What to use to distinguish between protein and sucrose

If you are doing a biology problem, use biuret reagent (NaOH solution at a concentration of a solution with a concentration of solution) to check for protein, and a film reagent (NaOH solution with a concentration of NaOH solution, CuSO4 solution at a concentration of CuSO4) to check for glucose (a product of sucrose hydrolysis).

If you are doing a chemistry problem, use Hno3 to check whether there is a protein, and the protein does not react with sucrose when Hno3 turns yellow (nitrification). Or you can add a strong acid or base to the AQ and add metal ions to it, which will solidify the protein. Check for sucrose:

Add dilute sulfuric acid to AQ to hydrolyze sucrose to produce glucose, at this time, there are two reagents to choose from: 1 is the film reagent I mentioned above, and 2 is to use a silver mirror reaction to test whether there is glucose.

1) Identify with concentrated nitric acid, take samples separately, add an appropriate amount of concentrated nitric acid to the sample, yellowing is protein solution (flathroprotein reaction), and no obvious phenomenon is sucrose.

2）.Identification with dilute sulfuric acid: samples are taken separately, an appropriate amount of dilute sulfuric acid is added to the sample and heated.

Using the principle of reducing sugar (glucose) produced by sucrose hydrolysis, excess sodium hydroxide is added, and the newly prepared copper hydroxide is reacted under alkaline conditions.

Sucrose is the most widely distributed non-reducing disaccharide in nature. It is found in many plants and is most abundant in sugar cane and sweeteners, hence the name. Pure sucrose is a colorless crystal that is easily soluble in water and sweeter than glucose and maltose, but not if the sugar is sweet.

Sucrose is formed by the condensation of a glucose molecule and a fructose molecule and the loss of a water molecule. The fructose molecule belongs to non-reducing aldehydes, and the glucose molecule belongs to non-reducing ketones. Under the action of acid or sucrase, sucrose is hydrolyzed to produce equal amounts of glucose and fructose.

Therefore, its hydrolysate is reducible.

Many people believe that alternative sweeteners such as honey, brown sugar, or molasses are healthier than sucrose. However, this is not necessarily true. Sugar is a simple carbohydrate that your body uses for energy.

1.Boost energy.

Your body's main energy** is a simple sugar called "glucose", which comes from the breakdown of sugar. You'll often find liter sugars in fruits, dairy products, and cereals. But your body processes sucrose in the same way that it processes sugar in any other food.

It is broken down into two simple sugars at the same time – fructose and glucose. It can provide energy for the body, replenish muscle glycogen in time, and play a very obvious role in relieving muscle fatigue and restoring physical strength.

2.Moisturizing and dry.

Because from the perspective of traditional Chinese medicine food therapy, the white sucrose enters the lung meridian, for people with cough, phlegm, and asthma caused by lung dryness, proper consumption of sucrose has a good effect of moisturizing dryness, relieving cough and asthma.

3.Relieves abdominal pain.

For people with moderate and abdominal pain and bloating, eating sucrose appropriately has a good effect of relieving moderate and acute and relieving abdominal pain.

4.Control blood sugar levels.

When you consume more glucose than your body needs for energy, the excess glucose is stored in fat cells and the liver in the form of glycogen. This process helps your body's blood sugar levels return to normal.

This energy store is healthy as long as you don't eat more calories than you burn – like having a big gas tank in your car so you don't have to refuel as often. It allows your body to function without having to eat as often.

5.Boosts hormones.

Sucrose triggers the body's production of serotonin, a hormone that puts you in a good mood. A drop in serotonin levels in your body is the reason why you crave sugar, especially if you're tired or unhappy. When you eat sugary foods, you get a mood boost from serotonin.

The appearance of sucrose is dry and loose, white, shiny, and there should be no obvious black spots on the white paper, and the particles are divided into coarse, large, medium and fine grains, the particles are uniform, the grains are shining, and the contours are clear; The white sugar has fine grains, evenly covering the rotten celery, the color is white, and it is more soluble in water than white sugar, which is suitable for general drinks, snacks and other sugar foods; Red granulated sugar is crystalline or powdery, dry and loose, no agglomeration, no clumping, no impurities, its aqueous solution is clear, no precipitation, no suspended solids, Hongbi color has reddish-brown, green-brown, yellow-brown, red, golden, light yellow, jujube red and other historical groups; Rock sugar is uniformly white or yellow, translucent, with crystalline luster, and no obvious impurities.

Distinguish between glucose, fructose, sucrose, and starch.

The easiest way to distinguish glucose, fructose, sucrose, and starch is to talk about color in a whisper.

First of all, an appropriate amount of iodine solution is added to each of these four sugars, only the starch turns blue, and the other three sugars do not change color.

Then, in addition to starch, an appropriate amount of hydrochloric acid and resorcinol were added to the three kinds of sugar, glucose was light red, fructose was red, and sucrose did not change color, so that sucrose could be identified.

Then add a few drops of water to glucose and fructose respectively, because the grape cloud sugar has the reducing property and the bromine water fades, fructose has no reducing property, can not make the bromine water fade, so that the purpose of distinguishing these two sugars can be achieved.

Since glucose, maltose, and fructose are all reducing sugars, and sucrose is a non-reducing sugar, the three reducing sugars with characteristic reactions can be identified and classified with Feilin reagent, Ban's reagent, and silver ammonia solution, and sucrose without characteristic reactions.

Identification of glucose, maltose, and fructose. Two methods:

1) The aqueous solution of these three substances is added to the clear lime water respectively, and the white precipitate is fructose, because fructose will combine with Ca(OH)2 to form insoluble substances, while the other two sugars do not have this phenomenon.

2) Identification with bromine water, glucose and maltose can fade bromine water and react with bromine water to generate corresponding sugar acid, while fructose is ketose (isomerization reaction can only occur under alkaline conditions to form aldose sugar), which cannot be oxidized by bromine water under acidic conditions, so bromine water cannot be faded.

There are two methods for the identification of glucose and maltose:

1) The same mass of glucose and maltose are heated with H2 under the catalysis of nickel respectively, and the more H2 consumed is glucose, and the less is maltose.

2) Glucose and maltose react with phenylhydrazine to form glycohydrate, the faster is glucose, and the slower is maltose.

, glucose: Filin reagent. The water bath is heated with a brick-red precipitate.

Fructose: This is inseparable from glucose.

Sucrose: concentrated sulfuric acid. will char.

Maltose: plus filin reagent. No response. Because it needs to be hydrolyzed with sulfuric acid to react with Filin reagent, starch: iodized water. The starch turns blue when exposed to iodine.

The teacher said that mastery is not required at the high school level.

To distinguish fructose and glucose, you can use a mass plister.

Because fructose is a polyhydroxyketone and glucose is a polyhydroxyaldehyde.

The silver mirror reaction should be under alkaline conditions.

Whereas, ketones turn into aldehydes under alkaline conditions.

1. Different properties: glucose.

Starch can be used as raw material, through hydrochloric acid or dilute sulfuric acid.

Hydrolyzed. It can also be prepared by starch asis as a raw material under the action of starch saccharification enzyme. Cane sugar.

The specific gravity of the solution varies depending on the concentration and temperature. The specific rotation of sucrose is + to +.

2. Different characteristics: sucrose has a sweet taste, no smell, and is easily soluble in water and glycerin.

Slightly soluble in alcohol. Pure glucose is colorless crystals, has a sweet taste, but the sweetness is not as sweet as sucrose, and it is easily soluble in water.

3. Chemical properties.

Different: It is easy to decompose when heated under alkaline conditions. It should be stored tightly closed. After oral administration, it is quickly absorbed, and after entering the human body, it is used by tissues. Sucrose and sucrose solutions will produce a variety of different chemical reactions under the action of heat, acid, alkali, yeast, etc.

The result of the reaction not only directly causes the loss of sucrose, but also produces some substances that are harmful to sugar production.

The identification method of glucose copy is not only to know that it is a multiple hydroxyl compound, but also to know that it also contains aldehyde groups, so generally in middle school, the identification of it is within a certain range.

Fructose is also a reduced monosaccharide, so the two can not be distinguished by silver mirror reaction, and the difference between fructose and glucose is that fructose will produce basic fructose calcium precipitation under the action of lime water, and the precipitate will be filtered out of distilled water, and the CO2 precipitation will be converted into CaCO3, and the fructose will be restored.

Glucose, fructose, and maltose are also original sugars that can be tested with Feilin's reagent

There is a brick-red precipitate generated within.

The starch is tested with iodine The phenomenon is that it turns blue.

The remaining glycogen and sucrose are added to the catalytic enzyme and then used in the first method, and the brick-red precipitate is sucrose (hydrolyzed with fructose and glucose).

It's glycogen.

Because of glycoproteins.

specificity. The specificity of the structure and arrangement of the molecule. Others, proteins are mostly enzymes, receptors, channels, carriers, lipids.

It is a basic structure, and it is not suitable for identification. Because it's all the same.

Receptors made by proteins refer to the receptors of hormones.

Glycoproteins, on the other hand, generally bind to objects that have complementary structures, such as antigens and antibodies.

That's right, in the first volume of high school biology, the original words are.

in the cell membrane. On the surface, there is a layer of glycoprotein formed by the combination of proteins and polysaccharides on the cell membrane, which is called glycocoat. It has an important function in cellular life activities. For example, the digestive tract and respiratory tract.

Glycoproteins on the surface of upper epidermal cells have protective and lubricating effects, and sugars are closely related to cell surface recognition. It has been found that the recognition of glycoproteins on the surface of animal cells is like the language and writing used to communicate between cells, or between cells and other macromolecules".

It's authoritative.

Experimental Procedure:1Take a small amount of solution and scatter it in 2 tubes.

2.Add an equal amount of silver ammonia solution (or newly made copper hydroxide solution) to the 2 test tubes in a water bath and heat. Observe the inner wall of the test tube.

experimental phenomena and results; If there is a silver mirror (or brick-red precipitate) on the inner wall of the test tube.

then it is a glucose solution.

On the contrary, if there is no obvious phenomenon, it is a local sucrose solution.

Explanation: Glucose contains aldehyde groups, so it can react with silver ammonia solution and freshly made copper hydroxide to produce silver mirror and brick-red precipitate.

Sucrose does not contain aldehyde groups, but contains ketone groups, which cannot make silver ammonia solution or newly made copper hydroxide produce silver mirror or brick red precipitate.

The original finch digs the answer. Hope.

Just taste the taste, and the sweet taste is cane sugar.