Jujube pulp separated from Ziziphus jujube is often discarded after processing, resulting in a serious waste of resources and environmental pollution. Herein, Ziziphus jujube pulp was used as a raw material for vinegar fermentation. To investigate the dynamic distribution of microorganisms and flavor substances in ZJV, correlations between environmental variables (e.g., total acid, reducing sugar, temperature) and flavor substances (organic acids, amino acids, volatile substances) and microorganisms were analyzed. Physicochemical indicators (temperature, total acid, alcohol) were the main factors affecting ZJV fermentation. The middle and later stages of ZJV fermentation were the periods showing the largest accumulation of flavor substances. Organic acids (acetic acid, malic acid, citric acid, lactic acid), amino acids (Asp, Glu, Arg) and volatile substances (ethyl phenylacetate, phenethyl alcohol) were important odor-presenting substances in ZJV. In the bacterial community, the Operational Taxonomic Units (OTUs) with an average relative abundance of more than 10% in at least one fermentation stage were mainly Acetobacter, Lactobacillus and Saccharopolyspora, while it was Thermomyces in the fungal community. Pearson correlation coefficients showed that Penicillium, Lactobacillus and Acetobacter were the core microorganisms, implying that these microorganisms contributed to the flavor formation greatly in ZJV fermentation. This study reveals the correlation between physicochemical indexes and flavor substances and microorganisms in ZJV fermentation. The results of the study can provide a theoretical basis for the development of the ZJV industry.

Trametes sanguinea belongs to the polyporaceae family and it is a white rot medicinal fungus. In the present study, pure mycelium of Trametes sanguinea ZHSJ (T. sanguinea ZHSJ) was obtained from the fruiting body of wild basidiomycetes by tissue separation method, and its growth conditions were optimized in vitro. The results exhibited the optimal growth of T. sanguinea ZHSJ at pH 5, temperature 30 ℃ with the carbon source maltose 20 g/L and nitrogen source yeast extract 4 g/L. LC-MS based untargeted metabolomic studies revealed there are 6715 metabolites in both positive and negative ion mode detection of spores (SP), mycelium (MY) and fruiting body (MU). However, principal component analysis (PCA) represented PC1 67.10% and PC2 24.60% metabolite variance among SP, MY and MU. Further, metabolite cluster and Variable projection importance (VIP) analysis has represented differential upregulated and down regulated metabolites with p value < 0.05 and VIP ≥ 1 significance. Moreover, KEGG pathway enrichment analysis represented SP vs. MY and SP vs. MY major metabolites 23 and 31 involved in biosynthesis of co-factors and MY vs. MU major metabolites involved in diterpenoid biosynthesis. Hence, current study reveals that the morphological stages of T. sanguinea ZHSJ possess several variations in their metabolites and this is the first study to reveal the optimization of T. sanguinea spores and their metabolites comparison with mycelium and fruiting body through LC-MS based untargeted metabolomics. Further research on the biological activity of these differential metabolites of T. sanguinea spores would way a path in identification of novel medicinally important compounds.