Assessment of Cellulolytic, Potassium and Phosphate Solubilizing of Bacteria from Bali Cattle Rumen as Potential Compost Bioactivators

Rumen fluid of Bali cattle contains a highly diverse and functionally active bacterial community, offering valuable potential for compost bioactivation. This study aimed to isolate and characterize cellulolytic, phosphate and potassium-solubilizing bacteria from the rumen and assess their roles in supporting composting processes. A range of bacterial isolates was successfully obtained and grown on selective media, revealing distinct functional groups including those capable of degrading cellulose, solubilizing phosphate and potassium, fixing nitrogen, and producing Indole-3-Acetic Acid (IAA). Functional screening using clear zone assays confirmed enzymatic activities related to organic matter decomposition and nutrient solubilization. Several isolates exhibited multifunctional traits, demonstrating simultaneous activity across multiple biochemical processes. These findings highlight the ability of rumen-derived bacteria to accelerate composting, enhance nutrient availability and improve the overall compost quality. The results support the application of these indigenous bacterial strains as effective bioactivators in sustainable composting systems and organic waste management strategies.