Isolation of phenolic compounds from hop extracts using polyvinylpolypyrrolidone: Characterization by high-performance liquid chromatography¿diode array detection¿electrospray tandem mass spectrometry

• Tipo: Artigo em Revista Científica Internacional
• Data: 2010

Autores

Magalhães, PJ (Autor) Outra; Vieira, JS (Autor) Outra; Gonçalves, LM (Autor) Outra; Pacheco, JG (Autor) Outra; Luis F Guido (Autor) FCUP; Barros, AA (Autor) Outra

Revista

Título: Journal of Chromatography A

Vol. 1217 Nº 43

Páginas: 3258-3268

ISSN: 0021-9673

Editora: Elsevier

Indexação

ISI Web of Knowledge - 26 Citações

ISI Web of Science

Scopus - 31 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia química

CORDIS: Ciências Físicas > Química > Química analítica > Espectroquímica ; Ciências Físicas > Química > Química aplicada > Química alimentar

Outras Informações

ID Authenticus: P-00H-8FE

DOI: 10.1016/j.chroma.2009.10.068

Abstract (EN): The aim of the present work was the development of a suitable methodology for the separation and determination of phenolic compounds in the hop plant. The developed methodology was based on the sample purification by adsorption of phenolic compounds from the matrix to polyvinylpolypyrrolidone (PVPP) and subsequent desorption of the adsorbed polyphenols with acetone/water (70:30, v/v). At last, the extract was analyzed by HPLC-DAD and HPLC-ESI-MS/MS. The first phase of this work consisted of the study of the adsorption behavior of several classes of phenolic compounds (e.g. phenolic acids, flavonols, and flavanols) by PVPP in model solutions. It has been observed that the process of adsorption of the different phenolic compounds to PVPP (at low concentrations) is differentiated, depending on the structure of the compound (number of OH groups, aromatic rings, and stereochemistry hindrance). For example, within the phenolic acids class (benzoic, p-hydroxybenzoic, protocatechuic and gallic acids) the PVPP adsorption increases with the number of OH groups of the phenolic compound. On the other hand, the derivatization of OH groups (methylation and glycosylation) resulted in a greatly diminished binding. The use of PVPP revealed to be very efficient for adsorption of several phenolic compounds such as catechin, epicatechin, xanthohumol and quercetin, since high adsorption and recovery values were obtained. The methodology was further applied for the extraction and isolation of phenolic compounds from hops. With this methodology, it was possible to obtain high adsorption values (>= 80%) and recovery yield values (>= 70%) for the most important phenolic compounds from hops such as xanthohumol, catechin, epicatechin, quercetin and kaempferol glycosides, and in addition it allows the identification of about 30 phenolic compounds by HPLC-DAD and HPLC-ESI-MS/MS.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 11