Abstract
This study investigated the chemical composition and biological activities of Macrochloa tenacissima and Sinapis arvensis using HPLC-DAD and in vitro assays. HPLC analysis revealed that M. tenacissima flowers contained apigenin (1.15 mg/g), luteolin (0.74 mg/g) and epicatechin (0.52 mg/g), along with traces of theobromine, theophylline and coumarins, whereas S. arvensis was rich in caffeic (0.80 mg/g) and ferulic acids (0.09 mg/g). Antioxidant assays demonstrated that methanol extracts of M. tenacissima exhibited strong DPPH (148.45 ± 5.88 µg/mL) and ABTS (50.44 ± 5.94 µg/mL) scavenging, while S. arvensis showed the highest cupric reducing power (138.61 ± 3.17 µg/mL). Enzyme inhibition assays indicated that M. tenacissima exerted the strongest butyrylcholinesterase (446.92 ±23.96 µg/mL) and tyrosinase inhibition (693.57 µg/mL). These findings, representing the first report on M. tenacissima bioactivities, highlight the pharmacological potential of both species as valuable sources of natural antioxidants and enzyme inhibitors.