Optimization of Ultrasound‐Assisted Extraction Conditions for Phenolic Content and Antioxidant Activity in Green Mango Peel Using Response Surface Methodology

ABSTRACT Green mango peel ( Mangifera indica L.) is an abundant agro‐industrial by‐product rich in phenolic compounds with strong antioxidant potential, making it a promising source of natural bioactives for food and nutraceutical applications. However, efficient extraction conditions for maximizing these compounds remain insufficiently established. This study aimed to optimize ultrasound‐assisted extraction (UAE) conditions for total phenolic content (TPC), DPPH radical scavenging activity, and reducing power from green mango peel using response surface methodology (RSM). A three‐factor, three‐level Box–Behnken design (BBD) was employed to investigate the effects of extraction time (10–30 min), temperature (30°C–60°C), and ethanol concentration (30%–70%). A total of 17 experimental runs were conducted, and second‐order polynomial models were developed for all responses. The adequacy of the models was confirmed by analysis of variance (ANOVA), which showed that all independent variables significantly influenced TPC, DPPH, and reducing power ( p < 0.01). The models demonstrated strong statistical performance, with R 2 values of 0.9976, 0.9943, and 0.9989, and adjusted R 2 values of 0.9754, 0.9707, and 0.9827 for TPC, DPPH, and reducing power, respectively. The predicted R 2 values (0.8302, 0.7966, and 0.8794) further indicate good model reliability and acceptable predictive capability. RSM optimization identified the optimal extraction conditions as 36.25°C, 12 min, and 53.75% ethanol concentration. Under these conditions, the experimental values for TPC, DPPH radical scavenging activity, and reducing power were 28 ± 1.5 mg GAE/g DW, 58% ± 2%, and 46 ± 1.8 mg AAE/g DW, respectively, which closely matched the predicted values, confirming the validity of the developed models. Overall, the study demonstrates that UAE combined with RSM is an efficient, reliable, and green extraction strategy for recovering phenolic compounds from green mango peel. The optimized process supports the sustainable valorization of agro‐industrial waste and highlights the potential of mango peel as a functional ingredient source for antioxidant‐rich food and nutraceutical applications.