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Context: Monosialotetrahexosylganglioside (GM1) prepared from the brain of pig or bovine is an effective clinical drug in the treatment of different nervous system diseases. Generally, polysialogangliosides are transformed into GM1 by enzymic or chemical hydrolysis due to the very poor level of natural GM1. Objective: To continuously obtain GM1 by cell immobilization in a packed-bed reactor. Materials and methods: Brevibacterium casei, which is Gram-positive bacteria belonging to the order Actinomyces and family Brevibacteriaceae, can produce high-activity sialidase, are encapsulated in silk fibroin hydrogel, and subsequently packed into a reactor. The crude ganglioside is pumped into the reactor and continuously turned to GM1. Results: The optimal silk fibroin concentration for hydrogel preparation is 6.0% (w/v). The optimal initial biomass for immobilization is ~12% (wet weight). The optimal conversion conditions are 35°°C and 6 mL/min of flow rate. Under above conditions, the maximum GM1 productive strength and conversion ratio can reach to 4.2 g/L··h and 313.5%, respectively. Discussion: Silk fibroin is a promising material for cell immobilization because it has predominant characteristics of higher permeability and intensity. Cell immobilization for continuous GM1 transformation could eliminate the asialo GM1 and decrease the foreign matter from transfer medium and metabolism product. Conclusion: In the packed-bed reactor, continuous production of GM1 had been under effective running at least for 15 days indicating a potential for industrial production. It is significant that this is a first report on cell immobilization for GM1 production. [ABSTRACT FROM AUTHOR]