Anti-plasmodial activity of extracts of five species of Icelandic liverworts

Liverworts (Hepaticae) belong to the bryophytes and count about six thousand species world wide. They are the structurally most primitive of the terrestrial plants, but they contain a complex array of secondary metabolites. About one thousand species of liverworts collected all over the world have been studied with respect to their chemistry, bioactivity, pharmacology, and application as sources of medicinal or agricultural drugs. They produce lipophilic mono-, sesqui-, and diterpenoids and aromatic compounds such as bibenzyls and bis-bibenzyls and to possess interesting pharmacological activity such as cytotoxic and anti-HIV properties, antimicrobial, antifungal and insect antifeedant activity [1,2,3].

The aim of this study was to determine the inhibitory activity of ethanol extracts from five species of Icelandic liverworts against the malaria parasite Plasmodium falciparum in an in vitro assay [4]. The five species of liverworts examined in this study are: Jungermannia exsertifolia, Chiloscyphus polyanthos, Leiocolea bantriensis, Marchantia polymorpha and Scapania undulata. All the extracts were tested in four different concentrations and showed good dose-dependent activity ranging from <12.5 to 34µg/mL. Leiocolea bantriensis showed the strongest activity with an IC₅₀ of <12.25µg/mL. The anti-plasmodial activity of liverworts has not been described in the literature before. The results encourage further investigation of anti-plasmodial active constituents from liverworts.

References: 1. Asakawa, Y. (2001) Phytochemistry 56: 297–312. 2. Asakawa, Y. (2007) Pure and Applied Chemistry 79: 557–580. 3. Nagashima, F. et al. (2005) Tetrahedron 61:4531–4544. 4. Ziegler, H. L. et al. (2002) Antimicrobial Agents and Chemotherapy 46:1441–1446.