Characterization and Optimization of the Ultrasound-Assisted Extraction Process of an Unexplored Amazonian Drupe (Chondrodendron tomentosum): A Novel Source of Anthocyanins and Phenolic Compounds

This study presents the first comprehensive physicochemical and bioactive characterization of the fruit of Chondrodendron tomentosum Ruiz & Pav. (Menispermaceae). Biometric and physicochemical parameters were characterized across three fruit ripening stages (green, turning, ripe). Additionally, proximate composition was determined in ripe fruits, and methanol concentration (25–75%), ultrasonic amplitude (30–70%), and time (1–15 min) were optimized using response surface methodology with a Box–Behnken design. During ripening, weight increased by +47.7% (3.89 to 5.74 g; p < 0.0001), TSS by +26.1% (7.00 to 8.83 °Brix), pH decreased by 32.0% (6.28 to 4.27), and acidity increased by 276% (0.25 to 0.94%). The quadratic models demonstrated high predictive accuracy (R2 > 96.5%; p < 0.004). Optimal conditions (57% methanol, 70% amplitude, and 15 min) maximized total anthocyanin content (120.71 ± 1.89 mg cyanidin-3-glucoside/L), total phenols (672.46 ± 5.84 mg GAE/100 g), and DPPH radical scavenging capacity (5857.55 ± 60.20 µmol Trolox/100 g) in ripe fruits. Unripe fruits do not contain anthocyanins, reaching 46.01 mg C3G/L in turning fruits and 120.71 mg/L in ripe fruits (162% higher than turning fruits). Principal component analysis (90.6% variance) revealed synchronized co-accumulation of anthocyanins and phenols, enhanced by vacuolar acidification. These results suggest ripe C. tomentosum fruits as a potential source for natural colorants, nutraceuticals, and functional foods, pending prior development of green, human-safe extraction processes.