Insights into Fermentors and Bioreactors for Cell Culture and Laboratory Fermentation

Question

Accepted Answer

Question 1: What is the main difference between a fermentor and a bioreactor?

A fermentor is typically used for microbial cultures, while a bioreactor is designed for a broader range of cell types, including mammalian cells. However, the terms are often used interchangeably, and the key distinction lies in the specific application and the type of cells being cultivated.

Question 2: How is the sterility maintained in a laboratory fermenter or bioreactor?

Sterility is maintained through rigorous cleaning and sterilization procedures before use. This may involve autoclaving, chemical sterilants, or filtration. Additionally, aseptic techniques are employed during operation to prevent the introduction of contaminants.

Question 3: What factors influence the choice of a fermentor or bioreactor for a specific cell culture application?

The choice depends on factors such as the type of cells (microbial, plant, or mammalian), the scale of production (laboratory or industrial), the required control parameters (temperature, pH, dissolved oxygen), and the nature of the product being produced.

Question 4: How is the oxygen supply managed in a cell culture bioreactor?

Oxygen can be supplied through various methods such as sparging with air or pure oxygen, using membrane oxygenators, or by adjusting the agitation speed to enhance gas exchange at the liquid surface.

Question 5: Can a laboratory fermenter or bioreactor be scaled up for industrial production?

Yes, but scaling up requires careful consideration of factors such as mass transfer, heat transfer, and fluid dynamics. The process parameters need to be re-optimized to ensure consistent performance at the larger scale.

Question 6: What are the common monitoring parameters in a fermentation bioreactor?

Common parameters include cell density, metabolite concentrations, pH, temperature, dissolved oxygen, and carbon dioxide levels. These parameters provide valuable information for process control and optimization.

Question 7: How often should the culture medium be changed in a cell culture bioreactor?

The frequency of medium change depends on the cell type, growth rate, and the depletion of nutrients and accumulation of waste products. It can range from daily to several days, and is determined based on ongoing monitoring and analysis.

Question 8: What types of sensors are commonly used in a fermentor or bioreactor for data collection?

Sensors for pH, dissolved oxygen, temperature, pressure, and optical density (for cell density measurement) are commonly employed. Some advanced systems may also include sensors for specific metabolites or biomarkers.

Question 9: How is the pH controlled in a fermentation process?

pH is controlled by adding acids or bases as needed. Automated pH control systems use pH sensors to trigger the addition of the appropriate substances to maintain the desired pH range.

Question 10: What safety precautions should be taken when operating a fermenter or bioreactor?

Safety precautions include proper training of operators, wearing appropriate protective equipment, ensuring the integrity of pressure vessels, and having emergency response plans in place for potential leaks or equipment failures.