Cough-suppressing components in honey identified for the first time in the world

September 29, 2023

A novel compound “melpyrrole” was discovered after more than 10 years of study

Yamada Bee Farm Company, Inc. in collaboration with the RIKEN CSRS and Tokyo University of Science, discovered a novel compound “melpyrrole” as an antitussive (cough-suppressing) component of honey, and verified for the first time in the world that this compound has an antitussive effect comparable to that of the antitussive drug “dextromethorphan.”

The number of people going to a doctor with persisting coughs is increasing in recent years. Coughing is a defensive reaction to eliminate foreign substances that have entered the throat, and it is caused by upper respiratory tract infections with colds and influenza. In general, using antitussive drugs and moistening the throat with water or honey are considered effective.

In this study, the antitussive effect of honey was evaluated in a test using a cough induction model. To investigate the active components in honey, the group fractionated the honey and evaluated each fraction for antitussive effects and compared the composition. As a result of active principle identification and chemical synthesis, the group identified two antitussive components in honey, “melpyrrole” and “flazin,” and found that their activity levels were comparable to dextromethorphan.

The research group plans to continue studying unexplained ingredients and mechanism of action, leading to further understanding of the functionality and assurance of quality of honey.

Original article
Journal of Agricultural and Food Chemistry doi: 10.1021/acs.jafc.3c03864
H. Tani, M. Yamaga, T. Sekiya, Y. Isohama, H. Koshino, T. Nogawa, A. Yamaki, S. Takahashi,
"Identification of a New Pyrrolyl Pyridoindole Alkaloid, Melpyrrole, and Flazin from Honey and Their Cough-Suppressing Effect in Guinea Pigs".
Hiroyuki Koshino
Unit Leader
Molecular Structure Characterization Unit