Abstract
The content of berberine in the barks of trunk, branches, and twigs from one tree, as a condition for collection, was determined with phellodendron obtained from Phellodendron japonicum. The content in these three parts was found to decrease in that order, approximately in proportion to the diameter of the particular portion examined. The relationship between the time of collection and berberine content was found to be independent of each other, the content being the maximum in July at 3.09%, that in June being 2.68%, in August, 2.88%, and an average of 2.28-2.44% in other months. It follows, therefore, that collection of barks from large trees during the summer would furnish materials of excellent quality.
