Investigation of microbial community involved in fermentation of Massa Medicata Fermentata

This study aimed to clarify the microbial diversity, dominant species and the change of community structures in the fermentation of Liushenqu(Massa Medicata Fermentata), and explore the material foundation of its pharmacodynamics effect. On the basis of standardizing the fermentation process, Massa Medicata Fermentata was prepared by screening and optimizing the recipes and the standard formula issued by the Ministry. The community structure and growth process of fungi and bacteria in the samples at five time points(0, 17, 41, 48, 65 h) in the fermentation process of Massa Medicata Fermentata were analyzed by using isolation and culture of eight different media and high-throughput DNA sequencing technology. The results indicated that the samples of the two recipes pre-sented high microbial diversity at the initial fermentation stage, with Aspergillus spp. as the dominant species. As the fermentation process goes forward, Saccharomycopsis fibuligera and Rhizopus oryzae soon became dominant species from 17 h after fermentation commencement point to the fermentation end, while the other species were inhibited at a lower level from 17 h. The species diversity of bacteria in the initial fermentation samples was also high, and Enterobacter was the dominant species. Enterobacter cloacae, Pediococcus pentosaceus and Cronobacter sakazakii became dominant bacterial species 17 h after fermentation commencement, while the species diversity was decreased. Our results will be a scientific basis for promoting the fermentation process of Massa Medicata Fermentata by using pure microbial cultures.