Target guided isolation, in-vitro antidiabetic, antioxidant activity and molecular docking studies of some flavonoids from Albizzia Lebbeck Benth. bark

Background: Albizzia Lebbeck Benth. is traditionally important plant and is reported to possess a variety of pharmacological actions. The present research exertion was undertaken to isolate and characterized the flavonoids from the extract of stem bark of Albizzia Lebbeck Benth. and to evaluate the efficacy of the isolated flavonoids on in-vitro models of type-II diabetes. Furthermore, the results of in-vitro experimentation inveterate by the molecular docking studies of the isolated flavonoids on alpha-glucosidase and alpha-amylase enzymes. Methods: Isolation of the flavonoids from the methanolic extract of stem bark of A. Lebbeck Benth was executed by the Silica gel (Si) column chromatography to yield different fractions. These fractions were then subjected to purification to obtain three important flavonoids. The isolated flavonoids were then structurally elucidated with the assist of H-1-NMR, C-13-NMR, and Mass spectroscopy. In-vitro experimentation was performed with evaluation of alpha-glucosidase, alpha-amylase and DPPH inhibition capacity. Molecular docking study was performed with GLIDE docking software. Results: Three flavonoids, (1) 5-deoxyflavone (geraldone), (2) luteolin and (3) Isookanin were isolated from the EtOAc fraction of the methanolic extract of Albizzia lebbeck Benth bark. (ALD). All the compounds revealed to inhibit the alpha-glucosidase and alpha-amylase enzymes in in-vitro investigation correlating to reduce the plasma glucose level. Molecular docking study radically corroborates the binding affinity and inhibition of alpha-glucosidase and alpha-amylase enzymes. Conclusion: The present research exertion demonstrates the anti-diabetic and antioxidant activity of the important isolated flavonoids with inhibition of alpha-glucosidase, alpha-amylase and DPPH which is further supported by molecular docking analysis.