Objective: The optimum extraction technology of total polysaccharides from Agrimonia pilosa was established and its inhibitory activity on human glioblastoma U251 cells in vitro was evaluated. Method: The orthogonal test was implied to optimize the extraction process conditions of total polysaccharides.With the extraction rate as the index

the extraction temperature

extraction time and liquid-material ratio were optimized. MTT assay was used to determine the effect of total polysaccharides on cell growth inhibitory. Morphological changes of the U251 cells were observed through inverted phase contrast microscope. Result: The optimum extraction conditions were determined as following: extraction temperature 90 ℃

extraction time 3 hours and liquid-material ratio of 1∶20.Under these conditions the maximal yield of total polysaccharides reached 1.85%. Total polysaccharides from A. pilosa could inhibit the hyperplasia of glioblastoma U251 cells in dose-dependent manner(P<0.01) and its IC50 reached 1.35 g·L-1. After treatment with polysaccharides U251 cells showed apoptosis morphology. Conclusion: The optimized extraction technology is effective and simple. Total polysaccharides from A. pilosa significantly inhibited tumor cell growth in vitro by inducing apoptosis of tumor cells.