Investigation Into the Impact of Solvents on the Phytochemical Composition, Antioxidant Capacities, and Antihyperglycemic Activities of Erigeron annuus (L.) Pers.

This study aims to assess the phytochemical composition, antioxidant potential, and antidiabetic properties of Erigeron annuus (L.) Pers. The ethyl acetate fraction of Erigeron annuus leaves exhibited the highest extraction rate (22.42%). The preliminary qualitative phytochemical analysis in crude extract and fractions is often performed using chemical tests. For quantitative analysis, spectrophotometric methods are widely used to estimate the concentration of phytochemicals. The antioxidant properties were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay, which measures the reduction of Fe³⁺ to Fe²⁺. Qualitative screening revealed the presence of tannins, flavonoids, phenols, saponins, and alkaloids. Notably, the ethyl acetate fraction showed significantly (p < 0.05) higher total phenolic content (70.01 ± 1.1 mg/g) and total flavonoid content (80.29 ± 1.03 mg/g). This fraction also demonstrated substantial α-amylase inhibitory activity and antioxidant potential, suggesting the ability of polyphenols to reduce α-amylase activity. The α-amylase inhibition (23.15 ± 1.22% to 67.31 ± 2.01%) activity and IC₅₀ value (40.59 ± 0.03  μg/mL) were notably higher in the ethyl acetate fraction compared with the standard drug metformin (19.88 ± 1.51  μg/mL). Erigeron annuus ethyl acetate fraction exhibited significantly higher glucose levels (10.88% ± 1.29% to 65.11 ± 0.94%) and conducted a lipid peroxidation experiment utilizing egg yolk as the source of lipids with high content. The most bioactive fraction was evaluated for cytotoxicity against the HEK293 cell line. The cytotoxicity assay revealed that 50% cell viability was observed at a concentration of 50 μg/mL, indicating that the plant extract is nontoxic at concentrations below this threshold. Furthermore, the dominant fraction was further investigated using liquid chromatography-mass spectroscopy and high-performance thin-layer chromatography techniques from the selected plant. Moreover, an in vivo study will be performed to evaluate the antidiabetic efficacy of Erigeron annuus, isolate and characterize its bioactive components, and examine its molecular mechanism of action to improve its therapeutic applicability.