(585c) Isolation, Identification and Quantification of Two Major Antioxidants From Sarang Semut (Myrmecodia pendan)

Sarang semut was extracted with methanol at 45 ^oC for 3 h. The extract was re-dissolved in distilled and successively partitioned with hexane (HEX), dichloromethane, (DCM), ethyl acetate (EtOAc) and n-butanol (BuOH). EtOAc fraction showed the highest DPPH scavenging activity. Two major phenolic compounds, rosmarinic acid and procyanidin B1, were isolated from EtOAc fraction using silica gel column chromatography and gradient solvent system. Rosmarinic acid and procyanidin B1 were obtained with purities of 99.01%, and 98.44%, respectively as determined by HPLC. Their chemical structures were characterized using HPLC–ESI/MS/MS and NMR spectroscopic techniques. The DPPH inhibition power of the two compounds was evaluated.  The IC₅₀ value of proanthocyanidin B1 and rosmarinic acid was found to be 27.59 ±13.50 µg/mL and 35.80 ± 3.79 µg/mL, respectively. The results of this study suggested that the antioxidant activities of these phenolic compounds may be influenced by the number of hydroxyls in their structure. The contents of proanthocyanidin B1 and rosmarinic acid were quantified using HPLC and found to be 3.236 ± 0.280 and 20.688 ± 1.573 mg/g dry sample, respectively.