| Summary: | Oxidative stress induced by the radicals have been known to affect the
occurrence of various degenerative diseases. Concerns about possible side effects
of synthetic antioxidants cause a shift in the use of natural antioxidants. As the
search for natural antioxidant compounds had been studied the isolation and
identification of antioxidant compounds in fern stems (Alsophila glauca J.Sm)
using DPPH method (2,2-diphenyl-1-picrylhydrazyl). Fern stem extraction was
done by maceration with wasbenzen and metanol. Extracts was obtained by
evaporating the wasbenzen solvent with a rotavapor. Material was re-macerated
with methanol after all wasbenzen evaporation. The same way was done on
wasbenzen to obtain the metanol extract. These extracts were tested for
antioxidant activity using DPPH method with TLC. Active extract was partitioned
in 80% metanol. Extracts both soluble and insoluble in metanol 80% were tested
their antioxidant activity using DPPH method (TLC). Active extract was
fractionated in vacuum liquid chromatography using a mobile phase with different
polarity gradient and different concentrations (wasbenzen:chloroform).
Antioxidant activity of fractions obtained were tested by DPPH method (TLC).
Active fraction was isolated by preparative TLC method and purity of compounds
obtained was tested by TLC. Antioxidant activity of isolates obtained were tested
by DPPH method using spectrophotometry. Compounds known to had antioxidant
activity as radical catcher with IC50 178.4 µg/ml. UV-Vis spectrum of the active
isolates showed absorption max 275, 340, 453, dan 483 nm, indicating the
existence of aromatic compounds. Infrared spectra (KBr) showed absorption at
3402.9 cm
-1
(OH), 2927.9 cm
-1
(CHalifatik), 1261.7 cm
-1
dan 1105.4 cm
-1
(C-O),
1615.8 cm
-1
(C=C aromatic), 1385.5 cm
-1
(CH3). GC-MS spectra gave six peaks.
Peak 1 with a retention time of 15.503 minutes generated a mass spectrum with
molecular ion (M+) appeared at m/z 124. These spectra were estimated 4-fluoro1,2-
xylene compound. Peak 2 with a retention time of 15.737 minutes generated a
mass spectrum with molecular ion peaks (M+) appeared at m/z 206. These spectra
were estimated 4-oxo-alpha-ionone compound. Peak 3 with a retention time of
16.126 minutes generated a mass spectrum with molecular ion peaks (M+)
appeared at m/z 208,1. Peak 4 with a retention time of 17.165 minutes generated a
mass spectrum with molecular ion peaks (M+) appeared at m/z 196. These spectra
were estimated loliolide compound. Peak 5 with a retention time of 18.879
minutes generated a mass spectrum with molecular ion peaks (M+) appeared at
m/z 178. These spectra were estimated methanone,cyclohexyl-1H-imidazol-4-yl
compound. Peak 6 with a retention time of 23.942 minutes generated a mass
spectrum with molecular ion peaks (M+) appeared at m/z 355.
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