Spatio-temporal scales of the Chinese Daqu microbiome: Heterogeneity, niche differentiation, and assembly mechanisms

Abstract

Background

Daqu-making is an ancient biotechnology that has been continually iterated and upgraded over thousands of years. The main objective was to promote microbial spectrum formation by consistently adjusting the Daqu niche. Due to Daqu processing across temporal and spatial scales, the aggregation and formation of Daqu microbial communities are influenced by many scales. However, how the spatio-temporal scales regulate Daqu microbiome formation is still shrouded in mist, significantly hindering the stability and standardization of Daqu quality.

Scope and approach

This study reviews the evolution of Daqu production. Moreover, it comprehensively synthesized the diversity, structural characteristics, and niche differentiation of the Daqu microbiome on both spatial and temporal scales. The assembly mechanism of the Daqu microbiome was systematically investigated. Finally, it discusses the challenges and future directions of Daqu manufacturing.

Key findings and conclusions

The Daqu microbiome has a scale effect, and its assembly involves both initial and successional community assemblies. The biological influx and community coalescence shaped the Daqu initial niche. Next, the microbial community of Daqu exhibited a periodic arrangement in the time series, which was mediated by environmental factors at various scales and microbial interactions, including physical contact, cross-feeding, nutritional competition, quorum sensing, biofilm formation, and toxic substances. In the future, the advancement of knowledge regarding the microecological stabilization of Daqu fermentation and intelligent brewing of Daqu will facilitate the sustainable development of the Daqu industry.