Analysis of beta-N-oxalyl-L-alpha,beta-diaminopropionic acid and homoarginine in Lathyrus sativus by capillary zone electrophoresis

A simple capillary zone electrophoresis (CZE) method has been developed for the simultaneous quantitative determination of beta-N-oxalyl-L-alpha,beta- diaminopropionic acid (beta-ODAP) and homoarginine in Lathyrus sativus (LS; grass pea). A new Na2B4O7-Na2SO4 run buffer was used and the pH was 9.20, contents of beta-ODAP and homoarginine in crude extracts of LS plant materi al were determined with this method, the RSDs of peak areas of beta-ODAP an d homoarginine were 2.62% and 3.61%, respectively. It was found that the eq uilibrium concentration ratio of alpha- and beta-ODAP decreased from 34.5/6 5.5 to 28.6/71.4 when the pH of the solution increased from pH 3.0 to pH 11 .0. (C) 1999 Elsevier Science B.V. All rights reserved.