Capillary Gas Chromatography-Mass Spectrometry (CGC-MS) Analysis and Antioxidant Activities of Phenolic and Components of Guarana and Derivatives

ABSTRACT

The GC-MS analysis of phenolic compounds present in guarana (Paullinia cupana), an important product of the Amazonian forest consumed in supplements or in soft drinks has been the subject of study. The therapeutic properties and possible protective effects reported for guarana and derivative products could be associated with the antioxidant activity of their phenolics content. The purpose of this study is i) to provide molecular structural information about the composition of guarana in phenolics; ii) to ascertain the effect of solvent type on the extraction procedure; and iii) to determine the antioxidant activity of powders, pericarp, pulp seeds, capsules and bar from Paullinia cupana, as oxygen radical absorbance capacity with fluorescein (ORACFL). Three more phenolic compounds, Quercetin, (+)-Catechin and (- )-Epicatechin have been identified in this report as trimethylsilyl (TMS) derivatives. The amount of total phenolics found in plant materials containing guarana varied from 25.10 to 124.99 mg of gallic acid/g dry sample whereas that the antioxidant activity ranged from 441.5 to 1468.3 μmol TEAC/g dry sample. A high correlation was found between the estimated phenolic contents and the TEAC values (r = 0.937, P< 0.01) for all the types of guarana samples tested.