Sustainable Microwave-Assisted Extraction of Bioactive Phytochemicals from ‘Harumanis’ Mango (Mangifera indica L.) Peel Under Optimized Conditions

Agricultural waste, such as Harumanis mango peel represents an underutilized source of bioactive compounds. This study optimized the Microwave-Assisted Extraction (MAE) of bioactive phytochemicals from Harumanis mango (Mangifera indica L.) peel using Box-Behnken design (BBD) under Response Surface Methodology (RSM). Extraction time (20 – 40 s), liquid-to-solid ratio, LSR (10 – 20 mL/g), and ethanol concentration (20 – 80%) were evaluated. Total phenolic content (TPC), total flavonoid content (TFC), and total carotenoid content (TCC) were determined spectrophotometrically, while phytochemical profiling was conducted using UHPLC-Orbitrap MS/MS analysis. Optimal conditions of 35 s, LSR of 18.61 mL/g, and 60.96% ethanol, resulted an extraction yield of 42.90 ± 1.97% and DPPH inhibition of 82.83 ± 3.08%. The optimized Harumanis mango peel extract (HMPE) contained 351 ± 15.31 mg QE/g extract of flavonoid content and 393.60 ± 16.46 mg GAE/g extract of phenolics content. Compared to conventional solvent extraction (CSE), MAE increased extraction yield, TPC, TFC, TCC, and DPPH inhibition by 6.53 %, 28.79 %, 49.82 %, 54.86 %, and 12.58 %, respectively. UHPLC-Orbitrap MS/MS profiling annotated 19 phytochemical compounds, predominantly polyphenols. These results demonstrate MAE as highly efficient and rapid "green" technology for recovering potent antioxidant compounds from Harumanis mango peel waste, providing a practical framework for industrial valorization and sustainable ingredient development.