title: Improvement of production of Kojic acid by a mutant strain Aspergillus oryzae, MK107-39.
abstract: A strain designated MK107-39, producing kojic acid with a high yield, was obtained by a new screening method using a 96-well microtiter plate after NTG treatment of Aspergillus oryze ATCC 22788. The amount of kojic acid produced by strain MK107-39 in a shaking flask was 28 g/l from 100 g/l of glucose, which was 7.7-times higher than that produced by parent strain. The kojic acid yields per cell and the amount of glucose consumed were 9.8 and 6.0-times higher than those of the parent strain. Based on differences in the use of carbohydrates and organic acids, it seems that strain MK107-39 has some mutation regarding carbohydrate metabolism. By customizing the medium and culture conditions such as glucose concentration, dissolved oxygen concentration and pH of the fermentation broth, more than 110 g/l of kojic acid was produced in a 3-l jar fermentor. Upon scale up to a 600-l pilot fermentor, enhanced production of kojic acid was successfully achieved. The kojic acid yield from glucose consumed, Y(P/S), was 0.43 (g/g) in this pilot plant-scale fermentation.
authors.affiliation: United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Futamura
authors.forename: M
authors.initials: M
authors.lastname: Okabe
authors.forename: T
authors.initials: T
authors.lastname: Tamura
authors.forename: K
authors.initials: K
authors.lastname: Toda
authors.forename: T
authors.initials: T
authors.lastname: Matsunobu
authors.forename: Y S
authors.initials: YS
authors.lastname: Park