25 research outputs found
Antioxidant capacity and bioactive compounds of four Brazilian native fruits
The purpose of this study was to evaluate the bioactive compounds and antioxidant activity of extracts from araçá (Psidium cattleianum), butiá (Butia eriospatha), and pitanga (Eugenia uniflora) fruits with different flesh colors (i.e., purple, red, and orange), and blackberries (Rubus sp.; cv. Xavante and Cherokee) collected in the southern region of Brazil. The content of ascorbic acid, total carotenoids, and phenolics were determined. The profile of the phenolic compounds was assessed by high-performance liquid chromatography combined with diode array detection (HPLC-DAD). The antioxidant activity was determined using the ferric-reducing antioxidant power (FRAP) assay, 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) assay, total reactive antioxidant potential (TRAP) assay, and total antioxidant reactivity (TAR) assay. The Xavante blackberry and purple-fleshed pitanga showed the highest total phenolic content [816.50 mg gallic acid equivalents (GAE)/100g and 799.80 mg GAE/100g, respectively]. The araçá and red-fleshed pitanga showed the highest carotenoid content (6.27 ug β-carotene/g and 5.86 ug β-carotene/g, respectively). The fruits contained several phenolic compounds such as quercetin derivatives, quercitrin, isoquercitrin, and cyanidin derivatives, which may contribute differentially to the antioxidant capacity. The highest scavenging activity in the DPPH assay was found for purple-fleshed pitanga (IC50 36.78 mg/L), blackberries [IC50 44.70 (Xavante) and IC50 78.25 mg/L (Cherokee)], and araçá (IC50 48.05 mg/L), which also showed the highest FRAP, followed by orange- and red-fleshed pitanga. Our results revealed that some fruits grown in southern Brazil such as purple-fleshed pitanga, blackberries, and araçá are rich sources of phenolic compounds and have great antioxidant activity
Controle da leptospirose em bovinos de leite com vacina autógena em Santo Antônio do Monte, Minas Gerais
Um surto de leptospirose foi observado em bovinos leiteiros em Santo Antônio do Monte, Minas Gerais. O rebanho apresentava reações positivas anti-leptospira sorovar Hardjo no teste de microaglutinação (MAT) e havia sido vacinado anteriormente com vacina experimental contendo a sorovariedade Hardjo. O MAT revelou 48,06% dos bovinos positivos para sorovariedade Hardjo genótipo Hardjobovis, 36,82% para sorovariedade Hardjo genótipo Hardjoprajitno. Os animais apresentavam aborto e mastite com presença de sangue no leite. A presente pesquisa teve como objetivos isolar as sorovariedades existentes a partir da urina de vacas sorologicamente positivas, elaborar uma vacina experimental com as sorovariedades isoladas no rebanho, avaliar a eficiência do programa de vacinação por um período de dois anos por meio da sorologia do rebanho. Foi isolada Leptospira spp. a partir da urina de duas vacas com sinais sugestivos da doença. As amostras isoladas foram identificadas pela sorologia com anticorpos monoclonais e seqüenciamento do gene 16S rRNA como pertencentes à espécie Leptospira interrogans, sorogrupo Sejroe, sorovariedade Hardjo e genótipo Hardjoprajitno. O uso da vacina autógena foi eficaz no controle da leptospirose no rebanho no período de dois anos. Os resultados da sorologia revelaram ausência de animais positivos na última prova realizada no rebanho
Variabilidade isoenzimática entre linhagens de amendoim resistentes à seca Isoenzimatic variability between peanut lines resistant to drought
O uso da técnica de eletroforese para separar múltiplas formas moleculares de enzimas tem sido bastante explorada na área biológica, cujas diferenças detectadas nos tecidos podem ser eficientemente usadas para diferenciação de cultivares em qualquer fase de seu desenvolvimento fenológico. Nesse trabalho, procedeu-se ao estudo da variabilidade isoenzimática em seis linhagens de amendoim resistentes à seca, com o objetivo de se verificar as possíveis relações da variação encontrada na base desses descritores com essa aptidão no amendoim. Estudaram-se folíolos da parte apical com 5 dias após a germinação, utilizando-se a técnica de eletroforese em gel de poliacrilamida (7%) sistema horizontal e contínuo de tampão. Os sistemas estudados foram fosfatase ácida (ACP), malato desidrogenase (MDH), leucina aminopeptidase (LAP), peroxidase (PO), e esterase (EST). A caracterização fenotípica dos genótipos permitiu a separação de quatro grupos para ACP, três para LAP, dois para MDH e seis para PO e EST. A partir da análise dos componentes principais dos grupos obtidos, observou-se que a cultivar IAC Tupã (sensível à seca) foi separada das demais, especialmente da cultivar resistente Senegal 55437.<br>The use of electrophoretic techniques to separate multiple molecular forms of enzymes has been used in the biological science, where differences in isozymes among tissues can be used efficiently on cultivar differentiation during any life cycle phase. In this paper, the variability of six drought resistant peanut lines was studied by isozymes analysis aiming to verify the possible relations between enzymatic descriptors and drought resistance character. Leaflets were analyzed by horizontal poliacrylamide gel electrophoresis technique and buffer continuos systems for the following systems: acid phosphatase (ACP), malate dehydrogenase (MDH), leucine aminopeptidase (LAP), peroxidase (POX) and esterase (EST). The phenotypic characterization of the genotypes allowed four group separations to ACP, three to LAP, two to MDH, and six to POX and EST. The IAC Tupã cultivar (drought sensitive) was differentiated to the others genotypes, specially as to Senegal 55 437 cultivar (drought resistant) by principal components analysis
Development of standardized extractive solution from Lippia sidoides by factorial design and their redox active profile
AbstractThe aim of this study was to evaluate the influences of variables of preparation on total flavonoids content from extractive solution of Lippia sidoides Cham., Verbenaceae. Thus a 23 factorial design was used to study the importance of plant proportion, the extraction method and solvent on the extraction of flavonoid. The methodology of determination of chemicals in factorial design was validated according to the parameters required by Brazilian Health Agency. The extraction solution was selected through a full factorial design where the best conditions to achieve the highest content of flavonoids were: 7.5% (w/v) of plant with ethanol 50% (v/v) as solvent. The polyphenols content was determined by LC method and its relationship with the antioxidant and free radical scavenging activities was evaluated. The free radical scavenging activities and antioxidant potentials were determined for different concentrations using various in vitro models. Our results indicate that extracts exhibited a significant dose-dependent antioxidant effect as evaluated by TRAP/TAR assays. Besides, we observed an antioxidant activity against hydroxyl radicals and nitric oxide, and protection against lipid peroxidation in vitro. Our results suggest that the extract presents significant in vitro antioxidant potential indicating promising perspectives for its use as pharmaceutical/or food additive