Total phenolic content and antioxidant activities of Sauropus thorelii Leaf extract

Abstract

Sauropus thorelii (Khai Hom) are tropical herbs and acclaimed in Thai folk medicine for the treatment of various diseases; allergy, asthma, common cold, and sinusitis. This mechanism of action may be related to antioxidant properties. The research was aimed to determine total phenolic content and antioxidant activities of Sauropus thorelii leaf extract. Sauropus thorelii leaf extract by using aqueous and ethanol solvent. Total phenolic content was determined by Folin-Ciocalteu method. Antioxidant activities was investigated using DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay and FRAP (Ferric reducing/antioxidant potential). Our results showed that ethanol extract had the total phenolic contents of 17.71±1.05 mg GAE/mg sample. Ethanol extract had the scavenging activity of DPPH radical with IC₅₀ value of 1,380±0.02 mg/ml. Ethanol extract had the reducing power with FRAP value of 190.42±0.01 mg TEAC/mg sample. Aqueous extract had the total phenolic contents of 5.98±0.29 mg/ml GAE/mg sample. Aqueous extract had the scavenging activity of DPPH radical with IC₅₀ value of 11,240±1.33 mg/ml. Aqueous extract had the reducing power with FRAP value of 30.05±0.76 mg TEAC/mg sample. The extract obtained by ethanol was high the total phenolic content and high antioxidant activities than extract obtained by aqueous were statistic significantly at 0.05. These findings suggest that ethanol extract of Sauropus thorelii can be promising sources of potential natural antioxidants.