• 16S rRNA gene;
  • bacterial diversity;
  • Daqu;
  • glucoamylase;
  • α-amylase


Both culture-dependent method and molecular technique were firstly used to simultaneously investigate the cultivable bacterial diversity and amylase production in three typical Daqus of Chinese spirits. The results showed that both cultivable bacterial diversity and amylase production were obviously different. The species of nine bacteria from Deshan, nine from Baisha and six from Wuling Daqus were identified. The total bacterial strains of 17, 15 and 14, and 9, 16 and 10 could produce α-amylase and glucoamylase, respectively, from the Daqus, and the enzyme yields were different. Bacillus licheniformis, Bacillus subtilis and Bacillus amyloliquefaciens not only were dominant bacteria in the Daqus, but also possessed high activities of α-amylase and glucoamylase. By comparison, Bacillus cereus and Bacillus oleronius were found to be another predominant bacterial species and good producers of α-amylase and glucoamylase in Deshan and Wuling Daqus, respectively.