I.M. Prosser et al. / Phytochemistry 67 (2006) 1564–1571
1571
was done by comparing spectra and KovatÕs retention
indices with published data (Adams, 2001), which defined
geometric isomers but not the absolute stereochemistry,
and by comparison of mass spectra and retention indices
with sesquiterpenes from C. bakerii (Kim et al., 1994).
Additionally, the samples were analysed using a Cyclo-
sil-B (J and W Scientific) chiral column. The temperature
programme was 50 ꢁC held for 2 min then an additional 3
ꢁC per min to 230 ꢁC which was held for 4.67 min. Terp-
enes were similarly extracted from 2 g C. bakerii leaf mate-
rial and analysed by GC–MS.
making available the Cupressus bakerii ssp. mathewsii
sample.
References
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4.10. Sesquiterpene synthase assays
For product identification, recombinant enzymes
were added to reactions containing sodium phosphate
pH 7.2 (20 mM), MgCl2 (5 mM), glycerol (10%),
[1-3H]FPP 850 GBq mmolꢀ1 (0.2 lM) and FPP (36
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Rothamsted Research receives grant-aided support
from the Biotechnology and Biological Sciences Re-
search Council (BBSRC), UK and this work was in part
supported by the Department of the Environment Food
and Rural Affairs (Defra), UK. We thank John Sim-
mons (Curator) Kew at Castle Howard, UK for kindly