HPLC analysis of the PY and its Ethyl acetate extracts. Standard solution of PY was prepared by dissolving in pure methanol (HPLC grade, 2 g/100 ml). The injection volume was 10 μl and the detection was made at 254 nm. (a) The chromatography of MeOH extract. (b) The chromatography of Ethyl acetate extract. (c) The chromatography of standard compound. Typical result from three independent experiments is shown (*p < 0.05, **p < 0.01, ***p < 0.001).