Identification of Brazilian Ipomoea carnea toxic compounds

Abstract

In the Convolvulaceae family, the Ipomoeas species are cultivated and found in all regions of the world because of their ornamental bright coloured flowers. It is well known that some Ipomoeas species are toxic. Ipomoea carnea, species of this study, causes depression, general weakness, loss of body weight, stagering gait and death of animals after prolonged periods of plant intake. These toxic effects are attributed to the alkaloids swainsonine and calystegines present in the plant, wich promotes inhibition of galactosidases and manosidases, important enzymes for an adequate metabolism of carbohydrates in the organism. The objective of the present study was to detect and characterize the chemical components of the Brazillian plant. For that, thin layer chromatography, high pressure liquid chromatography coupled to mass spectrometry detector and nuclear ressonance of protons and carbon were used. The aqueous extract of I. carnea presented 0.09% swainsonine, 0.11% calystegine B2, 0.14% of calystegine B1 , 0.06% calystegine C1 and the no proteic imino acid N-methyl-trans-4-hydroxy-L-proline.