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Osazone formation was developed by Emil Fischer, [3] who used the reaction as a test to identify monosaccharides. The formation of a pair of hydrazone functionalities involves both oxidation and condensation reactions. [4] Since the reaction requires a free carbonyl group, only "reducing sugars" participate.
An example of a positive Seliwanoff’s test. Seliwanoff’s test is a chemical test which distinguishes between aldose and ketose sugars. If the sugar contains a ketone group, it is a ketose. If a sugar contains an aldehyde group, it is an aldose. This test relies on the principle that, when heated, ketoses are more rapidly dehydrated than ...
The ICUMSA Methods Book [3] contains detailed instructions for analyzing raw, cane, white, beet, molasses, plantation white and specialty sugars. Among these are methods for determination of dry solids content by polarimetry, densimetry and refractometry, color (extinction coefficient at 420 nm), reducing sugars, and the presence of metals such ...
[7] [8] Hydrazone-based coupling methods are used in medical biotechnology to couple drugs to targeted antibodies (see ADC), e.g. antibodies against a certain type of cancer cell. The hydrazone-based bond is stable at neutral pH (in the blood), but is rapidly destroyed in the acidic environment of lysosomes of the cell.
It is often used in place of Fehling's solution to detect the presence of reducing sugars and other reducing substances. [2] Tests that use this reagent are called Benedict's tests. A positive result of Benedict's test is indicated by a color change from clear blue to brick-red with a precipitate.
Phenylhydrazine is used to prepare indoles by the Fischer indole synthesis, which are intermediates in the synthesis of various dyes and pharmaceuticals.. Phenylhydrazine is used to form phenylhydrazones of natural mixtures of simple sugars in order to render the differing sugars easily separable from each other.
Coffee extraction occurs when hot water is poured over coffee grounds, causing desirable compounds such as caffeine, carbohydrates, lipids, melanoidins and acids to be extracted from the grounds. The degree to which extraction occurs depends on a number of factors, such as water temperature, brewing time, grind fineness, and quantity of grounds.
Fischer projection of D-glyceraldehyde. Like most carbohydrates, simple aldoses have the general chemical formula C n (H 2 O) n.Because formaldehyde (n=1) and glycolaldehyde (n=2) are not generally considered to be carbohydrates, [1] the simplest possible aldose is the triose glyceraldehyde, which only contains three carbon atoms.