Abstract

ABSTRACT: Beetroot (Beta vulgaris) is a root tuber belonging to the Amaranthaceae family, which has recently become popular in Nigeria. The reddish purplish tuber and green leaves are usually eaten by boiling, roasting and the raw tuber can be made into juice. Beetroot juice is a good source of bioactive compounds like polyphenols, flavonoids and anthocyanins with high antioxidant properties. This study was carried out to investigate the invitro ability of aqueous freeze-dried beetroot juice to inhibit key enzymes (α-amylase and α-glucosidase) linked to type 2 diabetes (T2D) by spectrophotometric methods. The percentage inhibition and its half maximal inhibitory concentration (IC50) of α-amylase and α-glucosidase by beetroot juice with starch revealed that; Beetroot juice inhibited α-amylase (26%-73%; IC50 = 1.78 ± 0.13 mg/mL) and α-glucosidase (53%-85%; IC50 = 0.77 ± 0.14 mg/mL) in a dose dependent manner. This was compared with the positive control acarbose which inhibits α-amylase (IC50 = 0.18 ± 0.02 mg/mL) and α-glucosidase (IC50 = 0.22 ± 0.01 mg/mL). Beetroot juice may possess hypoglycemic effects and through these inhibitory mechanisms, it could be used as an adjuvant in the management of hyperglycemia and diabetes.

Key words: Beetroot juice, carbohydrate hydrolyzing enzymes, α-amylase, α-glucosidase