Optimization and evaluation of a submerged co-culture fermentation for Trichoderma sp. EGE-K-38 and Bacillus subtilis EGE-B-1.19
Makaleler > Tam Makale · 2026
Yazarlar: Baran MİS, Kemal Karaca, Işıl Aksu
Open Agriculture, SCI Expanded İndekslerine Giren Dergi, Uluslararası, Scopus, 2026, cilt 11, ss 1-14
Özet
Abstract The excessive use of chemical fertilizers and synthetic chemicals in agriculture has resulted in environmental degradation and reduced soil fertility, increasing interest in sustainable alternatives such as microbial biofertilizers. Although Trichoderma and Bacillus species are widely recognized as plant growth-promoting microorganisms (PGPMs), their co-cultivation remains limited due to metabolic incompatibilities that hinder process optimization. This study aimed to develop and optimize a submerged co-culture fermentation process for selected Trichoderma and Bacillus strains to enhance mixed microbial biomass production for biofertilizer applications. Antagonistic interaction screening identified Trichoderma sp. EGE-K-38 and Bacillus subtilis EGE-B-1.19 as compatible strains with minimal inhibitory effects. Comparative mono- and co-culture experiments revealed that medium composition strongly influenced microbial interactions, with YMC (yeast, molasses, corn flour) broth providing the most balanced co-growth. Optimization of physical parameters demonstrated that inoculating Trichoderma sp. EGE-K-38 48 h prior to B. subtilis EGE-B-1.19, using a 1 % inoculum ratio for each strain at 30 °C, resulted in the highest biomass yields. Further medium optimization using response surface methodology identified an economically favorable formulation containing 3 % molasses, 1 % dry yeast, and 1 % corn flour. Under optimized conditions, B. subtilis EGE-B-1.19 reached 1.65 × 10 9 cfu/mL, while Trichoderma sp. EGE-K-38 achieved 1.38 × 10 7 micropropagules/mL.