Valorization of Baru (Dipteryx alata) Peel and Pulp Residues Through Sequential Solvent Fractionation: Recovery of a Chalcone- and Aurone-Rich Bioactive Extract

Baru (Dipteryx alata Vogel) processing generates underused peel and pulp residues. This study investigated sequential solvent fractionation as an analytical proof of concept for phenolic recovery. Residues were extracted successively with hexane, chloroform, ethanol, and water. The ethanolic fraction represented 4.72% of the initial dry biomass and was characterized by HPLC-DAD-ESI/MS and functional assays. Butein and sulfuretin were confirmed against authentic standards; additional chalcone- and aurone-related peaks were tentatively annotated. Together, these assignments accounted for approximately 93% of summed chromatographic quantities, an estimate dependent on surrogate-standard calibration and identification uncertainty. The fraction showed responses in DPPH, ABTS, and FRAP assays, which require assay-specific interpretation. Separate IC50 values were 117.20 ± 4.10 µg/mL for pancreatic lipase, 461.67 ± 21.80 µg/mL for α-amylase, and 82.35 ± 5.40 µg/mL for porcine pancreatic elastase. These values do not establish enzyme selectivity. Bacterial MIC values were 5–10 mg/mL, without detectable bactericidal activity up to 10 mg/mL. Resazurin responses differed with concentration and cell line. The results identify a chemically distinctive fraction for further investigation while retaining limitations in structural assignment, quantitative reporting, mass balance, residual-solvent assessment, and application safety.