inflammatory, antiulcerogenic, antibacterial, antifungal, and antirheumatic
activities [90].
Brassicasterol
Brassicasterol (Fig. 27) known in higher plant is also found in the various lichens
[90]. In acetone extract of the lichen Stereocaulon azoreum were identified several
substances by column chromatography. In addition to the main compounds, three
sterols such as brassicasterol, ergosterol peroxide, and cerevisterol were
obtained [92].
Ergosterol
It has been demonstrated in previous studies that sterols may play a role in the
membrane permeability in the lichen thallus. The content of ergosterol (Fig. 28)
(Ergosta-5,7,22-trien-3β-ol) in the lichens, which is the major sterol of the fungal
plasma membrane, responds rapidly to the presence of xenobiotics in the environment, including the presence of heavy metals. Ergosterol can be considered as
marker of the fungal metabolic activity [93].
Fig. 25 Phytol structure (Anaptychia ciliaris)
Fig. 26 Zeorin structure (Protoparmeliopsis muralis)
9 Lichen Metabolites: An Overview of Some Secondary Metabolites and Their. . .
197
activities [90].
Brassicasterol
Brassicasterol (Fig. 27) known in higher plant is also found in the various lichens
[90]. In acetone extract of the lichen Stereocaulon azoreum were identified several
substances by column chromatography. In addition to the main compounds, three
sterols such as brassicasterol, ergosterol peroxide, and cerevisterol were
obtained [92].
Ergosterol
It has been demonstrated in previous studies that sterols may play a role in the
membrane permeability in the lichen thallus. The content of ergosterol (Fig. 28)
(Ergosta-5,7,22-trien-3β-ol) in the lichens, which is the major sterol of the fungal
plasma membrane, responds rapidly to the presence of xenobiotics in the environment, including the presence of heavy metals. Ergosterol can be considered as
marker of the fungal metabolic activity [93].
Fig. 25 Phytol structure (Anaptychia ciliaris)
Fig. 26 Zeorin structure (Protoparmeliopsis muralis)
9 Lichen Metabolites: An Overview of Some Secondary Metabolites and Their. . .
197