SIMPLE TEST PROTEIN

This biuret test is carried out with the aim of determining the presence of compounds containing acid amide groups. Biuret reaction is a test carried out to determine peptide bonds. This reaction is positive (purple) for substances containing 2 or more peptide bonds.
Biuret reactions are a common color reaction for peptide groups (-CO-NH-) and proteins. A positive reaction is characterized by the formation of a purple color due to the formation of complex compounds between Cu2 + and N from peptide bond molecules. The amount of amino acids bound to the peptide bonds influences the color of this reaction. Compounds with dipeptides give a blue color, purple tripeptides and tetrapeptides and complex peptides give a red color. Biuret is produced by heating urea at about 180 oC in an alkaline solution. Biuret gives violet color with CuSO4. This reaction is called a biuret reaction, the possibility of the formation of Cu2 + with CO and NH groups from the peptide chain in an alkaline atmosphere. Dipeptides and amino acids (except histidine, serine and threonine) do not provide this test. Some proteins that have the -CS-NH-, -CH-NH group in their molecules also provide positive color tests with biuret.
Qualitative protein tests were performed on three samples namely, chicken egg albumen, duck egg albumen, and gelatin. Based on the biuret testing method, this test is carried out to determine the presence of protein in a material.
In the process the protein is made alkaline with NaOH then aqueous solution of CuSO4 is added. This test is carried out to show the presence of compounds containing acid amide groups
Thus the biuret test not only for protein but other substances such as biuret or melonamide also give a positive reaction that is marked by the emergence of red-violet or blue-violet.

[@unknownboy4162]

Proteinnya bisa di makan bang?

[@jangantontonofficial]

Yg ini nggak lah bg