1.
Dietary fiber polysaccharides of amaranth, buckwheat and quinoa grains: A review of chemical structure, biological functions and food uses.
Zhu, F
Carbohydrate polymers. 2020;:116819
Abstract
Seeds of amaranth (Amaranthus spp.), buckwheat (Fagopyrum esculentum and F. tataricum) and quinoa (Chenopodium quinoa) become popular foods due to their attractive health effects. Cell wall polysaccharides are the major components of dietary fiber and significantly contribute to diverse health effects of the grains. This review summarizes chemical and physical structure, biological functions and food uses of the cell wall polysaccharides and fractions as fiber components from the 3 pseudocereals. The properties and uses of the polysaccharides and fractions are compared with those of fiber polysaccharides from common sources such as fruits and vegetables. Overall, the fiber polysaccharide composition of the pseudocereals is more similar to that of fruits and vegetables than to that of cereals. The fiber polysaccharides showed a range of biological functions such as antioxidation, anticancer and immunomodulation. The fiber polysaccharides of amaranth, buckwheat and quinoa have potential to be used in formulations of functional foods.
2.
Interactions between cell wall polysaccharides and polyphenols.
Zhu, F
Critical reviews in food science and nutrition. 2018;(11):1808-1831
Abstract
In plant-based food systems such as fruits, vegetables, and cereals, cell wall polysaccharides and polyphenols co-exist and commonly interact during processing and digestion. The noncovalent interactions between cell wall polysaccharides and polyphenols may greatly influence the physicochemical and nutritional properties of foods. The affinity of cell wall polysaccharides with polyphenols depends on both endogenous and exogenous factors. The endogenous factors include the structures, compositions, and concentrations of both polysaccharides and polyphenols, and the exogenous factors are the environmental conditions such as pH, temperature, ionic strength, and the presence of other components (e.g., protein). Diverse methods used to directly characterize the interactions include NMR spectroscopy, size-exclusion chromatography, confocal microscopy, isothermal titration calorimetry, molecular dynamics simulation, and so on. The un-bound polyphenols are quantified by liquid chromatography or spectrophotometry after dialysis or centrifugation. The adsorption of polyphenols by polysaccharides is mostly driven by hydrophobic interactions and hydrogen bonding, and can be described by various isothermal models such as Langmuir and Freundlich equations. Quality attributes of various food and beverage products (e.g., wine) can be significantly affected by polysaccharide-polyphenol interactions. Nutritionally, the interactions play an important role in the digestive tract of humans for the metabolism of both polyphenols and polysaccharides.