Paula R. Augusti

Effect of Vernonia cognata on oxidative damage induced by ethanol in rats

Free radicals production and oxidative stress play a central role in injuries caused by ethanol (EtOH) on gastric mucosal. Thus, strategies to counteract EtOH toxicity are highly desirable. This study was aimed at evaluating whether Vernonia cognata extract would reduce EtOH effects in rats. Rats received Vernonia cognata extract (0, 1 and 2 g/kg bw, by gavage) 1 hour after EtOH had been administered (0 or 70%, 0.5 mL/100 g bw, by gavage) and were killed 1 hour after Vernonia cognata extract administration. The stomach was removed for macroscopic and histopathological evaluation, as well as, oxidative stress markers such as lipoperoxidation (LPO) and non-protein thiol groups (NPSH) levels and catalase (CAT) activity. EtOH acute exposure increased LPO and decreased NPSH levels and CAT activity along with macroscopic and microscopic lesions in gastric tissue, confirming the involvement of oxidative stress in EtOH toxicity. Vernonia cognata extract attenuated oxidative and histopathological features induced by EtOH at all evaluated doses. Moreover, both studied doses of Vernonia cognata extract caused an increase in NPSH levels per se. However, only the dose of 2 g/kg reverted all macroscopic changes caused by EtOH toxicity. The protective effect of the extract could be attributed to antioxidant molecules present in the extract, such as flavonoids and phenolic acids, which were quantified by high performance liquid chromatography (HPLC). Thus, an antioxidant effect of the extract leads to a protection on gastric tissue. Our results indicate that Vernonia cognata hydroethanolic extract could have a beneficial role against EtOH toxicity by preventing oxidative stress and gastric tissue injury.

Cultivar, harvest year, and storage conditions affecting nutritional quality of common beans (Phaseolus vulgaris L.

Compararam-se as caracteristicas fisico-quimicas de dezesseis cultivares de feijao-comum cru ao longo de duas safras consecutivas, assim como se avaliou o efeito das condicoes de armazenagem nos teores de amido e fibra alimentar em graos cozidos. A analise de agrupamento possibilitou a identificacao de grupos de cultivares com caracteristicas nutricionais distintas. Estas cultivares foram categorizadas em quatro grupos de acordo com o conteudo de macronutrientes (proteina bruta-PROT, fibra alimentar total-TDF, fibra alimentar insoluvel-IDF, fibra alimentar soluvel-SDF, amido disponivel-DS e amido resistente-RS) ou de micronutrientes (Fe, Zn, Mn, Cu, Ca, Mg, e P). Guateian 6662 e Rio Tibagi mostraram-se as cultivares mais adequadas para prevenir deficiencias nutricionais, devido aos altos teores de PROT, DS, Fe e Zn. Os altos teores de fibra alimentar total e RS das cultivares Irai, Minuano e TPS Bonito, e especialmente os altos teores de fibra soluvel das cultivares Guateian 6662 e Rio Tibagi sugerem que estas poderiam auxiliar no controle dos lipidios e glicose sericos. Os graos cozidos apresentaram reducao no DS e aumento de RS apos armazenagem (4 °C ou -20 °C), mas estas alteracoes foram mais pronunciadas em feijoes que tinham baixos teores de RS antes do cozimento do que naqueles com altos teores. Os teores de TDF, IDF, e SDF nao alteraram apos a armazenagem.

Lead content of dietary calcium supplements available in Brazil

The lead and calcium content of calcium supplements available in Brazil were determined by graphite furnace and flame atomic absorption spectrometry, respectively. Samples were microwave-digested in concentrated HNO3. Citric acid was used as a chemical modifier in the lead analysis. Supplements were classified into six categories: oyster industrialized (OI, n = 4), oyster prepared in pharmacy (OP, n = 3), refined industrialized (RI, n = 6), refined prepared in pharmacy (RP, n = 3), bone meal (B, n = 3), and dolomite (D, n = 4). Lead levels (µg g−1 of measured calcium) were higher in D products (2.33), followed by OI, RP, OP, and RI products (1.46, 1.32, 1.29, 0.75), while B products had levels lower than the limit of quantification (0.02 µg g−1 unit weight). Daily lead intake of eight supplements exceeded the limit of California, USA (1.5 µg g−1 calcium), but none exceeded the federal limit of USA (7.5 µg g−1 calcium) or the provisional tolerable lead intake by FAO/WHO (25 µg kg−1 per week).

Efeito do gelo clorado sobre parâmetros químicos e microbiológicos da carne de carpa capim (Ctenopharyngodon idella)

The rapid spoilage of fishes causes economical losses in the processing and marketing of these products. In the present study, the efficiency of chlorinated ice to increase grass carp (Ctenopharyngodon idella) shelf life was evaluated. Mesophilic and psychrotrophic bacteria count, total volatile basic nitrogen (TVBN) and pH were evaluated in the flesh of grass carp stored refrigerated (3±1oC) for 20 days, covered with chlorinated (5ppm) or non-chlorinated ice. Chlorine significantly reduced (p<0,05) mesophilic and psychrotrophic bacteria count in the flesh, as well as pH and the initial values of TVBN. TVBN values were low and did not exhibit great changes over the storage time. Results showed that grass carp shelf life could be extended around 3 days by using chlorinated ice. Besides, pH and TVBN values were considered unsuitable to assess grass carp spoilage.

Dimethyl sulfoxide and ebselen prevent convulsions induced by 5-aminolevulinic acid.

We investigated whether intrastriatal (i.s.) administration of 5-aminolevulinic acid (ALA) induces oxidative damage and whether behavioral alterations induced by i.s. administration of ALA could be affected by antioxidants. Unilateral injection of ALA (6 μmol/striatum) increased (∼30%) thiobarbituric acid-reactive substances (TBARS), but did not affect striatal content of total thiol groups. ALA-induced body asymmetry was not prevented by pretreatment with ascorbic acid (100 mg/kg, s.c.), dimethyl sulfoxide (DMSO, 0.5 μl/striatum, i.s.) or ebselen (10 nmol/striatum, i.s.). ALA-induced convulsions were not prevented by ascorbic acid, but were partially prevented by DMSO and completely prevented by ebselen. Ebselen completely prevented the increase of striatal TBARS induced by ALA. Results obtained suggest the involvement of reactive species in ALA-induced convulsions and may be of value in understanding the physiopathology of neurological dysfunctions associated to ALA overload.