Lupeol: An antioxidant triterpene in Ficus pseudopalma Blanco (Moraceae)

Abstract

Objective: To assess the antioxidant activity of Ficus pseudopalma Blanco (Moraceae) (F. pseudopalma) and characterize the active components present in it. Methods: Column chromatography of crude ethanol leaf extract of F. pseudopalma was performed and seven fractions were obtained, labeled as F1, F2, F3, F4, F5, F6, F7. DPPH, FRAP, Griess, Fenton and superoxide radical scavenging assays were performed to assess the antioxidant ability of the fractions. Thin layer chromatography (TLC), high performance liquid chromatography and Fourier transfer infrared spectroscopy (FTIR) were performed to identify and characterize the bioactive component present in each fractions of F. pseudopalma. Results: DPPH and FRAP assay showed that F5, F6 and F7 exhibited the good proton accepting ability and reducing power as compared to the other fractions. All fractions exhibited a good nitric oxide radical scavenging activity wherein F1, F2 and F3 showed the highest inhibition. However, all of the fractions exhibited a stimulatory activity on hydroxyl and superoxide radicals. Lupeol matched one of the spots on the thin layer chromatography chromatogram of the fractions. Linear gradient high performance liquid chromatography and spiking of lupeol with the fraction revealed the presence of 5.84 mg/L lupeol in F6. Infrared spectra of the fractions revealed the presence of C-C, OH, aromatic C=C and C=O groups. Conclusions: The identified lupeol in F. pseudopalma may be responsible for the exhibited antioxidant property of the plant. Furthermore, knowing the antioxidant capability of the plant, F. pseudopalma can be developed into products which can help prevent the occurrence of oxidative stress related diseases.

Keywords

• Antioxidant
• Oxidative stress
• Free radical scavenging
• Reducing power
• Phenolic acids
• Ficus pseudopalma Blanco