Antioxidant and Anti-inflammatory Activities of Ethanol and Aqueous Extracts in the Amnouy Suksomjit’s Thai Folk Remedy

Abstract

Introduction: A Thai folk remedy is traditionally used to manage many diseases, such as diabetes mellitus, hyperlipidemia, and dementia, as they are related via oxidative stress and chronic inflammation pathways.
Objectives: This study investigates the antioxidant contents, and anti-oxidation and anti-inflammation properties of ethanol and aqueous extracts of Dr. Amnouy Suksomjit’s Thai folk remedy (RM or the Remedy).
Methods: RM and its plant ingredients were extracted with ethanol maceration and water decoction. All extracts had their antioxidant compounds measured i.e. total phenolic contents (TPC) and total flavonoid contents (TFC), activity by DPPH, ABTS⁺ and FRAP assays, and anti-inflammatory activity by determining the inhibition of nitric oxide (NO) production in LPS-induced RAW264.7 macrophage cells.
Results: The total phenolic contents, measured by TPC assay, for ethanol RM extract (RME) and water extract of the remedy (RMW) were 25.06 and 24.26 mg GAE/g. Extract, respectively. Additionally, the flavonoid contents, determined by TFC, were 87.26 and 85.27mg QE/g Extract for RME and RMW, respectively. RME and RMW exhibited antioxidant activity, with DPPH IC50 values of 56.69 and 46.35 μg/mL, and FRAP values of 20.28 and 13.07 µM TE/g Extract, respectively. RME and RMW showed no anti-ABTS⁺ effect. Furthermore, RME demonstrated a significant anti-inflammatory effect by reducing NO production in lipopolysaccharide (LPS) induced cells, with an IC50 value of 37.68μg/mL, compared to prednisolone’s IC50 value of 51.45μg/mL. Conversely, RMW did not exhibit any anti-inflammatory effect.
Conclusions: The ethanol and the water extracts of the Remedy showed antioxidant effects as found in the phenolics and flavonoids. However, only the ethanolic extract exhibited anti-inflammatory activity. These results support the use of the Remedy for treating diseases related to oxidative stress and inflammation pathways.