Adinantum species are rich sources of triterpenes with various structural skeletons. Eighty-five triterpenoids were isolated from these species.
Most of the triterpenoids are pentacyclic and belong to the hopane and migrated hopane or closely related groups (Pan et al., 2011).
Examples of these triterpenes are shown in Table 1. A ditrerpene, 8,13-epoxy-14-labdan-19-oic acid, was identified from Adiantum emarginatum (Nguyen et al., 2008).
The whole plant of Adiantum caudatum yielded 16-hentriacontanone, hentriacontane and β-sitosterol (Singh et al., 1975).
The green fronds of Adiantum tetraphyllum yielded β-sitosterol and a mixture containing the ethyl esters of long-chain carboxylic acids (Melos et al., 2007). β-Sitosterol and β-sitosterol glucoside were also identified in Adiantum thalictroides var.
hirsutum (Erazo et al., 1991) and Adiantum caudatum (Gupta et al., 1990) respectively. Adian-5-ene ozonoid was isolated from the leaves of Adiantum monochlamys (Ageta et al., 1978; Shiojima et al., 1978).