Enhanced Wheat Straw Bioconversion via Bacillus spp. Inoculation: Advancing Sustainable, High-Value Compost Production

Wheat straw, as a lignocellulosic residue, can be effectively converted into compost, representing a sustainable approach to agro-industrial waste management. This study investigates the effect of inoculating wheat straw with Bacillus strains on composting dynamics and organic matter degradation efficiency, with implications for soil quality improvement and environmental sustainability. Compost maturity and quality were evaluated through chemical and biological parameters over a 40-day period. Results showed that Bacillus -inoculated compost exhibited traits of a stable and mature product: the NH ₄ ⁺-N/NO ₃ ⁻-N ratio was 0.625, the C/N ratio was 25.88, and the pH was 7.26. The mineral composition of the inoculated compost was significantly increased compared to the control compost, namely: Ca (36%), Mg (58%), Cu (62%), and Zn (75%), with the greatest increase observed in Mn concentration (threefold). Phosphorus content in the treated compost increased eightfold compared to the initial value and exceeded that of the control. The germination index of white mustard seeds ( Sinapis alba L. ) was 30% higher in the inoculated sample. Bacillus strains accelerated the degradation of lignocellulosic material derived from wheat straw, yielding a mineral-rich, phytotoxin-free compost suitable for agricultural application and with enhanced biofertilization potential.