All Questions
Tagged with biochemistry carbohydrates
47
questions
6
votes
2
answers
159
views
What does ‘D’ in GADP (glyceraldehyde 3-phosphate) stand for?
Wikipedia says glyceraldehyde-3-phosphate can be abbreviated as G3P, GA3P, GADP, GAP, TP, GALP or PGAL, and many resources seem to use GADP as its abbreviation.
I have no idea where ‘D’ came from. ...
- 129
0
votes
0
answers
26
views
Why can't the fructose monomer in sucrose be α-fructose?
In all academic sources, sucrose is identified as α−glucose (1-->2) β−fructose. However, I cannot find any explanation anywhere as to why the fructose monomer has to be in the β configuration. ...
- 11
0
votes
0
answers
23
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Bioplastic from starch
I am doing research in bioplastic from starch. I have tried many quantities and concentrations of starch, vinegar and glycerol at different temperatures. But I am unable to get a certain result of the ...
0
votes
0
answers
254
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Why does glucose react with hydroxyl amine and HCN but doesn't give Schiff's test or react with NaHSO3?
I can't understand this because if there isn't a free CHO group then it also shouldn't react with NH2OH and HCN.
On the same note can anyone also explain why pentaacetate of glucose not react with ...
- 19
-1
votes
2
answers
2k
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Are Starch, Amylose and, Amylopectin reducing sugars?
Amylose and Amylopectin;
As per the information I've learnt, Amylose is considered a reducing sugar but Amylopectin is not because Amylose has a free "reducing end" which Amylopectin lacks, ...
1
vote
2
answers
283
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How does industry separate glucose from fructose using liquid chromatography when producing high-fructose corn syrup?
Can someone explain how the separation of glucose and fructose is achieved using liquid chromatography in the industrial production of high-fructose corn syrup?
I've seen references to ion-exchange ...
- 121
0
votes
1
answer
405
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Does changes in pH affects cyclic form of glucose in water solution?
Glucose in water solution is mainly in cyclic form. Both base and acid can catalize formation of hemiacetal, but in distinct mechanisms. I found information that monosacharides eg. glucose exist ...
10
votes
1
answer
1k
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Can sugars dissolve in liquid ammonia?
Can monosaccharides and disaccharides dissolve in liquid ammonia due to hydrogen bond formation?
My rationale is that these sugars may be able to form hydrogen bond with ammonia ($\ce{NH3}$).
- 109
0
votes
0
answers
2k
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Haworth structures of sucrose and lactose
The haworth structures of lactose and sucrose is
My question is regarding the glyosidic linkage, in lactose it is represented as a zig zag and in sucrose it is a "V". What does that mean. ...
user95393
2
votes
0
answers
212
views
Do enzymes that digest ᴅ-glucose react with ʟ-glucose?
ᴅ-Glucose is common in nature and ʟ-glucose is synthesized in the lab.
I know that humans can't use ʟ-glucose in their aerobic pathways because it doesn't match the active site of the enzyme, but why ...
- 29
7
votes
2
answers
3k
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Oxidation of hydroxyl groups of glucose
In all oxidation reactions of glucose, it seems that the aldehyde group alone gets oxidised and none of the hydroxyl groups. In one reaction with nitric acid, the aldehyde group and the terminal ...
- 103
1
vote
0
answers
449
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Where does the beta notation come from in the alpha 1,2 beta glycosidic bond (in sucrose)? [duplicate]
I am confused as to where the beta is coming from (in the alpha-1,2-beta glycosidic bond in sucrose). I understand that the alpha is from the anomeric carbon of the glucose, but I don't see how the ...
8
votes
1
answer
2k
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Does cooling a potato change the nature of its carbohydrates?
A talk-show guest of Joe Rogan claimed that cooling a potato after cooking creates "resistant starch" that's better for human consumption
https://www.youtube.com/watch?v=niwqfwA2Lb8
The ...
- 519
3
votes
1
answer
3k
views
How are glycosidic linkages formed?
Consider glycosidic linkages in disaccharides.
I know a condensation reaction occurs, with the loss of water.
But which OH is lost? The O in the linkage belongs to which monosaccharide?
Example: ...
- 776
5
votes
2
answers
3k
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How does existence of alpha and beta form of glucose prove that it exists as a cyclic structure
My book says that
Glucose is found to exist in two different crystalline forms which are
named as $\alpha$ and $\beta$.
Next it says that
This behaviour could not be explained by the open ...
- 305