Starch is a polysaccharide 1.Is starch positive in Bial‘s test？（what color ？） 2.Is starch positive in （Seliwanoff‘s）ketohexoses test？（what color would it be if negative）
Starch is a polysaccharide 1.Is starch positive in Bial‘s test？（what color ？） 2.Is starch positive in （Seliwanoff‘s）ketohexoses test？（what color would it be if negative）
Chapter15: Antibiotic Agents
Section: Chapter Questions
Problem 20RQ
Related questions
Question
Starch is a polysaccharide
1.Is starch positive in Bial‘s test？（what color ？）
2.Is starch positive in （Seliwanoff‘s）ketohexoses test？（what color would it be if negative）
Transcribed Image Text:۸۰۰ сотсиол
tu2. Bial's Test (Distinguish between Pentoses and Hexoses) ibensbb selgrad
To test for pentoses, add 0.5 mL of 1% carbohydrate solution (in water) to 1 mL of
Bial's reagent, (Use a glass Pasteur pipette to add the Bial's reagent: do not use a
mechanical pipettor with concentrated acids) and heat the solution in a boiling
water bath for 2 minutes. A blue-green color indicates pentoses or nucleotides
containing pentoses; a yellow-green color indicates hexoses, and dísaccharides
are yellow.
ceas Yellow Blue
zdrops.
groeps
3. Resorcinol (Seliwanoff's) Test (Ketohexoses) A-hoqs
To test for ketohexoses, add 0.1 mL of a 1% carbohydrate solution in water to 119
mL of the reagent, and heat the solution in a boiling water bath for 5 minutes. A
deep red colored precipitate within 5 minute indicates ketohexoses. Sucrose gives
a positive ketohexose test because of partial hydrolysis to glucose and fructose.
Other sugars give a red color upon prolonged heating.onomonengont
Structure of the
Shu the
neay. Rection..
"unknowns. Why Blue
one sugalwoduct.
н-с-но
1
INV
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps
Recommended textbooks for you
Essentials of Pharmacology for Health Professions
Nursing
ISBN:
9781305441620
Author:
WOODROW
Publisher:
Cengage