A specific enzymatic procedure for the determination of neurotoxic components (derivatives of L-alpha,beta-diaminopropionic acid) in Lathyrus sativus.

Lathyrus satiVU8 seeds are used to adulterate
some of the common dietary pulses such as Cicer
arietinum (Bengal gram) and Cajanus cajan (Red
gram) in India despite food laws. Chromatographic
or other procedures available for detection
of the neurotoxic or other components in Lathyrus
sotivus are nonspecific. In the present
method, the neurotoxic components (derivatives
of L-a.l3-diaminopropionic acid) are separated by
cation exchange chromatography and subjected diamito
acid hydrolysis. The L-a.I3-diaminopropionic
acid formed was determined using the specific
enzyme diaminopropionate-ammonia lyase. As
little as 50 nm (5 ~g) of L-a,l3-diaminopropionic
acid can be detected by the present method. The
new procedure determines all acid-labile forms of
bound L-a•.B-diaminopropionic acid and extracts
of Cit:er arietinum and Cajanus cajun do not interfere
in the procedure.