What is the Difference Between Continuous and Synchronous Culture

The main difference between continuous and synchronous culture is that fresh medium is continuously added in continuous culture, whereas fresh medium is not added in synchronous culture.

Continuous and synchronous cultures are two culture types used to grow microorganisms. They produce therapeutic agents, enzymes, vaccines, etc.  

Key Areas Covered

1. What is Continuous Culture
– Definition, Features, Importance
2. What is Synchronous Culture
– Definition, Features, Importance
3. Similarities Between Continuous and Synchronous Culture
– Outline of Common Features
4. Difference Between Continuous and Synchronous Culture
– Comparison of Key Differences

Key Terms 

Continuous Culture, Synchronous Culture

What is Continuous Culture

Continuous culture is a culture that continuously adds nutrients to the bioreactor. The used culture with metabolites was also readily removed from the bioreactor at the same time. Therefore, the volume of the bioreactor remains constant. A continuous flow system is the key feature of the continuous culture. Also, the optimum conditions are maintained for long-term product synthesis. Importantly, continuous cultures can provide stable product quality. It can give high productivity per unit volume. Additionally, the effluent system can contain products, cells, and residuals. The other key features of continuous culture include equal volumetric flow rate.

Figure 1: Bacterial Culture

Furthermore, continuous culture maintains the exponential growth phase. It avoids the formation of by-products. The by-product formation, microbial growth activity, etc., can monitor the microbial organisms’ activity. The continuous culture is important for producing single-cell protein, starter culture, and organic solvents. Also, it is important for the production of beer, vinegar, fodder yeast, baker’s yeast, etc. 

What is Synchronous Culture

Synchronous culture is a technique that grows microorganisms in a particular growth stage under controlled environmental conditions. Mechanical selection and forced selection are the techniques that maintain the culture at synchrony. Forced techniques use variations in the temperature or nutritional difference. In contrast, mechanical methods use filtration or centrifugation to collect cells at the same stage and size. However, the main characteristic feature of synchronous culture is the growth in the same cell division. Also, the cells of the synchronous culture belong to the same generation time.

Figure 2: Bioreactor

Moreover, synchronous culture gives an idea of the entire cell crop in a particular stage in the life cycle of the microorganism. Also, it is more accessible during growth stages in the cell cycle than other growth techniques of microorganisms. One of the key features of a synchronous culture is the presence of physiologically similar cell types. Also, they grow at the same generation time. 

Similarities Between Continuous and Synchronous Culture

• Continuous and synchronous cultures are two culture types important for producing pharmaceuticals, therapeutic proteins, enzymes, and hormones. 

Difference Between Continuous and Synchronous Culture

Definition

Continuous culture refers to a continuous process where nutrients are continually added to the bioreactor. At the same time, synchronous culture refers to a microbiological culture or a cell culture that contains cells in the same growth stage. 

Nutrients

Nutrients are continuously added to the bioreactor in continuous culture, while nutrients are not added continuously in synchronous culture.

Stage of Cell Division

Continuous culture does not maintain the same stage of cell division, while synchronous culture maintains the same stage of cell division. 

Conclusion

In brief, continuous and synchronous cultures are two types used to produce therapeutic agents, enzymes, hormones, etc. Continuous culture does not maintain the same stage of cell division, but it requires nutrients at a constant rate. In contrast, synchronous culture does not require a continuous addition of nutrients. Also, it maintains the same stage of cell division. Therefore, the main difference between continuous and synchronous culture is the addition of fresh medium.

References:

1. Magar, S. T., & Huy, V. Q. (2021, October 7). Continuous culture- definition, principle, process, types, applications, limitations. Microbe Notes. 
2. N, S. (2021, June 23). What is synchronous culture? definition, purpose & methods. Biology Reader. 

Image Courtesy:

1. “Laboratory bacterial culture” By Soledad Mirand-Rottmann – Own work (CC-BY SA 4.0) via Commons Wikimedia
2. “Bioreactor principle” By YassineMrabet – Own Work (CC-BY SA 3.0) via Commons Wikimedia