Antioxidant and Hypoglycemic Properties of Seeds of Cucurbitaceae Family from Western Nepal

Abstract

Introduction: Diabetes mellitus is an endocrine and metabolic disorder characterized by the defect in insulin secretion or insulin action or both. The association between diabetes mellitus and oxidative stress is well established. Cucurbitaceae is the largest family containing 120 genera mostly grown for its sweet and juicy fruit in warm climates all over the world. In the present work ethanolic extracts of the seeds of Trichosanthes cucumerina Linn (Chichinno), Lagenaria siceraria (Lauka), Cucurbita pepo (Pharsi), Luffa aegiptiaca (Ghiraula), and Benincasa hispida (Kubindo) collected from Western Nepal has been evaluated for their in vitro antioxidant activity and in vivo hypoglycemic effects.

Methods: In vitro antioxidant activity was assessed by using DPPH free radical scavenging activities and their IC50 values were calculated. In vivo hypoglycemic effect was examined on normoglycemic rats. The clinical significance of ethanolic extract at the doses of 250 and 500 mg/kg body weight was investigated in 0, 30, 60, 120 and 180 minutes of oral administration. Metformin treated group was used as the positive control.

Results: For DPPH radical scavenging action, the IC50 values of Trichosanthes cucumerina, Luffa aegiptiaca, Benincasa  hispida, Cucurbita pepo, Lagenaria siceraria were found to be 60.72, 127.73, 49.63, 98.16 and 52.46 µg/ml respectively which were compared to the IC50 value of ascorbic acid (Positive control) which was found to be 38.11 µg/ml. The extracts of Benincasa hispida, and were having higher antioxidant activity and tested for in vivo hypoglycemic activity.
In vivo administration of two doses of ethanolic extract of Lagenaria siceraria reduced the level of blood glucose while the best result was obtained at 250 mg/kg.

Conclusions: Present study revealed promising antioxidant and hypoglycemic activity of ethanolic extract of Lagenaria siceraria. The further exploration of Lagenaria siceraria for its effective use in the traditional medicinal system is essential.