Structure and mitogenic activities of corn cob heteroxylans

Various structurally different water-soluble (ws) and water-insoluble (wis) heteroxylans have been tested for mitogenic and co-mitogenic activity and shown to differ in their stimulating potency. The ws arabinoglucuronoxylan (ws-AGX) from corn cobs exhibited the highest potency which was comparable to that of the immunomodulator zymosan, whereas the wis-AGX from corn cobs was inactive. Water-soluble derivatives of wis-AGX as well as hydrolytically modified ws-AGX fractions were prepared and tested for their mitogenic and co-mitogenic activity. The results indicate that the disaccharide side chains present only in ws-AGX might be important for expression of the immunostimulatory activity of this xylan.