Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/15/2002
Publication Date: 1/21/2003
Citation: VANBOVEN, M., LAGA, M., BUSSON, R.R., HOLSER, R.A., DECUYPERE, E., FLO, G., LIEVENS, S., COKELAERE, M. ELIMINATION OF THE APPETITE SUPPRESSING ACTIVITY FROM JOJOBA MEAL BY SODIUM HYDROXIDE TREATMENT: MECHANISM AND ISOLATION OF ISOSIMMONDSIN A. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 2003. Interpretive Summary: A natural compound that can suppress the appetite has been identified in jojoba meal. The biological mechanism by which this occurs is not known. This study examined how the compound reacted with other chemicals in the laboratory. The compound was inactivated when treated with strong base. This information indicates what part of the compound is required to suppress the appetite in animals. An understanding of this biological activity is necessary before the compound may be approved as a therapeutic agent.
Technical Abstract: Jojoba seed meal show appetite suppressing activity due to the presence of simmondsin. This pharmacological activity disappears by treatment of the meal with sodium hydroxide. To elucidate this mechanism of inactivation, the reaction of simmondsin in 1 N sodium hydroxide at 20 C was monitored in function of time. The end products of the reaction as well as intermediates were isolated and identified. The half-live of simmondsin was about 60 min with glucose and 2-hydroxy 3-methoxy phenylacetonitrile as reaction end products. The reaction mechanism could be elucidated by the isolation of isosimmondsin A as an intermediate reaction product. This compound was isolated and purified by a combination of column chromatography and HPLC, and identified mainly by HRMS and NMR spectroscopy. Treatment of isosimmondsin A with 1 N HCl resulted in the formation of a simmondsin lacton derivative.