Stirred-tank bioreactors have been designed for

Options

A. Purification of product
B. Addition of preservatives to the product
C. Availability of oxygen throughout the process
D. Ensuring anaerobic conditions in the culture vessel

Answer

**Step-by-Step Text Solution:**

1. **Understanding Stirred-Tank Bioreactors**: Stirred-tank bioreactors are large vessels designed for biological processes. They are equipped with a stirring mechanism to ensure proper mixing of the contents.

2. **Functions of Stirred-Tank Bioreactors**:
- **Mixing**: The primary function of these bioreactors is to mix the culture medium and the microorganisms or cells effectively.
- **Oxygen Supply**: They are designed to provide adequate oxygen to the culture, which is crucial for aerobic processes.
- **Product Addition and Harvesting**: These bioreactors allow for the continuous addition of substrates and the harvesting of products from the bottom.

3. **Analyzing the Options**:
- **Option A - Purification of Product**: While purification is an important step in bioprocessing, it is not the primary function of stirred-tank bioreactors.
- **Option B - Addition of Preservatives to Product**: This is not a function of stirred-tank bioreactors.
- **Option C - Availability of Oxygen Throughout the Process**: This is a crucial function of stirred-tank bioreactors, as they are designed to maintain aerobic conditions by ensuring a continuous supply of oxygen.
- **Option D - Ensuring an Aerobic Condition**: While related, this option is less specific than option C.

4. **Conclusion**: Based on the functions and design of stirred-tank bioreactors, the correct answer is **Option C - Availability of oxygen throughout the process**.

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