EXTRACTIVES FROM NEW-ZEALAND HONEYS .4. LINALOOL DERIVATIVES AND OTHER COMPONENTS FROM NODDING THISTLE (CARDUUS-NUTANS) HONEY

Sixteen linalool derivatives and a variety of aliphatic acids and diacids, aromatic acids, and phenols (total of 61 components) were identified in the methylated diethyl ether extracts of New Zealand nodding thistle (Carduus nutans) honeys using GC-FID and combined GC-MS methods. Separation of the diethyl ether extracts afforded three dominant linalool derivatives which were identified using one- and two-dimensional NMR procedures as (E)-2,6-dimethyl-3,7-octadiene-2,6-diol (3), (Z)-2,6-dimethyl-6-hydroxy-2,7-dienal (8), and (E)-2,6-dimethyl-6-hydroxy-2,7-octadienoic acid (characterized as methyl ester, 6). The minor components, alpha,5-dimethyl-5-ethenyl-2-tetrahydrofuranacetaldehydes [lilac aldehydes (11), four isomers] and beta,5-dimethyl-5-ethenyl-2-tetrahydrofuranethanols [lilac alcohols (10), four isomers], were identified by comparison with synthetic samples. The total level of linalool derivatives in the nodding thistle honey samples was between 15 and 87 mug/g of honey (average level 43 mug/g of honey).