Lipidomic and metabolomic profiles of Coffea canephora L. beans cultivated in South-western Nigeria

Abstract

Coffee (Coffea spp.) is one of the most popular refreshments globally. Coffee lipid diversity has untapped potential for improving coffee marketability because lipids contribute significantly to both the health benefits and cup quality of coffee. However, there have not been extensive studies of lipids of C. canephora genotypes. In this study, Ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) profiling of lipid molecules was performed for 30 genotypes consisting of 15 cultivated and 15 conserved genotypes of C. canephora in Southwestern Nigeria. We identified nine classes of lipids in the 30 genotypes which belong to the Niaouli, Kouillou and Java Robusta group: among these, the most abundant lipid class was the triacylglycerols, followed by the fatty acyls group. Although Niaouli diverged from the Kouillou and Java Robusta genotypes when their lipid profiles were compared, there was greater similarity in their lipid composition by multivariate analysis, compared to that observed when their primary metabolites and especially their secondary metabolite profiles were examined. However, distinctions could be made among genotypes. Members of the fatty acyls group had the greatest power to discriminate among genotypes, however, lipids that were low in abundance e.g. a cholesterol ester (20:3), and phosphotidylethanolamine (34:0) were also helpful to understand the relationships among C. canephora genotypes. The lipid diversity identified among the C. canephora genotypes examined correlated with their overall Single Nucleotide Polymorphism diversity assessed by genotype-by-sequencing, supporting the relevance of this study to coffee cup quality improvement.