Characterization of the biosynthesis of saponins during seed development in peas (Pisum sativum)
Résumé
The use of pulses as ingredients for the production of food products rich in plant proteins is increasing. However, protein fractions prepared from pea or other pulses contain significant amounts of saponins, glycosylated triterpenes which can impart a bitter taste to the final food product. Bitter flavours are currently either removed by energy-requiring physico-chemical treatments or masked by additives. We are in the process of identifying and characterizing the genes involved in saponin biosynthesis during pea seed development, with the objective of identifying mutants in which seed saponins no longer accumulate. To do this we have applied a saponin extraction protocol to follow the biosynthesis of these compounds during the development of pea seeds, and have identified mutants in a Pea TILLING population (1) that correspond to key steps in the saponin biosynthetic pathway. A mutation in a previously identified β-Amyrin Synthase gene (2), which is highly expressed in maturing pea seeds, reduced mature seed saponin content by 97% (3). Acknowledgement: This study is funded under the LEG'UP FUI (Unique Interministerial Fund) project (AAP No. 18)