ESTROGENIC SUBSTANCES. II. AN ANALYSIS OF PLANT SOURCES

Abstract

Alcohol or chloroform extracts of various types of fresh plant material were saponified and extracted in alkaline solution with ether. The ether extracts (unsaponifiable material) were suspended in physiological saline or dissolved in oil of sesame, and these preparations injected into castrated $ mice to determine their capability of initiating estrus. Positive results (cornification of vaginal epithelium as shown by microscopic examination of vaginal smears) were obtained with only a few of the substances studied; alder leaves and catkins, willow catkins, sprouted oats and young rhubarb leaves. Mature leaves, fruits, roots and tubers were negative. The highest concentrations observed were 1 mouse unit per 12 gm. of original material ([female] willow catkins), and 1 mouse unit per 20 gm. ([male] willow catkins, alder catkins, alder leaves, sprouted oats). The authors conclude that relatively high concentrations of estrogenic material occur in plants (1) associated with green pigmentation, and (2) coincidently with rapid growth.