Pulse Electric Field Assisted Extraction of Pinostrobin and Panduratin a from <i>Boesenbergia Rotunda</i> (L.) Mansf. and Biological Assessment on Antioxidation and Glucose Uptake Inhibition

Background: Boesenbergia rotunda (L.) Mansf., a medicinal plant from the Zingiberaceae family native to tropical regions, is valued for its bioactivity properties, commonly used as both a food ingredient and a traditional health tonic remedy. Although it has well-recognized potential as a material source of health products, research on the extraction method for bioactive enrichment remained unexplored. Objective: To improve the extraction process and bioactive content of the plant by using pulse electric field (PEF) extraction compared to the classical extraction method. Methods: Fresh rhizomes were macerated in 95% ethanol for 7, 15, 30, and 60 days for classical extraction. For PEF extraction, 95% ethanol was used as the extraction solvent with time variations of 30 to 150 minutes at a pulse rate of 116 pulses/min and a frequency of 50 Hz. The extraction efficiency was assessed by measuring bioactive compounds, pinostrobin (PS) and panduratin A (PA) using an HPLC assay, along with total flavonoid and phenolic content. Antioxidant activities were evaluated via DPPH, FRAP, and ABTS assays, while glucose uptake inhibition was tested by using a yeast cell model. Results: Classical extraction achieved PS and PA equilibrium after 15 days, recovery of 937-970 mg/kg (0.093-0.097%w/w) and 26-28 mg/kg (0.0026-0.0028%w/w), respectively. PEF extraction optimized at 60 minutes significantly improved recovery with PS at 930±20.35 mg/kg and PA at143.4±3.48 mg/kg (0.014±0.0003%w/w). Additionally, PEF extraction also increased phenolic and flavonoid contents, antioxidant activity, and glucose uptake inhibition. Discussions: PEF achieved a fivefold higher PA recovery than the classical method in just 30 minutes, with results evident after 15 days. Notably, applying PEF to fresh B. rotunda rhizomes in alcohol with metal electrodes induced electroporation, enhancing PS and PA permeability and diffusion from plant material. Conclusion: PEF extraction presents a promising method for efficiently extracting bioactive compounds from Boesenbergia rotunda.