The present paper was attempted to examine the effect of awater-soluble dietary fiber (SDF) extracted from OpuntiaStreptacantha (OpS) on postprandial blood glucose level. A OpS-SDFwas extracted from the hot-dried OpS powder. An elevation of thepostprandial blood glucose level in GK rats (a Type II diabetesmodel animal) given 0.2, 1 or 2% OpS-SDF solution orally togetherwith 20% glucose solution was significantly suppressed as comparedwith that observed in the control rats given only glucose solution.The diffusion rate of glucose and the permeation rate of glucose inthe cultured CAC0-2 cells were significantly reduced by theaddition of OpS-SDF as compared to the control. Further, in theexamination on the physico-chemical characteristics of OpS-SDF, weobtained that the glucose diffusion inhibition rates of the 0.2 or0.5% OpS-SDF solution was markedly high compared with that of purewater. The viscosity of 2% OpS-SDF solution was found to be about3,000 times high compared with that of pure water. It was revealedthat OpS-SDF in OpS is a kind of mucilaginous SDF and has thesignificant suppressing effect for elevation of postprandial bloodglucose level.

Key words: cactus, soluble dietary fiber, postprandial bloodglucose, rat(s), CAC0-2 cell,