Grafted ferulic acid dose-dependently enhanced the apparent viscosity and antioxidant activities of arabinoxylan

Ferulic acid (FA) of various ratios was successfully tagged onto arabinoxylan (AX) molecule by N,N'carbon-yldiimidazole (CDI) radical grafting reaction. The structural characterization of conjugates was conducted using methylation analysis, UV-vis, FT-IR and H-1 NMR spectroscopy. The linkage patterns of AX before and after conjugation were similar. However, tagging FA onto AX significantly decreased the water solubility & Mw, whereas the apparent viscosity & antioxidant activity of AX were significantly enhanced. All these changes were positively correlated with the degree of attached FA. This study showed that trace amounts of phenolic com-pounds play a critical role in affecting the functional and bioactive properties of non-starch polysaccharides, which pave the way to develop novel dietary fibres with targeted functional and/or physiological properties.

Automated summary

Ferulic acid was successfully tagged onto arabinoxylan molecule by CDI radical grafting reaction, which resulted in decreased water solubility and molecular weight of AX, but increased apparent viscosity and antioxidant activity. These changes were positively correlated with the degree of attached FA. The study highlights the critical role of phenolic compounds in affecting the functional and bioactive properties of non-starch polysaccharides.