The occurrence of putrescine and a new guanidino amino acid in seeds of Lathyrus tingitanus

Abstract

The natural occurrence of L-homoarginine in seeds of Lathyrus sativus ( Rao, Ramachandran and Adiga, 1963), of L. cicera , L. cymenum and others ( Bell, 1962a) has recently been noted. Further, seeds of L. tingitanus contain the unusual amino acid lathyrine — β-(2-amino-pyrimidine-4-yl) alanine ( Bell, 1962b). The possible role of homoarginine as a precursor of lathyrine has been suggested ( Rao et al. , 1963 ; Bell, 1962c), and it has also been speculated that γ-hydroxyhomoarginine or its lactone — which may spontaneously undergo ring closure to yield tetrahydrolathyrine — could be expected to occur in L. tingitanus ( Rao et al. , 1963 ). We present herein some evidence for the presence of a new guanidino amino acid in the seeds. Some of the properties noted for this amino acid are akin to those anticipated for the lactone of γ-hydroxyhomoarginine. The seeds also contain a substantial amount of putrescine.