Abstract
In this study, endospore-forming bacteria were isolated, screened, and characterized from samples collected in Tan Phu protection forest for potential use in biofertilizer application. Twelve endospore-forming bacteria showed the ability to produce indole-3-acetic acid were evaluated. Based on the relative enzyme activity, siderophore production, phosphate and potassium solubilization, strain CN12 was selected. Strain CN12 was identified as Bacillus amyloliquefaciens based on 16 S rRNA gene sequencing. The liquid culture medium using inexpensive substrates was optimized for increasing its endospore production. The medium consisted of 10% mung bean sprouts extract solution, 0.87% molasses, 0.12% urea, and 0.06% MgSO4 produced the spore yield of 5.53 ± 3.5 (× 108 CFU/mL) for strain CN12. Malabar spinach plants treated with strain CN12 showed significantly increases of 39.4 ± 8.9 to 77.6 ± 11.8 g in fresh weight, 17.1 ± 3.0 to 65.8 ± 17.2 cm in plant height, and 2.9 ± 0.9 to 6.8 ± 2.3 g in root weight compared to the control. These observations revealed that strain CN12 is a promising candidate for biofertilizer production.
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Funding
This research was funded by PetroVietnam Fertilizer and Chemicals Corporation under grant number 138 − 24/PVFCCo/KHCN-KHVLUD/D_UreVSV.
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Tuan Ngoc Nguyen has designed the study. Tu Cam Ly, Nghi Tran, Nhung Hong Nguyen, Thu Thien Pham, Hien My Tran, Thuan Phuoc Dinh, Hung Phi Nguyen, Tuan Ngoc Nguyen performed the experiments. Tuan Ngoc Nguyen conducted the statistical analysis. Tuan Ngoc Nguyen and Rudolf Kiefer wrote the main manuscript.
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Nguyen, T.N., Ly, T.C., Tran, N. et al. Cost-effective plant-based medium for enhanced spore production of B. amyloliquefaciens CN12 for biofertilizer application. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42679-6
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DOI: https://doi.org/10.1038/s41598-026-42679-6
