We report here for the first time, the results on the phenolic composition analysis of hot water and ethanol extracts of buds from sugar (Acer saccharum) and red maple (Acer rubrum), two dominant species of Laurentian forest of Quebec. The aim of the present study is to demonstrate the antioxidant capacity of these extracts while revealing their phenolic constituents. The extraction yields were determined for two types of buds based on the solvent used. Spectrometric methods were applied to quantify total phenols and different classes of polyphenols while the antioxidant capacity of the extracts was studied in vitro using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) test and Oxygen radical absorbance capacity (ORAC) assay. Higher extraction yields were obtained for red maple buds regardless of the solvent used. Hot water extraction yields were higher than ethanol extraction counterparts, for both maple buds studied. The spectrophotometric assays revealed that extracts from red maple buds contain higher concentration of total phenolics, flavonoids and anthocyanins while the concentrations of hydroxycinnamic acids and proanthocyanidins were higher in sugar maple bud extracts. Antioxidant capacity assays showed that, both sugar and red maple bud extracts presented real potential. Finally, strong relationships between the types and the amounts of phenolic compounds in maple buds and antioxidant capacity were determined. These results suggest that different valorisation fields for extracts from red and sugar maple buds could be anticipated.
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