One example is the study of Cetraria islandica complex: by a careful examination of over 3000 specimens, Kristinsson (1969) found that this group contained both fumarprotocetraric acid-producing and -deficient variants revealed by p-phenylenediamine spot testing, and that such chemotypes had no correlations with morphology and geography.
2001), which also leads to the discovery of two unusual fatty acids in the lichen Cetraria islandica: namely, octananedioic acid and nonanedioic acid.
Protolichesterinic acid is an aliphatic [gamma]-lactone with a methylene group on the [alpha]-carbon, consisting of two enantiomers: (+)-protolichesterinic acid 1 could be found in Cetraria islandica (Huneck and Yoshimura 1996) and Flavocetraria cucullata (Nguyen et al.
(+)-Lichesterinic acid 3 isolated from Cetraria islandica has a significant inhibitory activity on the growth of Trypanosoma brucei with an MIC value of 6.30 [micro]M compared to suramin (MIC = 10 [micro]M) as a positive reference (Igoli et al.
The extracts had a high total phenolic content, and the main constituents identified by HPLC were fumarprotocetraric acid in Cetraria islandica, and usnic, pinastric and vulpinic acids in Vulpicida canadensis.
The present work focuses for the first time on the possible neuroprotective and anticancer properties of the methanol extracts from two Parmeliaceae lichens from the cetraroid clade: Cetraria islandica and Vulpicida canadensis.
Comparing the retention times ([t.sub.R]) and UV spectra (190-400 nm) of the main peaks with those of reference substances previously isolated from lichens confirmed that the methanol extract of Cetraria islandica contains the depsidone fumarprotocetraric acid ([t.sub.R] = 26.397 min) as its main constituent (> 90% of total integrated area); it also contains traces of the related depsidone protocetraric acid ([t.sub.R] = 21.769 min).
Immunologically active (1 [right arrow] 3)-(1 [right arrow] 4)-[alpha]-D-glucan from Cetraria islandica
. Phytomedicine 6, 33-39.
In traditional medicine some lichen species such as Iceland moss, Cetraria islandica
, have been widely used for treating inflammatory conditions such as asthma and gastritis, as well as tuberculosis, without being associated with any adverse effects.
Ingolfsdottir K, Jurcic K, Wagner H (1998) Immunomodulating polysaccharides from aquous extracts of Cetraria islandica (Iceland moss).
Olafsdottir ES, Ingolfsdottir K, Barsett H, Paulsen BS, Jurcic K, Wagner H (1999a) Immunologically active (1[right arrow]3)(1[right arrow]4)-[beta]-D-glucan from Cetraria islandica. Phytomedicine 6: 33-39
Ingolfsdottir, K, Breu W, Huneck S, Gudjonsdottir GA, Wagner H (1994) In vitro inhibition of 5-lipoxygenase by protolichesterinic acid from Cetraria islandica
. Phytomedicine 1: 187-191