Search results
Results from the WOW.Com Content Network
Bromothymol blue (also known as bromothymol sulfone phthalein and BTB) is a pH indicator. It is mostly used in applications that require measuring substances that would have a relatively neutral pH (near 7). A common use is for measuring the presence of carbonic acid in a liquid.
If the tube with oil doesn't turn yellow, but the open tube does turn yellow, then the bacterium is oxidizing glucose. If the tube with mineral oil doesn't change, and the open tube turns blue, then the organism neither ferments, nor oxidizes glucose. Instead it oxidizes peptones, which liberates ammonia, turning the indicator blue.
Bacteria are inoculated on a medium containing sodium citrate and a pH indicator such as bromothymol blue. The medium also contains inorganic ammonium salts, which are utilized as sole source of nitrogen. Use of citrate involves the enzyme citrate lyase, which breaks down citrate to oxaloacetate and acetate.
Solution: The main components of a universal indicator, in the form of a solution, are thymol blue, methyl red, bromothymol blue, and phenolphthalein. This mixture is important because each component loses or gains protons depending upon the acidity or alkalinity of the solution being tested. It is beneficial to use this type of universal ...
The observed spectrum (green) is the sum of the spectra of HA (gold) and of A − (blue), weighted for the concentration of the two species. When a single indicator is used, this method is limited to measurements in the pH range p K a ± 1, but this range can be extended by using mixtures of two or more indicators.
You can even whip up your own refreshing lower-sugar drinks, like our Raspberry Ginger Lime Seltzer, Cucumber-Mint Spritzer or Grapefruit Soda recipes. 2. Sweetened or High-Fat Coffee Drinks.
Bowen also predicts that other natural options may become more popular, including minerals such as calcium carbonate (white) and iron oxides (red, brown and black), fruit and vegetable extracts ...
The increase in pH then causes color change in the bromothymol blue indicator, turning it blue. Under neutral conditions the medium remains a green color. The color change to blue is useful because growth on Simmons' citrate agar is often limited and would be hard to observe if it were not for the color change.