Which of the following is an advantage of a bioreactor which uses continuous culture system rather than batch culture?

Options

A. It provides required growth conditions like temperature, pH substrate, salts, vitamins and oxygen
B. The transformed recombinant cells are allowed to grow in a large bioreactor till maximum amount of biochemical has been formed.
C. the bioreactor is made empty, cleaned and a fresh medium is added
D. There is a regular drainage of the medium and culture cells from one side and fresh medium from the other side leading to higher yield of desired product

Answer

**Step-by-Step Solution:**

1. **Understanding Culture Types**: There are three main types of culture systems in bioreactors: batch culture, fed-batch culture, and continuous culture. Each has its own characteristics and applications.

2. **Batch Culture**: In a batch culture system, nutrients are not added once the culture starts, and the waste products are not removed. This can lead to a decline in growth as waste accumulates and nutrients deplete.

3. **Fed-Batch Culture**: This system allows for the addition of nutrients during the culture process. This helps maintain growth for a longer period compared to batch culture but still has limitations regarding waste removal.

4. **Continuous Culture**: In a continuous culture system, there is a constant addition of fresh media while simultaneously removing old media that contains waste products, dead cells, and toxic substances. This ensures that the culture environment remains optimal for growth.

5. **Advantages of Continuous Culture**:
- **Regular Drainage**: Continuous removal of waste and dead cells prevents toxicity and allows for a healthier environment for the organisms.
- **Active Growth Phase**: Cells remain in the exponential phase of growth, which is the most active phase for producing desired products. This leads to higher yields of the product.
- **Higher Yield**: The continuous supply of nutrients and removal of waste leads to a sustained and higher yield of the desired product compared to batch or fed-batch cultures.

6. **Conclusion**: The primary advantage of a continuous culture system over a batch culture system is the regular drainage of media and culture cells, along with the addition of fresh media, which results in higher yields of the desired product.

**Final Answer**: The advantage of a bioreactor using a continuous culture system rather than a batch culture is that there is a regular drainage of the medium and culture cells from one side and fresh medium from the other side, leading to a higher yield of the desired product.

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