AMINO ACIDS (post Lab) Flashcards
(29 cards)
What color in xanthoproteic test indicates a positive result
Yellow to orange color
Color that indicates the presence of aromatic Amino acids (tyrosine, Trytophan, Phenylalanine)
Yellow to orange
The sample lacks aromatic rings, so it does not react with nitric acid in Xanthoproteic test
No color change
What are the proteins that shows positive results because they contain one or more aromatic Amino acids in their structure
Albumin
Casein (gelatin)
Beef
Pork
Three aromatic Amino acids
Tyrosine
Trytophan
Phenylalanine
In ninhydrin test the color of ___ indicates a positive result for free amino acid groupd, which are present in most amino acids and proteins
Purple color
In ninhydrin test this color indicates the presence of IMINO ACID GROUP instead of a free amino group
Yellow color
In ninhydrin test what are the proteins that test positive due to the presence of free amino groups in their peptide chains (same as xanthoproteic test)
Albumin
Casein
Beef
Pork
In ninhydrin test all sample will turn purple except ___ because it does not contain free amino groups (contains Imino group)
Proline
It is used to eliminate the non amino groups in experiment
Ninhydrin test
It is used to determine the presence of TRYPTOPHAN, an amino acid with an indole ring.
Hopkins -cole test
In Hopkins -cole test, when TRYPTOPHAN reacts with GLYOXYLIC ACID in the presence of Concentrated sulfuric acid, a ___/___ color rings form at the interface
Purple
Violet
In Hopkins Cole test only ___ among the amino acids gives a positive result
Trytophan
The only amino acid that will produce an INDOLE RING
Tryptophan
What type of test that Proteins like albumin, casein, beef and pork test positive because they contain tryptophan residues
Hopkins cole test
It is a type of test that detects sulfur containing compounds
Lead acetate test
What color indicates a positive result in lead acetate test, due to the formation of LEAD SULFIDE (PbS)
• Proteins are the same (Albumin, casein, beef, pork)
Black precipitate
It is a type of test that detects PEPTIDE BONDS, which are present in proteins but not in individual amino acids
Biuret test
In biuret test this color indicates a positive result due to the complex formation between copper ions and peptide bonds
Purple color
Only ___,___, ___ and __ give a positive result because they are proteins
- All individuals amino acids gives a negative result (no color change) because they lack peptide bonds
Albumin
Casein
Beef
Pork
The type of test that detects the presence of arginine, which contains a guanidino group.
Sakaguchi test
In sakaguchi test the __ color indicates a positive result
Red
The only amino acid the has a red color and contains guanidino group
Proteins like albumin, casein, beef and pork are positive
Arginine
