Enhancement of bioconversion gangliosides to monosialotetrahexosylganglioside by in situ sialic acid removal and recovery

Abstract

Monosialotetrahexosylganglioside (GM1) production via bioconversion from gangliosides is promising for industrial application because it has the advantages of a high GM1 yield and an environmentally friendly process. Sialidase hydrolyzes gangliosides to GM1 producing sialic acid as a by‐product, which inhibits the sialidase activity, while the incomplete conversion of gangliosides was indicated by thin‐layer chromatography (TLC) in the presence of sialic acid. The sialic acid showed competitive inhibition on the sialidase activity with an inhibition constant of 0.75 mmol/L. By harnessing the in situ product removal (ISPR) technique, 50 g/L of crude gangliosides was completely converted to GM1 after a 12 h conversion. The GM1 concentration increased from 0.42 to 10.88 g/L in the ISPR system, which was 59.1 % higher than that of the control (6.84 g/L GM1). In addition, sialic acid was recovered simultaneously with a yield of 74.7 %. In summary, the ISPR system improved the bioconversion from gangliosides to GM1 and recovered sialic acid within a one‐step bioprocess.