Chemodiversity of Polynesian liverworts

Liverworts are known as rich sources of secondary metabolites, which volatile constituents such as terpenoids belong to a wide variety of carbon skeletons. These metabolites can be used as chemosystematics markers and are very helpful for taxonomic significance because liverworts are very small plants which morphological classification is extremely difficult. Aiming to assess the diversity of Polynesian liverworts, chemical analysis (GC-MS, 1D and 2D ¹H and ¹³C NMR) of volatile constituents of six species (Trichocolea pluma, Chandonanthus hirtellus, Mastigophora diclados, Jungermania sp., Plagiochila sp. and Cyathodium foetidissimum) collected in French Polynesia had been performed. All the investigated species are chemically different, each species biosynthesized own peculiar compounds and some of them are biomarkers of the liverworts species. T. pluma biosynthesized characteristic isoprenyl phenyl ethers, herbetane-type sesquiterpenoids for M. diclados, cembrane-type diterpenoid are peculiar for C. hirtellus and fusiccocane-type for Plagiochila sp. Interesting chemical constituents had been also in these Polynesian liverworts such as: vanillic acid methyl ester firstly reported to occur from the Marchiantophyta (T. pluma), skatol produced by C. foetidissimum, (E)-ectocarpene and dictyotene previously found in marine algae and now detected in C. hirtellus. These relevant findings express part of the biodiversity specificity of Polynesian bryophytes [1].

Acknowledgements: This work was supported in part by Grant-in-aid for Open Research (A.L.) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.

References: 1. Ludwiczuk, A. et al (2009), Nat. Prod. Com.10: 1387–1392.