Identification of tentative antioxidant constituents from stem and leaves of leea indica species using spectroscopic analysis / Fatin Azieyati Baharom …[et al.]

The tentative antioxidative constituents from stem and leaves extracts of Leea indica which
traditionally known as Mali-mali had been investigated. Three different polarities of crude
extracts of each part was prepared using consecutive soaking with petroleum ether,
dichloromethane and methanol. Screening of antioxidants of each extract on TLC was
performed with the use of 2,2 diphenyl-1-picrylhydrazyl (DPPH) as spraying reagent and
have been previously reported. The isolation of antioxidative compounds was performed
through preparative thin layer chromatography(pTLC) with the use of certain binary solvents
system. The structure determination was carried out using Fourier Transform Infra-Red
(FTIR), Gas Chromatography Mass Spectrometer (GCMS) and Proton Nuclear Magnetic
Resonance (NMR) along with comparison with literature. FTIR analysis depicted some
important functional groups such as OH, C-H, C=C and C-O stretching in both parts. The
C=O and C-N stretching only appeared in leaves extract of L. indica. According to proton
NMR spectrum of leaves part, the chemical shifts belonged to aliphatic protons, vinylic
protons, hydroxyl proton and aromatic protons. The proton NMR spectrum of stem part
revealed the existence of proton aliphatic, vinylic proton and hydroxyl proton. Based on
GCMS analysis with the assistance of Wiley 275.L database matching individually as well as
with proton NMR data, the antioxidative compounds isolated from stem part were proposed
as 1-(hydroxymethyl)-1,2- ethanediyl ester (LI-1). 9-Oxononanoic acid methyl ester (LI-2),
9,12-Octadecadienoic acid (LI-3), 3’,8,8’-Trimethoxy-3-piperidyl-2,2’-binaphthalene1,1’,4,4’-tetrone (LI-4).