First identification of natural products from the African medicinal plant Zamioculcas zamiifolia - A drought resistant survivor through millions of years.

Zamioculcas zamiifolia, an unusually drought resistant medicinal plant native to tropical east Africa and subtropical southeast Africa, including the countries Kenya, Malawi, Mozambique, South-Africa, Tanzania and Zimbabwe, is described as a living fossil which may have evolved as early as 42 million years ago. It belongs to the notoriously toxic family Araceae giving it, through association, a reputation for being toxic; despite little or no systematic evidence exists to support this claim. As an ancient plant it has sustained substantial climate changes and attacks from millions of generations of pathogenic microorganisms, which encouraged search for novel natural products from this source. Seven natural products have been characterized from leaves and petioles of Z. zamiifolia, including the novel main compound of the leaves, apigenin 6-C-(6″-(3-hydroxy-3-methyl-glutaroyl)-ß-glucopyranoside). The structure determinations were based on extensive use of 2D NMR spectroscopic techniques and high-resolution mass spectrometry. Initial toxicological experiment on extracts from Z. zamiifolia using brine shrimp lethality assay did not indicate lethality to the shrimps providing disproving evidence for the assumption of Z. zamiifolia's toxic character.