The Leaf, Wood and Bark Oils of three Species of Myodocarpus (Myodocarpaceae) Endemic to New Caledonia

Abstract

The leaf, wood and bark oils of three species of Myodocarpus, M. viellardii Brongn. & Gris, M. fraxinifolius Brongn. & Gris and M. lanceolatus Dubard & R. Viguier have been examined. From the wood oil of M. viellardii the major components were α-pinene (22.4%) and a monoterpene methyl ester, methyl myodocarpate (methyl 3,7-dimethylbicyclo [4,1,0]hept-3-ene-7-carboxylate) (61%), based on the δ-3-carene skeleton. Also present in lesser amounts was the corresponding acid, myodocarpic acid (3,7-dimethylbicyclo[4,1,0]hept-3-ene-7-carboxilic acid) and the corresponding alcohol, myodocarpol (3,7- dimethylbicyclo[4,1,0]hept-3-en-7-yl) methanol), in lesser (< 3%) amounts. The bark oil contained β-caryophyllene (13.8%) and a series of long chain fatty alcohols, dodecanol, tetradecanol, hexadecanol, octadecanol and octadec-9-en-1-ol in amounts of 1.4-15% (all but octadecanol > 11%). The leaf oil of this species produced a sesquiterpenic oil with the principal components being β-caryophyllene (36%), α-humulene (11.1%) and bicyclogermacrene (10.6%). In M. fraxinifolius, both the wood and bark oils contained a series of long chain alcohols, tetradecanol (30-38%), hexadecanol (23-29%) and octadec-9-en-1-ol (12%) as principal components. In the leaf oil of this species the principal component was β-caryophyllene (63%), with lesser amounts of humulene oxide II (2.9%), isocomene (2.8%) and viridiflorol (1.4%). In M. lanceolatus, the leaf oil was dominated by the monoterpene hydrocarbons α-pinene (22.9%) and δ-3-carene (32.6%). In the wood oil of this species the principal components were geraniol (7.4%), citronellol (4.7%), germacrene-B (7.1%), zingiberine (6.8%) and linalool (6.7%), while in the bark oil they were geraniol (12.4%), citronellol (2.6%), germacrene-B (5.8%), and linalool (6.5%).