Navegando por Autor "POMPEU, Darly Rodrigues"

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Acesso aberto (Open Access)
Capacidade antioxidante e triagem farmacológica de extratos brutos de folhas de Byrsonima crassifolia e de Inga edulis
(Instituto Nacional de Pesquisas da Amazônia, 2012-03) POMPEU, Darly Rodrigues; ROGEZ, Hervé Louis Ghislain; MONTEIRO, Karin Maia; TINTI, Sirlene V.; CARVALHO, João Ernesto de
In order to evaluate the effect of two Amazonian species on chronic diseases linked with the oxidative processes, we performed antioxidant capacity analyses (Oxygen Radical Absorbance Capacity - ORAC and Folin-Ciocalteu - PT assays) and pharmacological effects in vitro (antiproliferative effect) and in vivo (antinociceptive, antiinflammatory, antiulcerogenic effects) for ethanolic extracts (65:35; v/v; ethanol:water) from Byrsonima crassifolia (BC) and Inga edulis (IE) leaves. Both BC and IE extracts showed high ORAC values (1,422 and 694 mmol of Trolox equivalent/g of dry leaf, respectively) and high PT contents (35.93 and 24.50 mg gallic acid equivalent g-1 dry leaf, respectively). The ORAC values had no correlation with PT, suggesting the presence of other chemical groups in the antioxidant activity value. The two extracts did not present significant antiproliferative activity on nine lines of human tumor cells, and cytotoxic effect was detected only at the highest concentration. The antinociceptive effect was investigated using the hot plate test, and IE extract presented a longer latency (P < 0.05) 30 and 60 min after oral administration. The antiinﬂammatory activity was only observed at the highest concentration, suggesting that the antinociceptive effect observed was not due to the antiinflammatory effect. The extracts of both species reduced the ulcerative lesions produced by ethanol up to 84% (P < 0.05), suggesting a relation with the antioxidant capacity. More studies are necessary to elucidate the mechanisms of action involved on antiulcerative effects.
Acesso aberto (Open Access)
Farinha de mandioca (Manihot esculenta) e tucupi: uma abordagem analítica utilizando espectroscopia no unfravermelho próximo (NIRS) e ferramentas quimiométricas
(Universidade Federal do Pará, 2022-04-25) POMPEU, Darly Rodrigues; SOUZA, Jesus Nazareno Silva de; http://lattes.cnpq.br/3640438725903079; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423
The near infrared spectroscopy (NIRS) coupled to chemometrics has been used as an alternative tool for quick and reliable solutions. Cassava flour (CF) can be classified as fermented and non-fermented types. Tucupi is a yellow broth, acidic, mostly aromatic and widely used in Regional dishes in Para state. This thesis proposed to apply for the first time the NIRS associated with chemometrics to predict quality parameters from CF and tucupi, as well as to discriminate fermented and non-fermented CF. One hundred six samples of CF was investigated and nine physicochemical parameters of CF were evaluated. Calibration equations with independent validation were developed to predict all parameters using the partial least square regression method. The performance of models was evaluated by the root mean standard error of calibration (RMSEC) and validation (RMSEV), and R2 values. The aW (RMSEC = RMSEV = 0.05), moisture content (RMSEC = 0.35%; RMSEV = 0.45%) and pH (RMSEC = 0.16; RMSEV = 0.18) could be predicted (R2 > 0.727) by NIRS coupled to multivariate analysis. NIRS coupled to Principal Component Analysis–Linear Discriminant Analysis (PCA-LDA) was also used to investigate the classification of fermented and unfermented CF. The use of NIRS spectra allows to obtain better performance parameters (training accuracy: 86.3–93.8%; validation accuracy: 84.6–96.2%) to discriminate fermented and unfermented CF than the use of the physicochemical properties (training accuracy: 80%; validation accuracy: 84.6%). NIRS was also used to predict nine quality physicochemical properties of tucupi Sixty-five samples of tucupi were used in this study. The performance of models was evaluated by the R2, RMSEC, root mean standard error of cross-validation (RMSECV) and RMSEV values. The total soluble solids contents could be predicted (R2 > 0.727; RMSEC = 0.184%; RMSECV = 0.411%; RMSEV = 0.338%) by NIRS coupled to multivariate analysis. NIRS and chemometrics proved to be a powerful tool to predict quality parameters in CF and tucupi as well as to discriminate fermented and non-fermented CF.