A process for converting a sugar from a hemicellulose-containing material into the form of a compound having at least one ionic binding site, which is characterized in that the hemicellulose-containing material is hydrolyzed enzymatically or non-enzymatically and the obtained hydrolysate is subjected to a conversion involving at least one enzymatic step, wherein sugars are released and the released sugars are converted into compounds having at least one ionic binding site, and the use of such a process.