Molecular characterization, rheological properties, and prebiotic properties of arabinoxylans from waxy and sweet corn cobs

Background and Objectives

Arabinoxylan (AX) has diverse physicochemical properties and biological activities, related to the structural differences caused by various sources and extraction methods. We study the differences in molecular characterization, rheological properties, and prebiotic properties in waxy and sweet corn cobs AX, and water-extractable and water-unextractable arabinoxylan (EAX, UAX).

Findings

The arabinose to xylose ratios (Ara/Xyl) of waxy corn cobs AX were lower than that of sweet corn cobs AX. Also, the viscosity of all samples increased with increasing concentration and decreasing temperature. In the vitro probiotic fermentation, waxy corn cobs AX was stronger in promoting the growth of probiotics than AX from sweet corn cobs. Probiotics in the AX group were predominantly acetic acid and butyric acid producers, and the waxy corn cobs AX group produced more short-chain fatty acids than the sweet corn cobs AX group, resulting in a lower pH in the waxy corn cobs AX group.

Conclusions

EAX and UAX also showed significant variations in molecular characterization, viscosity, and prebiotic properties. Waxy corn cobs AX had stronger prebiotic activity than sweet corn cobs AX.

Significance and Novelty

This experiment provides a theoretical and experimental basis for studying the prebiotic properties of AX, which could guide the application of fresh corn cobs-derived AX.