jf2048383_si_001.pdf (537.76 kB)
Characterization of Volatiles and Aroma-Active Compounds in Honeybush (Cyclopia subternata) by GC-MS and GC-O Analysis
journal contribution
posted on 2012-03-14, 00:00 authored by Maritha Le Roux, J. Christel Cronje, Barend
V. Burger, Elizabeth JoubertVolatile organic compounds (VOCs) in fermented honeybush, Cyclopia subternata, were sampled by means of a high-capacity
headspace sample enrichment probe (SEP) and analyzed by gas chromatography–mass
spectrometry (GC-MS). Stereochemistry was determined by means of enantioselective
GC-MS with derivatized β-cyclodextrin columns as chiral selectors.
A total of 183 compounds, the majority of which are terpenoids (103;
56%), were identified by comparing their mass spectra and retention
indices with those of reference compounds or tentatively identified
by comparison with spectral library or literature data. Of these compounds,
37 were determined by gas chromatography–olfactometry (GC-O),
using detection frequency (DF) and aroma extract dilution analysis
(AEDA), to be odor-active (FD ≥ 2). (E)-β-Damascenone,
(R/S)-linalool, (E)-β-damascone, geraniol, (E)-β-ionone,
and (7E)-megastigma-5,7,9-trien-4-one were identified
with the highest FD factors (≥512). The odors of certain compounds,
that is, (6E,8Z)-megastigma-4,6,8-trien-3-one,
(6E,8E)-megastigma-4,6,8-trien-3-one,
(7E)-megastigma-5,7,9-trien-4-one, 10-epi-γ-eudesmol, epi-α-muurolol, and epi-α-cadinol, were perceived by GC-O assessors as
typically honeybush-like.