Abstract:
Type 2 diabetes (T2D) is increasing rapidly in Africa. An appropriate therapeutic approach
is to inhibit intestinal carbohydrate digesting enzymes using plant polyphenols. A crude
preparation of sorghum condensed tannins (SCT) was highly effective (approx. 20,000 times)
at inhibiting α-glucosidase compared to acarbose, while acarbose was a better α-amylase
inhihitor (approx. 180 times). Kafirin microparticles (KEMS) were investigated as an oral delivery
system for SCT. Using a simple aqueous alcohol coacervation method, the encapulation
efficiency of SCT in the KEMS was approx. 48%. Quantitative data and electron microscopy
revealed that KEMS encapsulating SCT were digested to only a limited extent during simulated
gastrointestinal digestion with pepsin and trypsin–chymotrypsin. Hence, SCT
encapsulated in KEMS retained their inhibitory activity against both amylases, throughout
simulated gastrointestinal digestion, whereas unencapsulated SCT lost most of their inhibitory
activity.Thus, KEMS encapsulating SCT have potential as a nutraceutical to attenuate
hyperglycaemia and control T2D.
