Analysis of key factors affecting microbial proliferation during the solid-state fermentation of corn husk-based protein

Corn husk, a significant by-product of the corn deep-processing industry, is currently utilized as coarse feed, yielding very low economic benefits while consuming high amounts of energy and water. This study focused on the high-value utilization of corn husk resources. A two-step enzymatic hydrolysis and combined microbial fermentation was adopted to produce corn husk microbial protein feed. The true protein content was increased by 103% through yeast proliferation. To explore the key driving factors affecting yeast proliferation, a quantitative polymerase chain reaction (qPCR) was adopted to analyze the succession of yeast communities during the fermentation of corn husks. Redundancy analysis (RDA) and variance inflation factor (VIF) were applied to examine the relationship between physicochemical factors and yeast microbial community. The results revealed that, in terms of fermentation time, the uppermost driving factors influencing yeast abundance is moisture content; in terms of contribution, both cellulose content and moisture content serve as the most significant driving factors for yeast proliferation. This research revealed that microbial-enzyme synergy can significantly increase the true protein content of feed, and the key driving factors identified further provide theoretical references for the controllable yeast fermentation.