In another example of nature beating chemists, the African plant Nauclea latifolia has been found to be a natural source of the synthetic opioid tramadol. First marketed in 1977, tramadol is frequently used to relieve moderate to moderately-severe pain. While other synthetic drugs have later been found in nature, this is the first instance where the discovery involves clinically viable concentrations.

Colloquially known as the ‘African peach’ or ‘pin cushion tree’, N. latifolia is a flowering, sub-Saharan evergreen that grows widely across Central and West Africa and is used by local populations to treat a wide variety of ailments – including epilepsy, malaria, general pain and many infectious diseases.

To uncover the source of the plant’s reported pain killing effect, the researchers fractioned methanolic extracts of the plant by high performance liquid chromatography (HPLC). The resulting fractions were then tested in an assay using live mice, revealing the fraction with the greatest analgesic properties.

‘Our results indicate that high amounts of the analgesic drug, tramadol, can be obtained through a simple extraction procedure from Nauclea latifolia found in Cameroon or sub-Saharan areas,’ says Michel De Waard, a neuroscientist at the Université Joseph Fourier. De Waard adds that the root of the plant could be viably used as a source of tramadol because of the significantly high concentrations of the drug – over 1% of the original dry content.