Efeito do solvente na extração de ácidos clorogênicos, cafeína e trigonelina em Coffea arabica

Abstract

SOLVENT EFFECTS ON EXTRACTION OF CHLOROGENIC ACIDS, CAFFEINE AND TRIGONELLINE IN Coffea arabica.In this research work the effects of four solvents and their mixtures on the extraction of chlorogenic acids, caffeine and trigonelline in crude extracts of four coffee cultivars, traditional red bourbon, IAPAR59, IPR101 and IPR108 cultivars, were investigated by UV spectrophotometry and UV spectra obtained from RP-HPLC-DAD. The experimental results and the principal component analysis of UV spectra showed that the effect of solvent extraction of the metabolites does not depend on cultivars, because the spectral characteristics are similar, but the concentrations are different. The UV and UV-DAD spectra for four simplex centroid design mixtures were also similar but the concentrations of caffeine, trigonelline and the chlorogenic acids are different and depend on the solvent used in the extraction.Keywords: fingerprint; mixture design; Coffea arabica. INTRODUÇÃOOs grãos do café contêm proteinas, lipidios, ácidos nucleicos, carboidratos, clorofila, carotenóides, enzimas e hormônios. Quando torrados, estes constituintes são destruidos ou podem ser transformados em uma grande variedade de novos compostos. 1 Os grãos do café verde também contém compostos biologicamente ativos como a cafeína, ácidos clorogenicos (ACG), trigonelina, entre outros. Estes metabólitos são alguns dos precursores do aroma do café. 2 A trigonelina é rapidamente decomposta na torra do café em muitos componentes voláteis, mas mesmo assim é encontrada no café torrado em concentrações mais baixas. 1 Os ACG são os principais compostos fenólicos encontrados no café, sendo ésteres de ácidos trans-cinâmico tais como, ácidos cafeico, ferúlico e p-cumárico com ácido quínico. 3 São metabólitos secundários de grande interesse econômico porque também contribuem na formação de pigmentos e sabor dos grãos do café, determinando assim a qualidade e aceitação da bebida. A cafeína, por ser o principal metabólito fisiologicamente ativo e o alcalóide quantitativamente mais importante do café, foi e ainda é o mais estudado desde a sua descoberta e identificação. 1 As duas variedades comerciais mais importantes de café são a Coffea arabica e a Coffea canephora syn. Coffea robusta, sendo C. arabica de qualidade superior. Por esta razão, vários trabalhos relatam métodos para discriminar as duas espécies. 4-9 Embora existam milhares de artigos na literatura sobre cafés defeituosos e não-defeituosos, 10,11 propriedades antioxidantes dos metabólitos, 12 os efeitos do café na saúde, 13-15 os efeitos da torrefação dos grãos de café, 12 a qualidade da bebida, 16-20 entre outros, poucos são os relatos na literatura sobre o efeito do solvente na extração de ácidos clorogênicos, cafeína e trigonelina, principalmente na variedade Coffea arabica.Nos programas de melhoramento genético do café o objetivo é desenvolver diferentes cultivares para promover ganhos na produtividade e também agregar características agronômicas de resistência às pragas e doenças. Por outro lado, a composição...

Evaluation of some in vitro bioactivities of sunflower phenolic compounds

“…Relevant references to the subject have shown that the efficiency of the extraction solution for plant phenolic compounds depends on both the solvent and the matrix. According to Moreira et al (2014) , the best solvents to extract the chlorogenic acids from coffee beans were ethanol or a ternary mixture of ethanol: ethyl acetate: dichloromethane (1:1:1 v/v/v). Another study extracting the phenolic compounds from defatted sunflower meal, using: water; 70 mL/100 mL methanol; 70 mL/100 mL acetone, and a 70:30 mixture of ethyl acetate and water showed the water as the best extractor solvent ( Matthäus, 2002 ).…”

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“…S3, ESI†) demonstrate that the electrochemical thread in a tube microfluidic device displays a typical behavior of a conventional FIA system. 43,44 This is an important observation and demonstrates that the proposed microfluidic device is capable to maintain a consistent flow rate driving the analyte towards the detection zone.…”

Chemometric Analysis of UV Characteristic Profile and Infrared Fingerprint Variations ofCoffea arabicaGreen Beans under Different Space Management Treatments

“…Previous studies developed in our laboratory have shown the efficiency of these solvents and their mixtures in the extraction of coffee compounds. 21,33,34 The extractions were performed with 2.50 g of crushed beans and 60 mL of extracting solvent in ultrasonic bath (Ultracleaner 1400 Unique), for 120 min and maintained at 15 ± 2 °C with ice. After filtration, the filtrate was collected and the extraction cycle was repeated with the residue.…”

“…31 The spectra subjected to fingerprint analyses contain variance information that can be extracted using a wide variety of chemometric methods. [32][33][34] Multivariate analysis methods, such as principal component analysis (PCA) 35 and cluster analysis (CA), 36 allow dimensionality reduction of multivariate data and the extraction of essential results from large data sets. These analytical techniques can be associated with adequate methods of multivariate analysis for extracting information about the influence of the space management treatments, such as density and planting patterns, in the production of metabolites in Coffea arabica L. beans.…”