CARBOHYDRATES (MIDTERM)

Carbohydrates

Carbohydrates

Major source of energy from our diet, composed of C H O

Saccharides

These are also known as “sugars”

Sweetening agent

This is another usage of carbohydrates

Vegetables, Fruits, Starches, Meat, Egg

This is where carbohydrates are commonly found

Chlorophyll

It captures light during photosynthesis in plants

Light

Is an agent or catalyst that makes the reaction of glucose and plants possible

Respiration

Carbs are oxidized in living cells

Polyhydroxyaldehyde/polyhydroxyketone

A substance that carbohydrates give on hydrolysis

Monosaccharide

It is the simplest among saccharides that cannot be hydrolyzed to a simpler formula. Cyclic, closed string.

Aldose and ketose

Two types of monosaccharides

Aldose

A monosaccharide that contains an aldehyde group

Ketose

A monosaccharide that contains a ketone group

Oligosaccharide

A biological intermediate, 3-10 sugars

Polysaccharide

More than 10 saccharides that can still break down and produce monosaccharide

Aldo

Carbonyl carbon at the terminal carbon

Keto

Carbonyl carbon in between two carbons

Glyceraldehyde and Dihyroxyacetone

Two trioses in monosaccharides

Glyceraldehyde

Triose for aldose, it contains a stereocenter

Dihyroxyacetone

Triose for ketose

Fischer projection

Emil fischer proposed that it has tetrahedral stereocenters.

Horizontal Lines

It is an indication where bonds project forward

Vertical Lines

It is an indication that bonds are projecting to the rear

Penultimate carbon

Second to the last carbon

Enantiomers

Stereoisomers that are mirror images but doesn’t have the same confirmation

Diastereoisomers

It does not mirror image

Epimers

It differs in one chiral carbon only

D-erythrose, D-threose

Most common two D-aldotetroses

D-ribose, 2-Deoxy-D-ribose

Most common two D-alpentoses

D-sugars

Natural sugars

L-sugars

Synthetic sugars, these are manufacturized and are sweetening agents

D-galactose

These are present in milk and is a fruit sugar too

D-fructose

The sweetest of all monosaccharides that gives the sweet taste of most sugars

1

In numbering carbons, you start at the carbonyl carbon

Anomeric carbon

The result of cyclic hemiacetal formation

Anomers

Carborhydrates that differ in configuration only at their anomeric carbon

Haworth Projections

These are cyclic monosaccharides that has 5 and 6 membered hemiacetals that is represented as planar pentagons or hexagons. Commonly writteh with anomeric carbon on the right and hemiacetal oxygen to the back right.

Beta

-OH on the carbon is cis to the terminal -CH2OH, projects upward

Alpha

It is trans, projects downward

Furanose

5 membered ring (pentagon)

Pyranose

6 membered ring (hexagon)

Ascorbic Acid (Vitamin C)

This is used to create and make collagen, it is physiologically active and boosts our immune system

Biochemically and Industrially

Ascorbic acid canbe synthesized both

L-dehydroascorbic

Easily oxidized by ascorbic acid

Reducing sugar

It reduces an oxidizing agent

Aldehyde groups

It can be reduced to alcohol group (by hydrogen)

Carboxylic acid

The result of the oxdized aldehyde groups

Alditol

Reduction of the c=o group of a monosaccharide gives this polyhydroxyl compound

D-Glucitol/D-Sorbitol

Sugar alcohols that are found in many candies (alditol)

Reduction of monosaccharides

Involves a carbonyl group and sugar alcohols

Phospheric Esters

Particularly important in metabolism of sugars (enzyme phophorylase glucose)

Glycosides

OH of the anomeric is replaced by OR

Furanosides

Glycosides in furanoses

Pyranosides

Glycosides in pyranoses

Glycosidic bond

Anomeric carbon to the -OR group

Amino sugars

Carbs + amino, compound sugars

Disaccharides

It is combined together by glycosidic bonds

Sucrose

One unit of D-glucose and one unit of D-frutose joined by an a-1, b-2-glycosidic (sugar cane, sugar beet)

Anomeric Carbon

You need this to become a reducing sugar

Lactose

b-1, b-4 glycosidic bonds, carbons used in bonding is carbon no, 1 and no. 4 (milk in humans and cows)

Maltose

(beers, ferment) a-1, a-4 glycosidic bond

Polysaccharide

b-1,4-glycosidic bonds

Cellulose

A major structural component of plants esp wood and plant fibers, cannot be digested by humans (b-1,4)

Alpha Enzymes

Human only has this type of enzymes (only starches)

Cellobiose

Two unit of glucose of cellulose

Starch

Energy storage in plants and is present staple foods (polymer of a-D-Glucose units)

Amylose and amylopectin

2 Types of starch

Amylose

A type of starch that is continous and has unbranched chains, straight chain

Amylopectin

A type of starch that is highly branched polymer

Glycogen

Animal starch that is found mostly on muscles and liver

Chitin

A major structural component of the exoskeletons of invertebraes, insects, and crustaceans

Bacterial cell wall

Biological materials and is composed of polysaccharides

NAM-NAG

These are what prokaryotic cell walls are constructed, cross-linked by small peptides

D-Ala, D-Gin

Two amino acids of the D-series of a tetrapeptide

Gram-negative

It is harder to penetrate compared to Gram-positive (cytoplasmic membranes)

Plant Cell Walls

It consists of a large cellulose and pectin that functions as an intercellular cementing material

Pectin

A polymer of D-galacturonic acid, a-1,4 glycosidic bonds

Glycosaminoglycans

A repeating dissacharide where one of the monomers is an amino sugar

Heparin

Natural coagulant of blood

Hyaluronic Acid

Vitreous humor of the eye and lubricationg the joints

Chondroitin sulfate and keratin sulfate

A component of connective tissue

Glycoproteins

A sugar with proteins

Antigenic determinants

Carbs also play this role where antibodies recognize and to which they bond

A

Blood type that has NAGal

B

Blood type that has Gal

AB

Blood type that has NAGal and Gal

O

Blood type that niether has NAGal

L-fucose

Synthesized biochemically from D-mannose

NAGal

N-acetyl-D-galactosamine

Gal

D-Galactose

NAGlu

N-acetyl-D-glucosamine

Fuc

L-fructose

Triose

C3H6O3

Tetroise

C4H804

Pentose

C5H10O5

Hexose

C6H12O6

Heptose

C7H14O7

Octose

C8H16O8

Top

Where is the most oxidized group written

D-monosaccharide

-OH is on the penultimate carbon on the right

L-monosaccharide

-OH is on the penultimate carbon on the left