Conversion of Food Waste and Feldspar into Biofertilizer Using a Stress-Tolerant Keldspar-Solubilizing Bacillus Subtilis Xue-113168

To develop high-efficient biofertilizer, a chemical fertilizer stress-tolerant feldspar-solubilizing Bacillus subtilis Xue-113168 was isolated from soil, and breed, with resistance against multiple environmental stresses, including 20–50 °C temperature, 4–10 pH range, 0–12.5% (w/v) K2O and 0–0.5 M phosphate. The Bacillus subtilis Xue-113168 was used to convert food waste and feldspar to a potassium biofertilizer through a solid fermentation (SSF) process. After fermentation of 7 days, spore density can be increased to 2 × 109 CFU/g. The control of pH and temperature humidity effectively lead to the formation of spore and potassium dissolving rate of 41.53%. Results confirmed that solid state fermentation presents considerable advantages compared to the complex process (solid-state and bioleach).Compound Microbial Fertilizer (CMF) formulated with humic acid, K2HPO4, and biofertilizer have the advantage of a quick and long-lasting effect. Provisional registration certificate of CMF is No. 3878 by Ministry of Agriculture of the People’s Republic of China in March 15, 2017. CMF promote the sustainable development of the agriculture industry.