3rd Edition Of Plant Science and Molecular Biology World Conference 2026

Abstract

Chenopodium quinoa is a nutritionally rich and climate-resilient pseudocereal gaining attention globally. Quinoa seeds are gluten-free and rich in protein and micronutrients. However, they taste bitter due to the presence of antinutritional oleanane-type triterpenoid saponins viz. oleanolic acid, hederagenin and ursolic acid. Oleanolic acid sapogenin is the major saponin found in C. quinoa seeds. Oleanolic acid-containing saponins are bitter and hemolytic. Oleanolic acid is synthesized by the cyclization of 2,3-oxidosqualene by beta-amyrin synthase followed by the oxidation of beta-amyrin. Oxidation of beta-amyrin is catalyzed by the action of cytochrome 450 enzymes. Plant genomes contain cytochrome P450 (CYP) supergene family involved in the biosynthesis of sapogenin aglycones. Here, by performing homology-based sequence analysis we identified a CYP716A in C. quinoa, which converts beta-amyrin into oleanolic acid. The functional validation was carried out by homologous transient overexpression and virus-induced gene silencing (VIGS) of CYP716A through agro-infiltration in the leaves of C. quinoa, followed by UPLC-MS quantification of the metabolites. Furthermore, heterologous expression in tobacco and Arabidopsis demonstrated the biological functionality of CYP716A in growth and stress responses. In summary, we discovered a novel beta-amyrin 28-oxidase enzyme (CYP716A) that catalyzes the biosynthesis of oleanolic acid in C. quinoa and explored its role in growth and defense. These results provide a strong foundation for understanding triterpenoid saponin biosynthesis in C. quinoa and designing saponin-free varieties.