Yu Bianyun, Patterson Nii, Zaharia L Irina
Aquatic and Crop Resource Development Research Center, National Research Council Canada, Saskatoon, SK S7N 0W9, Canada.
Plants (Basel). 2022 Dec 14;11(24):3505. doi: 10.3390/plants11243505.
Pulses are a group of leguminous crops that are harvested solely for their dry seeds. As the demand for plant-based proteins grows, pulses are becoming important food crops worldwide. In addition to being a rich source of nutrients, pulses also contain saponins that are traditionally considered anti-nutrients, and impart bitterness and astringency. Saponins are plant secondary metabolites with great structural and functional diversity. Given their diverse functional properties and biological activities, both undesirable and beneficial, saponins have received growing attention. It can be expected that redirecting metabolic fluxes to control the saponin levels and produce desired saponins would be an effective approach to improve the nutritional and sensory quality of the pulses. However, little effort has been made toward understanding saponin biosynthesis in pulses, and, thus there exist sizable knowledge gaps regarding its pathway and regulatory network. In this paper, we summarize the research progress made on saponin biosynthesis in pulses. Additionally, phylogenetic relationships of putative biosynthetic enzymes among multiple pulse species provide a glimpse of the evolutionary routes and functional diversification of saponin biosynthetic enzymes. The review will help us to advance our understanding of saponin biosynthesis and aid in the development of molecular and biotechnological tools for the systematic optimization of metabolic fluxes, in order to produce the desired saponins in pulses.
豆类是一类豆科作物,仅收获其干燥种子。随着对植物蛋白需求的增长,豆类正成为全球重要的粮食作物。除了是丰富的营养来源外,豆类还含有传统上被认为是抗营养物质的皂苷,并带有苦味和涩味。皂苷是具有高度结构和功能多样性的植物次生代谢产物。鉴于其多样的功能特性和生物活性,既有不良的也有有益的,皂苷受到了越来越多的关注。可以预期,重新引导代谢通量以控制皂苷水平并产生所需的皂苷将是提高豆类营养和感官品质的有效方法。然而,在理解豆类中皂苷生物合成方面所做的努力很少,因此在其途径和调控网络方面存在相当大的知识空白。在本文中,我们总结了豆类中皂苷生物合成的研究进展。此外,多个豆类物种中假定生物合成酶的系统发育关系揭示了皂苷生物合成酶的进化路线和功能多样化。这篇综述将有助于我们加深对皂苷生物合成的理解,并有助于开发分子和生物技术工具,以系统地优化代谢通量,从而在豆类中产生所需的皂苷。