Abstract: The present invention provides a method for manufacturing highly-concentrated polyglutamic acid by culturing an aerobic micro-organism of Bascillus sp. with the additional supply of saccharides. The method for manufacturing polyglutamic acid comprises a step of culturing Bascillus sp. in a fed-batch or batch culture while supplying saccharides to the culture. Since the method for manufacturing highly-concentrated polyglutamic acid can be applicable to the industrial scale fermentation, mass production of polyglutamic acid can be feasible in a cost-efficient way.

Abstract: The present invention provides a method for manufacturing highly-concentrated polyglutamic acid by culturing an aerobic micro-organism of Bascillus sp. with the additional supply of saccharides. The method for manufacturing polyglutamic acid comprises a step of culturing Bascillus sp. in a fed-batch or batch culture while supplying saccharides to the culture. Since the method for manufacturing highly-concentrated polyglutamic acid can be applicable to the industrial scale fermentation, mass production of polyglutamic acid can be feasible in a cost-efficient way.

Abstract: The present invention relates to a process for preparing &ggr;-polyglutamic acid (&ggr;-PGA) from high-viscous culture broth, more particularly, to an economical and efficient process for preparing &ggr;-polyglutamic acid from high-viscous culture broth with easy removal of microorganisms and a subsequent concentrating process employing a filtration membrane. The present invention provides the process for preparing &ggr;-polyglutamic acid from high-viscous culture broth which comprises the steps of: culturing &ggr;-polyglutamic acid-producing microorganism for 15-30 hours under condition of pH 5.0-7.5 and 30-40° C. to obtain high-viscous culture broth with a concentration of 20-30 g/L; removing microorganism from the high-viscous culture broth thus obtained by adjusting pH to 2-4 or 7-9 and centrifuging at 3,000-9,000 rpm for 10-50 minutes; and, obtaining &ggr;-polyglutamic acid by concentrating the culture broth employing filter and precipitating &ggr;-polyglutamic acid by addition of alcohol.