Carbohydrates & Related Compounds

Carbohydrates

• Most abundant group of organic molecules in nature

• First product of biological process that converts electromagnetic energy into chemical energy

• Monosaccharides

• Disaccharides

• Polysaccharides

Classification of Carbohydrates

Monosaccharides

Simplest CHO units

• Bioses

• Trioses

• Tetroses

• Pentoses

• Hexoses

• Heptoses

Sugars can be:

• Ribose

• Xylose

Examples of aldose

• Ribulose

• Xylulose

examples of ketoses

Disaccharides

Upon hydrolysis yields two molecules of monosaccharides

Sucrose aka Table sugar

Glucose + Fructose =

Maltose aka Malt sugar or Maltobios

Glucose + Glucose =

Lactose or Milk sugar

Glucose + Galactose =

Trisaccharides

Liberate 3 molecules of monosaccharides on hydrolysis

Raffinose

Fructose + Galactose + Glucose =

Gentianose

Fructose + glucose + glucose =

Polysaccharides

On hydrolysis they give an indefinite number monosaccharides

Reduction of Fehling’s Solution

Fehling’s A and B + Solution of CHO = (+) Brick red ppt

Molisch test

Alpha-naphthol + conc H2SO4 + CHO = (+) Purple ring

Osazone formation

Phenylhydrazine HCL + Na acetate + acetic acid + CHO = (+) yellow crystals

Copper (II) sulfate

Fehling A is

KNa tartrate or Rochelle’s Salt

Fehling B:

Molisch test

General test for CHO

Kowarsky tests

Modification of osazone, what test?

Resorcinol Test for ketones (Selivanoff’s test)

Crystal of resorcinol + CHO + HCL = (+) rose color

Test for pentoses (Bial’s Test)

HCL + Phloroglucinol = (+) blue green

Test for deoxy sugar (Keller-kiliani test)

Deoxysugar + acetic acid + FeCl3 = (+) Reddish brown

Furfural test

CHO + Phosphoric acid = (+) pink or red stain in the reagent

Flower-like crystals

Sucrose/maltose shape

Fluffy crystals

Lactose shape

Broom-like crystals

Monosaccharides shape

6 CO2 + 12 H20 + (energy) → C6H12O6 + 6 O2 + 6 H20

Production of monosaccharide by photosynthesis

Xylose

Pentose obtained by boiling corn cobs, straw or similar materials with dilute acids to hydrolyze the xylan polymer.

Xylose

Normally absorbed from small intestine but is not metabolized to significant extent by mammalian enzymes.

Xylose

Use: Diagnostic aid for intestinal malabsorption

• D-xylose

• Wood sugar

Xylose is also known as

Glucose

• Sugars that occur naturally in grapes and other fruits

• Production: Controlled enzymatic hydrolysis of starch

• Uses: Nutrient and Pharmaceutical necessities

• Dextrose

• Blood sugar

• Physiologic sugar

Other name for Glucose

Dextrose excipient

Glucose preparation: crystalline dextrose monohydrate; undergone less rigorous purification

Liquid glucose

Glucose preparation: product of incomplete hydrolysis of starch

Dextrates

Glucose preparation: mixture of saccharides

Calcium Gluconate

• Calcium salt of gluconic acid

• Electrolyte replenisher

• Less irritating for parenteral use than CaCl2

• Used to obtain therapeutic effects of calcium

• Calcium gluceptate

• Calcium levulinate

Calcemic compounds

Ferrous gluconate

• Ferrous salt of gluconic acid

• Hematinic: Iron deficiency anemia

• Less gastric distress than inorganic ferrous salts

Fructose

A ketone sugar that occurs naturally in most sweet fruits and in honeys

D-fructose, levulose, fruit sugar

Fructose aka?

• Inversion of aqueous solutions of sucrose and subsequent separation of fructose from glucose

• Hydrolysis of inulin

Sources of fructose?

Galactose

• Brain sugar

• Most rapidly absorbed from the small intestines

• C4 epimers with glucose

• Nerve fibers are composed of these

Aldohexose

Galactose aka?

Sucrose

Obtained from following plants:

• Sugar cane (Saccharum officinarum),

• Sugar beet (Beta vulgaris

• Sugar maple (Acer saccharum)

• Saccharum

• Sugar

• Table sugar

• Invert sugar

Sucrose is aka?

• Juice is extracted through crushing the stem between iron rollers

• Juice is boiled with lime to neutralize and coagulate the albumin

• Filtered and decolorized with sulfur dioxide concentrated and crystallized

Production of sucrose through sugar cane steps:

Molasses

By product from Sugar cane production

Molasses

Residual, dark-colored syrup of when crystals of sugar no longer obtainable

Sucrose

• Pharmaceutic necessity for syrups

• Demulcent - Nutrient

• In sufficient conc in aq solutions: bacteriostatic and preservative

• Masks disagreeable taste

Maltose

Consists of two molecules of glucose that are linked by an α-(1,4') glycosidic bond.

Barley (Hordeum vulgare)

Maltose is produced during the germination of _______

Maltose

Major degradation product of starch

Malt sugar, Maltobiose

Maltose is aka

Lactose (Milk sugar)

• Obtained from cow’s milk (Bos taurus) (Bovidae). Specifically crystallized from the whey during the production of cheese

• Tablet diluent

• Instant feeding

Cow’s milk (Bos taurus)

Lactose is obtained from ______

Whole milk > Butter milk > Skimmed milk > Coagulate milk > Cheese

Preparation of Milks

Condensed milk

Prepared by partial evaporation of milk in a vacuum and consequently sterilized in hermetically container by autoclaving

Malted milk

Prepared by evaporating milk with an extract of malt

Kumyss

Fermented milk

Lactulose

• Semisynthetic sugar prepared by alkaline rearrangement of lactose.

• Which on hydrolysis will yield fructose and galactoe

Laxative

Lactulose can be used as

• Ducitol/galactitol

• Plant acids

  • Tartaric acid

  • citric acid

  • lactic acid

• Alcohol

• Mannitol (D-Mannitol)

Drugs containing compounds metabolically related to sugars cherry juice (Succus cerasi)

Dulcitol/Galactitol

• Derived from galactose

• Liquid expressed from fresh, ripe fruit of Prunus Cerasus (Rosaceae)

Prunus cerasus (Rosaceae)

Dulcitol/Galactitol is a liquid expressed from fresh, ripe fruit of ________

1% malic acid

dulcitol/galactitol Constituent: Contains not less than

• Benzoic acid

• Clear solution

dulcitol/galactitol Mixture is preserved with _______ & allowed to stand until juice produces________that does not cloudy within 30 minutes.

Flavored vehicle for Cherry syrup

Uses of dulcitol/galactitol

Tartaric acid

• Obtained as by-product of the wine-industries

• Used as a substitute for citric acid in buffering system and ingredient in effervescent formulation

Carl Wilhelm Scheele 1784

Citric acid was first isolated by?

Citric Acid

• Obtained from lemons, lime and pineapples but mostly in fermentation of sucrose

• Useful in buffering system, acidulant in effervescent formulation

Citric acid

• Ingredient in K citrate, citric acid solution, Na citrate, systematic alkalinizers

• Anticoagulants

• Citrate dextrose solution

• Citrate phosphate dextrose solution

Anticoagulants:

Lactic acid

Obtained by the lactic fermentation of sugars or is prepared synthetically

85%

Lactic acid and lactic acid lactate: NLT %?

90%

Lactic acid and Lactic acid lactate: NMT %?

Lactic acid

Used as an acidulant in infant formulas and is used feminine wash

Lactic acid

Na electrolyte replenisher: metabolic acidosis

Calcium lactate replenisher

Ca replenisher derived from lactic acid

Alcohol

• Liquid containing not less than 92.3% by weight corresponding to 94.9% by volume of ethanol at 15.56°C

• Product of fermentation & distillation

• 92.3%

• 94.9%

• 15.56 C

Alcohol liquid contains not less than ____ by weight corresponding to ____ by volume of ethanol at _______

wine

Yeast

Distilled wine

Brandy

Malted grain

Whisky

Molasses

Rum

Diluted alcohol

Mixture of alcohol and water in which the percentage of ehtanol by volume at 15.56 C is 48.4 - 49.5 %

• 15.56 C

• 48.4-49.5%

Diluted Alcohol is a mixture of alcohol and water in which the percentage of ehtanol by volume at _____ is ______

Mannitol (D-Mannitol

Hexahydric alcohol obtained by the reduction of mannose or isolation from manna.

Manna

Is a saccharide exudate obtained from the stem of Fraxinus ornus (Oleaceae)

• Laxative

• Diagnostic aid

• Diuretic (50-100g daily)

Uses of Mannitol