The U.S. food and non-food industries would bene t from domestically produced crude, semi-pure and pure bio-based ber gums from corn bran and oat hulls. Corn bran and oat hulls are processed to produce commercial cellulose enriched ber gels, which generate an alkaline waste stream containing many valuable and functional components, including bio-based ber gums. In this study, the corn bran and oat hulls processing waste streams were concentrated and drum or spray dried to produce solid products, called crude bio-based ber gum (crude BFG). Alternatively semi-pure products (semi-pure BFG) were prepared by ethanol precipitation of the concentrated waste stream. Semi-pure product was also pro- duced by puri cation of the original unconcentrated waste stream using 10, 50 and 100 kDa MWCO ultra ltration membranes. A highly pure BFG was prepared from the unconcentrated waste stream by rst adjusting its pH to 4, removing the precipitated material and precipitating the resulting supernatant with two times its volume with ethanol. All four kinds of BFGs contain arabinoxylan but with different levels of purity. The arabinoxylans have a typical structure with a slight variation in Ara/Xyl ratio showing some differences in their branching. There is a big variation in their weight average molar mass (Mw) (33 e386 kDa) due to variation in the processing conditions of the waste streams. Arabinoxylans are good emulsi ers for oil-in-water emulsion systems and binding agents for petroleum coke pellets and bri- quettes. They are also useful antioxidants and soluble dietary bers with antioxidant activities showing a great potential for their applications in both food and non-food industries.