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When organisms ferment sugars they usually produce lactic acid as a byproduct. This lactic acid production lowers the pH of the media the bacteria is grown in. The pH indicator changes the media color in response to the decreasing pH from the lactic acid production.
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∙ 15y ago
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How would the pH of the culture medium be influenced by sugar fermentation?
If it ferments a sugar, the pH drops (becomes more acidic) -- lower pH #
HOW IS IT POSSIBLE FOR AN ORGANISM TO BE POSITIVE FOR GLUCOSE USE IN A PHENOL RED TEST BUT NEGATIVE IN THE METHYL RED TEST?
Methyl red differs from Phenolred (which is used in the fermentation test and the MSA plates) in that it is yellow at pH 6.2 and above and red at pH 4.4 and below. Phenol red turns yellow below a pH of 6.8. If you get a positive with methyl red and a negative with phenol red, the pH has to be between 6.7 and 6.1.
Why isn't a pH indicator needed in the lactose broth fermentation tubes?
not sure bro
Is Pseudomonas luteola oxidase positive?
in the absence of glucose or lactose , some bacteria are able to use citrate as only source of carcon. alkaline pH change the bromothymol blue indicator from green to blue. pseudomonas can not ferment the glucose and the lactose so it use the citrate as carbon source.
What are the reactants in animal fermentation?
Pyruvate and NADH because of the different strains and ways of metabolic , the products generated by different sorts are not same in which lactic acid fermentation is divided into 3 types ,the same type of lactic acid fermentation ,abnormal fermentation of lactic acid and bifidobecterium fermentation
What is the purpose of the bromcresol purple in the fermentation tube?
These are both used as pH indicators.
What is the purpose of phenol red or bromcresol purple in fermentation tube?
These are both used as pH indicators.
How would the pH of the culture medium be influenced by sugar fermentation?
If it ferments a sugar, the pH drops (becomes more acidic) -- lower pH #
What chemical an you use to test acids and alkali's?
These substances are called pH indicators.
When using the phenol red carbohydrate broth fermentation test at what pH is the pH indicator yellow?
below 6.8
How indicators works?
pH indicators change their color according to the pH of a solution.
What is the pH level in yeast fermentation?
what is the pH level of yeast?
One way to test pH is to use a strip of paper that has several what-hydronium ions- acids-bases-indicators?
hydronium ions
What is acid-base indicators?
These indicators change the color depending on the pH of the solution.
What is the chemical used to identify changes in pH?
They are called pH indicators.
What can indicators identify?
Indicators are used frequently for testing pH; but many other indicators exist for other compounds or ions.
Why doesn't turps react with pH indicators?
most pH indicators are polar, whereas turps is non-polar so it doesnt mix well
