[Study on dynamics of tannin in different growth phase of Cynomorium songaricum]

Potassium permanganate titration and complexometry were used to determine the content of tannin in different growth phase of wild and cultivated Cynomorium songaricum Rupr. The result showed that the content appeared regularly changing and the content in coming-up phase was higher than other phases. The quality in this phase would be better if the tannin was regarded as one of the effective components. The result might provide science foundation for the quality control of Herb Cynomorii.