TITLE:
Directional Breeding of High Itaconic Acid Yielding Strain of Aspergillus terreus with a New Plate Technique
AUTHORS:
Lingyun Wei, Jianhua Wang, Hezhi Zhou, Wenbiao Jin, Zhangli Hu, Jiazuan Ni
KEYWORDS:
Aspergillus terreus; Itaconic Acid; Corn Starch; Dextrose Equivalent; Enzymatic Hydrolysis
JOURNAL NAME:
Advances in Microbiology,
Vol.3 No.4,
August
6,
2013
ABSTRACT: Itaconic acid is commercially produced by
the cultivation of Aspergillus terreus using starch hydrolysate as carbon source. The degree of hydrolysis had a great
influence on itaconic acid production which was suitable when corn starch was saccharified at 35 DE. The α-amylase was sufficient
to drive the starch hydrolysis to the degree. The agar plate assay with LiCl
treatment provided a rapid, simple and unequivocal
method for screening large numbers of colonies for itaconic acid producing
strains. It was learned by experience that the strains on the plates with thick
hyphae and light-colored spores often accompanied high itaconic acid
production. A strain, designated Ast165, producing itaconic acid with a high
yield, was successfully obtained by directional breeding of metabolic end
products resistant strains. The itaconic acid concentration produced by Ast165
was 53.8 g/l from 100 g/l of starch hydrolysate in shake
flasks. The conversion rate was 61.3%, which was the highest value found in
tests.