Leandro Freire dos Santos

Glucose administration inhibits the hepatic activation of gluconeogenesis promoted by insulin-induced hypoglycemia

The activation of hepatic gluconeogenesis in male Wistar adult 6 h fasted rats during insulin-induced hypoglycemia (IIH) was previously demonstrated. In this study, the effects of intraperitoneal (ip) glucose (100 mg/kg) on the activation of liver gluconeogenesis during IIH was investigated. Thus, 6 h fasted rats that received ip regular insulin (1 U/kg) and 30 min later ip saline (Control group) or glucose (Experimental group) were compared. All the experiments were executed 60 min after insulin injection. The glycemia of Control and Experimental groups were not different (P > 0.05). To investigate gluconeogenesis, liver perfusion experiments were performed. The results demonstrated that excepting glycerol, livers from rats which received ip glucose showed lower (P < 0.05) gluconeogenesis from L-alanine, L-glutamine, L-lactate or L-alanine + L-glutamine + L-lactate + glycerol. Therefore, the absence of glucose recovery after the glucose administration was mediated, at least in part, by an inhibition of hepatic gluconeogenesis.

Lactose hydrolysis potential and thermal stability of commercial β-galactosidase in UHT and skimmed milk

The commercial enzyme (E.C. = 3.2.1.23) from Kluyveromyces lactis (liquid) and Aspergillus oryzae(lyophilized) was investigated for its hydrolysis potential in lactose substrate, UHT milk, and skimmed milk at different concentrations (0.7; 1.0 and 1.5%), pH values (5.0; 6.0; 6.5 and 7.0), and temperature (30; 35; 40 and 55 oC). High hydrolysis rates were observed for the enzyme from K. lactis at pH 7.0 and 40 oC, and from A. oryzae at pH 5.0 and 55 oC. The enzyme from K. lactis showed significantly higher hydrolysis rates when compared to A. oryzae. The effect of temperature and β-galactosidase concentration on the lactose hydrolysis in UHT milk was higher than in skimmed milk, for all temperatures tested. With respect to the thermal stability, a decrease in hydrolysis rate was observed at pH 6.0 at 35 oC for K. lactisenzyme, and at pH 6.0 at 55 oC for the enzyme from A. oryzae. This study investigate the hydrolysis of β-galactosidase in UHT and skimmed milk. The knowledge about the characteristics of the β-galactosidase fromK. lactis and A. oryzae enables to use it most efficiently to control the enzyme concentration, temperature, and pH in many industrial processes and product formulations.

Hypolipidemic and Antiatherosclerotic Potential of Pleurotus ostreatus, Cultived by Submerged Fermentation in the High-fat Diet Fed Rats

The ability of Pleurotus ostreatus biomass, cultived by submerged fermentation, to produce beneficial effect on lipid profile and macrophages activity during a high-fat diet (HFD) for a long-term intake was investigated. Blood samples were collected through cardiac puncture to measure the plasma cholesterol, triglycerides, low-density protein (LDL), high-density protein (HDL), aspartate aminotransferase (AST) activity, urea-blood urea nitrogen (BUN)/creatinine ratio of rats fed on an HFD for 4 months. Dosage of lipid hydroperoxides was carried out on methanolic extract of liver tissue. Peritoneal macrophages activity was evaluated in relation to the superoxide anion, hydrogen peroxide and nitric oxide production, phagocytosis and lysosomal volume. The administration of P. ostreatus significantly altered the lipid profile and oxidative stress as related to the LDL and triglycerides decrease and inhibitory effects on superoxide anion and hydrogen peroxide production. All findings of this study lead us to suggest that the P. ostreatus maybe a beneficial agent in the hyperlipidemia and atherosclerosis treatments.

Antidiabetic activities of ethanol extract of dry matters of culture broth of Coriolus versiolor in submerged culture

The study aimed to investigate the antihyperglycemic and antilipidperoxidative effects of ethanol extract of the dry matter from culture broth of Coriolus versicolor (ECBC) in streptozotocin-induced diabetes mice. Blood glucose level, insulin level, total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol(LDL-C), high density lipoprotein -cholesterol (HDL-C) in serum and reduced glutathione level (GSH), lipid peroxidation, glycogen, antioxidant enzymes in liver were evaluated. Moreover, histopathological observation was conducted. Streptozotocin treatment (150 mg/kg body weight) induced the decrease of GSH level, antioxidant enzymes activities, glycogen content in liver, HDL-C content and insulin level in serum, accompanied by the elevation of the lipid peroxidation in liver, serum blood glucose level, contents of TC, TG and LDL-C. Treatment with ECBC restored the changes in the above parameters up to the basal level. The protective effects were further supported by the attenuation of the degree of pancreas damage in ECBC treated mice.

Dynamics of Ethanol Production from Deproteinized Whey by Kluyveromyces marxianus: An Analysis About Buffering Capacity,Thermal and Nitrogen Tolerance

The production of value-added products could be a valuable option for cheese wastewater management. However, this kind of study cannot just focus alone on getting the final product. This also necessitates studies on the dynamics of bioprocesses. With these as background, the present investigation aimed at evaluating the buffering capacity of deproteinized whey and effect of temperature and nitrogen source on ethanol yields from it. The batch fermentation conditions used to evaluate ethanol production were temperatures 30, 35, 40°C and pH 4.5, 5.0, 5.5, 6.0. To study the influence of nitrogen source on ethanol yield, a design matrix was applied using yeast extract and (NH4)2SO4.The final pH was analyzed to evaluate the buffering capacity. The results showed that the Kluyveromyces marxianus was thermotolerance to produce ethanol at 35 and 40°C, which was not observed at 30°C. Results also showed that the deproteinization procedure did not affect the buffering capacity of cheese whey. Finally, higher ethanol production was obtained using yeast extract (3% v/v). These results could be important for developing low-cost method for industrial production of ethanol from deproteinized whey.

Addition of Whey Protein in Bread-Making: Textural Parameters and Antioxidant Potential of Leavened and Unleavened Bread

Abstract The purpose of the study was to determine (1) whether baking process (a unit operation) – applied to produce leavened (LFB) and unleavened bread (UFB) – modifies the bioactivity of whey protein (WP) added in these portions and (2) how whey protein can change the textural parameters of these formulations. Reducing power activity (antioxidant potential) in food matrix was evaluated using phosphomolybdenum method. Textural parameters – hardness, cohesiveness, springiness, resilience, chewiness and gumminess – were carried out on a texture analyzer. In addition, this study demonstrated that the biofunctionality of whey protein was maintained in UFB 10 % WP. Nonetheless, this same formulation showed high values of textural parameters (hardness, chewiness and gumminess). Regarding the LFB formulations, the antioxidant potential was restricted after baking process in LFB 10 % WP. In conclusion, addition of bioactive additive in food matrix may not be sufficient to turn it into a functional food considering the effect of unit operations on bioactivity of some potential additives.

Cordyceps spp. e sua Participação no Sistema Reprodutivo Animal

O presente estudo foi realizado com o objetivo de verificar a influencia de residuos orgânicos no crescimento e na nutricao de mudas de Calophyllum brasiliense Cambess. As mudas de C. brasiliense foram produzidas em canteiro com areia e, apos periodo de incubacao, foram transplantadas para os tubetes. Os residuos orgânicos foram misturados em diferentes proporcoes ao substrato comercial Basaplant® e solo, em tubetes com capacidade para 240 cm³. O delineamento utilizado foi o inteiramente casualizado com 23 tratamentos e quatro repeticoes. Foram avaliados: altura, diâmetro de coleto, biomassa e a concentracao de nutrientes. A influencia dos substratos no crescimento das mudas de C. brasiliense dependera das combinacoes e proporcoes de residuos. No entanto, as combinacoes nao foram eficientes na disponibilizacao de N, Ca e Cu, devendo-se atentar para possiveis elevacoes nas concentracoes de macronutrientes que podem provocar sintomas de toxidez nas plantas.Esta revisao descrevera brevemente a relacao entre o Cordyceps spp. e sua participacao no sistema reprodutivo animal. Recentemente, estudos reportaram que ratos tratados com o Cordyceps sinensis apresentaram capacidade esteroidogenica aumentada. Assim, esta revisao providenciara uma perspectiva atual sobre as ultimas pesquisas que abordam tal assunto e suas implicacoes no tratamento complementar da andropausa. Outros aspectos basicos tambem serao discutidos como os androgenios.

Cordyceps sinensis biomass produced by submerged fermentation in high-fat diet feed rats normalizes the blood lipid and the low testosterone induced by diet

This study investigated the effect of Cordyceps sinensis biomass supplementation obtained from submerged fermentation on blood lipid and low testosterone induced by high-fat diet (HFD). The experiments were carried out using a long-term intake of HFD and HFD plus Simvastatin or C. sinensis (4 months). Our results show that plasma cholesterol, triglycerides and LDL were decreased by Cordyceps sinensis biomass supplementation (CSBS). A long-term intake of HFD caused a significant liver damage which has been reverted by CSBS. CSBS normalized decreasing testosterone levels observed in high-fat diet feed rats. All these findings lead us to suggest that C. sinensis was able to decrease blood lipid concentration, increase hepatoprotective activity and normalize testosterone levels.