and fasciculations—and survival of 3 to 5 years following diagnosis. In the present review, we performed a literature search to provide an update on the etiology and pathophysiological mechanisms involved in ALS. There are two types of ALS: the familial form with genetic involvement, and the sporadic form with a multifactorial origin. ALS pathophysiology is characterized by involvement of multiple processes, including oxidative stress, glutamate excitotoxicity, and neuroinflammation. Moreover, it is proposed that conditioning risk factors affect ALS development, such as susceptibility to neurodegeneration in motor neurons, the intensity of performed physical activity, and intestinal dysbiosis with involvement of the enteric nervous system, which supports the existing theories of disease generation. To improve patients’ prognosis and survival, it is necessary to further deepen our understanding of the etiopathogenesis of ALS

    Effect of thyroparathyroidectomy on urinary acidification in diabetic rats

    Get PDF
    In previous studies we have shown stimulation of renal acid excretion in the proximal tubules of rats with diabetes of short duration, with no important alterations in glomerular hemodynamics; on the other hand, in thyroparathyroidectomized rats (TPTX model), a significant decrease in renal acid excretion, glomerular filtration rate (GFR) and renal plasma flow (RPF) was detected. Since important changes in the parathyroid hormone-vitamin D-Ca axis are observed in the diabetic state, the present study was undertaken to investigate the renal repercussions of thyroparathyroidectomy in rats previously made diabetic by streptozotocin (45 mg/kg). Four to 6 days after the induction of diabetes (DM), a group of rats were thyroparathyroidectomized (DM + TPTX). Renal functional parameters were evaluated by measuring the inulin and sodium para-aminohippurate clearance on the tenth day. The decrease in the GFR and RPF observed in TPTX was not reversed by diabetes since the same alterations were observed in DM + TPTX. Net acid (NA) excretion was unchanged in DM (6.19 ± 0.54), decreased in TPTX (3.76 ± 0.25) and returned to normal levels in DM + TPTX (5.54 ± 0.72) when compared to the control group (6.34 ± 0.14 µmol min-1 kg-1). The results suggest that PTH plays an important vasodilator role regarding glomerular hemodynamics, since in its absence the impairment in GFR and RPF was not reversed by the diabetic state. However, with respect to acid excretion, the presence of diabetes was able to overcome the negative stimulus represented by TPTX.Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

    Avaliação do curso de Engenharia de Ordenamento dos Recursos Naturais

    Get PDF
    O relatório resulta do trabalho de avaliação ao curso de Engenharia de Ordenamento dos Recursos Naturais levado a cabo pela equipa de Auto-Avaliação da Escola Superior Agrária. Esta equipa, designada pelo Conselho Científico com a finalidade de proceder a todas as solicitações de avaliação tanto dos cursos como da instituição, é basicamente composta por um coordenador e um elemento de cada unidade departamental. Decorrente do tipo de curso que se está a avaliar juntam-se à equipa os respectivos coordenadores do curso e um relator. Além deste elementos participaram também neste trabalho um representante dos alunos (designado pela associação de estudantes) e dois funcionários representantes do pessoal administrativo e do pessoal não docente. Em termos metodológicos optou-se pelo seguimento do guião proposto pelo CNAVES, tendo-se recolhido informação de diversos modos: pesquisa documental e bases de dados nos serviços administrativos, inquéritos auto administrados a alunos, docentes e funcionários, inquérito postal aos diplomados e entrevistas directas às entidades empregadoras. Uma vez recolhida e tratada a informação procedeu-se à sua análise crítica tendo como referência os trabalhos de avaliação que até então decorreram relativamente à Escola e ao curso de Ordenamento dos Recursos Naturais
    corecore