Tropical medicinal plant research in the Economic Botany Collection, Kew

By Kim Walker, PhD Student, History of Medicine, Royal Botanic Gardens, Kew and Royal Holloway.

A blog on the use of plant collections as sources of research in the history of medicine.

Figure 1: ( Heading) Cinchona bark sample from the Economic Botany Collection, RBG Kew. Credit: Harriet Gendall, RBG Kew.

Introduction

Archaeological evidence and ancient trading routes such as the Silk Road show the interest humans have always had in seeking out and trading in ‘exotic’ sources of plants as foods and medicines (Wallis, 2012; Kuzima et al., 2017). Since the 18th and 19th century, with the establishment of trade routes to the Americas, there has been a significant market for tropical food, medicines and cultivated plants to new global localities.

The Royal Botanic Gardens, Kew encapsulates 250 years of British plant collecting and has established research projects investigating the history, movement, development and conservation of some of these plant stories. A strong point of many of these research projects is the use of the collections. The herbarium has 7 million plant specimens, and the Economic Botany Collection contains 100,000 plant products, with roughly a quarter representing herbal medicines.  These medicines range from ancient Egyptian burial flowers, early modern materia medica cabinets, to objects used in drug development including modern day collections. One of the projects using the medicinal collection is the one I am involved in, investigating the history of the development of the medicinal cinchona tree (Cinchona sp.).

 

Cinchona

Figure 2: Cinchona barks from the Economic Botqany Collection, RBG Kew.

Until the 20th Century, the bark of the cinchona tree provided the only effective anti-malarial known within Europe. It was native to the Eastern Andes, an area controlled by the Spanish Empire during the 18th and 19th centuries. The only source of this medicine to Europe was at trade ports, where bark entered in bulk packages, and the quality and quantity were uncertain as demand steadily rose. Threats of over-harvesting and the desire to control the source of this precious bark drove various competing Empires to source this plant for themselves for government controlled plantations. Understandably, the Spanish Government actively tried to prevent this, but failed to establish successful cultivation themselves. A race to source cinchona seeds/plants ensued, and eventually both the Dutch, in Indonesia, and the British, in India, founded plantations for mass production of quinine, the active constituent alkaloid.  The collections at Kew reflect this 19th century endeavour across Europe to understand the complex botany and chemistry and attempts at cultivation, which was complicated by the variable chemistry of the plant. Cinchona has a complex history involving difficult stories of empire, colonisation and transplantation, and my work at Kew will hopefully uncover some of these stories.

 

19th century collections in the Amazonian territory

Another recent project at the Economic Botany Collection is in collaboration with Birkbeck University. A team of interdisciplinary researchers including botanists, ethnobotanists, academics, artists along with source communities in the Amazon are working together on the collections of the 19th century botanist Richard Spruce (1817-1893). The aim of the project is to reconnect artefacts and botanical specimens he collected from tribes in the Amazon. Participants in the current project include the Tukano, Tuyuka, Desana, Yebamasã, Baniwa, Koripaco & Pira-Tapuya indigenous communities. (Milliken & Nesbitt, 2017; Birkbeck University, 2017)

The images and data of over 300 objects have been digitised including cassava graters, sacred trumpets, ceremonial shields and medicinal plants. These objects have been used to reconnect indigenous tribes with ancestral objects, provide insights on plant species used as well as providing training in botany, photography and conservation. One output has been the ‘Manual de etnobotânica: Plantas, artefatos e conhecimentos indígenasa which has been translated into the indigenous dialects of Baniwa and Tukano, and with permission, into English and Portuguese (Fonseca-Kruel et al.,  2017).

Figure 3: Manual de Etnobotânica: Plantas, artefatos e conhecimentos indígenas.

Historic botanical collections are potential sources for a range of research subjects including history of medicine, ethnobotany, conservation of plants and the development of new drugs, respecting and exploring issues such as intellectual property and the Nagoya protocol. The internet and digital collections are important tools for reconnecting people with collections recording their history. These diverse and dispersed collections can be found across the world in botanic gardens, museums, and private collections and have fascinating stories  about the movement and use of plant medicines, ancient and modern, just waiting to be uncovered.

 

References

Birkbeck University (2017). Supporting indigenous knowledge. Blog. [online] Available at: http://www.bbk.ac.uk/news/supporting-indigenous-knowledge. Accessed 30 September 2018.

Fonseca-Kruel, V., et al., (2017). Manual de etnobotânica: Plantas, artefatos e conhecimentos indígenas. [online] Available at: https://issuu.com/instituto-socioambiental/docs/manual_de_etnobotanica_baixa. Accessed 30 September 2018

Kuzmina, E., & Mair, V., (2017). The prehistory of the Silk Road. Philadelphia, PA: University of Pennsylvania Press. http://www.upenn.edu/pennpress/book/14383.html Accessed 30 September 2018

Milliken, W., & Nesbitt, M., (2017). Mobilising Richard Spruce’s 19th century Amazon legacy. Blog [online] Available at: https://www.kew.org/blogs/kew-science/mobilising-richard-spruce%E2%80%99s-19th-century-amazon-legacy Accessed 30 September 2018

 Wallis, P., (2012). Exotic Drugs and English Medicine: England’s Drug Trade, c. 1550–c. 1800. Social History of Medicine 25, 20–46. https://doi.org/10.1093/shm/hkr055 Accessed 30 September 2018