The invention discloses a method for preparing injection-grade alpha-
cyclodextrin. The method comprises the steps: preparing alpha-CGTase
immobilized enzyme by adopting
epoxy resin as a vector, preparing
starch into
starch milk, adding the alpha-CGTase
immobilized enzyme for liquefying
starch, reacting in a filled reactor filled with the alpha-CGTase
immobilized enzyme, carrying out
ultrafiltration on a conversion solution, and collecting dialysate; treating the dialysate by using alpha-
amylase and saccharifying
enzyme, decolorizing with
activated carbon, concentrating by using
reverse osmosis membrane, recrystallizing, filtrating to remove beta-
cyclodextrin; and further concentrating
mother liquor with a
reverse osmosis membrane, crystallizing, filtrating,
drying and
grinding, thus obtaining the injection-grade alpha-
cyclodextrin. According to the method, the prepared immobilized
enzyme has the advantages that the stability is good, the immobilized
enzyme can be reused; a product and a substrate can be seperated extremely easy, the utilization efficiency of enzymes is high,
continuous operation and automated control can be carried out, the process is simple and convenient, the production cost is low; alpha-cyclodextrin is produced by adopting a
solvent-free process, the production equipment is simple, the
reaction conditions are mild, the
energy consumption is low, and
solvent residual
contamination does not exist, so that the method is very environment-friendly and energy-saving.