Kafirin microparticle encapsulated sorghum condensed tannins exhibit potential as an anti-hyperglycaemic agent in a small animal model

• Published in: Journal of functional foods 2016-01, Vol.20, p.394-399
• Main Authors: Links, Malory R., Taylor, Janet, Kruger, Marlena C., Naidoo, Vinny, Taylor, John R.N.
• Format: Article
• Language: English
• Subjects: Encapsulation; Hyperglycaemia; Kafirin; Oral starch tolerance test; Sorghum tannins
• ISSN: 1756-4646; 2214-9414
• DOI: 10.1016/j.jff.2015.11.015

•Oral starch test performed on rats with sorghum tannins encapsulated in kafirin.•Kafirin encapsulated tannins prevented blood glucose spike.•Kafirin encapsulated tannins decreased maximum blood glucose levels.•Kafirin encapsulated tannins prevented elevated serum insulin levels.•Kafirin encapsulated tannins have nutraceutical potential for diabetes management. In vitro analysis has indicated that sorghum condensed tannins (SCT) survive simulated gastric digestion and inhibit digestive amylases when encapsulated in sorghum kafirin protein microparticles (SCT-KEMS). This study investigated SCT-KEMS as a potential anti-hyperglycaemic nutraceutical agent in vivo. Oral starch tolerance tests were performed on healthy rats. SCT-KEMS prevented a blood glucose spike and decreased the maximum blood glucose level by 11.8% compared to the water control, the same reduction as the acarbose standard. Neither SCT-KEMS nor acarbose elevated serum insulin levels. Further, the rats took the SCT-KEMS willingly, unlike the case with the unencapsulated SCTs. SCT-KEMS are potentially effective nutraceuticals for the management of hyperglycaemia because of the high affinity of SCT for the proline-rich kafirin and kafirin's slow digestibility, which enables SCT bitterness to be masked and delivered to the small intestine to inhibit carbohydrate hydrolysis, thus reducing glycaemic response.