Phytochemical Analysis, Pharmacological Activities, Isolation and Characterization of Bioactive Compounds From the Roots of Sterculia urens Roxb.

Abstract

The present study is intended to explore the pharmacological significance of the crude root extract of Sterculia urens Roxb. Further the bio-active compounds were isolated and characterized using chromatographic and spectroscopic techniques. Soxhlet extraction apparatus was utilised for isolating the chemical constituents from the root extract using a series of solvents such as n-hexane, ethyl acetate (EA), methanol (ME) and water (WA). The pharmacological activities such as inhibition of DPPH radical activity, α-amylase enzyme activity, albumin denaturation along with anti-bacterial and thrombolytic activities. The isolation of purified bio-active constituents was carried using preparative HPLC technique and the purified compounds were characterized using spectroscopic techniques like NMR and Mass spectroscopy. Among the crude root extracts, methanolic extract shows high DPPH radical scavenging activity with IC₅₀ concentration of 26.74±0.08 µg/mL. The IC₅₀ concentrations in α-amylase enzyme inhibition activity was 263.96±0.90, 127.73±1.23 and 223.54±4.76 µg/mL for EA, ME, WA extracts respectively. The ME extract shows high albumin denaturation inhibition assay than other extracts with IC₅₀ concentration as 137.09±0.20 µg/mL which is very close to standard ascorbic acid. The ME shows high % clot lysis than other extracts and results were comparable with 100 μL of streptokinase standard. The preparative HPLC followed by spectral analysis confirm that two known alkaloids (Sterculinine I & II) and three known flavonoids (Gossypetin, Apigenin and 6 Hydroxyluteolin) were purified and characterised from the root ME of Sterculia urens Roxb. The purified and identified compounds were reported for the first time in Sterculia urens Roxb.