Prof. Dr. Megga Ratnasari Pikoli M.Si. invited the students of biology study programme of FST UIN Jakarta to visit Biofertilizer Manufacturer PT Belani Natura Bioriset in Bandung on 29 November 2024 last year. The aim was for the students to see the bioreactor for biofertiliser production.
A bioreactor is a controlled system used to grow microorganisms (bacteria, fungi, algae) or enzymes that play a role in the production of biofertilisers. The following is an explanation of bioreactors for biofertiliser production:
1. Types of Bioreactors Used
Several types of bioreactors are commonly used in biofertiliser production:
- Batch Bioreactor: Microbial cultures are grown in a closed medium until they reach maximum population, then harvested.
- Continuous Bioreactor: Media and microbes are continuously flowed, allowing for more stable production.
- Fed-Batch Bioreactor: A combination of batch and continuous, with gradual addition of nutrients to increase yield.
- Solid-State Bioreactor (SSF): Used for microbes growing on solid substrates (such as agricultural waste).
2. Main Components of a Bioreactor
Fermentation Tank: A place for microbial growth with temperature, pH, and aeration settings.
- Aeration & Stirrer System: Ensures oxygen is available for aerobic microbes.
- Sterilisation System: Prevents contamination from other microbes.
- Sensors & Automatic Controls: Monitors environmental conditions (temperature, pH, O₂)
3. Biofertiliser Production Process in Bioreactors
- Microbial Selection: Selecting superior strains (e.g. Rhizobium, Azotobacter, Pseudomonas, Mycorrhiza).
- Culture Media: Using carbon (molasses, organic waste) and nitrogen sources.
- Inoculation & Fermentation: Microbes are cultured in a bioreactor for 24-72 hours.
- Harvesting & Formulation: Microbial cells are separated and mixed with carrier material (husk charcoal, peat, clay).
- Packaging: Packaged in liquid or solid form.
4. Advantages of Bioreactors in Biofertiliser Production
- Optimal Control: Fermentation conditions can be adjusted for maximum yield.
- Scalability: Can be produced on a small (lab) to industrial scale.
- Quality Consistency: Microbial population is more stable than traditional methods.
5. Application Example
- Rhizobium fertiliser: Produced in bioreactors for soybean & legume inoculants.
- PGPR (Plant Growth Promoting Rhizobacteria) Fertiliser: Plant growth promoting bacteria.
- Algae Biofertiliser: Spirulina or Azolla produced in a photosynthetic bioreactor.
6. Development Challenges
- High initial cost for industrial-scale bioreactors.
- Need expertise in operation and maintenance.
- Risk of contamination if sterilisation is poor.
Conclusion
Bioreactors enable efficient production of biofertilisers with controlled quality. Their use is growing with the demand for sustainable agriculture and reduction of chemical fertilisers.