Abstract:The core material was prepared through the self-made zeolite loaded potassium diformate (KDF) by hydrothermal method, the sodium alginate (SA) and chitosan (CS) were used as shell material, then the sustained-release microcapsules were prepared between core material and shell material by a complex coac-ervation method. The structure was characterized by FT-IR and XPS, the performance was characterized by sustained release and inhibition rate experiment. The results show that a compounding effect can be formed between the zeolite and the KDF to form a core material of the microcapsules, CS and SA form a polyelectrolyte membrane through electrostatic interaction, which constitutes the shell material of the microcapsules. The microcapsules were stable in the simulated stomach environment with pH=2.0, KDF of microcapsules were released in the intestinal environment of pH=7.2 and can be completely released within 3 h. The entrapment efficiency was 68.33%, the release amount of KDF in microcapsules were 137.50 mg/g. The prepared microcapsules have an inhibitory effect on the growth of E. coli, and the inhibition rate with E. coli increases with the increase of the concentration of microcapsules and the highest inhibition rate can reach 85%.