Research Center for Global Agromedicine, Obihiro University of Agriculture and Veterinary Medicine帯広畜産大学グローバルアグロメディシン研究センター

Lactic acid bacteria are indispensable for the fermentation of milk, and we're very familiar with these microorganisms. Although they have the ability to metabolize the sugar taken into cells and to secrete lactic acid outside bacterial cells, some produce extracellular polysaccharides by connecting lactic acid bacteria with sugar. Since extracellular polysaccharides are extremely diverse in structure, they're expected to have various physiological functions and physical properties. I isolated the MTCC 25067 strain of Lactobacillus fermentum, which produces a high-viscosity extracellular polysaccharide, from dahi (a traditional fermented Indian milk) and clarified the chemical structure and physical properties of the extracellular polysaccharide that it secretes. (Refer to the figure ”Highly viscous yoghurt made with polysaccharide-producing lactic acid bacteria.”)
Although the extracellular polysaccharides that are produced by lactic acid bacteria are very attractive materials from an industrial point of view, there are problems in terms of quality stability and yield. Therefore, extracellular polysaccharides are not applied to industrial use. To overcome this limitation, I aim to produce biosynthesis-related gene-disrupted strains of extracellular polysaccharides and to develop a method to partially synthesize extracellular polysaccharides in vitro.
The ultimate goal is the synthesis of extracellular polysaccharides. I hope to contribute to the food industry by developing useful new technologies related to lactic acid bacteria.