The Geography of Phytochemical Races

68 2 Examples Within Continents
populations sampled for chemical work from Tibet (centered at ca. 28°N, 94°50′E)
and Yunnan Province (centered at ca. 27°N, 90°40′E), and samples of subsp. sinensis
coming from Gansu Province (centered at ca. 35°40′N, 104°E) and Liaoning
Province (centered at ca. 40°N, 120°E). A study of long-chain hydrocarbon derivatives
obtained from these two taxa revealed clear-cut differences between the two
(Tian et al., 2004). Tetracosane was present in both taxa but in signifi cantly higher
concentration in subsp. sinensis. The reverse was true for eicosanol where much
larger amounts were seen in subsp. yunnanensis. A further distinction was observed
with hexadecanoic acid, which was a major component in subsp. yunnanensis, but
not detected in subsp. sinensis. Further distinctions could be made between populations
from Tibet and Yunnan Province, and between populations from Gansu and
Liaoning Provinces based upon other constituents. These authors’ results were in
substantial agreement with the geographic patterning of features of growth and
plant hardiness reported by Yao and Tigerstedt (1995) and Yao et al. (1992).
2.5.8 Thujopsis dolabrata (Cupressaceae)
Thujopsis dolabrata Sieb. et Zucc., hiba, the sole species of the genus, is endemic to
Japan where it occurs on all major islands. Earlier reports, cited by Takahashi et al.
(2003), recorded the diterpene chemistry of leaves of T. dolabrata (structures not
shown here), and a level of variation that led to the present study which was based
on a much larger sampling of the species. Thus, over 220 individuals from 34 sites
were analyzed for their diterpene and diterpene acid content by GLC methods and
the data subjected to statistical analysis. Three types of T. dolabrata emerged from
the analysis which occupy more or less defi nable areas: Type I area is split between
Tohoku and Hokkaido (northern Japan), and the northern part of Chugoku; Type II
area lies in the central part of Japan; and the Type III area includes southeastern and
southern Japan. Figure 2.41.2 shows these areas.
2.6 South America
2.6.1 Vanillosmopsis erythropappa (Asteraceae)
Vanillosmopsis erythropappa Schultz-Bip. is a component of the Atlantic coastal
forest in Brazil, where it is exploited as a source of an essential oil used in the pharmaceutical
industry. A survey of specimens from four locations showed markedly
different compositions of their essential oil fraction (Lopes et al., 1991). The compounds
identifi ed were bisabolol [160], costunolide [161], eremanthine [162], and
fi ve related compounds, six compounds based upon the cyclocostunolide skeleton
[163], and the two esters 15-deoxygoyazenolide [164] and lychnopholide [165]