Sustainable Extraction of Phytochemicals from Leucaena leucocephala Leaves: Integrating Laccase Pretreatment with Microwave-Assisted Hydrodistillation

Leucaena leucocephala leaves are a promising biomass for the extraction of bioactive phytochemicals.However, their complex lignocellulosic matrix limits the extraction process.Thus, this study evaluates a green strategy by incorporating laccase pretreatment with microwave-assisted hydrodistillation (MAHD).L.leucocephala leaves were pretreated under optimized conditions (0.55 mg mL⁻¹ laccase, pH 4.5, 60 °C, 6 h) and subsequently extracted by MAHD (250 W) across controlled time (0 -48 min) and temperature (30-70 °C) ranges.Total flavonoid content (TFC) and total coumarin content (TCC) were quantified.In addition, SEM was employed to assess structural changes.Laccase pretreatment has successfully disrupted L.leucocephala cell wall and increased its porosity.It also enhances phytochemical recovery if compared to MAHD alone.The results show that TFC was increased by 5.3 % and TCC by 74.5 % in the presence of laccase pretreatment, follow by MAHD.Process optimization identified 36 min and 60 °C as the best MAHD conditions, balancing mass transfer with thermal stability.The integrated approach reduced temperature and residence time relative to conventional extraction, aligning with green-chemistry principles.These findings demonstrate that laccase assisted MAHD extraction improves the recovery of flavonoids and coumarins from L. leucocephala and supports the valorization of this fast-growing biomass for nutraceutical and pharmaceutical applications.