Parallel multi-response optimization of reflux and maceration extraction of Sargassum polycystum from the east coast of Pangandaran using Box–Behnken design

Sargassum polycystum contains phenolic- and flavonoid-reactive constituents, although extraction yield and antioxidant quality may respond differently to processing conditions. This study optimized reflux and maceration extraction using response surface methodology–Box–Behnken design and assessed yield–quality trade-offs. Reflux (50–70 °C, 1–3 h, 1:5–1:15) and maceration (24–72 h, 40–80 mesh, 1:5–1:15) were evaluated in 15-run designs for yield, total phenolic content (TPC), total flavonoid content (TFC), and DPPH IC 50 . Reflux yielded 5.46–15.38%, whereas maceration yielded 2.01–15.30%. Maceration achieved a higher maximum TPC (62.98 mg GAE/g) and stronger DPPH activity (IC 50 = 36.19 µg/mL). Optimal conditions were 50.404 °C, 1.0404 h, and 1:9.55 for reflux and 24 h, 80 mesh, and 1:5.30 for maceration. Reflux favored total recovery, whereas maceration produced phenolic-rich extracts with stronger DPPH activity.