Wheat grain phenolics: a review on composition, bioactivity, and influencing factors

Abstract

Wheat (Triticum aestivum L.) is a widely cultivated crop and one of the most commonly consumed food grains in the world. It possesses several nutritional elements. Increasing attention to wheat grain phenolics bioactivity is due to the increasing demand for foods with natural antioxidants. To provide a comprehensive understanding of phenolics in wheat grain, this review first summarizes the phenolics' form and distribution and the phenolic components identified in wheat grain. In particular, the biosynthesis path for phenolics is discussed, identifying some candidate genes involved in the biosynthesis of phenolic acids and flavonoids. After discussing the methods for determining antioxidant activity, the effect of genotypes, environmental conditions, and cultivation systems on grain phenolic component content are explored. Finally, the bioavailability of phenolics under different food processing method are reported and discussed. Future research is recommended to increase wheat grain phenolic content by genetic engineering, and to improve its bioavailability through proper food processing.

Dynamic Metabolomics and Transcriptomics Analyses for Characterization of Phenolic Compounds and Their Biosynthetic Characteristics in Wheat Grain

“…Widely targeted metabolome enables the identification of more phenolic compounds, but the detected metabolites are relatively quantitative. It is widely accepted that the antioxidant activities of phenolic compounds were significantly different ( 10 , 43 ). Exploring the substances with high bioactive components in HP512 and verifying their activity in vivo need to be done.…”

“…Orientin and isoorientin were significantly and highly overexpressed in immature grains (30 DAA), indicating that HPm512 can be used for the production of food rich in bioactive substances even in immature grains. It is widely known that planting environment has a significant effect on grain phenolics content ( 10 ). We have to mention that although total phenolics content of HPm512 varied in different planting conditions, its relative abundance was significantly higher than that of control ZM22, which confirmed that HPm512 has potential health benefits.…”

“…Phenolic acids and flavonoids are the major phenolic compounds in wheat grains (10). The phenolic compounds identified in wheat grains include hydroxybenzoic acids (gallic, protocatechuic, and syringic acids) and hydroxycinnamic acids (ferulic, caffeic, chlorogenic, sinapic, and p-coumaric acids) (10). Generally, ferulic acid is the most abundant bound phenolic acid compound accounting for 65.0% of total phenolic acid content (11)(12)(13).…”

“…According to previous studies, daily consumption of whole wheat grains can provide health benefits and reduce the risk of certain diseases ( 8 , 9 ). Phenolic acids and flavonoids are the major phenolic compounds in wheat grains ( 10 ). The phenolic compounds identified in wheat grains include hydroxybenzoic acids (gallic, protocatechuic, and syringic acids) and hydroxycinnamic acids (ferulic, caffeic, chlorogenic, sinapic, and p -coumaric acids) ( 10 ).…”

“…Additionally, a few wheat mutant cultivars with higher flavonoids or cell-bound phenolics were isolated from a wheat ethyl methanesulfonate mutant library ( 19 ). Apart from genotypes, environmental factors, such as soil fertilization, rainfall, and temperature, significantly affect the phenolic content of wheat grains ( 10 ). The phenolic content and components in wheat grain are different during the grain filling stage.…”