The Chemical Composition of the Heartwood Extractives of Tamarack (Larix Laricina (Du Roi) K. Koch)

Abstract

The acetone-soluble constituents of tlie heartwood of taniaracli have been investigated. The flavanonols taxifolin ancl aromadcndrin were isolated in 0.30 and 0.05% yield and a trace amount of quercetin was obtained. Tropolo~ies could not be detectecl, nor was there any evidence for resin acids. The major portion of the extract consisted of esters of ferulic, phthalic, andlong-chain fatty acids. Eicosanylfcrulatewasisolatedassucli, whereas the other constituents were iclentified after saponification. Gas liq~lid cliromatograplly of the fatty acid mixture indicated tlie presence of palmitic, palmitoleic, oleic, linoleic, and linolenic acids as \\,ell as small amounts of CIi, stearic, and C~O acids. Fro111 the non-saponifiable portion p-sitosterol, eicosanol, and nonan-2-01 mere isolated. The acetone extract also contained free D-galactose and L-arabinose. INTRODUCTIONWhereas the heart\vood coilstituents of pine trees (1, 2) and those of the commercially important west coast conifers (1, 2, 3) have beell studied extensively, larch heartwood constituents have not been iilvestigated to ally great extent. Gripenberg (4) has isolated from Larix decidua (L. ez~ropea) taxifolin ((+)-2,3-clihydroquercetin) and aroillaclelldrin ((+)-2,3-dihydrokaeimpferol) and has shown that the distyliil isolated from L. leptolepis (5, 6) is a mixture of these two flavanonols (nomenclature (2)). Brewerton (7) made a thorough iilvestigatioil of the heartwood constituents of L. decidz~a ancl L. leptolcpis grown in New Zealancl ancl found, besides taxifolin and aromaclendrin, trace amoullts of a flavanoile (m.p. 252" C), a phytosterol, and unidentifiecl lignin-and tannin-like material, but no resin acids.Tamarack is a small-to medium-sized larch tree found across Canada from the Atla~ltic coast to northern British Columbia and in Alaska. The wood of this species is often quite oily and is resistant to decay. Although it is used for railway ties, telegraph poles, and posts, it has found little commercial use. The present study of the acetone-soluble heartnrood constitueilt was made on mature trees obtained from the Prince Albert and the Wiilnipeg areas. T h e freshly milled heartwood contained about 2.5% (on a dry weight basis) of acetone-soluble, non-volatile extractives.Prelimiilary investigation on the total extract and a saponified portioil thereof, by spot tests and paper chromatography, indicated the presence of a steroid, flavanoid constituents, and free sugars. Tropolo~les of the thujaplicin type were not detected on a paper cl~romatogram (g), nor were resin acids encountered. The conceiltrated acetone extract deposited a mixture of sugars, consisting of D-galactose (O.l.!iyo over-all yield, based on the dry weight of heart~vood extracted) and L-arabinose (0.04%). The extraction of these acetone-insoluble sugars is explaiiled by the presence of 15y0 moisture in the wood. The proportion of galactose to arabinose is the same as that found by Campbell et al. (9) in the €-galactan of larch wood (Larix decidz~a), ancl it is concei...

Lipophilic Extractives in Heartwood of European Larch (Larix decidua Mill.)

“…Nair and von Rudloff (1959Rudloff ( , 1960) studied and compared chemical composition of heartwood extractives of Tamarack (Larix laricina) and Alpine larch (Larix lyalii). Norin and coauthors (1965) determined the structures and confi gurations of the diterpenoids larixol, larixyl acetate and 13-epimanool, which were isolated from the oleoresin of European larch.…”

The Chemical Composition of the Heartwood Extractives of Larix Lyallii Parl.

“…1). I t .hydrolyzed with difficulty, causing considerable degradation of the ferulic acid moiety, and its infrared absorption spectrum was similar to that of the eicosculyl ferulate isolated from the heartwood of L. laricina (1). The 11011-saponifiable portion was co~nposed of a mixture of alcohols which failecl to crystallize and which could not be resolved by distillation.…”

Adipogenic constituents from the bark of Larix laricina du Roi (K. Koch; Pinaceae), an important medicinal plant used traditionally by the Cree of Eeyou Istchee (Quebec, Canada) for the treatment of type 2 diabetes symptoms

“…One study identified anti-tumor active principles [labdanetype diterpenes (Pichette et al, 2006)], while others studied the effect of the environment on phytochemicals components of Larix larix [volatiles (Nair and Von Rudloff, 1959;Von Rudloff, 1987;Powell and Raffa, 1999), phenolics (Niemann, 1969;Niemann and Bekooy, 1971) and diterpenes (Mills, 1973)]. Hence, ours is the first study that focuses on the identification of the active principles responsible for the adipogenic effect as putative antidiabetic mechanism of Larix laricina, as used by traditional Healers in Canadian Aboriginal populations.…”

“…In addition, significant amounts of rhaponticin (compound 9) were obtained from the fraction LLE-10. The known compounds 2-10 were identified by comparison of their spectroscopic data with those already reported in the literature (Nair and Von Rudloff, 1959;Caputo et al, 1973;Mills, 1973;Markham, 1976;Kashiwada et al, 1984;Rajasekhar and Subbaraju, 2000;Xie et al, 2003;Xue et al, 2004;Yang et al, 2005;Pichette et al, 2006;Chen et al, 2009;Pacheco et al, 2009). The identification of the new compound (compound 1) was conducted by 1D NMR ( 1 H, 13 C, DEPT) and 2D NMR (NOESY, COSY, HMQC and HMBC) analysis, as described further below.…”