Press releases – 2022

Leafy vegetables accompany many West African dishes, such as pounded yam in the south of the region. In collaboration with chemists from the University of Bristol, researchers from Goethe University have now successfully shown that the origins of such dishes date back 3,500 years.

FRANKFURT. Over 450 prehistoric pots were examined, 66 of them contained traces of lipids, that is, substances insoluble in water. On behalf of the Nok research team at Goethe University, chemists from the University of Bristol extracted lipid profiles, with the aim of revealing which plants had been used. The results have now been published in “Archaeological and Anthropological Sciences": over a third of the 66 lipid profiles displayed very distinctive and complex distributions – indicating that different plant species and parts had been processed.

Today, leafy vegetables, for example the cooked leaves of trees such as the baobab (Adansonia digitata) or of the shrubby – nomen est omen – bitter leaf (Vernonia amygdalina), accompany many West African dishes. These leafy sauces are enhanced with spices and vegetables as well as fish or meat, and complement the starchy staples of the main dish, such as pounded yam in the southern part of West Africa or thick porridge made from pearl millet in the drier savannahs in the north. By combining their expertise, archaeology and archaeobotany researchers at Goethe University and chemical scientists from the University of Bristol have corroborated that the origins of such West African dishes date back 3,500 years.

The studies are part of a project funded by the German Research Foundation, which was headed by Professor Peter Breunig and Professor Katharina Neumann and ended in December 2021. For over twelve years, archaeologists and archaeobotanists from Goethe University studied the Nok culture of Central Nigeria, which is known for its large terracotta figures and early iron production in West Africa in the first millennium BC – although the roots of the Nok culture in fact stretch back to the middle of the second millennium. Research focused above all on the social context in which the sculptures were created, that is, including eating habits and economy. Using carbonised plant remains from Central Nigeria, it was possible to prove that the Nok people grew pearl millet. But whether they also used starchy plants, such as yam, and which dishes they prepared from the pearl millet had so far been a mystery.

“Carbonised plant remains such as seeds and nutshells preserved in archaeological sediments reflect only part of what people ate back then," explains Professor Katharina Neumann. They hoped, she says, that the chemical analyses would deliver additional insights into food preparation. And indeed, with the help of lipid biomarkers and analyses of stable isotopes, the researchers from Bristol were able to show, by examining over 450 prehistoric pots, that the Nok people included different plant species in their diet.

Dr Julie Dunne from the University of Bristol's Organic Geochemistry Unit says: “These unusual and highly complex plant lipid profiles are the most varied seen (globally) in archaeological pottery to date." There appear to be at least seven different lipid profiles in the vessels, which clearly indicates the processing of various plant species and plant organs in these vessels, possibly including underground storage organs (tubers) such as yam.

Since the beginning of the project, the archaeobotanists have sought evidence for the early use of yam. After all, the Nok region is situated in the “yam belt" of West Africa, that is, the area of the continent in which yam is nowadays grown. Carbonised remains are of no further help here because the soft flesh of the tubers is often poorly preserved and mostly non-specific as well. The chemical analyses indicate that – apart from leaves and other as yet unidentified vegetables – the Nok people also cooked plant tissue containing suberin. This substance is found in the periderm of both overground and underground plant organs – possibly a first indication that yam was used, if not the unequivocal proof hoped for.

Through the archaeobotanical study of carbonised remains, pearl millet (Cenchrus americanus) and cowpea (Vigna unguiculata), the oily fruits of the African elemi (Canarium schweinfurthii) and a fruit known as African peach (Nauclea latifolia), which due to its high number of seeds is reminiscent of a large fig, were already known. Molecular analysis now rounds off the picture of food preparation at the sites of the Nok culture. Archaeobotanist Dr Alexa Höhn from Goethe University explains: “The visible and invisible remains of food preparation in the archaeological sediment and the pottery give us a much more complete picture of past eating habits. This new evidence suggests a significant time depth in West African cuisine."

Publication: Julie Dunne, Alexa Höhn, Katharina Neumann, Gabriele Franke, Peter Breunig, Louis Champion, Toby Gillard, Caitlin Walton‑Doyle, Richard P. Evershed Making the invisible visible: tracing the origins of plants in West African cuisine through archaeobotanical and organic residue analysis. Archaeological and Anthropological Sciences https://doi.org/10.1007/s12520-021-01476-0

Picture download: https://www.uni-frankfurt.de/111577824

Caption: Excavation of a Nok vessel at the Ifana 3 site. (Photo: Peter Breunig)

Further information
Dr Alexa Höhn
African Archaeology and Archaeobotany
Telephone +49 (0)69-798-32089
Email a.hoehn@em.uni-frankfurt.de  

Editor: Dr. Anke Sauter, Science Editor, PR & Communication Department, Tel.: +49 69 798-13066, Fax +49 69 798-763-12531, sauter@pvw.uni-frankfurt.de  

Instruct-ERIC has appointed Professor Harald Schwalbe as its new Director, succeeding Professor Sir David Stuart in the role.

OXFORD/FRANKFURT. Integrated structural biology has demonstrated its innovative power in a breath-taking manner in recent years, notably with impressive technological advances. As a European distributed research infrastructure, Instruct-ERIC has been at the forefront of this technological innovation, with centres across the continent providing access to advanced structural biology equipment and techniques.

The COVID-19 pandemic made it increasingly clear that coordinated research is required to utilise the power of structural biology to structurally understand the impact of new mutations in variants of concern. Such coordinated research has been conducted within Instruct-ERIC centres, providing a huge boost for vaccine development and drug discovery.

It is at this transition period that Prof. Harald Schwalbe from Goethe-University Frankfurt becomes the new Instruct-ERIC director as successor of Prof. David Stuart from Oxford University and Diamond Light Source. 

David Stuart commented: “Instruct has been at the forefront of the transition of structural biology into a field that routinely provides deep insights from atomic structure to cellular function and disease. It has been a real privilege to have been involved in setting up the infrastructure and working with leading scientists across Europe and the fantastic staff at the Oxford hub, to realise a vision that, although now widely accepted, seemed far-fetched when it was laid out over ten years ago. The next ten years will see fundamental change across the experimental modalities with increasing integration of experiment with computation as AI and deep learning develop more predictive power to help make sense of the avalanche of experimental data. I look forward to seeing Harald lead Instruct as it responds to the exciting challenges and opportunities."

Harald Schwalbe: "It will be key to strengthen European research in Structural Biology. In NMR spectroscopy, new 1.2 GHz machines are available, pushing the boundaries for solid-state and liquid-state NMR spectroscopy. Technology advances for cryo-EM single particle and tomography analyses are impressive."

“The initiatives in structural biology have an impact not just on a continental scale, but also at a global level. Access needs to be provided to maximise the research impact. Given the pandemic - but also the requirements from global societal challenges - it will be important to link global research endeavours for the benefit of fundamental and applied research, and for fast reactions to immediate threats and challenges."

“I am taking over from Dave Stuart with huge gratitude. He has paved the way for coordinated European research in structural biology."

Professor Harald Schwalbe's career so far has led to him being well known both for development of NMR methods and pulse sequences, and their application to very challenging questions in Chemistry and Biology. His NMR contributions thus have tremendous impact to understand biological processes. 

Instruct-ERIC is a pan-European distributed research infrastructure making high-end technologies and methods in structural biology available to users. ERIC stands for European Research Infrastructure Consortium, and refers to a specific legal form that facilitates the establishment and operation of Research Infrastructures with European interest, on a not-for-profit basis. ERICs are funded by subscription from member countries and governed by member country representatives. Instruct-ERIC is comprised of 15 Member Countries: Belgium, Czech Republic, EMBL, Finland, France, Israel, Italy, Latvia, Lithuania, Netherlands, Portugal, Slovakia, Spain and United Kingdom, and one Observer Country: Greece. Through its specialist research centres in Europe, Instruct-ERIC offers funded research visits, training, internships and R&D awards. By promoting integrative methods, Instruct-ERIC enables excellent science and technological development for the benefit of all life scientists. More on https://instruct-eric.org/

Picture download:
https://www.uni-frankfurt.de/111177368

Caption: Prof. Dr. Harald Schwalbe, Goethe University Frankfurt (Photo: Jürgen Lecher, Goethe University)

Further Information:
Prof. Dr. Harald Schwalbe
Institute for Organic Chemistry and Chemical Biology
Center for Biomolecular Magnetic Resonance (BMRZ)
Goethe University Frankfurt
Phone: +49 69 798-29737
schwalbe@nmr.uni-frankfurt.de
http://schwalbe.org.chemie.uni-frankfurt.de/