Phytochemical Profile and In Vitro Antioxidant Activity of Ethanolic and Aqueous Extracts of a Kasai Scripture Herbal Compress

Abstract

This study aimed to investigate the preliminary phytochemical constituents, total phenolic content (TPC), total flavonoid content (TFC), and in vitro antioxidant activity (DPPH and ABTS radical scavenging assays) of the herbal compress formulation described in the Kasai Scripture. A 95% ethanolic extract prepared by maceration was compared with an aqueous extract prepared by decoction. The ethanolic extraction yielded 86.25 g (9.58% w/w), whereas the aqueous extraction yielded 73.27 g (8.14% w/w). All experiments were performed in technical triplicate using extracts prepared from a single extraction batch. Preliminary phytochemical screening revealed that both extracts contained tannins, saponins, and terpenoids, whereas alkaloids and cardiac glycosides were detected only in the ethanolic extract. The ethanolic extract exhibited significantly higher total phenolic content and total flavonoid content than the aqueous extract (p < 0.05), with TPC values of 41.06 ± 0.96 and 29.83 ± 0.22 mg GAE/g extract, respectively, and TFC values of 20.28 ± 0.41 and 14.32 ± 0.49 mg CE/g extract, respectively. In the DPPH assay, the aqueous extract demonstrated stronger radical scavenging activity than the ethanolic extract, with IC₅₀ values of 0.83 ± 0.09 and 2.15 ± 0.20 mg/mL, respectively. In the ABTS assay, the ethanolic extract exhibited greater radical scavenging activity than the aqueous extract, with IC₅₀ values of 2.80 ± 0.28 and 4.33 ± 0.22 mg/mL, respectively. These findings indicate that the extraction solvent influences the phytochemical composition and in vitro antioxidant activity of the herbal compress formulation described in the Kasai Scripture. The results provide preliminary scientific evidence supporting further phytochemical characterization and future quality standardization studies of this traditional Thai herbal formulation. However, additional studies are required to identify bioactive compounds and evaluate biological activities before a quality standard can be established.