Microbial Enrichment Techniques Quiz

The initial step in a fermentation process, where microorganisms with potential industrial applications are identified. The goal is to obtain pure or mixed cultures to carry out desired reactions or produce specific products.

Selection of a microorganism is a balancing act between how productive it is and the cost-effectiveness of the fermentation process.

Major repositories housing diverse microorganisms for research and industrial applications.

These collections offer a cost-effective alternative to isolating microorganisms from the environment, potentially saving time and resources.

The ability of an organism to utilize a specific nutrient or thrive in particular environmental conditions.

The temperature at which a microorganism thrives and exhibits optimal growth rates.

The ability of a microorganism to withstand manipulation and modification in a controlled environment.

The yield or amount of a desired product a microorganism can produce under optimized conditions.

A technique used to isolate and cultivate microorganisms in a controlled environment by continuously feeding fresh medium and removing spent medium.

The rate at which fresh medium is added to a continuous culture system, measured as volume of medium added per unit time.

A state of equilibrium in a continuous culture system where the growth rate of the microorganisms equals the dilution rate, resulting in a constant cell concentration.

The maximum specific growth rate of a microorganism under specific environmental conditions, often limited by a particular substrate concentration.

A method of separating two microorganisms (A and B) in a continuous culture based on their different specific growth rates (µ) at various limiting substrate concentrations.

A method of preserving microorganisms by storing them at low temperatures (refrigerator, freezer) to slow down their metabolic activity and prevent cell death.

Solid media (agar plates) used to isolate individual colonies of microorganisms based on their specific biological activity, usually involving selective media that favor the growth of specific enzyme producers.

The maintenance of the viability, purity, and desired characteristics of industrially important microorganisms over time.

A technique used to increase the number of a specific microorganism in a mixed population by providing favorable conditions, like specific nutrients or inhibitors, that promote the growth of the desired organism while inhibiting others.

A method in which the desired microbe is encouraged to grow by providing specific conditions that favor its growth, while suppressing others.

A problem in batch enrichment where conditions that initially favor the desired microbe may change due to waste products or interactions between organisms, allowing undesired microbes to grow.

A technique to overcome the problem of changes in selective force by repeatedly transferring a small amount of the enriched culture to fresh medium with the same selective conditions, ensuring the desired microbe remains dominant.

The time at which subculturing should occur to maintain the dominance of the desired microbe in a batch enrichment technique.

A measure of the rate at which a microbe grows and divides. It helps to understand how fast a particular microbe can multiply.

A device used to maintain a constant environment for microbial growth, allowing consistent cell populations in the exponential phase for extended periods.

Microbes that can continue to grow and produce enzymes even when the substrate concentration is low.

Microbes that naturally produce enzymes without needing an inducer to trigger the process.

The process of introducing mutations to create new genetic variations in microbial cells.

The process of combining genetic material from different sources to create new combinations.

Selecting microbial strains that are resistant to infections, produce less foam, tolerate low oxygen levels, or have other desirable characteristics.

A method of preserving microorganisms by suspending them in a sterile solution, typically water or glycerol, and storing them at low temperatures (4°C).

A method of preserving microorganisms by suspending cells in a solution containing glycerol (15-30%) and storing them at very low temperatures (-80°C).

A method of preserving microorganisms by storing them at extremely low temperatures (-150°C to -196°C) in liquid nitrogen. Cryoprotective agents like glycerol are used to protect cells during freezing.

A process of preserving microorganisms by removing water from a frozen sample through sublimation, which means the water changes directly from ice to vapor without becoming liquid.

The first stage of lyophilization, where the sample is cooled down to a predetermined temperature, typically below its freezing point, to freeze the water in the sample.

The second stage of lyophilization, where ice is removed from the frozen sample by lowering the pressure and increasing the temperature, causing the ice to sublime directly into vapor.

The final stage of lyophilization, where any remaining moisture is removed from the sample by lowering the pressure and increasing the temperature, ensuring the sample is completely dried.

A protective medium used to prevent the damage of microorganisms during lyophilization. This medium can consist of substances like skimmed milk, sucrose, or serum.

The process of increasing the yield and productivity of microbial strains by optimizing their growth conditions and medium composition. This approach aims to maximize the organism's potential for producing a desired product.

A method of improving microbial strains by selecting naturally occurring variants that exhibit superior traits. This approach exploits genetic diversity within the microbial population.

A method used to improve microbial strains by inducing genetic changes that enhance their desired characteristics. This involves exposing the microbes to agents or conditions that trigger mutations.

A method of improving microbial strains by introducing new genetic material from other organisms into the target microbe's genome. This allows for the transfer of desirable traits, leading to enhanced productivity.

A process of isolating individual microbial cells from a colony, often using solidified media, to obtain a pure culture that is genetically homogeneous. This allows for the selection of stable and superior producers.