In vitro antioxidant activity and Content of compounds from Curculigo orchioides rhizome

Curculigo orchioides Gaertn. is used in traditional medicine in Vietnam. Its antioxidant potential was evaluated through DPPH radical scavenging and the total antioxidant capacity method. The data resulted from DPPH radical scavenging activity indicate that Curculigo orchioides display high activity with a low IC50 value (22.78μg/mL), approximately 1.5 times less than that of curcumin (34.34 μg/mL). The total antioxidant capacity of the extract is equivalent to 132.48 ± 1.48 mg GA/g or 264.45 ± 2.34 μmol AS/g. The composition of Curculigo orchioides, including the total phenolic, total flavonoid, polysaccharides, and triterpenoid saponins, was examined by using the colorimetric method with reagents, and their quantity is equivalent to 196.24 ± 1.45 mg GAE/g, 78.49 ± 1.78 mg QE/g, 4.34 ± 0.08 %, 47.60 ± 0.24 mg Rb1/g (Rb1: Gypenoside III), respectively. Specifically, the total triterpenoid saponins content of Curculigo orchioides has been reported for the first time.