10 response of the skeletal system to exercise; osteoporosis and fitness new
3 simple and complex carbohydrates lec 3
1. Principle of Biochemistry
3-Simple and Complex
Carbohydrates
Course code: HFB324
Credit hours: 3 hours
Dr. Siham Gritly
Dr. Siham Gritly 1
2. Terms should be learned
vocabulary
• Carbohydrate; generic name for simple and
complex sugars; chemically carbohydrates are
polyhydroxyl aldehydes or polyhydroxyl ketones
• Aldose; sugar containing an aldehyde functional
group
• Ketose; sugar containing a ketone functional group
• anomeric carbon; the carbon atom in a cyclic
monosaccharide which, in the linear monosaccharide,
holds the aldehyde or ketone functional group
Dr. Siham Gritly 2
3. vocabulary
• Asymmetric carbon; carbon atoms attached to four different atoms or
groups or chiral carbon
• Chiral carbon; atoms have four different atoms or groups covalently attached
to them
-linked sugars; refers to;
(a) the geometry of the glycosidic bond (α = opposite side of the sugar ring from
the free CH2OH; β = same side),
(b) which carbon on ring A is linked to which carbon on ring B.
• Stereoismers; are compounds having two or more chiral carbons that have the
same four groups attached to carbon atoms but are not mirror images to each
other
• D-sugar; the stereoisomeric form of monosaccharide. One of a set of isomers
whose molecules have the same atoms bonded to each other but differ in the
way these atoms are arranged in space.
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4. vocabulary
• Furanose; cyclic form of glucose monosaccharide whose
structure is a five-membered ring
• Pyranose; cyclic form of glucose; monosaccharide in a six-
membered ring form
• glycosidic bond; ether bond joining two monosaccharides
• hemiacetal or hemiketal; cyclic conformation of simple
carbohydrates; formed by reaction of the aldehyde (or ketone)
and one of the hydroxyls on the carbohydrate
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5. vocabulary
• Monosaccharides. "Simple sugars" with the formula (C H2O)n. The word
carbohydrate refers to the fact that this class of molecules consists of
hydrates of carbon.
• Disaccharides; "Simple sugars" contain two monosaccharides units
attached to one another through acetal bonds or as known glycosidic bonds
• Oligosaccharides. complex sugar Polymeric molecule of sugar
comprising 2-10 covalently linked monosaccharide units. Often
found conjugated to other classes of biomolecules including lipids
and proteins.
• Polysaccharides. complex sugar Larger polymers of simple sugars.
On the order of hundreds to thousands of monosaccharide units as
linear or branched polymers
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6. vocabulary
• Aldehyde ; Any of a class of highly reactive organic chemical
compounds obtained by oxidation of primary alcohols,
characterized by the common group CHO, and used in the
manufacture of dyes, and organic acids.
• Aldehydes are oxidized to carboxylic acids and take part in
many addition reactions
• ketone Any of a class of organic compounds, such as acetone,
having a carbonyl group linked to a carbon atom in each of
two hydrocarbon radicals and having the general formula
R(CO)R ,
• Ketones don't have that hydrogen atom and are resistant to
oxidation. They are only oxidised by powerful oxidising
agents which have the ability to break carbon-carbon bonds.
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8. Carbohydrates
are polyhydroxy aldehydes or ketones (Constructed
from the atoms of carbon, oxygen and hydrogen)
• In aldehydes (aldose) the carbonyl is bonded to
one carbon and one hydrogen and are located at
the ends of carbon chains. Formula H-
(CHOH)x(C=O)-
• In ketones (Ketoses) carbonyl group (C= O) is
bonded to two carbons within a carbon
skeleton
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9. In aldehydes (aldose) the carbonyl is bonded to one
carbon and one hydrogen and are located at the ends of
carbon chains. H-(CHOH)x(C=O)- easily oxidized
In ketones (ketose) carbonyl group (C= O) is bonded to
two carbons within a carbon skeleton no hydrogen atom
H H
| |
H—C—C—C—H
| " |
H O H
H H H
| | |
H—C—C—C=O
| |
H H Glycerildyhide
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10. • The major carbohydrates found in the body
are structurally related to the;-
• 1-aldotriose glyceraldehyde
• 2-ketotriose dihydroxyacetone.
• All carbohydrates contain at least one
asymmetrical (chiral) carbon and are,
therefore, optically active.
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11. Aldotriose and ketotriose
glyceraldehyde is especially
important because the more complex monosaccharides may
be considered to be derived from them
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13. Monosaccharides
• The common monosaccharides (hexoses) of
living organisms are:
• (glucose, galactose, fructose) C₆H₁₂O₆
• (ribose, deoxyribose, ribulose, xylose) 5-
carbon pentoses (C5H10O4).
• Contain 3-7 carbon atoms.(trioses, tetroses,
pentoses, hexoses and heptoses)
• Contain hydroxyl groups -OH
• Carbonyl group C=O
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14. • The 5-carbon monosaccharide ribose is an
important component of;-
• - coenzymes (e.g., ATP, FAD, NAD)
• - the backbone of the genetic molecule RNA
• Deoxyribose which is a component of DNA
•
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15. glucose is the most important
monosaccharide
Ketoses contain a ketone
Aldoses contain an aldehyde (C=O) functional group
(-CHO ) functional groupat usually at C #2. e.g. fructose
one end e.g. glucose
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16. the nomenclature and functional group for
monosaccharides
Number of Carbons
Aldose
(Generic Ketone Functional
Functional Relevant examples
monosaccharide Group
Group
name)
3 Ketotriose Glyceraldehyde,
Aldotriose
(Triose) Triulose Dihydroxyacetone
4 Ketotetrose
Aldotetrose Erythrose
(Tetrose) Tetrulose
5 Ketopentose Ribose, Ribulose,
Aldopentose
(Pentose) Pentulose Xylulose
6 Ketohexose Glucose, Galactose,
Aldohexose
(Hexose) Hexulose Mannose, Fructose
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18. Stereochemistry
Isomerism
• Stereochemistry deals with arrangements of atoms in
molecules and the effects of these arrangements on the
chemical and physical properties of substances
• Isomerism are compound have the same structural formula
but differ in configuration
• The presence of asymmetric carbon or chiral (carbon atoms
attached to four different atoms or group) allows the
formation of isomer
• Different groups are attached it is easy to move any two or
groups of atoms to other position and rotate the new
structure
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19. D and L isomerism
• Organic substances usually are optically active
• The presence of asymmetric carbon atoms give optical
activity on the compound
• If Plane-polarized light is passed through a solution of
the substances, ;-the plane of light is rotated to
• - the right (dextrorotary substances)
• -or to the left (for levorotatory )
• expressed as
• *dextrorotary (D)
• *levorotary (L)
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20. • The direction and extend of the rotation of a
particular compound depend on;
• -concentration of the substances
• -temperature
• -wave of the light
• Enzyme function specify the particular
configuration such as L-glutamate
dehydrogenase
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21. The majority of saccharides in nature have
the "D" isomer
Fischer projection
Haworth
Projection of β-
D-Glucose
The orientation of the –H and –OH groups around the carbon
atom adjacent to terminal alcohol carbon (CH2OH) carbon 5
determine whether the sugar is D or L isomer
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22. Haworth Projection of α- and β D-Glucose
In α-D-glucose the anomeric carbon’s –OH group is on the
right. In the Haworth projection of α-D-glucose illustrated
below the –OH group points down and β D glucose OH
pointed up.
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23. Cyclic Fischer Projection of α-D-Glucose
In cyclic structure or Fisher projection the anomeric
hydroxyl are positioned to right resulting in alpha
configuration
Cyclic Fischer Projection of α-D-
Glucose
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24. Ring and chair configuration of glucose
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25. aldose-ketose isomerism
• The carbonyl group of the keto or aldose
functional group is considered to be closest to
the "start" of the carbon chain.
• The carbon thus identified as the "first"
carbon in the chain is carbon #1. The
remaining carbons are numbered sequentially.
• In Fischer Projections, the "D" isomer will
have the hydroxyl (-OH) functional group
located on the right-hand side of the chiral C.
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26. Fischer projection of glyceraldehyde Aldotriose
D,L designation refers to the configuration the
highest-numbered asymmetric center
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28. • aldotetroses:
– Carbon 1 is at the end closest to the aldehyde carbonyl
– Carbon 3 is the highest numbered carbon that is chiral
(carbon 4 is not chiral because it contains two
hydrogens)
– The "D" or "L" nomenclature therefore refers to the
chirality of carabon 3. The "D" form has the OH group
on the right-hand side of carbon 3; the "L" form has
the OH group on the left-hand side.
– Carbon 2 is chiral, and the different isomers of this
aldotetrose are indicated by different common names
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30. ketopentoses
• Carbon 1 is the end closest to the keto group
• Carbon 4 is the highest chiral carbon and
determines the "L" or "D" isomer
nomenclature for the saccharide
• Carbon 3 is also chiral, and its chirality
determines the common name
• Carbon 2 is not chiral, neither is carbon 1, or
carbon 5.
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31. Cyclic monsaccharide structures and
anomeric forms
α and β anomers
• Ring structure of CHO
• In solution the molecules cyclize by a reaction between
carbonyl group and hydroxyl group
• If the sugar contain an aldehyde it is called hemiacetal
• If the sugar contain a keto group it is called hemiketal
• In cyclic structure or Fisher projection the anomeric
hydroxyl are positioned to right resulting in alpha
configuration
• If the anomeric hydroxyl are positioned to left the
structure would be in beta configuration
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32. • The resulting chirality of the aldehyde carbon
(or keto carbon in ketoses) in the cyclic
structure can be either the α- or β- form. This
carbon is termed the anomeric carbon, and
the α - and β - forms are anomers.
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33. pyranose and furanose ring structures
• "Pyranose" is used to refer to the pyran ring
structure (6-membered ring with 5 carbons and 1
oxygen)
Cyclic sugars that contain a six membered ring
are called "pyranoses
• For five membered rings (four carbons and 1
oxygen) the structure is a furanose ring.
Cyclization is reversible
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34. Cyclic form of glucose is a pyranose
Cyclic form of fructose is a furanose
• The pyranose ring is formed by the reaction of
the hydroxyl group on carbon 5 (C-5) of a sugar
with the aldehyde at carbon 1.
• This forms an intramolecular hemiacetal.
• If reaction is between the C-4 hydroxyl and the
aldehyde, a furanose is formed hemiketal.
• The pyranose form is more stable than the
furanose form,
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35. • glucose forms an intra-molecular hemiacetal
by reaction of the aldehyde on C1 with the
hydroxyl on C5, forming a six-member
pyranose ring, named after the compound
pyran
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36. The furanose and pyranose forms of D-glucose
The furanose forms of D-glucose The pyranose forms of D-glucose
four carbons and 1 oxygen 6-membered ring with 5 carbons
and 1 oxygen
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37. glucopyranose
The ring structure representations of "Haworth
Projections“
The pyranose ring is formed by the reaction of the hydroxyl
group on carbon 5 (C-5) of a sugar with the aldehyde at carbon
1. This forms an intramolecular hemiacetal
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38. chair configuration of the glucopyranose ring
chair configurationThe α and β anomers of glucose chair form.
the position of the hydroxyl group (red or green) on the
anomeric carbon relative to the CH2OH group bound to carbon
5: they are either on the opposite sides (α), or the same side (β).
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39. mutarotation of glucose rings
Two ring forms of glucose differ in whether the hydroxyl group attached to
carbon number 1 is fixed below (alpha glucose ) or above (beta glucose )
A change in the specific optical rotation of light that takes place in the
solutions of freshly prepared sugars; Carbohydrates can change
spontaneously between the α and β configurations: a process known as
mutarotation.
α and β configurations Found in
equilibrium and spontaneously are
interconverted (mutarotation
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40. Pentose sugar
ribose
• Ribose is an organic compound with the
formula C5H10O5
• Ribose constitutes the backbone of RNA, a
biopolymer that is the basis of genetic
transcription
• Once phosphorylated, ribose can become a
subunit of ATP, NADH, important in
metabolism
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42. Deoxyribose
• deoxyribose, also called d-2-deoxyribose, five-
carbon sugar component of DNA
(deoxyribonucleic acid), where it alternates
with phosphate groups to form the
“backbone” of the DNA polymer and binds to
nitrogenous bases.
• The presence of deoxyribose instead of ribose
is one difference between DNA and RNA
(ribonucleic acid).
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43. Deoxyribose
replacement of the hydroyl group at the C2
position with hydrogen, leading to the net loss
of an oxygen deoxy.
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44. Disaccharides
• Disaccharides; contain two monosaccharides units
attached to one another through acetal bonds or as
known glycosidic bonds
• Covalent bonds between the anomeric hydroxyl of a
cyclic sugar and the hydroxyl of a second sugar (or
another alcohol containing compound) are termed
glycosidic bonds, and the resultant molecules are
glycosides.
• The linkage of two monosaccharides to form
disaccharides involves a glycosidic bond. Several
physiogically important disaccharides are sucrose,
lactose and maltose Dr. Siham Gritly 44
45. Glycosidic bond
• Glycosidic bond are formed between hydroxyl
group of one monosaccharide and hydroxyl
group of the next with the removal of water
• Glycosidic bonds involve the hydroxyl group
of the anomeric carbon (keto or aldehyde) of
one member of the pair of monosaccharide and
hydroxyl group on carbon 4 or 6 of the second
member
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46. • Glycosidic bond can be α or β
• Glycosidic bonds may be designated
• - α 1-4, β 1-4, α 1-6 and so on
• Important disaccharides are
• 1-maltose
• 2-lactose
• 3-sucrose
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47. Lactose. This disaccharide is comprise of a galactose linked to
glucose via a β-1-4 glycosidic bond. "Milk sugar" - it is the
principle carbohydrate of milk. Must be broken down into
galactose and glucose by the enzyme lactase.
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48. Sucrose. This disaccharide is glucose-α-1,2-fructose.
"Table sugar". No free anomeric carbon, therefore, not
a reducing sugar.
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49. Maltose. This disaccharide is glucose-α-1,4 glucose.
"Grain sugar". Formed from the partial hydrolysis of
starch. Has a free anomeric carbon and is therefore a
reducing sugar.
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50. Complex carbohydrates
• When polysaccharides are composed of a single
monosaccharide building block, they are termed
homopolysaccharides example starch and
glycogen.
• Polysaccharides composed of more than one type
of monosaccharide are termed
heteropolysaccharides, give sugar and
non-sugar like SO4 or NH4 gp e.g.
glycosaminoglycans ( found in connective tissue)
heparin present in mast cells as anticoagulant
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51. polysaccharides;
consist of many mono-saccharides. the main
monosaccharide found in polysaccharides is D-glucose.
Polysaccharides of nutritional important are
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52. Polysaccharides
Glycogen
1- Glycogen
• Made and found in human bodies
• Glycogen is the major form of stored carbohydrate
in animals. Stored in liver and muscle
• This vital molecule is a homopolymer of glucose in
α–(1,4) linkage
• Glycogen is a very compact structure that results
from the coiling of the polymer chains
• Not found in plants
• Saved for later use; the liver contain enzyme which
convert glycogen to glucose through the process
known as glycogenlysis.
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54. 2-Starch
is a storage polysaccharide composed of glucose
monomers
• Its structure is identical to glycogen,
Starch -- 2 forms:
• amylose: linear polymer of α(1-> 4) linked
glucose residues
• amylopectin: branched polymer of α(1-> 4)
linked glucose residues with α(1-> 6) linked
branches
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55. • starch; occur mainly in plant kingdom. Important
sources are cereals, millets, roots, tubers formed in
nature in large amounts.
• Starch hydrolyzed by amylase enzyme present in saliva
and in pancreatic juice to form maltose (disaccharide).
• during hydrolysis starch formed intermediate product
called dextrin. complete digestion of starch formed
glucose;
• starch--------dextrin----------maltose------------glucose
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58. • 3-Dietary fiber is a carbohydrates (or a
polysaccharide) that is incompletely absorbed in
humans and in some animals.
• *Dietary fiber consists mainly of cellulose, a
large carbohydrate polymer that is indigestible
because humans do not have the required
enzymes to digest it. There are two subcategories:
soluble and insoluble fiber. Whole grains, fruits
(especially plums, and figs) and vegetables are
good sources of dietary fiber.
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59. Cellulose
Cellulose in fibers is also a polymer of glucose
monomers ,but using beta rings (1-4 bond)
Dr. Siham Gritly 59
64. References
• Murry K. Robert, Granner K. daryl, Mayes A. peter, Rodwell W. Victor (1999). Harpers Biochemistry. Appleton and
Lange , twent fifth edition
• Campbell, Neil A.; Brad Williamson; Robin J. Heyden (2006). Biology: Exploring Life. Boston, Massachusetts:
Pearson Prentice Hall
• A. Burtis, Edward R. Ashwood, Norbert W. Tietz (2000), Tietz fundamentals of clinical chemistry
• Maton, Anthea; Jean Hopkins, Charles William McLaughlin, Susan Johnson, Maryanna Quon Warner, David
LaHart, Jill D. Wright (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall. pp.
52–59
• Maitland, Jr Jones (1998). Organic Chemistry. W W Norton & Co Inc (Np). p. 139. ISBN 0-393-97378-6.
• Nelson DL, Cox MM (2005). Lehninger's Principles of Biochemistry (4th ed.). New York, New York: W. H.
Freeman and Company.
• Matthews, C. E.; K. E. Van Holde; K. G. Ahern (1999) Biochemistry. 3rd edition. Benjamin Cummings.
• http://wiki.answers.com/Q/What_is_dehydration_synthesis#ixzz2BuiK645
Dr. Siham Gritly 64
65. • Sareen Gropper, Jack Smith and James Groff, Advanced Nutrition
and Human Metabolism, fifth ed. WADSWORTH
• Melvin H Williams 2010; Nutrition for Health, Fitness and Sport. 9th
ed, McGraw Hill
•
• Heymsfield, SB.; Baumgartner N.; Richard and Sheau-Fang P. 1999.
Modern Nutrition in Health and Disease; Shils E Maurice,
Olson A. James, Shike Moshe and Ross A. Catharine eds. 9th
edition
• Guyton, C. Arthur. 1985. Textbook of Medical Physiology. 6th
edition, W.B. Company
Dr. Siham Gritly 65
66. • Lehninger. Principles of bochemistry. by Nelson and Cox,
5th Edition; W.H. Freeman and Company
• Emsley, John (2011). Nature's Building Blocks: An A-Z
Guide to the Elements (New ed.). New York, NY: Oxford
University Press. ISBN 978-0-19-960563-7.
• Koppenol, W. H. (2002). "Naming of New Elements
(IUPAC Recommendations 2002)" (PDF). Pure and Applied
Chemistry 74 (5): 787–791. doi:10.1351/pac200274050787.
http://media.iupac.org/publications/pac/2002/pdf/7405x078
7.pdf.
Dr. Siham Gritly 66
