Currently, the natural micro-organisms antimicrobial preservatives which is produced with microbial metabolites as raw material by extraction, enzymatic conversion and fermentation such as technologies, which is meet the safe and efficient development trends of the food, and which is an important direction and focus of the preservation market. The bacterial strain of SDLH has been isolated from the foregut of Oxya chinensis through experiments, and has been finally identified to as the Serratia marcescens o...