| dc.description.abstract | The effect of sunlight intensity to red ginger secondary metabolite has not been known properly. Metabolic profiling can be used to study the correlation between sunlight intensity and secondary metabolite. The profile of volatile metabolite substances from different harvesting time had been examined. Samples of red ginger were harvested in the morning and afternoon. Around 47 volatile substances has been detected using GCMS instrument. Major component that were identified from both harvesting time are camphene, cineol, z-citral, 2,6- octadienol, benzene and α-zingiberene. Antioxidant activity was carried out using DPPH assay. Ascorbic acid was employed as positive control. Essential oil of red ginger was tested using DPPH assay and showed inhibition activities against DPPH radical, nevertheless the inhibition percentage was low and there is not enough prove to show red ginger essential oil have potential as a source of antioxidant. There was no significant difference in radical inhibition activities between both essential oil samples. There was however, a difference in the composition of the volatile component from red ginger essential oil. α-zingiberene compound had showed a significant difference in quantity at different harvesting time under the confirmation of t-test with α=0,05. The quantity of α-zingiberene was higher in afternoon harvesting time. | en |
