[Variations of the essential oils in Acorua calamus L. and their major compositions]

The variations of the essential oils in Acorus calamus and their major compositions with seasons and producing areas were investigated by steam distillation and internal standard method. The result has shown that June is the best season for A. calamus cropping and that the major components of the volatile oil in the same part of the plant from different producing areas have the same chemical structure type.