Abstract
An enzymatic method for the differential measurement of 1, 4-diguanidinobutane (DGB), agmatine, and putrescine was developed. DGB and agmatine were converted to N-carbamoylagmatine and N-carbamoylputrescine respectively, with agmatine deiminase from Rhodococcus sp. C-x. The initial concentration of DGB was determined from the final concentrations of the guanidino groups of N-carbamoylagmatine. The sum of the initial concentrations of DGB and agmatine was determined from the final concentration of the ureido groups. The concentration of putrescine was measured with putrescine oxidase from Micrococcus rubens IFO 3768; which had no activity toward agmatine. Three of the four commercial preparations of agmatine sulfate tested were found to contain 21-32% (w/w) of DGB and putrescine.
