S. Buskov et al., Supercritical fluid chromatography as basis for identification and quantitative determination of indol-3-ylmethyl oligomers and ascorbigens, J BIOCH BIO, 43(1-3), 2000, pp. 175-195
Indol-3-ylmethylglucosinolate (glucobrassicin) occurs in most plants of the
Brassicaceae family together with hydroxy and methoxy derivatives of gluco
brassicin. These compounds and products produced therefrom have been the su
bject of considerable research interest due to their potential anticarcinog
enic effects, and thereby a need for techniques to work with the individual
compounds. A method using normal-phase supercritical fluid chromatography
(SFC) with methanol as modifier has been developed for determination and qu
antification of the various indol-3-ylmethyl derivatives including ascorbig
ens formed from the glucobrassicin degradation product, indol-3-ylmethanol,
under acidic conditions (pH 2-6) with and without the presence of ascorbic
acid, The SFC method had detection limits in the 10-100-pmol range. In the
absence of ascorbic acid a range of oligomers were formed, whereas the pre
sence of ascorbic acid favoured the formation of ascorbigen and products th
ereof. Quantitatively important indol-3-ylmethyl oligomers consisting of up
to five indol rings have been purified with preparative SFC and identified
from MS and 1D and 2D NMR experiments with complete assignment of chemical
shifts to all of the atoms. Investigation of the autolysis products of whi
te cabbage showed that ascorbigens were the quantitatively dominating degra
dation products of indol-3-ylmethylglucosinolates. (C) 2000 Elsevier Scienc
e B.V. All rights reserved.