Carbohydrates lab Flashcards
Starch is isolated from plant sources via ____ since starch is slightly soluble in H2O
selective dissolution
Starch is a good example of a ____.
homoglycan or heteroglycan
homoglycan
What are the two polysaccharides that build up starch?
Amylose & Amylopectin
Among the two polysaccharides that build up starch, which is linear (unbranched)?
Amylose
The linear polysaccharide that builds up starch is connected by ____ glycosidic bonds
α-1,4-glycosidic bonds
Among the two polysaccharides that build up starch, which is branched?
Amylopectin
Amylopectin, similar to the linear polysaccharide that builds up starch via α-1,4-glycosidic bonds, the branching is linked via ____ glycosidic bonds
α-1,6-glycosidic bonds
What saccharide will you isolate from liver?
glycogen
what isolation principle ruptures the membranes of the liver so as to free glycogen?
homogenization
iirc, via boiling ito
what reagent is used to remove the proteins of the liver via precipitation so as to free glycogen?
10% TCA
trichloroacetic acid
what reagent is used to precipitate glycogen from the homogenized sample wherein it occurs via the losing of the H2O shell surrounding the glycogen?
95%EtOH
ethanol
what reagent is used to facilitate the precipitation of glycogen using the principles of salting-out?
NaCl
the human liver composes how many percent of the body’s total mass?
10%
~10%
what polysaccharide is the energy reserve of animals that provides sugar for 24-36 hours?
glycogen
Identify the test based on principle
strong acid to dehydrate monosaccharide to produce furfural or hydroxymethylfurfural. Intermediate furfural derivatives will condense with α-naphthol
Molisch’s test
Identify the test based on principle
formation of complex (complexation) with iodine
iodine test
Identify the test based on principle
Cu2+ reduction; cupric oxide to cuprous oxide in a basic (sodium citrate) medium
CuO –> Cu2O
benedict’s test
Identify the test based on principle
Cu2+ reduction; cupric oxide to cuprous oxide in an acidic (acetic acid) medium
CuO –> Cu2O
barfoed’s test
Identify the test based on principle
Strong acid to dehydrate monosaccharide to produce furfural or hydroxymethylfurfural then condensation with resorcinol
seliwanoff’s test
Identify the test based on principle
Strong acid to dehydrate monosaccharide to produce furfural or hydroxymethylfurfural then condensation with orcinol
bial’s orcinol test
Identify the test based on principle
formyl functional group/prim alcohol oxidation to carboxylic acid by nitric acid
mucic acid test
Identify the test based on principle
formyl group/2ndary alcohol oxidation to carboxylic acid/ketone, respectively, by phenylhydrazine
phenylhydrazine/osazone test
positive result of molisch’s test
purple ring at interphase