Total phenolic and flavonoid compounds, antioxidant and toxicity profile of extract and fractions of paku atai tuber (Angiopteris ferox Copel)

Paku atai plant (Angiopteris ferox Copel), specifically the tuber has been used empirically as an anticancer and antidote materials by Dayaknese in West Kutai, with limited scientific study. Thus, this research had been conducted to determine and evaluate the total phenolic, flavonoid content of this plant along with the antioxidant and toxicity profile. The research used several extracts’ solvents including extraction with ethanol (crude extract, CE) and subsequently partitioned with n-hexane (HF); ethyl acetate (EF) and ethanol aqueous (EAF). The resulted crude extract and fractions were then analyzed through colorimetric method to determine the phenolic and flavonoid total; with DPPH and FRAP to observe the antioxidant activity; and using BSLT method to evaluate the toxicity activity. The results showed that the EF fraction provided the strongest antioxidant activity with IC₅₀ value of 13.79 µg/mL and iron reduction with FRAP value of 387.5±6.41 µM/g. However, a high correlation was observed between the antioxidant and the total phenolic content (r2 = 0.970 - 0.974) but little correlation in total flavonoid (r² = 0.345 - 0.373). Furthermore, the EF (19.56±7.35) showed the highest toxicity activity followed by CE (22.42±2.10), HF (39.52±7.38), and EAF (41.75±5.10). Therefore, the paku atai tuber can be potentially developed as a natural antioxidant and anticancer material.