Microwave‐assisted extraction and comparative antidiabetic potential of avocado seed and Maja fruit extracts

Abstract

This study optimized microwave‐assisted extraction (MAE) to enhance the antidiabetic‐related bioactivity of avocado seed ( Persea americana ) and maja fruit ( Aegle marmelos ) extracts. A one‐factor‐at‐a‐time (OFAT) approach was first applied to both matrices to evaluate the effects of ethanol concentration, irradiation time, and microwave power on extraction yield, total phenolic content (TPC), and α ‐amylase inhibitory activity. The optimal OFAT settings varied depending on the matrix: avocado seed demonstrated the greatest inhibition at 25% ethanol, 21 min, and 450 W, while maja fruit demonstrated the strongest inhibition at 50% ethanol, 16 min, and 300 W. Despite being less effective than acarbose, both extracts showed similar α ‐amylase inhibitory activity, with IC ₅₀ values of 128.31 ± 7.87 μg/mL for maja fruit and 127.91 ± 6.39 μg/mL for avocado seed. Avocado seed was selected for further response surface methodology (RSM) optimization because it showed comparable α ‐amylase inhibition, higher TPC, and stronger 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity. The optimal MAE condition was estimated to be 557 W, 17.97 min, and 51.39% ethanol. Improved IC ₅₀ values of 97.31 ± 4.87 μg/mL and 23.53 ± 4.93 μg/mL were obtained from experimental validation, which yielded α ‐amylase inhibition of 93.19 ± 1.34% and DPPH inhibition of 68.78 ± 1.87%. Enzyme kinetics suggested a non‐competitive inhibition mechanism, while LC‐HRMS profiling revealed distinct putative phytochemical profiles. These findings demonstrate that matrix‐specific MAE combined with RSM can improve the functional bioactivity of underutilized tropical biomasses.