Isolation, in vitro antidiabetic, antioxidant activity and molecular docking studies of pentacyclic triterpenoids from Syzygium alternifolium (wt.) Walp bark

Diabetes mellitus type 2 is a metabolic disorder characterized by hyperglycemia including insulin resistance and relative lack of insulin. Type 2 diabetes is expected to reduce ten-year-shorter life expectancy. In this research article, we have isolated two terpenoids from the stem bark of Syzygium alternifoliumby column chromatography.The isolated compounds were identified as friedelin and 3β-friedelinol terpenoids by 1H-NMR, 13C-NMR, and Mass spectroscopy. Isolated compounds were screened for in vitro enzyme inhibition assays against α-glucosidase & α-amylase; and were found decrease plasma glucose level significantly showing antidiabetic activity. Isolated compounds also exhibited significant radical scavenging antioxidant activity by DPPH inhibition assay. The results of in vitro experimentation were confirmed by the molecular docking studies of the isolated terpenoids on α-glucosidase and α-amylase enzymes.The present researchreveals the antidiabetic and antioxidant activity of isolated terpenoids from stem bark of Syzygium alternifolium against diabetes mellitus type 2 disorders.