Abstract:

Bacterial populations of three samples of Maotai-flavored Daqu in Zunyi, Guizhou province were studied.
Principal component analysis was used to evaluate the relationship between bacterial population and Daqu. The 454 FLX+
platform was used to sequence the 16S rDNA gene V3–V5 region of the bacteria. The high quality sequences were clustered
by similarity (0.97), and used to calculate the relative content of bacteria. Through principal component analysis, we
analyzed the bacterial population of Daqu. Results showed that 6 phyla and 49 genera were detected from three samples,
and the Firmicutes were the most dominant phylum. Thermoactinomyce (34.40%), Bacillus (31.40%) and Scopulibacillus
(13.60%) were dominant in Daqu MT01, accounting for 79.40% of the total bacterial population. Thermoactinomyce (34.80%)
and Bacillus (49.00%) were dominant in Daqu ZJ01, accounting for 84.80%. Only Thermoactinomyce (66.10%) was
dominant in Daqu ZX01. Principal component analysis (PCA) suggested that MT01 and ZJ01 were the nearest in distance,
and ZX01 was a little far. This study can provide a theoretical basis for the judgment of Daqu quality.

Key words: Maotai-flavored Daqu, bacteria, high-throughput sequence, population, principal component analysis