Recently, the tobacco functional components and comprehensive utilization innovation team of the Tobacco Research Institute of the Chinese Academy of Agricultural Sciences has systematically studied the accumulation rule of bioactive components in the germinating Chinese wild rice (Zizania latifolia), and revealed the biochemical mechanism involved in antioxidant activity and phenolic profile changes during Chinese wild rice germination. It created a theoretical foundation for the research and development of functional factors and functional foods for Chinese wild rice. The related research results were published in the journal of Food Chemistry.

According to Dr. Yan Ning, the co-corresponding author of this paper, Chinese wild rice seeds are considered a health-promoting food because they are rich in various bioactive compounds, including vitamins, minerals, phytosterols, g-oryzanol, and phenolic compounds. Chinese wild rice has antioxidant activity and various health benefits, such as alleviation of insulin resistance and lipotoxicity, as well as anti-atherogenic effects. Moreover, germination can increase the content of many bioactive substances in grain seeds and play its potential health benefits. Through our previous research, it was found that the content of free, bound and total phenolics declined first and then increased during Chinese wild rice germination. However, there is still lack of information on the dynamic changes in antioxidant activities, metabolites, phenolic acids, flavonoids, and phenolic biosynthetic genes in germinating Chinese wild rice.

In the latest research, we found DPPH radical and ABTS^•+ radical cation scavenging activities of free, bound, and total phenolics initially declined and then increased during Chinese wild rice germination. Moreover, the variation in the content of p-hydroxybenzoic acid, p-hydroxybenzaldehyde, p-coumaric acid, vanillin, vanillic acid, ferulic acid, sinapic acid, epigallocatechin, and rutin was the main contributor to the antioxidant activity change during Chinese wild rice germination. The up-regulation of phenolic biosynthetic genes promoted the accumulation of phenolics in germinating Chinese wild rice. Moreover, the changes of phenolic biosynthesis enzyme activities (PAL, CHS, and CHI) were related to the changes of antioxidant activities during Chinese wild rice germination.

This work was supported by the Agricultural Science and Technology Innovation Program (Grant No. ASTIP-TRIC05), the Central Public-interest Scientific Institution Basal Research Fund (Grant No. 1610232018003 and 1610232019006), and the Science Foundation for Young Scholars of the Tobacco Research Institute of the Chinese Academy of Agricultural Sciences (Grant No. 2018A01).

More details are available in the link below:

https://www.sciencedirect.com/science/article/pii/S0308814620303459

Fig. 1. Differential metabolites in Chinese wild rice between the 36-h germination (G36) and 120-h germination (G120) stages

By Yan Ning (yanning@caas.cn)