Progesterone Proof

For the first time, researchers have obtained rigorous evidence that progesterone, a mammalian steroid hormone, is found in a plant (J. Nat. Prod., DOI: 10.1021/np9007415).

Many research groups have hinted at the presence of progesterone in plants—the compound can be made from precursors found in plants such as the Mexican yam. While searching for cytotoxic entities in walnut tree leaves, Guido F. Pauli of the University of Illinois, Chicago, and colleagues isolated small quantities of progesterone and confirmed the hormone's presence by a combination of mass spectrometry and nuclear magnetic resonance techniques. In another plant, the team discovered novel sulfates of progesterone-like compounds.

"This raises fundamental questions about steroid biosynthesis—can all plants make progesterone?" Pauli asks. In mammals, progesterone has several roles, such as preparing the uterine lining for a potential pregnancy, but progesterone's biochemical role in plants is not clear, which warrants further research, he says.

"Although we may have thought we knew that plants contained progesterone, Pauli and colleagues have definitively proven this to be the case," says Charles L. Cantrell, a research chemist at the U.S. Department of Agriculture.

"I consider this to be a major contribution to our knowledge of plant secondary metabolite biosynthesis," says David S. Seigler, who studies the bioactivities of plant-derived compounds at the University of Illinois, Urbana-Champaign.