Seasonal variation of nutritional and bioactive constituents in Polygonatum odoratum

Abstract

Changes in the main nutrients and functional components during the growth and development of Polygonatum odoratum rhizome (POR) in the third year after planting were investigated. Carbohydrates and crude proteins were the two main components in POR and their contents were negatively associated. From spring to autumn, the carbohydrate content decreased first and then increased, with the lowest content (69.1%) in the tender POR harvested in summer and the highest content (84.8%) in the tender POR harvested in autumn, while the crude protein content exhibited an opposite trend, with the lowest content (5.4%) in the senescent POR harvested in autumn and the highest content (18.2%) in the tender POR harvested in summer. POR harvested in summer was rich in soluble sugar and free amino acids with better taste, which makes it suitable for common food development, while POR harvested in autumn was high in polysaccharides and saponins, which makes it suitable for medicinal use. This study provides some data for the classified processing and harvesting of POR. In the future, it is necessary to further study the relationship between fertilization management and composition change of this medicine food homology plant.