Evaluation of pranthocyanidin enriched cranberry extract for carbohydrate hydrolysis enzyme inhibition (647.38)

Abstract

Proanthocyanidins (PACs), found in cranberries (Vaccinium macrocarpon), are hypothesized to be natural, oral hypoglycemic agents. This study investigates the inhibition potential of cranberry powder in carbohydrate hydrolysis enzymes. The whole extract (WE) was achieved by dissolving one gram of cranberry powder in 100 mL acetone solution (acetone: water: hydrochloric acid, 70:29.9:0.01) at room temperature. The sample was differentiated into two fractions: low molecular weight phenolic enriched fraction (LMWF) and PAC enriched fraction (PACF) using LH‐20. PAC contents were evaluated by 4‐Dimethylaminocinnamaldehyde (DMAC)assay and yielded 1.35, 0.03 and 0.59 mg/mL for WE, LMWF and PACF respectively. The total phenolic contents of were determined to be 4.68, 0.60, and 2.51 mg/mL for WE, LMWF and PACF respectively. Rat α glucosidase assays showed PACF has 3 times lower inhibitory activity and LMWF has almost 2 times higher inhibitory activity, compared to WE. Sucrase inhibition assays showed PACF has lower inhibitory activity and that LMWF has almost 2 times higher inhibitory activity, compared to WE. Lastly, maltase inhibition assays showed both PACF and LMWF have lower inhibitory activity compared to WE. The results suggest cranberry has an inhibitory effect against the action of alpha‐glucosidases, which is mainly due to sucrase inhibition, and is low molecular weight phenolic dependent.Grant Funding Source: This research was supported by US Army Natick Soldier Research Engineering Center