Biotechnology Bulletin ›› 2014, Vol. 0 ›› Issue (4): 159-163.

• Report • Previous Articles     Next Articles

Screening,Identification and Characterization of an Acid q-amylase Producing Strain and Optimization of Its Fermentable Condition

Wang Jianling, Chen Zhixin, Liu Yihan, Lu Fuping   

  1. (Key Laboratory of Industrial Fermentation Microbiology,Ministry of Education,College of Biotechnology,Tianjin University of Science& Technology,Tianjin 300457)
  • Received:2013-10-23 Online:2014-04-29 Published:2014-04-29

Abstract: Multiple new acid α-amylase producing strains were isolated from soil which is rich in starch. A strain which has the highest enzyme activity was identified as Bacillus subtilis A-7 through analysis of 16S rDNA gene. The optimum temperature and pH was 60℃ and 4.5. The single factor experiments and orthogonal experiments were adopted to optimize the liquid fermentation medium. The composition of the best medium was 2% soluble starch, 2% peptone, 0.07% CaCl2, 0.8% Na2HPO4. Under this optimal condition, the activity of acid α-amylase was 221 U/mL and 2.3-fold more than that of no optimization.

Key words: Acid α-amylase 16S, rDNA, Bacillus subtilis, Optimum temperature, Optimum pH, Orthogonal experiment