Recently, the tobacco functional component and integrative use innovation team of the Tobacco Research Institute of Chinese Academy of Agricultural Sciences collaborated with Qingdao Agricultural University, and Guelph Food Research Centre of Agriculture of Agri-Food Canada to systematically summarize the latest progress achieved by Chinese and international scientists in research on the nutritional constituents, phytochemicals, antioxidant activities, and health-promoting effects of wild rice (Zizania spp.) plants. This study could provide a theoretical and technical basis for the mining of functional genes and the development of functional foods from Zizania plants. Relevant research findings were published online in the Journal of Food Chemistry.

According to Dr Yan Ning, the corresponding author of this study, the Zizania plants include four species: Zizania latifolia found in East Asia, and Zizania aquatica, Zizania palustris, and Zizania texana found in North America. In recent years，Zizania plants have gained attention due to their antioxidant activities and health-promoting effects. However, there are few studies that systematically compile and summarize the investigations on functional foods from Zizania plants at present.　

This study summarizes the nutritional constituents and phytochemicals present in wild rice. As a whole grain, wild rice is rich in proteins, vitamins, minerals, and phytochemicals, as well as low in fat. The phytochemicals in wild rice mainly include phytosterols, g-oryzanol, g-aminobutyric acid, phenolic acids, and flavonoids. Among these phytochemicals, phenolic compounds, such as phenolic acids and flavonoids, constitute the major antioxidants found in wild rice and are intimately associated both with in vitro and in vivo antioxidant activity. A large number of studies showed that the health-promoting effects of Zizania plants include the alleviation of insulin resistance and lipotoxicity, atherosclerosis prevention, as well as anti-inflammatory, anti-allergic, anti-hypertensive, and immunomodulatory effects. This study specifically indicated that these beneficial effects might be due to the synergistic effects of their nutritional constituents and unique phytochemicals, such as their high content of dietary fibre and phenolic compounds. Considering the current scientific literature and knowledge on the health benefits of wild rice consumption in rats or mice, further in vivo studies in humans, involving different doses of wild rice in the daily diet, are needed to confirm the health-promoting effects observed in rats and mice.

This study 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 1610232020008), 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/abs/pii/S0308814620311559

By Yan Ning (yanning@caas.cn)