The Geography of Phytochemical Races

4.2 Across the Indian Ocean (Primarily) 185
from the nineteenth century. Referring to Leptocarpus, a genus that in the older
treatment encompassed ten species from Australia, and one each from New Zealand,
Southeastern Asia, and Chile, now is considered to consist of three species. Former
members of the genus are now dispersed in Apodasmia, Dapsilanthus, and Stenotalis.
Flavonoid profi les now follow more closely the taxonomy of the genera rather than
their geographic location.
An interesting result of this taxonomic house cleaning is the disposition of the
Chilean taxon, which is now considered as Apodasmia chilensis (Gay) B. G. Briggs &
L. A. S. Johnson. Apodasmia is considered to consist of three species, the Chilean taxon
A. chilensis just noted, A. brownii (Hook. f.) B. G. Briggs & L. A. S. Johnson from
South Australia, Tasmania, and Victoria, and A. ceramophila from Western Australia.
A remarkable fi nding is the presence of a very unusual compound, gossypetin 7-methyl
ether 3-O-glucoside-8-O-galactoside [321] (the sugars may be reversed) in both the
Chilean and southeastern Australian species. It would seem remarkable were this very
unusual compound to occur by chance in two taxa separated by such distance; a close
relationship between these two species seems a reasonable possibility, one that might
well be addressed by macromolecular means.
The overall generic fl avonoid distribution from the two geographic areas can
best be appreciated by referring to the tabulated data from the recent Williams et al.
(1998) paper and the earlier study by Harborne (1979). This compilation, with the
compounds rearranged in increasing structural complexity, appears as Table 4.3.
Several signifi cant differences are evident among which is the very strong predominance
of fl avones in Australian species, 0.57–0.17 in the case of luteolin and a
Table 4.3 Distribution of fl avonoids in Restionaceae in Australia and Africa (from Williams
et al., 1998)
Compound Frequency of compound in species from
Australia Africa
Apigenin 0.01 0.02
Luteolin 0.57 0.17
Chrysoeriol 0.08 0.05
Tricin 0.17 nda Hypolaetin 0.48 nd
C-Glycosylfl avones 0.16 0.26
Kaempferol 0.09 0.10
Herbacetin 4′-methyl nd 0.07
Quercetin 0.30 0.31
Quercetin 3-methyl 0.01 nd
Isorhamnetin 0.09 nd
Myricetin 0.09 0.22
Larycitrin nd 0.24
Syringetin nd 0.21
Gossypetin 0.09 0.05
Gossypetin 7-methyl 0.03 0.10
Proanthocyanidins 0.04 0.88
Sulfated derivatives
a nd = not detected.
0.27 0.02