Poly-γ-glutamic Acid Production by <i>Bacillus subtilis</i> (natto) under High Salt Conditions

Bacillus subtilis is widely used to produce a variety of fermented soybean foods in Asian countries. These foods are classified into two types: salted (e.g., tuong of Vietnam) and unsalted (e.g., natto of Japan). To explore the effect of salt on the fermentation process, cell growth and the extracellular production of poly-γ-glutamic acid (γPGA), which confers the sticky texture to natto, were examined under high salt conditions (0.5-1.5 M...