[Determination of effective time of Schizonepeta tenuifalia pieces by classical constant temperature acceleration experiment].

To study the validity of Schizonepeta tenuifalia pieces. The change principle for the contents of essential oil and pulegone was determined by the way of classical constant temperature acceleration experiment, and the reacting speed at 20 degrees C was calculated according to Arrhenius index law and effective time was calculated. In classical constant temperature experiment, the content change of essential oil with the regular pattern of one level. The effective time of S. tenuifalia pieces stored in 20 degrees C was 2.08 years and the constant of speed is 8.453 4 x 10(-6) carried out by essentialoil, 190 days with the constant of speed is 3.39 x 10(-5) carried out by pulegone. The effective time of S. tenuifalia pieces was about 2 years carried out by essential oil and 190 days carried out by pulegone by the way of classical constant temperature experiment.