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.
Dr. Siham Gritly 3
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
Dr. Siham Gritly 4
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
Dr. Siham Gritly 5
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.
Dr. Siham Gritly 6
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
Dr. Siham Gritly 8
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
Dr. Siham Gritly 9
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.
Dr. Siham Gritly 10
11. Aldotriose and ketotriose
glyceraldehyde is especially
important because the more complex monosaccharides may
be considered to be derived from them
Dr. Siham Gritly 11
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
Dr. Siham Gritly 13
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
•
Dr. Siham Gritly 14
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
Dr. Siham Gritly 15
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
Dr. Siham Gritly 16
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
Dr. Siham Gritly 18
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)
Dr. Siham Gritly 19
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
Dr. Siham Gritly 20
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
Dr. Siham Gritly 21
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.
Dr. Siham Gritly 22
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
Dr. Siham Gritly 23
24. Ring and chair configuration of glucose
Dr. Siham Gritly 24
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.
Dr. Siham Gritly 25
26. Fischer projection of glyceraldehyde Aldotriose
D,L designation refers to the configuration the
highest-numbered asymmetric center
Dr. Siham Gritly 26
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
Dr. Siham Gritly 28
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.
Dr. Siham Gritly 30
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
Dr. Siham Gritly 31
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.
Dr. Siham Gritly 32
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
Dr. Siham Gritly 33
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,
Dr. Siham Gritly 34
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
Dr. Siham Gritly 35
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
Dr. Siham Gritly 36
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
Dr. Siham Gritly 37
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).
Dr. Siham Gritly 38
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
Dr. Siham Gritly 39
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
Dr. Siham Gritly 40
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).
Dr. Siham Gritly 42
43. Deoxyribose
replacement of the hydroyl group at the C2
position with hydrogen, leading to the net loss
of an oxygen deoxy.
Dr. Siham Gritly 43
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
Dr. Siham Gritly 45
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
Dr. Siham Gritly 46
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.
Dr. Siham Gritly 47
48. Sucrose. This disaccharide is glucose-α-1,2-fructose.
"Table sugar". No free anomeric carbon, therefore, not
a reducing sugar.
Dr. Siham Gritly 48
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.
Dr. Siham Gritly 49
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
Dr. Siham Gritly 50
51. polysaccharides;
consist of many mono-saccharides. the main
monosaccharide found in polysaccharides is D-glucose.
Polysaccharides of nutritional important are
Dr. Siham Gritly 51
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.
Dr. Siham Gritly 52
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
Dr. Siham Gritly 54
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
Dr. Siham Gritly 55
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.
Dr. Siham Gritly 58
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