Composition of ethanolic extracts of wood and bark from Acer saccharum and Betula alleghaniensis trees of different vigor classes

Abstract

The forest populations of Acer saccharum Marsh and Betula alleghaniensis Britton of south west Québec contain a significant proportion of low vigor trees, which are prioritized for harvesting as part of a forest restoration plan. Ethanol extractions of bark and wood collected from vigorous and non-vigorous trees were performed in order to compare their chemical compositions and thus evaluate the potential of adding value to the processing of low-vigor trees. Two methods – maceration and ultrasound assisted solvent extractions – were applied. Total content of phenols, proanthocyanidins, hydroxycinnamic acids and flavonoids were determined in the extracts by spectrophotometric methods. Concentrations of selected triterpenes and sterols were evaluated by GC–MS. While some variation in extract yields, polyphenol and lipophilic content was detected between vigorous and non-vigorous trees, the overall composition of extracts remained similar across vigor classes. The two extraction methods yielded very similar results while the advantage of the ultrasound assisted method was a much shorter extraction time. Ultrasound assisted ethanolic extraction of potentially valuable compounds could therefore be considered as an option to add value to the processing of low vigor A. saccharum and B. alleghaniensis trees.