Fourteen species of Erythrina were characterized for the total alkaloids content, both in the form and as glycosides, by gas chromatography-mass spectrometry. Thirteen alkaloids were identified in all, the most common being erysodine, erysovine, and erysopine. A number of unknown or unidentified were also noted. In two previous papers (Games et al., 1974; Barakat et al., 1977) we described preliminary studies of the occurrence of alkaloids in the seeds of some 26 species of Erythrina. In the present work we have continued using gas chromatographymass spectrometry (g.c./m.s.) to analyze the alkaloid content of 14 further species, and as in the earlier studies (Barakat et al., 1977), we have characterized the total alkaloids occurring both in the free form and as their glycosides; the latter were hydrolyzed to enable the liberated alkaloids to be analyzed. Hydroxyl groups were derivatized as their trimethylsilyl (TMS) derivatives before g.c./m.s., and the individual alkaloids present in each species were characterized by comparisons of their mass spectra with those of authentic materials isolated from other species, and with data reported in the literature. A number of new alkaloids were also detected in the course of this work, but full characterization will depend on the availability of sufficient seeds for preparative isolation of the alkaloids concerned. ALKALOIDS IN ERYTHRINA SPECIES The results of the present studies with the seeds of 14 species are shown in Table 1, and for comparison earlier findings by other workers with nine of these species are recorded in Table 2. The previous work depended largely on classical separation methods, i.e., crystallization and column chromatography, the one exception being Rinehart's investigations (Hargreaves et al., 1974) of Erythrina flabelliformis seeds, which like our own work involved g.c./m.s. As indicated' in the list of sources of seeds used in our studies, several diferent samples of seeds collected at different times (some were more than 30 years old), or in different 1 Our previous two papers (Games et al., 1974; Barakat et al., 1977) are regarded as parts I and II. 2 We are very grateful to B. A. Krukoff for supplying all the seeds used in this work, and for his keen interest in the results. We are also pleased to record our gratitude for a grant towards this work from the F. B. and B. A. Krukoff Memorial Fund, and we thank the S.R.C. for assistance in the purchase of the mass spectrometer used in this work. We thank Mr. M. Rossiter for assistance in running the mass spectra. 'Department of Chemistry, University College, Cardiff, Wales. 4 Correspondence should be addressed to Dr. A. H. Jackson, University College, P.O. Box 78, Cardiff, CF1 1XL, Wales. ANN. MissouRi BOT. GARD. 66: 533-540. 1979. 0026-6493/79/0533-0540/$00.95/0 This content downloaded from 207.46.13.101 on Sat, 08 Oct 2016 04:39:57 UTC All use subject to http://about.jstor.org/terms