Methods for the extraction of phytochemicals from fibrous plants in the

Abstract

Methods and apparatus are provided for the recovery of organic compounds from fibrous plant materials. Organic compounds which can be recovered from the fibrous plant materials include plant metabolites, such as arabinogalactan and phenols, which can be isolated from the wood, for example, of the Western Larch and Tamarack tree varieties. In addition to the recovery of organic compounds from wood, fibrous wood products also may be isolated, in the form of a clean fiber that can be used, for example, as raw material in wood processing applications or in the manufacture of high quality paper products. In one embodiment, a fibrous plant material first is compressed, to recover a liquid exudate and a first pressed plant fiber product. Optionally, the fibrous plant material, such as wood particles, is compressed in the substantial absence of any added solvent, to produce a pure normal liquid exudate and a first pressed plant product. The first plant fiber product then may be impregnated with, for example, an aqueous solvent, to recover an extract liquor and impregnated plant fiber. The impregnated plant fiber then is compressed to recover a liquid pressate and a second pressed fiber product. Using these methods, in one embodiment, a substantially pure arabinogalactan exudate and a wood fiber product can be recovered from wood of the genus Larix, with minimal coextraction of phenols. Additionally, a variety of different plant metabolites may be isolated and/or identified from different kinds of woody plants using the methods and apparatus.