Peredaman Radikal Bebas DPPH dan Aktivitas Inhibisi α-Glukosidase oleh Ekstrak Air Jahe Merah

Abstract

Red ginger (Zingiber officinale Roxb. var. Rubrum) contains phenolic compounds that have potential to reduce blood glucose levels (antihyperglycemic) in patients with diabetes mellitus. This study aimed to determine the inhibitory activity toward α-glucosidase, antioxidant activity in reducing DPPH free radicals, and total phenolic content of aqueous extract of red ginger. The red ginger was extracted using water solvent at 100 ^oC for 15 minutes. Analysis of antioxidant activity, inhibitory activity of α-glucosidase, and total phenolic content using the spectrofotometry. Antioxidant activity showed that the extracts from the first, second and third replicates were not significantly different (p<0.05). α-glucosidase inhibition activity showed that the 1st replicate extract had the highest value of 97.729% and was significantly different (p<0.05) from the 2nd and 3rd replicate extracts and acarbose. The total phenolic content showed that the 2nd replicate extract had the highest value, namely 27,624 mg GAE/g extract and was significantly different (p<0.05) from the 1st and 3rd replicate extracts. The 1st, 2nd, and 3rd replicates of red ginger aqueous extract has the same antioxidant activity and equivalent glucosidase inhibitory activity as acarbose.