The influences of acetylation, hydroxypropylation, enzymatic hydrolysis and crosslinking on improved adsorption capacities and in vitro hypoglycemic properties of millet bran dietary fibre

The effects of acetylation, hydroxypropylation, cellulase hydrolysis and crosslinking on adsorption capacities and in vitro hypoglycemic activities of millet bran dietary fibre (MBDF) were studied. The results demonstrated that both acetylation and hydroxypropylation improved water swelling ability of MBDF, and adsorption capacities of cholesterol, cholate and copper ion on MBDF. Acetylation and hydroxypropylation also enhanced alpha-glucosidase and alpha-amylase inhibition activities, glucose-binding ability and glucose diffusion retardation index (GDRI) of MBDF. Acetylated MBDF showed the highest cholate (77.31 mg/g) and cholesterol (13.97 mg/g) adsorption capacities. The crosslinking improved adsorption of cholate, cholesterol, copper ion (25.64 mg/g) and nitrite ion (181.59 mu g/g) on MBDF; but reduced alpha-amylase inhibition activity (p < 0.05). Moreover, cellulase hydrolyzed MBDF exhibited the highest GDRI (39.60%) and alpha-amylase inhibition activity (34.53%), but the lowest oil and cholate adsorption capacities. The results suggest that the modified MBDFs can be used as an ingredient of hypoglycemic foods.

Automated summary

The study found that acetylation and hydroxypropylation can enhance the water swelling ability and adsorption capacities of MBDF, as well as improve its hypoglycemic activities. Crosslinking improved the adsorption capacities of certain substances but reduced enzyme inhibition activity to some extent.