Bioprocessing Part 1: Fermentation

Introduction

This tutorial outlines the fermentation process as discussed in the Bioprocessing Part 1 video. It details the significance of fermentation in producing biological products, particularly focusing on the production of Green Fluorescent Protein (GFP). The tutorial will cover types of fermentation, cellular characteristics, nutrient requirements, and key production parameters essential for successful fermentation.

Step 1: Understand Types of Fermentation

Familiarize yourself with the two main types of fermentation:

• Intracellular Fermentation: Involves fermentation occurring within the cells. This process is typically more efficient for metabolic products.
• Extracellular Fermentation: Occurs outside the cells. This method allows for easier extraction of products from the fermentation broth.

Step 2: Differentiate Cell Types

Recognize the two types of cells involved in fermentation:

• Aerobic Cells: Require oxygen to grow and metabolize. They are typically more efficient in energy production.
• Anaerobic Cells: Thrive in the absence of oxygen. These cells often produce energy through fermentation processes.

Step 3: Prepare Cell Nutrition

Understand the importance of media components for cell growth:

• Carbon Sources: Provide energy; commonly glucose or other sugars.
• Nitrogen Sources: Essential for protein synthesis; could be yeast extract or ammonium salts.
• Minerals and Vitamins: Support various cellular functions; include trace minerals and specific vitamins.
• Buffers: Help maintain pH levels during fermentation.

Step 4: Grow Seed Stock

Initiate the fermentation process by growing seed stock:

1. Inoculate a small volume of nutrient media with a selected strain.
2. Allow the culture to grow until it reaches the exponential growth phase.
3. Monitor growth parameters like temperature and pH to ensure optimal conditions.

Step 5: Scale Up the Process

Transition from seed stock to larger fermentation tanks:

1. Transfer the seed culture into a larger fermenter.
2. Maintain the optimal conditions identified during the seed stock growth.
3. Gradually increase the volume to prevent shock to the cells.

Step 6: Monitor Growth Phases

Track the life cycle growth pattern of the cells:

• Lag Phase: Initial period where cells adapt to the new environment.
• Exponential/Log Phase: Rapid cell division and growth occurs.
• Stationary Phase: Growth rate slows as nutrients deplete and waste products accumulate.
• Death Phase: Cells begin to die due to unfavorable conditions.

Step 7: Monitor Production Parameters

Ensure successful fermentation by monitoring key production parameters:

• Time: Keep track of the fermentation duration.
• Temperature: Maintain appropriate temperatures for the specific cell type.
• Pressure: Monitor pressure levels in the fermenter to prevent issues.
• pH: Regularly check and adjust pH to optimal levels.
• Agitation: Ensure proper mixing to maintain uniformity and oxygen transfer.

Conclusion

In summary, fermentation is a crucial process for producing biological products like GFP. Understanding the types of fermentation, cell characteristics, nutrient requirements, growth phases, and production parameters is essential for successful outcomes. As you continue to explore bioprocessing, consider experimenting with different types of cells and fermentation conditions to optimize production. For additional resources, visit NC BioNetwork.