This study investigated the diversity of Daqu filamentous fungi and their abilities to synthesize bioactive compounds. High-throughput sequencing was used to study the diversity of filamentous fungi followed by quantitative analysis using fluorescence real-time PCR. Further, culture-depended method was applied to isolate the fungi followed by amplifying the genes involved in secondary metabolites biosynthesis. It was found that the abundance of genus Thermomyces increased with increasing temperature of Daqu, while the abundance of genus Aspergillus decreased. Besides, the biomass of filamentous fungi decreased with temperature. There were 50 filamentous fungal isolates affiliated to 10 genera (Aspergillus, Monascus, Byssochlamys, Lichtheimia, Rhizomucor, Mucor, Arthrinium, Alternaria, Thermomyces, and Rasamsonia) obtained from high temperature Daqu, and these strains had many genes involved in producing secondary metabolites, indicating that Daqu-derived filamentous fungi had great potentials to produce multiple types of secondary metabolites. Therefore, Daqu is a superior reservoir of microorganisms and genes for secondary metabolites biosynthesis, which can be a new source for mining new natural products.
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