Objective:To compare differences of pressurized microwave-assisted extraction method(PMAE)

focused microwave-assisted extraction method (FMAE) and post microwave irradiated-reflux extraction method(PMIRE) in extracting alkaloids from Sophora flavescens

and investigate extraction process and microwave mechanism of these 3 kinds of microwave assisted extraction methods. Method: With oxymatrine and matrine as target alkaloids

which were determined by HPLC

thermodynamic functions were calculated by optimizing microwave power

extraction temperature

extraction time

solid-liquid ratio

medicinal granule and other factors

surface structural change of herbs was observed by electronic scanning microscope. Result: Compared with conventional solvent reflux extraction(SRE)

extraction efficiency of PMAE

FMAE and PMIRE increased significantly

ΔH°and ΔS°of alkaloids increased obviously

but ΔG°became smaller.Microwave irradiation could enable cell wall of herbs surface structure to rupture

and strengthen extraction process. Conclusion: Extraction efficiency of alkaloids from S. flavescens with microwave assisted extraction was superior to SRE;Extraction efficiency had large differences by different microwave assisted manners

irradiation degree and extraction process;PMAE had shortest extraction time in the closed system;Because of strong microwave direct role

PMIRE had the best cell-rupture and extraction yield

and its equipment was simple and easy-operating.