Fermentor - Part 1

Summary

This transcript outlines the detailed process of preparing a fermentation medium for an experiment. It involves steps like measuring and mixing specific ingredients such as peptone, yeast, and glucose with distilled water, adjusting pH to 4.5 with sulfuric acid, and calibrating the pH meter. After preparing the solution, the mixture is transferred to a fermentor, followed by autoclaving the vessel and solutions for sterilization. The procedure also includes steps for preventing contamination, calibrating probes, and ensuring proper setup of the fermentor in a lab environment. Each step emphasizes careful handling and precise measurements for optimal results.

Takeaways

• 😀 Begin by stirring 2,000 mL of distilled water and add 60 g of peptone and 30 g of yeast extract to the flask.
• 😀 Be cautious as peptone absorbs water and can become sticky on the flask surface.
• 😀 Rinse the sides of the flask with an additional 500 mL of distilled water to ensure proper mixing.
• 😀 Adjust the pH of the solution to 4.5 by adding 10% sulfuric acid dropwise while stirring.
• 😀 Remove the head plate, empty the solution into the fermentor, and add two drops of antifoam.
• 😀 Prepare an optical density blank by dissolving 6 g of peptone and 3 g of yeast extract in 300 mL of distilled water.
• 😀 Slowly dissolve 50 g of glucose in 200 mL of distilled water on a hot plate, then dilute the solution to 450 mL.
• 😀 Apply a lubricant around the glass vessel and secure the head plate with metal rings before tightening the bolts.
• 😀 Calibrate the pH probe with a pH 7 buffer solution and adjust the span with an FL buffer solution.
• 😀 Carefully load the fermentor and solutions into the autoclave, set the cycle for 45 minutes at 121°C, and ensure proper safety measures during autoclaving.

Q & A

What is the purpose of stirring the 2,000 mL of distilled water in the script?

The stirring of 2,000 mL of distilled water ensures that the water is well-mixed before the addition of other ingredients like peptone and yeast extract, helping them dissolve more easily.

Why is it important to be cautious when adding peptone to the flask?

Peptone absorbs water and can become sticky on surfaces, making it difficult to mix. This requires careful addition and proper mixing to avoid clumping.

What is the purpose of adjusting the pH of the solution to 4.5?

Adjusting the pH to 4.5 ensures that the medium is at the optimal pH for microbial growth or fermentation processes, which can be sensitive to pH levels.

Why is sulfuric acid added dropwise to adjust the pH?

Sulfuric acid is added dropwise to carefully control the pH change, as adding too much at once could overshoot the target pH and cause instability.

What role does antifoam play in the process?

Antifoam is added to prevent excessive foam formation during fermentation, which could cause problems like clogging or difficulty in maintaining proper liquid levels.

Why is the optical density blank solution prepared, and what does it consist of?

The optical density blank solution is prepared to calibrate equipment used for measuring optical density in later steps. It consists of peptone and yeast extract dissolved in distilled water.

What is the significance of diluting glucose solution to 450 mL with distilled water?

Diluting the glucose solution ensures that the final concentration is appropriate for the fermentation process, allowing for optimal growth and metabolism of the microorganisms.

Why must the glass vessel be lubricated before use?

The lubricant around the top surface of the glass vessel helps create a tight seal, preventing any leaks or contamination during the fermentation process.

What is the purpose of autoclaving the fermenter and solutions?

Autoclaving sterilizes the fermenter and solutions by using high heat and pressure, killing any microorganisms that might cause contamination during the fermentation process.

What is the role of the pH probe during calibration and the fermentation process?

The pH probe is used to measure and calibrate the pH of the solution. It ensures that the medium maintains the correct pH throughout the fermentation process for optimal microbial activity.