Culturing: Conditions

Introduction

• Culturing micro-organisms involves controlling specific conditions to promote growth and prevent contamination.
• Conditions include temperature, oxygen levels, pH, nutrients in the growth media, and maintaining sterility.

Controlled Conditions

• Temperature: Maintaining an optimal temperature is crucial for microbial growth, as different species thrive at specific temperature ranges.
• Oxygen Levels: Some micro-organisms require oxygen for respiration, while others thrive in oxygen-free environments.
• pH: pH levels can be adjusted using acids, alkalis, or buffer solutions to create a suitable environment for microbial growth.
• Nutrients: Growth media should provide essential nutrients required by the micro-organisms.
• Sterility: Ensuring sterility is vital to prevent contamination by other micro-organisms.

Contamination Prevention

• Heat Sterilisation: Autoclaves use high temperatures to kill microbes and sterilise equipment.
• Radiation Sterilisation: Electromagnetic radiation, such as UV waves, can be employed to eliminate micro-organisms.
• Chemicals: Disinfectants and antiseptics are used to maintain sterile conditions.

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Culturing: Conditions

Tailored Growth Conditions

• Microbial growth conditions vary based on the species being cultured.
• Oxygen supply or absence can be controlled to accommodate aerobic and anaerobic microbes.
• Stirring or aeration is used to ensure an even distribution of oxygen in the growth medium.

Importance of Sterile Conditions

• Sterile conditions in fermenters reduce competition among micro-organisms and minimise the risk of product spoilage.