When we mention bioprocesses, we are entering the world in which living cells - think bacteria, fungi, or human cells – transform and synthesize compounds essential for human consumption and industrial use. Bioprocesses harness the potential of microorganisms or biological systems to carry out targeted tasks, ranging from the production of pharmaceuticals and foodstuffs to crafting diverse chemical compounds.
While these processes have been utilized for centuries, they operated largely unknown and uncontrolled in ancient times. Consider the making of beer, wine, or bread: It’s a testament to how cells like baker’s yeast quietly executed remarkable transformations, turning sugars to alcohol and carbon dioxide without the brewer or baker grasping the science behind the scenes.
Nowadays, these and many, many more bioprocesses are well-studied and tightly controlled. The understanding and awareness about environmental factors influencing these processes continue to advance, enabling scientists to constantly optimize bioprocesses, improve product yields and quality, and avoid unwanted by-products. Even the slightest deviations in conditions, such as temperature or pH levels, can have significant impacts on the entire process.
It is therefore widely acknowledged that enhanced bioprocess insights and the control of specific key parameters make bioprocesses more easily predictable, manageable, and positively impact the outcome.
What is considered a critical process parameter?
In the context of a bioprocess, a Critical Process Parameter (CPP) is a measurable and controllable key variable that directly shapes the outcome and efficiency of a biological process. These parameters play a crucial role in determining how well the process operates. Process parameters span a broad spectrum, encompassing physical, chemical, and biological factors. The specific parameters that require monitoring can vary based on the unique characteristics and goals of different bioprocesses. Nonetheless, certain parameters consistently stand out as top priorities in the majority of fermentations.
Ready to Discover the Top 5 Parameters? Here's Our List!
1. Dissolved Oxygen
Dissolved oxygen, often abbreviated as DO, is a critical parameter in bioprocesses involving aerobic microorganisms. It represents the amount of oxygen dissolved in the liquid medium and is crucial for the survival and optimal performance of oxygen-dependent organisms. In bioprocessing, maintaining an adequate level of dissolved oxygen is paramount as it directly influences cell growth, metabolism, and the production of desired compounds. Insufficient levels of dissolved oxygen can lead to decreased cell viability and compromised process efficiency.
Various methods are employed to measure oxygen in a culture. Traditional approaches often involve measuring the partial pressure of oxygen. Alternatively, optical methods, such as fluorescence-based sensors or spectroscopy, offer non-invasive ways to monitor dissolved oxygen levels.
Want to learn more about DO monitoring in microbial bioprocessing? Check out the Application Page!
2. pH
pH, a measure of the acidity or alkalinity of a solution, is a fundamental parameter in bioprocessing. Its significance lies in its profound influence on various biological and chemical reactions, including microbial growth and enzyme activity, making it a critical factor for the success of bioprocesses.
Different organisms thrive in specific pH ranges, and deviations can lead to inhibited growth or undesirable metabolic shifts. The precise control of pH in bioprocesses, achieved through methods such as chemical indicators, electrodes, or spectroscopy, ensures the creation of an environment favorable to produce desired compounds. Automated pH controllers and dedicated equipment facilitate real-time assessment, allowing for immediate adjustments to maintain the ideal pH conditions.
In essence, pH serves as a compass, guiding the bioprocess towards favorable conditions and optimal outcomes. Visit the Application Page to learn all about it!
3. Biomass
Biomass, in the microbial context, refers to the entity of cells in a culture, serving as a crucial parameter that embodies microbial or cellular growth within a fermentation process. The accumulation of biomass is often a primary objective in processes leveraging microorganisms for valuable compound production. Beyond its role in yield, biomass provides insights into the viability and health of cells, also serving as an indicator for potential contaminations. Growth curves play a pivotal role in assessing bioprocesses, fostering reproducibility when similar curves are observed between fermentation runs.
For more in-depth information on biomass and how it is monitored, visit our Biomass Application Page.
4. Temperature
Temperature, a central parameter in bioprocessing, profoundly influences microbial activities and enzymatic reactions. The right temperature serves as a catalyst for optimal cell growth, metabolism, and the production of target compounds, while deviations may compromise these results. Both excessively high and low temperatures can impede cellular activities, resulting in decreased productivity or undesirable by-products. Temperature variations also impact the solubility of gases crucial for certain processes. Therefore, continuous monitoring and adjustment of temperature, facilitated by sophisticated heating or cooling systems, are fundamental to consistently achieving high-quality outcomes in bioprocessing.
5. Substrate or nutrient concentration
Substrates, such as sugars, alcohols, or fatty acids, often serve as the raw materials for the desired product and act as the fuel for cellular activities. Nutrients, such as vitamins or minerals, provide essential building blocks for cell development. Achieving the right balance of substrate and nutrient concentrations is fundamental for optimizing bioprocesses. Insufficient concentrations may limit microbial growth and compromise product yields, while excesses can lead to wasteful metabolic pathways or undesirable by-products. Therefore, it is desirable to monitor and control these concentrations to track substrate and nutrient consumption and analyze bioprocesses.
Conclusion
From dissolved oxygen and pH to biomass, temperature, and substrate/nutrient concentrations, these parameters play a big role in the outcomes of many bioprocesses. What was once a mystery is now carefully managed in large-scale bioreactor fermentations with state-of-the-art sensor equipment, ensuring reliable results. However, what often slips under the radar is the need to pay equal attention in smaller-scale experiments, like shake flasks. The success of scaling up relies on getting things right from the start. Bioprocessing calls for adjusting parameters at every step, ensuring a smooth journey from the lab to large-scale production. Therefore, good laboratory practices and techniques that allow technology transfer to the productive sector should be encouraged. After all, the careful monitoring and adept control of key parameters stand as the cornerstone to unlocking the full potential and success of any bioprocessing venture – if it is in bioreactors or shake flasks.
