The Effect of Glycerol Use in Bacillus Biofertilizer Formulation
Makaleler > Tam Makale · 2026
Yazarlar: Kemal Karaca, Rengin ELTEM
Cureus Journal of Agriculture and Food Science, Uluslararası, 2026
DOI: 10.7759/s44497-026-00099-4
Özet
Bacillus-based plant growth-promoting rhizobacteria (PGPR) biofertilizer formulations have been extensively studied and are widely used in agricultural applications. Following the identification of PGPR traits and optimization of production processes, the development of formulations with adequate shelf-life remains a critical step. To enhance storage stability, various cell protectants are incorporated into formulations, among which glycerol is one of the most used due to its stabilizing and protective properties. In this study, three Bacillus subtilis strains with known PGPR characteristics were evaluated, and an appropriate production medium was selected based on endospore production. Subsequently, B. subtilis EGE-B-1.19 was selected for shelf-life studies. The effect of glycerol addition both during cultivation and after production on viable cell counts was monitored over a 12-month storage period. The results demonstrated that glycerol significantly influenced both biomass production and shelf-life stability. Post-production application of glycerol was found to be more effective in maintaining cell viability compared to its addition during cultivation. Among the tested concentrations, 2% glycerol provided the most favorable results in terms of both viable cell count and pH stability. These findings highlight the importance of glycerol application timing and concentration in the development of stable liquid biofertilizer formulations. Keywords: Bacillus, PGPR, glycerol, biofertilizer, formulation