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CARBOHYDRATECARBOHYDRATE
Prof. Dr. Drh. Maria Bintang, MS
PROGRAM KBK
FK-UKI
Kepala Departemen Biokimia KedokteranFK-UKI
REFERENCESREFERENCES
Lehninger. 2008. Principles of biochemistry 5rd Ed.
Michael W. King. 2006. Medical Biochemistry.
Murray R K, Granner D k, Mayers P a & Rodwell V w. 2009. Harper’s Illustrated Biochemistry. 28th Ed.
Pratt,C.W.and Cornely K. 2004. Essential Biochemistry. Wiley International Edition.
Stryer, Lubert 1995. Biochemistry.4th Ed.
CARBOHYDRATE DEFINITION CARBOHYDRATE DEFINITION
Latin word " sacchararum" = sweet taste of sugars.
It means a "hydrate of carbon with formula of carbohydrate isCx(H2O)y (classic)
It is that the compounds are polyhydroxy aldehydes or ketones (modern)
Initially synthesized in plants by photosynthesis.
CARBOHYDRATE FUNCTIONSCARBOHYDRATE FUNCTIONS
Source energy : Glucose, fructose and starchStore energy : starch in plants or glycogen in
animals and humansProvide energy through metabolism pathways and
cyclesForm structural components in plant cells and tissues
: cellulosaCarrier genetic information : DNA, RNA
CARBOHYDRATE CLASSIFICATION CARBOHYDRATE CLASSIFICATION
• According to the number of individual simple sugar units : Mono, di and polysaccharides
• According to the functional groups : –Aldoses, contain the aldehyde group : glucose, galactose,
ribose.–Ketoses contain the ketone group : fructose–Reducing, sugars oxidized by Tollens' reagent (or Benedict's
or Fehling's reagents) : glucose, galactose, fructose, maltose, lactose–Non-reducing, sugars not oxidized by Tollens' or other
reagents : Sucrose and all polysaccharides
Monosaccharides can be categorized Monosaccharides can be categorized according to their value of 'n,'according to their value of 'n,'
n Category
3 Triose
4 Tetrose
5 Pentose
6 Hexose
7 Heptose
8 Octose
ALDOSES ALDOSES
KETOSESKETOSES
CARBOHYDRATE ACCORDING SIMPLE SUGAR UNITS
Carbohydrates
Monosaccharides Disaccharides Polysaccharides
Glucose Maltose Starch
Galactose Lactose Glycogen
Fructose Sucrose Cellulose
Ribose Cellobiose Hemicelluloce
Derivatives of MonosaccharidesDerivatives of Monosaccharides• Acids and Lactones : made by mild oxidation of an
aldose, (to form an aldonic acid)• Alditols : made by reducing the carbonyl group of a
sugar and resulting polyhydroxy compounds are called alditol (erythritol, D-mannitol, and D-glucitol/ sorbitol)
• Amino Sugars : made by replacing a hydroxyl of a sugar with an amine group (beta-D-glucosamine and beta-D-galactosamine)
• Glycosides formed by elimination of water between the anomeric hydroxyl of a cyclic monosaccharide and the hydroxyl group of another compound
Formed an aldonic acidFormed an aldonic acid
beta-D-glucosamine and beta-D-beta-D-glucosamine and beta-D-galactosaminegalactosamine
GlycosideGlycoside
Cyclic Forms of MonosaccharidesCyclic Forms of Monosaccharides
Structural form of many monosaccharides may be that of a cyclic hemiacetal.
Five and six-membered rings are favored over other ring sizes because of their low angle and eclipsing strain
Cyclic structures of this kind are termed
Furanose (five-membered) or pyranose (six-membered)
Haworth formulaHaworth formula
Pyranose forms of hexosesPyranose forms of hexoses
OligosaccharidesOligosaccharides
Glycosidic bonds between monosaccharides give rise to oligosaccharides and polysaccharides.
The simplest oligosaccharides, the disaccharides : sucrose, lactose,trehalose, maltose,gentiobiose, and cellobiose.
Oligosaccharides are also found as part of glycoprotein and play a role in cell recognition/identity
DisaccharidesDisaccharides
PolysaccharidesPolysaccharides
• Polysaccharides are polymers of monosaccharide units
• The monomeric units of a polysaccharide are usually all the same (homopolysaccharides), though there are exceptions (heteropolysaccharides).
• It differ in the composition of the monomeric unit, the linkages between them, and the ways in which branches from the chains occur
• Polysaccharides homopolysaccharides: – Glucose : glucans (structure in fungi, glucoses
joined by beta 1->3 or beta 1->6 bonds )– Mannose : mannans– Xylose : xylans ( polymers of D-xylopyranose)
• Polysaccharides heteropolymers : –Glucopyranose and mannopyranose joined by beta 1-
>4 linkages with beta 1->6 branches to other substituents. –The glucomannans and xylans are often grouped
together and called hemicellulose.
………….. Polysaccharides.. Polysaccharides
Polysaccharides Polysaccharides
Structures and Roles of some PolysaccharidesStructures and Roles of some Polysaccharides
Polysaccharide polymersPolysaccharide polymers
Polysaccharide Name
Monomeric Unit
Linkages
Glycogen D-Glucose
alpha 1->4 links with extensive alpha1->6 branches
Cellulose D-Glucose beta 1->4
ChitinN-Acetyl-D-glucosamine
beta 1->4
Amylopectin D-Glucosealpha 1->4 links with some alpha 1->6 branches
Amylose D-Glucose alpha 1->4
PolysaccharidesPolysaccharides
………….. Polysaccharides.. Polysaccharides
• Polysaccharides for energy storage in almost all higher organisms : Animals use glycogen, Plants use starch (amylose and amylopectin).
• Plants use different polysaccharides : cellulose for structural purposes in their cell walls.
• The exoskeleton of many arthropods and mollusks is composed of chitin, polysaccharide of N-acetyl-D-glucosamine
• The most important compounds in this class, cellulose, starch and glycogen are all polymers of glucose
Glycogen is a storage Carbohydrate found in animals
Starch is a storage Carbohydrate found in plants
Cellulose Plant is a structural
carbohydrate (woody material, cotton fibers)
It is rather insoluble and most animals cannot digest cellulose
All of these are polymers of glucose
Major carbohydrate reserve in plant tubers and seed endosperm where it is found as granules
Stored in chloroplastsof plantsThe largest source of starch is corn (maize),wheat,
potato, tapioca and riceConsists of two types of molecules:
amylose (normally 20-30%) amylopectin (normally 70-80%)
StarchStarch
…………. . StarchStarch
Starch stored in chloroplastsof plants
Amylopectin (without amylose) be isolated from 'waxy' maize starch and amylose (without amylopectin) isolated after specifically hydrolyzing the amylopectin with pullulanase
AmyloseAmyloseForms a colloidal dispersion in hot water
whereas amylopectin is completely insolubleLong polymer chains of glucose units connected
by an alpha acetal linkageAll of the monomer units are alpha -D-glucose,
and all the alpha acetal links connect C 1 of one glucose to C 4 of the next glucose
AmylopectinAmylopectin
The acetal linkages are alpha connecting C 1 of one glucose to C 4 of the next glucose
The branches are formed by linking C 1 to a C 6 through an acetal linkages.
Has 12-20 glucose units between the branches.
Natural starches are mixtures of amylose and amylopectin.
In glycogen, the branches occur at intervals of 8-10 glucose units, while in amylopectin the branches are separated by 10-12 glucose units.
CelluloseCellulosePolysaccharide polymer consisting linear with many
glucose monosaccharide units long polymer chains of glucose units connected by
a beta acetal linkage so it is makes it different from starchAll of the monomer units are beta-D-glucose, and all the
beta acetal links connect C 1 of one glucose to C 4 of the next glucose
Cellulose is a major component of the cell walls plants, and is difficult to digest by human because lacking enzymes to breakdown the beta acetal linkages
Compare Cellulose and Starch StructuresCompare Cellulose and Starch Structures
Cellulose: Beta glucose is the monomer unit in cellulose, as a result of the bond angles in the beta acetal linkage, cellulose is mostly a linear chain.
Starch: Alpha glucose is the monomer unit in starch, as a result of the bond angles in the alpha acetal linkage, starch-amylose actually forms a spiral much like a coiled spring.
Cellulose structureCellulose structure
GlycogenGlycogenPolymers consisting monosaccharide units (α-D-
glucose) connected by an alpha acetal linkageAll the alpha acetal links connect C 1 of one glucose
to C 4 of the next glucose and branches are formed by linking C 1 to a C 6 through an acetal linkages
The branches occur at intervals of 8-10 glucose units, while in amylopectin the branches are separated by 12-20 glucose units.
synthesized and stored mainly in the liver and the muscles
Structure of Glycogen
CARBOHYDRATE IMPORTANT REACTIONSCARBOHYDRATE IMPORTANT REACTIONS
1. Carbonyl group (alone)◦Oxidation to a carboxylic acid group◦Reduction to a hydroxyl group ◦Cyanohydrin reaction (and reaction with other nucleophiles)
2. Hydroxyl groups : • Ester formation – Oxidation to carbonyl◦Ether formation – Reduction to deoxy◦Cyclic acetal – Replacement with NH2, SH, or X
3. Both carbonyl and hydroxyl groups ◦Cyclic hemiacetals (pyranose/furanose)◦Formation of acetals (glycosides)◦Aldose/ketose isomerizations
DISEASES OF CARBOHYDRATE DISEASES OF CARBOHYDRATE METABOLISM DISODER METABOLISM DISODER
1. Diabetes mellitus2. Lactose intolerance3. Fructose intolerance4. Galactosemia5. Glycogen storage disease
BUKU ACUAN PRAKTIKUM BUKU ACUAN PRAKTIKUM BIOKIMIABIOKIMIA
LIPID LIPID
Prof. Dr. Drh. Maria Bintang, MS
PROGRAM KBK
FK-UKI
Definition of Lipid Definition of Lipid Lipids : hydrophobic or
amphipathic small molecules that may originate entirely or in part by carbanion-based condensations of thioesters (fatty acids, polyketides, etc.) and/or by carbocation-based condensations of isoprene units (prenols, sterols).
Lipids are biomolecules which are insoluble in water but soluble in organic solvents like ether and chloroform.
The functions of lipidsThe functions of lipidssource of energy for the body.parts of the membranes found within and between each cell
In the myelin sheath that coats and protects the nerves
Organ padding Body thermal insulation Hormone synthesis Fat soluble vitamin absorption
Classification of LipidsClassification of LipidsSimple Lipids :
◦Neutral fats (Triglycerides) - WaxesConjugated Lipids (polar lipids) :
◦Phospholipids - Cerebrosides - SulfolipidsDerived Lipids:
◦Fatty acids - Hydrocarbons◦Fatty alcohols - Vitamins A, D, E, K◦Fatty aldehydes
Miscellaneous: ◦Soaps - Oxidative polymers◦Coloring matters - Thermal polymers
Table The lipid class compositions (weight % of the total Table The lipid class compositions (weight % of the total lipids) of various plant tissueslipids) of various plant tissues
Lipid classPotato tuber
Apple fruit
Soybean seed
Clover leaves
Rye grassSpinach
cloroplasts
Monogalactosyldiacylglycerol 6 1 trace 46 39 36
Digalactosyldiacylglycerol 16 5 trace 28 29 20
Sulfoquinovosyldiacylglycerol 1 1 trace 4 4 5
Triacylglycerol 15 5 88
Phosphatidylcholine 26 23 4 7 10 7
Phosphatidylethanolamine 13 11 2 5 5 3
Phosphatidylinositol 6 6 2 1 2 2
Phosphatidylglycerol 1 1 trace 6 7 7
Others 15 42 5 3 4
Simple LipidsSimple Lipids
These are esters of fatty acids with various types of alcohol, distinguished into fats and oils
Fats are esters of fatty acids and glycerol.
A fatty acid is an organic acid with a hydrocarbon chain ending in a carboxyl (COOH) group
Fatty acidFatty acid• Fatty acids are merely carboxylic acids with long
hydrocarbon chains with length may vary from 10-30 carbons (most 12-18)
A fatty acid : Saturated and unsaturated• Saturated if there are no double bonds between carbons of
the molecular chainex : Palmitic acid (16 C) and stearic acid (18 C).
• Unsaturated if one (mono) or more (poly) double bonds occur between the carbon atoms of the chainex : oleic acid (18 C,1 double bond) , linoleic acid (18 C,2 double bond) and linolenic acid (18 C,3 double bond)
Saturated unsaturated
Acid Name
StructureMelt Point Symbol
SATURATED
Lauric CH3(CH2)10COOH +44 12:0
Palmitic CH3(CH2)14COOH +63 16:0
Stearic CH3(CH2)16COOH +70 18:0
UNSATURATED
Oleic CH3(CH2)7CH=CH(CH2)7COOH +16 18:1∆9
Linoleic CH3(CH2)4(CH=CHCH2)2(CH2)6COOH -5 18:2∆9,12
Linolenic CH3CH2(CH=CHCH2)3(CH2)6COOH -11 18:3∆9,12,15
Arachidonic CH3(CH2)4(CH=CHCH2)4(CH2)2COOH -50 20:4∆5,8,11,14
…………… …………… Fatty acidFatty acid
The unsaturated fatty acids have lower melting points than the saturated fatty acids.
The geometry of the double bond is almost always a cis configuration in natural fatty acids.
These molecules do not "stack" very well. The intermolecular interactions are much weaker than saturated molecules.
As a result, the melting points are much lower for unsaturated fatty acids.
Triglycerides / triacylglycerol Triglycerides / triacylglycerol (TAG)(TAG)
Main constituents of vegetable oils and animal fats
Have lower densities than water At normal room temperatures
may be solid ("fats" or "butters" ) or liquid (oils)
A chemical compound formed from one molecule of glycerol and three fatty acids
Biosyntesis triacylglycerol Biosyntesis triacylglycerol pathwaypathway
Percent Fatty Acid Present in Triglycerides
Fat or Oil Saturated Unsaturated
Palmitic Stearic Oleic Linoleic Other
Animal Origin
Butter 29 9 27 4 31
Lard 30 18 41 6 5
Beef 32 25 38 3 2
Vegetable Origin
Corn oil 10 4 34 48 4
Soybean 7 3 25 56 9
Peanut 7 5 60 21 7
Olive 6 4 83 7 -
WaxWaxA simple lipid which is an ester of a long-chain alcohol
and a fatty acidFound in nature as coatings on leaves and stems.Prevents the plant from losing excessive amounts of water.Example : Carnuba, Beeswax, SpermaceticMany of the waxes mentioned are used in ointments, hand
creams, and cosmetics. Paraffin wax, used in some candles, is not based upon the
ester functional group, but is a mixture of high molecular weight alkanes.
Ear wax is a mixture of phospholipids and esters of cholesterol.
WAXES
Wax Alcohol Fatty Acid Used
Carnauba CH3(CH2)28CH2-OH CH3(CH2)24COOHin floor,candies, polishes, varnishes, cosmetic products,
Beeswax CH3(CH2)28CH2-OH CH3(CH2)14COOH secreted by bees to make cells for honey and eggs
Spermacetic CH3(CH2)14CH2-OH CH3(CH2)14COOHfound in the head cavities and blubber of the sperm whale
Phosphoglycerides or PhospholipidsPhosphoglycerides or Phospholipids
Esters of only two fatty acids, phosphoric acid and a trifunctional alcohol - glycerol
Characterized : fatty acid chain and the phosphate/amino alcohol
The long hydrocarbon chains of the fatty acids are of course non-polar
Structure of a phospholipid, phosphatidate
………………………………Phosphoglycerides or PhospholipidsPhosphoglycerides or Phospholipids
The phosphate group has a negatively charged oxygen and a positively charged nitrogen to make this group ionic
There are other oxygen of the ester groups, which make on whole end of the molecule strongly ionic and polar
There are two common phospholipids:◦Lecithin contains the amino alcohol, choline.◦Cephalins contain the amino alcohols serine or
ethanolamine
LecithinLecithin
Found in egg yolks, wheat germ, and soybeans
Extracted from soy beans for use as an emulsifying agent in foods
• Major component in the lipid bilayers of cell membranes (cholesterol & phospholipid)
• Lecithin contains the ammonium salt of choline joined to the phosphate by an ester linkage
CephalinsCephalins
Posphoglycerides that contain ehtanolamine or the amino acid serine attached to the phosphate group through phosphate ester bonds
• Found in most cell membranes, particularly in brain tissues
• Important in the blood clotting process as they are found in blood platelets
SteroidsDerivatives of terpenes have
tetracyclic skeleton, consisting of three fused six-membered and one five-membered ring
are lipids with the principle function of signaling chemical biological activities.
Widely distributed in animalsInclude such well known
compounds as cholesterol, sex hormones, birth control pills, cortisone, and anabolic steroids
Steroid hormone
TerpenesTerpenesA majority of these compounds are found only in
plants, but some of the larger and more complex terpenes (squalene & lanosterol ) occur in animals
Considered to be made up of isoprene ( more accurately isopentane ) units, an empirical feature known as the isoprene rule
Classification Isoprene Units Carbon Atoms
monoterpenes 2 C10
sesquiterpenes 3 C15
diterpenes 4 C20
sesterterpenes 5 C25
triterpenes 6 C30
Lipid storage disorder Lipid storage disorder
The body's store of fat is constantly broken down and reassembled to balance the body's energy needs with the food available. Groups of specific enzymes help the body break down and process fats. Certain abnormalities in these enzymes can lead to the buildup of specific fatty substances that normally would have been broken down by the enzymes. Over time, accumulations of these substances can be harmful to many organs of the body. Disorders caused by the accumulation of lipids are called lipidosis. Other enzyme abnormalities result in the body being unable to properly convert fats into energy. These abnormalities are called fatty acid oxidation disorders
……………….. Lipid storage disorders.. Lipid storage disorders
Lipid storage disorders (or lipidoses) are a group of inherited metabolic disorders in which harmful amounts of lipids (fats) accumulate in some of the body’s cells and tissues. Types Lipid storage disorders
Niemann-Pick disease Fabry disease Farber’s disease Gangliosidoses = Tay-Sachs disease Krabbé disease Metachromatic leukodystrophy Wolman’s disease
THE ANDTHE AND
1. Carbonyl group 1. Carbonyl group
a. Oxidation to a carboxylic acid group Tollens test
Fehlings test
Glucose oxidase
b. Carbonyl group reductionb. Carbonyl group reduction
Glucose to glucitol (sorbitol)
c. Oxidation of non-anomeric hydroxyl c. Oxidation of non-anomeric hydroxyl groupsgroups
Periodate oxidation–can be used to quantitatively measure the
number of adjacent hydroxyls in a molecule.– It is used in the determination of polysaccharide
structure –The reaction is most rapid at pH 3-5
Hydrogen peroxide◦A non-specific oxidant◦Depolymerizes oligo- or polysaccharides
◦Involves a free radical mechanism
◦Employs an Fe+2 catalyst ◦Fe+2 + HO-OH ® Fe+3 + HO. + OH-
2. Hydroxyl groups 2. Hydroxyl groups
Esters◦Reaction of alcohol with acid anhydrideor acid chloride forms an ester
◦Usually done in the presence of a basesuch as triethylamine, pyridine, sodiumacetate, sodium hydroxide, (know as the Schotten-Bauman technique) and is done to shift the equilibrium toward the product ester
Use of acid anhydrides
EtherificationEtherification
Etherification of some polysaccharides–Modifies their properties–Makes them more useful
Examples (derivatives of cellulose)–Methyl (-CH3)–Carboxymethyl (-CH2COO-Na+)–Hydroxypropyl (-CH2CH(OH)CH3)
Cyclic acetalsCyclic acetalsThe hydroxyl groups on carbohydrates react
with aldehydes or ketones to form cyclic acetals
Common carbonyl compounds include acetone and benzaldehyde
Sometimes such acetals occur naturally, as in xanthan gum
http://www.cfs.purdue.edu/class/f&n630/Virt_Class_2/CHOreactions.htmhttp://www.elmhurst.edu/~chm/vchembook/550lipids.htmlhttp://www.nicerweb.com/bio1151b/Locked/media/ch05/polysaccharides.html