5 documents found, page 1 of 1
What is new in non-chromatographic flavonoid purification?
Aguiar,Leonardo de Oliveira; D’Onofrio,Clara Ribeiro do Espírito Santo; David,Jorge MauricioFlavonoids are metabolites occurring in all plant tissues and present different biological activities. They occur in a mixture of similar polarity with laborious separation and purification processes, usually furnishing low yields. Semi-preparative chromatographic methods are universally employed procedures for their isolation. This paper discusses the state-of-the-art in new non-chromatographic techniques for ...
Optimization of a technique to quantify the total phenolic compounds in jambola...
Brandão,Taís Silva de Oliveira; Pinho,Lorena Silva; Teshima,Elisa; David,Jorge Mauricio; Rodrigues,Maria IsabelAbstract There are various known extraction methods that can be applied to the quantification of phenolic compounds, and thus it is up to the researcher to perfect the process that best applies to the sample in question. Different extraction solvents (liquid-liquid extraction) were compared in order to assess their effectiveness for the analysis of total phenols in jambolan ( Syzygium cumini Lamark) pulp extrac...
Composição química, atividade citotóxica e antioxidante de um tipo de própolis ...
Santos,Darlan C. dos; David,Jorge Mauricio; David,Juceni PereiraPropolis is a complex mixture composed by salivary secretions of bees and a resinous and balsamic material collected by them from different part of plants. This material is well employed by people due its antimicrobial, antioxidant, anti-inflammatory, antiviral properties beside others. However, the chemical composition varies according the habitat and season. This work describes the identification of saturated...
Atividade anticolinesterásica e perfil químico de uma fração cromatográfica ati...
Marques,Thiago Henrique Costa; Santos,Pauline Sousa dos; Freitas,Rivelilson Mendes de; Carvalho,Rusbene Bruno Fonseca de; Melo,Cassio Herbert Santos deThis work describes the isolation of an active flavonoid fraction and identification of isorhamnetin 3-O-β-D-(6''-acetyl)-galactopyranoside from flowers of B. perennis, and also the evaluation of anticholinesterase (AChE) activity of ethanolic extract from flowers (EEF) and the active fraction. The chemical structure of the flavonoid was defined on the basis of spectroscopic ¹H NMR, IR and UV data. EEF or flavo...
Composição química e atividade anticolinesterásica de uma fração ativa do extra...
Carvalho,Rusbene Bruno Fonseca de; Almeida,Antonia Amanda Cardoso de; Freitas,Rivelilson Mendes de; Lima,Luciano Silva; David,Juceni PereiraThis paper describes the chemical composition and acetylcholinesterase inhibition of an active chromatographic fraction of the EtOAc extract of Citrus limon leaves. The composition of the active fraction presented a mixture of two coumarins, 5,8-dimethoxy-psoralen and 5,7- dimethoxycoumarin, identified by ¹H and ¹³C NMR data analysis, including DEPT, COSY, HMBC and HSQC experiments. It was also demonstrated tha...