| Summary: | The strains with high protease production were isolated and screened from various sources to provide strain resources for microbial fermentation of corn gluten meal to produce corn peptide, also to provide strain resources for the value-added and comprehensive utilization of corn gluten meal.The strains were screened by corn gluten meal medium and Folinol method, and were identified by 16S rDNA sequences.The activity and growth characteristics of the target strain protease were further studied.The result showed that 405 bacteria strains were isolated and 58 strains had transparent hydrolytic circles from corn gluten meal medium plates.The strains were classified into 4 families, 5 genera, 17 species and 2 subspecies, including members of Bacillus, Lactobacillus and Planomicrobium.And the Bacillus spp.was the most abundant.The target strains can secrete alkaline, acidic and neutral proteases, and most of the strains show higher alkaline protease activity.Eight strains were selected and their growth characteristics were studied.The optimal growth temperature and pH were 30-40 ℃ and 7～9, respectively.The protease activity and growth characteristics showed the strain specificity.
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