Metabolomic profiling and antioxidant activity of Araucaria bidwillii leaves and twigs: a comparative study of biflavonoids content

Abstract This study compared the metabolite composition and antioxidant capacity of acetone and methanolic extracts from the leaves (LAc and LMet) and twigs (Tac and TMet) of Araucaria bidwillii , with particular emphasis on biflavonoid profiling and quantification. LC-MS/MS analysis identified agathisflavone-, amentoflavone-, and cupressuflavone-type biflavonoids in both leaves and twigs. 7,4′,7″,4‴-Tetra- O -methylcupressuflavone and two unidentified metabolites were exclusively found in leaves, and kolaflavanone was detected only in twigs. Among all extracts, LAc exhibited the most diverse metabolite profile and the highest abundance of methylated biflavonoids. HPLC-DAD analysis confirmed that LAc contained the highest levels of target biflavonoids, with 7,4′,7″-tri- O -methylcupressuflavone being the predominant compound (0.2618 ± 0.0132 mg/g). LAc exhibited superior antioxidant performance in CUPRAC assays, whereas LMet showed the highest FRAP value. These findings indicate that antioxidant capacity is influenced not only by the total abundance of phenolic compounds but also by their qualitative composition, particularly the distribution of biflavonoids. Overall, the results demonstrate that acetone is more effective than methanol for recovering biflavonoid-rich fractions from A. bidwillii leaves. The combination of a diverse metabolite profile, high biflavonoid content, and strong antioxidant activity identifies LAc as the most promising extract for future bioactivity-guided isolation and pharmacological investigations of biflavonoids from A. bidwillii .