The invention belongs to the technical field of biological
catalysis, and relates to a biological preparation method of
agmatine sulfate, which comprises the following steps: by using an L-
arginine sulfate solution as a substrate
raw material, carrying out
decarboxylation reaction in the presence of a biocatalyst and a coenzyme to obtain
agmatine sulfate, and discharging gas CO2, wherein the biocatalyst adopts L-
arginine decarboxylase, and the coenzyme adopts phosphopyridoxal. The L-
arginine sulfate solution used as the substrate is stirred and mixed with the L-arginine decarboxylase and the coenzyme (phosphopyridoxal) to perform
decarboxylation reaction under certain conditions, thereby obtaining the
agmatine sulfate. The conversion rate is greater than or equal to 98%, and the
continuous production yield can reach 90%. The technical
route has the advantages of simple preparation technique, high production efficiency, low cost and the like. The
fermentation and conversion techniques of the recombinant L-arginine decarboxylase can achieve the industrial preparation level, thereby basically solving the problems of high
chemical synthesis cost, low yield, and great environmental hidden danger and the like.