Characterization of the antioxidant activity, identified free radical-relieving components by LC/QTOF/MS and acute oral toxicity studies of Tri-Tharn-Thip tea

Abstract

This study assessed the antioxidant activities and bioactive maker of Tri-Than-Thip tea (Tri-TTa) to provide database support for the use of Tri-Than Thip remedy according to the Thai Pharmaceutical Textbook and aims to develop herbal medicine or food from natural products. Tri-TTa and herbal components were tested for antioxidant scavenging activity (DPPH assay, ABTS assay), chain-breaking/iron ion chelating activity (Metal Chelating Activity; MAC, the ferric-reducing antioxidant power activity; FRAP), superoxide anion radical scavenging activity (NBT assay), oxygen radical antioxidant capacity (ORAC assay), total content of Phenolic (TCP) and flavonoid (TCP) substance. The chemical components were separated and investigated by LC/QTOF/MS for safe dosages due to acute oral toxicity in rats. The Tri-TTa showed the strongest inhibition of antioxidant activity with the DPPH, ABTS, and MCA assay, with IC50 values of 0.087 ± 0.003, 0.025 ± 0.000, and 0.012 ± 0.000 mg/mL, respectively. In addition, Tri-TTa can also inhibit superoxide anion radicals, with IC50 values of 158 ± 0.009 mg/mL, and the oxygen radical was 3.47 ± 0.03 μM of TE/g extract. TCP, TCF, and FRAP values of Tri-TTa were 154.123 ± 1.326, 80.233 ± 14.268 mg equivalent/g of extract, and 1092.457 ± 106.024 mM FeSO4/mg, respectively. Additionally, Tri-TTa contains important substances in the phenolic and flavonoid groups that have good antioxidant abilities and were confirmed to be safe through acute oral toxicity testing in rats, which revealed no toxicity-related effects at high doses. Tri-TTa is a strong candidate for use as a natural product with antioxidant activity, suggesting that plant polyphenol content may promote antioxidant activity. These results support further research on Thai folk remedy infusions as promising antioxidant agents that can be developed for food, tea, or tonic drugs from natural.