Isolation of mangiferin and amyloid -protein from n-hexane extract of roots of Wrightia tomentosa

Abstract

The aim of this study is to identify and characterize the bioactive principles from the roots of Wrightia tomentosa. For isolation, the compound, the dried root powder of W. tomentosa was subjected to hot extraction with n-hexane to chromatography. Two compounds (WTRHF 4 and WTRHF 7) were isolated and purified by chloroform: toluene (7.5: 2.5) and chloroform: ethyl acetate (6: 4), respectively. The infra-red (I.R) spectra of WTRHF 4 showed specific absorption bands for proteins, viz., 3689 to 3629 cm-1 for COOH stretching; 2375 cm-1 for NH 3 + stretching; 1726 cm-1 for COO stretching; and the Mass spectrum of WTRHF 4 showed the parent molecular ion (M) + cum base peak at m/z 663.5. In addition, the I.R spectra of WTRHF 7 showed specific absorption bands for flavonoids, viz., 3780 cm-1 for stretching alcohol and phenol; 1098 to 1048 cm-1 for CO -C stretching; 1445 to 1375 cm-1 for O-H δ ip phenol; 1739 cm-1 for C=O stretching and the mass spectra of WTRHF 7 showed a parent molecular ion (M+1) + peak at m/z 423.4 which corresponds to the molecular formula C 19 H 18 O 11. From the physical, chemical and spectral characteristics, WTRHF 4 and WTRHF 7 were concluded as amyloid β-protein (Aβ 17-28) and mangiferin, respectively.

The New Application of UHPLC-DAD-TOF/MS in Identification of Inhibitors on β-Amyloid Fibrillation From Scutellaria baicalensis

“…However, the traditional bioactivity guided separation of active compounds from TCMs, requires repeated rounds of isolation and bioactivity validation before a single active fraction or chemical component can be identified. Due to the disadvantages of being time-consuming and laborious, the traditional way of identifying novel inhibitors on fibrillation of Aβ from TCMs is ineffective with slow progress (Gerardo Castillo et al, 2007; Liu et al, 2011; Kandasamy et al, 2012).…”