Glycyrrhetinic
acid is a pentacyclic
triterpenoid
amyrin derivative and obtained from
hydrolysis of
glycyrrhizic acid
[1]. It is used in
flavouring and it masks the bitter taste
of drugs like
aloe and
quinine. It is effective in the treatment of
peptic ulcer and as an
expectorant.
In
glycyrrhetinic acid the functional group (R)
is a
hydroxyl group. Research in 2005 [1] demonstrated that
with a proper functional group a very effective
glycyrrhetinic
artificial sweetener can be obtained. When
R is an
anionic NHCO(CH2)CO2K
side chain, the sweetening effect is found to 1200 times that of
sugar (human sensory panel data). A shorter or longer spacer
reduces the sweetening effect. One explanation is that the
taste bud cell
receptor has 1.3
nanometers (13
angstroms) available for docking with the sweetener molecule (lock-and-key
model). In addition the sweetener molecule requires three
proton donor positions of which two reside at the extremities to be
able to interact efficiently with the receptor cavity.