Systematics, Sustainable Use and Conservation of Tribe Ocimeae (Basil and Allies, Lamiaceae) - COMPLETED
Basils and their allies, classified as tribe Ocimeae in the Lamiaceae, subfamily Nepetoideae, are a predominantly tropical group containing 35 genera and 1060 species. There are main centres of diversity in Tropical Africa and Madagascar, China and Indochina, and in South America. The group is economically and medicinally important. Basil (Ocimum) and some species of Plectranthus are widely used as pot herbs. Commercially around 100 tonnes of essential oil are produced annually from species of Ocimum and over 400 tonnes from Lavender (Lavandula). Medicinal uses include pain relief and anti-cancer properties.
Extensive herbarium, living and DNA collections at Kew were used as the basis for this project. Baseline inventory work included major revisions of the group in Africa, South East Asia and South America. Monographic work of Plectranthus was used to demonstrate the value of Herbarium collections in production of preliminary conservation assessments in collaboration with the GIS unit and 237 species conservation assessments of Ocimeae have been disseminated.
This multidisciplinary work in Ocimeae also served as a basis for investigating the distribution of flavonoids and diterpenes and the anti-insect activity of Ocimum. This focused approach allowed integration of a number of collaborative relationships involving researchers in Kenya, Ghana, Malawi, South Africa, Thailand, Denmark and the UK.
Recently, phylogenetic work in Tribe Ocimeae has concentrated on Plectranthus and a more robust phylogeny of the genus has been produced. This work was carried out in collaboration with Reading University and an updated phylogeny is currently being prepared for publication. A recent review on the ethnobotanical uses of species of Plectranthus showed that in most cases the compounds associated with their medicinal uses are not known. As part of our research into the chemistry of this genus we have been studying the flavonoids and diterpenoids in a range of species and testing the isolated compounds for anti-malarial and anti-insect activity. A review of the distribution of flavonoids has been published and a review of diterpenoids is being prepared. We also plan to publish work on the anti-insect activity of Plectranthus-derived compounds and test extracts for activity against bacteria, especially against tuberculosis.
A molecular phylogeny of tribe Ocimeae subtribe Hyptidinae is being produced in collaboration with Brazilian collaborators and has just been accepted for publication. This has resulted in major changes in generic delimitation which have also just been submitted for publication.
Project partners and collaborators
- Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Cenargen, Brasilia
- Universidade Estadual de Feira de Santana
- University of Nairobi
- University of Eldoret
- University of Witswatersrand
- University of Reading
- School of Pharmacy, University of London
- Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Brazil
- BAT/Kew Biodiversity Partnership
- University of Witwatersrand/ Andrew Mellon Foundation PhD Scholarship
- Bentham-Moxon Trust