Ultrasound-assisted extraction combined with analytical characterization for the identification of a novel chalcone from Cambuci peel

Cambuci ( Campomanesia phaea (O. Berg) Landrum) is a Brazilian native fruit that has received limited scientific investigation. However, in recent years, its production has expanded, creating new opportunities to investigate the fruit and valorize the by-products generated during its processing. The cambuci peel, as the main by-product, presents significant interest for exploration using environmentally friendly extraction techniques, such as ultrasound-assisted extraction (UAE). Accordingly, a Box–Behnken design (BBD) was applied to optimize the recovery of total phenolic compounds (TPC) from cambuci peel. Ethanol concentration, temperature, amplitude, and ultrasound cycle were selected as key variables for the study. The optimal extraction conditions were 62.3% ethanol, 45.4 °C, 70% amplitude, a 1 s −1 cycle, and 10 min of extraction. After establishing these optimal conditions, method repeatability and intermediate precision resulted in coefficients of variation below 5%, confirming its applicability. Under optimal conditions, an antioxidant capacity of 24.059 ± 0.043 mg g −1 was obtained. The sugars identified in the sample were fructose (42.13 ± 1.60 mg g −1 ) and glucose (19.02 ± 1.05 mg g −1 ), along with an ascorbic acid content of 158.19 ± 3.36 mg g −1 . Additionally, two chalcones were identified, one of which is being described for the first time in scientific literature. This study aimed to expand the chemical knowledge of the species and to highlight the potential of cambuci peel for future applications. The sustainability analysis shows that ultrasound-assisted extraction of cambuci peel aligns with some principles of the Path2Green metric, achieving a score of 0.080, which is more favorable than maceration and Soxhlet extraction. This study highlights the importance of exploring novel raw materials to support waste valorization and enable a wide range of industrial applications.