Free radical scavenging of Pseuderatherum Platiferum Extract from Dong Mahawan Subdistrict, Wiang Chiang Rung District, Chiang Rai Province

Abstract

        The objective of this research was to investigate the antioxidant activity and total phenolic content of crude extracts from the Phaya Wanorn herb (Pseuderatherum Platiferum), a plant traditionally used in Thai medicine. Extraction was performed using three solvents of different polarities 99.8% ethanol, methanol, and water to compare their efficiency in extracting bioactive compounds. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The total phenolic content was analyzed using the Folin-Ciocalteu method, with absorbance measured by a spectrophotometer. The results showed that all three extracts of Pseuderatherum Platiferum exhibited DPPH radical scavenging activity. The methanol extract demonstrated the highest antioxidant activity (IC₅₀​ = 0.15±0.01 mg/ml), followed by the water extract (IC₅₀​ = 0.18±0.01 mg/ml) and the ethanol extract (IC₅₀​ = 0.20±0.01 mg/ml), respectively. The lower IC₅₀​ values indicate significantly higher antioxidant efficacy. Furthermore, the analysis of total phenolic content revealed that the methanol extract had the highest polyphenol content (20.50±0.50 mg GAE/g Extract), followed by the water extract (17.40±0.35 mg GAE/g Extract) and the ethanol extract (15.20±0.40 mg GAE/g Extract). This study concluded that the antioxidant activity of the Pseuderatherum Platiferum extracts is directly correlated with the quantity of extracted phenolic compounds. This suggests that the extracts, particularly the methanol extract, have the potential for development into dietary supplements or herbal medicines for the prevention and treatment of diseases associated with free radicals.