China is the largest country of cultivating sweet potato in the world.The resources of sweet potato leaves are huge.At present,leaves are seldom utilized.This causes the waste of resources and pollution of environment.To exploit the rich resources,the method of separating and content determining polyphenol in ipomoea lam leaves by HPLC was established.Furthermore,dynamic changes in the content of polyphenol from ipomoea lam leaves in different periods and the craft condition of extraction of antioxi...