Fungal Diversity Profiles in Pit Mud Samples from Chinese Strong-Flavour Liquor Pit.

Pit mud, a specific fermented soil, is an essential material for the fermentation of Chinese strong-flavour liquor. However, few studies to date have sought to characterize the spatial profiles of pit mud fungal communities in fermentation cellars from Chinese strong-flavour liquor distilleries. In this analysis, differences in fungal community structures and physicochemical properties in pit mud samples from different spatial positions within fermentation cellars were analyzed, revealing unique characteristic multidimensional pit mud fungal community profiles. , , , , , , , , were dominant in the pit mud samples form the upper cellar wall, whereas , , , , , , , , , were predominant in the middle cellar wall. , , , , , and are majorly present in the down cellar wall layer. , , , , , and were identified as the dominant fungi in pit mud samples from the cellar bottom. Additionally, and are present at notably high levels in all layers of pit mud samples. Moisture, pH, PO, acetic acid, humus, K, Mg, Ca, butyric acid, and caproic acid levels in these different pit mud positions exhibited a rising incremental pattern from the upper wall layer to the bottom layer, whereas lactic acid levels were significantly lower in the bottom pit mud layer relative to these other layers. Moisture, pH, and NH-N were identified as the three most significant factors associated with fungal community composition through a redundancy analysis. Overall, these findings may offer a theoretical foundation for future efforts to improve or standardize artificial pit mud.