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Ch. 7 - The Control of Microbial Growth
Tortora - Microbiology: An Introduction 14th Edition
Tortora14th EditionMicrobiology: An IntroductionISBN: 9780138200398당신이 사용하는 게 아니라요?교과서 변경
7장, 문제 8

The use-dilution values for two disinfectants tested under the same conditions are as follows:
Disinfectant A—1:2
Disinfectant B—1:10,000.
If both disinfectants are designed for the same purpose, which would you select?

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1
Understand the meaning of use-dilution values: A use-dilution value indicates the dilution factor at which a disinfectant is still effective. For example, a use-dilution of 1:2 means the disinfectant is effective when diluted to half its original concentration, while 1:10,000 means it is effective even when diluted 10,000 times.
Compare the two disinfectants based on their use-dilution values: Disinfectant A has a use-dilution of 1:2, meaning it requires a relatively high concentration to be effective. Disinfectant B has a use-dilution of 1:10,000, meaning it remains effective even at a very low concentration.
Interpret the practical implications: A higher dilution factor (like 1:10,000) suggests that less disinfectant is needed to achieve the same antimicrobial effect, which can be more cost-effective and potentially less toxic or corrosive.
Consider other factors that might influence the choice, such as the spectrum of activity, safety, environmental impact, and compatibility with surfaces, but based solely on use-dilution values, the disinfectant effective at higher dilution is generally preferred.
Conclude that, based on the use-dilution values alone, Disinfectant B (1:10,000) would be the better choice because it is effective at a much greater dilution, indicating higher potency or efficiency.

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주요 개념

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Use-Dilution Test

The use-dilution test measures the effectiveness of a disinfectant by determining the highest dilution that still kills a standard number of microbes. A lower dilution ratio means the disinfectant is effective at a stronger concentration, while a higher dilution ratio indicates effectiveness even when highly diluted.
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Disinfectant Potency and Concentration

Disinfectant potency refers to how strong or effective a disinfectant is at killing microbes. A disinfectant effective at a higher dilution (e.g., 1:10,000) is more potent because it requires less concentrated solution to achieve microbial kill compared to one effective only at a lower dilution (e.g., 1:2).
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가이드 코스
04:51
Concentration Gradients and Diffusion

Selection Criteria for Disinfectants

Choosing a disinfectant depends on factors like potency, safety, cost, and intended use. When two disinfectants serve the same purpose, the one effective at a higher dilution is generally preferred due to better efficiency and potential cost savings.
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가이드 코스
03:27
Selective Media
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