CARBOHYDRATECARBOHYDRATE

Prof. Dr. Drh. Maria Bintang, MS

PROGRAM KBKFK-UKI

REFERENCESREFERENCESLehninger. 2000. Principles of

biochemistry 3rd Ed.Michael W. King. 2006. Medical

Biochemistry. Murray R K, Granner D k, Mayers P a &

Rodwell V w. 2003. Harper’s Illustrated Biochemistry. 26th 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 FUNCTIONSSource 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

ALDOSES ALDOSES

KETOSESKETOSES

CARBOHYDRATE ACCORDING SIMPLE SUGAR UNITS

Carbohydrates

 Monosaccharides  Disaccharides  Polysaccharides Glucose  Maltose  Starch Galactose Lactose Glycogen Fructose Sucrose Cellulose

Ribose

Monosaccharides can be categorized Monosaccharides can be categorized according to their value of 'n,'according to their value of 'n,'

 n Category3 Triose4 Tetrose5 Pentose6 Hexose7 Heptose8 Octose

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 MonosaccharidesStructural 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

OligosaccharidesOligosaccharidesGlycosidic 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 (structura 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-Glucosealpha 1->4 links with extensive alpha1->6 branches

Cellulose D-Glucose beta 1->4 Chitin N-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

AmylopectinAmylopectinThe 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

LIPID LIPID

Prof. Dr. Drh. Maria Bintang, MS

PROGRAM KBKFK-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 class Potato tuber

Apple fruit

Soybean seed

Clover leaves Rye grass Spinach

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 LipidsThese 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  Structure Melt

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 UnsaturatedPalmitic Stearic Oleic Linoleic  Other

Animal OriginButter 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.

WAXESWax  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

• Lecithin contains the ammonium salt of choline joined to the phosphate by an ester linkage

CephalinsCephalinsPosphoglycerides 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

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