Antidiabetic properties of finger millet (Eleusine coracana (L.) Gaertn.) varieties cultivated in Sri Lanka

Abstract

IntroductionFinger millet is considered as a therapeutic food for diabetes mellitus. However, there is a lack of scientific evidence on the antidiabetic potential of the finger millet varieties which are commonly cultivated in Sri Lanka. Materials and methodsThis study was focused on determining anti-α-amylase, anti-α-glucosidase, antiglycation, glycation reversing and radical scavenging activities and total phenolic and flavonoid contents of Ravi, Rawana and Oshadha finger millet varieties, using ethanolic and methanolic extracts of whole grain flours, in view of their antidiabetic potential. Results and discussionThe findings revealed anti-α-amylase, anti-α-glucosidase, antiglycation and glycation reversing activities of Ravi, Rawana and Oshadha finger millet varieties while indicating their potential of decreasing the postprandial hyperglycemia and preventing advanced glycation end products-mediated diabetic complications. Ethanolic extract of Oshadha indicated the highest anti-α-amylase activity (IC50 value: 1.62 ± 0.04 mg/mL), methanolic extract of Oshadha indicated the highest antiglycation (IC50 value: 79.42 ± 4.46 µg/mL) and glycation reversing (EC50 value: 411.76 ± 5.91 µg/mL) activities and methanolic extract of Ravi indicated the highest anti-α-glucosidase activity (IC50 value: 47.96 ± 0.79 µg/mL). Anti-α-amylase and anti-α-glucosidase activities of the finger millet varieties can be attributed to their phenolic and flavonoids contents and antiglycation and glycation reversing activities can be attributed to the radical scavenging potential of their phenolic compounds including flavonoids. ConclusionThese findings scientifically proved the efficacy of using Ravi, Rawana and Oshadha varieties in prevention and dietary management of diabetes mellitus and its complications and reinforced the traditional recommendation of finger millet-based foods for diabetic patients.