Preparation of Agricultural Jiaosu from vegetable waste: multi-dimensional effects of microbial inoculants on the properties of Agricultural Jiaosu and fertilizer efficiency

<b>Purpose of the study:</b> To explore the effects of adding different bacterial agents before fermentation on the Agricultural Jiaosu derived from waste from Chinese cabbage. <b>Material and methods:</b> This study used the waste from Chinese cabbage as the raw material and added <i>Lactobacillus</i>, <i>Acetobacter</i>, <i>Yeast</i>, and <i>Bacillus subtilis</i> respectively for fermentation treatment. Systematic research was conducted on the effects of different bacterial agents on the nutritional elements, microbial diversity, organic acid content of Agricultural Jiaosu, as well as their impacts on the growth and yield of Chinese cabbage. <b>Results:</b> The results showed that there were significant differences in the above aspects among the treatments with different bacterial agents. In terms of nutritional elements, the treatment group with <i>Lactobacillus</i> addition had the highest total carbon, total nitrogen, and total phosphorus contents; the treatment group with <i>Acetobacter</i> addition had the highest total potassium and carbon-nitrogen ratio. Microbial diversity analysis revealed that the relative abundance of <i>Bacteroides</i> was higher in the <i>Lactobacillus</i> treatment group; <i>Arcobacter</i> and <i>Vishniacozyma</i> were relatively more abundant in the <i>Acetobacter</i> and <i>Bacillus subtilis</i> treatment groups; and the relative abundance of <i>Lysinibacillus</i> was higher in the <i>Yeast</i> treatment group. Organic acid content analysis indicated that the <i>benzoic acid</i> content was higher in the <i>Lactobacillus</i> treatment group; the <i>benzenepropanoic acid</i>, <i>azelaic acid</i>, and <i>pyroglutamic acid</i> contents were higher in the <i>Acetobacter</i> treatment group; the <i>succinic acid</i> content was the highest in the <i>Yeast</i> treatment group; and the <i>glutaric acid</i> content was the highest in the <i>Bacillus subtilis</i> treatment group. Moreover, the effects of the <i>Yeast</i> and <i>Acetobacter</i> treatment groups on promoting the growth of Chinese cabbage were more significant. <b>Conclusion and future prospective:</b> In conclusion, Agricultural Jiaosu is rich in abundant nutritional elements, diverse microbial communities, and various organic acids, and has a significant fertilizer effect on Chinese cabbage production. Adding different bacterial agents before fermentation leads to differences in the composition and function of the finished Agricultural Jiaosu products. Therefore, appropriate bacterial agents can be selected for fermentation according to specific application goals to optimize the performance and application effect of Agricultural Jiaosu.