ABSTRACT
Objective: To investigate the antidiabetic effect of Rourea cuspidata hydroalcoholic stem extract in normal and streptozotocin-induced diabetic rats. Methods: In order to evaluate the chemical composition, different extracts from stem in ascending solvent order of polarity were prepared. The extracts were analyzed by high resolution mass spectrometry and 7 compounds were identified, including hyperin, an important and already reported active compound in the literature. Hyperin was also quantified by HPLC-UV in all the extracts. The hydroalcoholic stem extract (Ss5), which showed the highest concentration of hyperin, was administered to STZ-induced diabetes rats to evaluate the potential hypoglycemic activity. Total cholesterol, HDL, triglycerides, ALT and AST were also evaluated. In the present study, the effects of oral administration of hydroalcoholic stem extract (200 mg/kg b. wt.) for 28 days on the level of serum glucose, total cholesterol, HDL, triglycerides, aspartate amino transferase (AST) and alanine amino transferase (ALT) in normal and streptozotocin-induced diabetic rats were evaluated. Histopathological changes in diabetic rats' pancreas were also studied. Results: The extract exposition demonstrated hypoglycemic effect like the drug control glibenclamide. The extract was able to increase the HDL levels. Histopathological study on diabetic rats' pancreas after extract treatment showed morphological alterations in STZ-induced diabetes rats, which were apparently restored after extract treatment. Conclusions: This work demonstrates the potential use of R. cuspidata as hypoglycemic agent in the treatment of diabetes.
ABSTRACT
O objetivo deste trabalho foi avaliar a eficiência de dois planos de amostragem para análise de fumonisinas (B1+B2) em 11 lotes de milho. Empregaram-se o plano de amostragem manual em grãos inteiros, através do calador graneleiro e o plano de Amostragem Automático em Fluxo Contínuo em grãos moídos (AAFC). Para a comparação dos dois planos de amostragem, foram utilizadas duas medidas de dispersão: a variância e o coeficiente de variação. Em cada plano de amostragem, foram determinadas as variâncias associadas às três etapas do procedimento de detecção das fumonisinas (amostragem, preparação da amostra e análise) e os coeficientes de variação total. A correlação entre as médias de concentrações de fumonisinas e as variâncias de cada etapa do procedimento de detecção foi avaliada para cada plano amostral através da análise de regressão. Na AAFC de milho moído para análise de fumonisinas, obtiveram-se resultados inferiores (P<0,01) de variância na etapa de amostragem (0,0226mg kg-1)², assim como no coeficiente de variação total (6,37%), quando comparados com a variância da amostragem manual (0,0685mg kg-1)² e coeficiente de variação total do plano de amostragem manual em grãos inteiros (8,94%), apresentando, portanto, maior eficiência na detecção de fumonisinas em milho.
The aim of this research was to evaluate the efficiency of two sampling plans for fumonisins (B1+B2) analysis in 11 lots of maize. For sample collection the two systems used were a manual system in whole grains, using sampling spear, and an automatic system in milled grains, using the continuous flow sampling system (CFSS). For comparison purpose, two dispersion measurements were used: variance and coefficient of variation. For each sampling plan the variance associated to the three steps of fumonisins quantification (sampling, sample preparation, and analysis), and the total coefficient of variation were determined. The correlation between the average fumonisins concentration and the variances for each phase of the detection procedure was evaluated for each sampling plan using analysis of regression. At the automatic sampling plan in milled grains for fumonisins analysis in maize both sampling variance (0.0226mg kg-1)² and total coefficient of variation (6.37%) were lower (P<0.01) than in the manual sampling plan in whole grains whit (0.0685mg kg-1)² of variance and 8.94% of coefficient of variation, showing so better efficiency for fumonisin detection on maize.