Toxicology and the chemical foundation of plants of Erycibe.

Erycibe is a relatively small genus in the family Convolvulaceae with over 10 identified species. Some Erycibe plant species are purportedly toxic at high doses. However, few toxicology studies have been conducted on those species. In this study, the toxicity of 40% ethanolic extracts of Erycibeobtusifolia, Erycibeschmidtii, and Erycibeellipptimba was evaluated. E. ellipptimba has been reported to be more toxic due to containing larger amounts of Baogongteng C, an alkaloid with known toxicity. Thus, E. ellipptimba was chosen for further toxicology study here. An HPLC-MS method was developed to identify the main components and determine the percentages of Baogongteng C in total alkaloid of E. ellipptimba (EWA). The toxicity of total alkaloid and Baogongteng C was evaluated and compared. The results indicated that Baogongteng A and Baogongteng C are the major toxic chemical compounds of the Erycibe species tested. The results also suggest EWA is cholinergic. Finally, in a subacute toxicity study of EWA, alterations observed with high dosage suggest that the liver and kidney could be the target organs of toxicity.