Profil Metabolit Volatil Rimpang Temulawak (Curcuma xanthorrhiza Roxb.) yang Dipanen pada Waktu Berbeda.

Abstract

Yield and composition of secondary metabolites in plants can be affected in many factors, such as harvesting time in a day. Metabolite profiling necessary to explain the influence of harvesting time in a day in volatile metabolites composition of temulawak essential oil. GC-MS analysis used to distinguish the changes in volatile metabolites of temulawak essential oil at different harvesting time. The aims of this research is to explain the influence of harvesting time in composition volatile metabolites temulawak essential oil and their correlation with their bioactivity as antioxidant. A total of 25 volatile compound were identified by GC-MS analysis. The major volatile component in both harvesting time are α- cedrene, α-curcumene, and xanthorrhizol with m/z 204, 202, and 218. The in vitro antioxidant activity was investigated with radical DPPH scavenging assay, ascorbic acid was employed as positive control. The result showed that temulawak essential oil has an antioxidant property, with the IC50 of 3.24x109 ppm in morning and 1.15x1013 ppm in afternoon harvesting time. The essential oil showed radical scavenging, but lower than ascorbic acid. There is no significant different in composition of volatile metabolite and radical scavenging activity of temulawak essential oil with different harvesting time in α=0,05.