Introduction and defination Classification Reducing sugars Non-reducing sugars General properties Common disaccharides 1) sucrose Origin Structure Properties Function

1. disaccharides
By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. synopsis
 Introduction and defination
 Classification
 Reducing sugars
 Non-reducing sugars
 General properties
 Common disaccharides
 1) sucrose
 Origin
 Structure
 Properties
 Function

3.  2) lactose
 Origin
 Structure
 Properties
 Function
 3)maltose
 Origin
 Structure
 Properties
 function

4.  Advantages
 Disadvantages
 Conclusion
 References
 Thank you

5.  A DISACCHARIDE OR BIOSE IS THE
CARBOHYDRATE FORMED WHEN
TWO MONOSACCHARIDES UNDERGO A
CONDENSATION REACTION INVOLVING
THE ELIMINATION OF A SMALL
MOLECULE, SUCH AS WATER FROM
THE FUNCTIONAL GROUPS ONLY .
 WORD SACCHARIDE COMES FROM THE
GREEK WORD σάκχαρον (sákkharon),
MEANING "SUGAR".

6.  REDUCING DISACCHARIDES- HAS A
FREE ALDEHYDE OR KETO GROUP (
HEMIACETAL UNIT) EXAMPLE-
CELLOBIOSE, MALTOSE AND LACTOSE
 NON-REDUCING DISACCHARIDES –
ACETAL LINKAGE BETWEEN THEIR
ANOMERIC CENTERS AND NEITHER
MONOSACCHARIDE HAS A FREE
ALDEHYDE OR KETO GROUP.
EXAMPLE -SUCROSE AND TREHALOSE.

7.  OLIGOSACCHARIDES (GK.OLIGO=FEW) CONTAIN TWO
TO TEN MONOSACCHARIDES UNITS JOINED BY
GLYCOSIDIC LINKAGES.
 DISACCHARIDES FORM AN AQUEOUS SOLUTION WHEN
DISSOLVED IN WATER.
 THEY ARE CRYSTALLINE , WATER-SOLUBLE , SWEET TO
TASTE , STICKY-FEELING.
 MONOSACCHARIDES WHICH CONTAIN AN ALDEHYDE
GROUP ARE KNOWN AS ALDOSES, AND THOSE WITH
A KETONE GROUP ARE KNOWN AS KETOSES
 THE PHYSICAL AND CHEMICAL PROPERTIES OF
DISACCHARIDES ARE VARIABLE BECAUSE OF GLYCOSIDIC
BOND. THE CONSTITUENT OF MONOSACCHARIDES
DECIDES THE PROPERTIES AND NATURE OF
DISACCHARIDES

8. Disaccharide Unit 1 Unit 2 Bond
SUCROSE (TABLE
SUGAR, CANE
SUGAR, BEET
SUGAR, OR
SACCHAROSE)
GLUCOSE FRUCTOSE α(1→2)β
LACTULOSE GALACTOSE FRUCTOSE β(1→4)
LACTOSE (MILK
SUGAR)
GALACTOSE GLUCOSE β(1→4)
MALTOSE GLUCOSE GLUCOSE α(1→4)
TREHALOSE GLUCOSE GLUCOSE α(1→1)α
CELLOBIOSE GLUCOSE GLUCOSE β(1→4)
COMMON DISACCHARIDES

9. CELLOBIOSE ((4-O-β-D-glucopyranosyl-D-
glucose))
RESULTS FROM THE HYDROLYSIS
OF CELLULOSE BY BACTERIA.
MAMMALS LACK THE NECESSARY
ENZYMES—
CELLOBIOHYDROLASES AND ENDO-
CELLULASES—TO HYDROLYZE
CELLULOSE.
CELLOBIOSE CONSTITUTES
MATERIALS SUCH AS COTTON AND
PAPER. MALTOSE IS A HOMOPOLMYER
OF CELLOBIOSE.

10. GENTIOBIOSE (6-O-β-D-
glucopyranosyl-D-glucose) IS
FOUND IN MANYGLYCOSIDES
SUCH AS AMYGDALIN
LACTOSE (4-O-β-D-galactopyranosyl-D-
glucose) IS THE PREDOMINANT
DISACCHARIDE FOUND IN MILK. LACTOSE
INTOLERANCE IS A CONDITION IN WHICH
THERE IS A LACK OF THE ENZYME
LACTASE.
GALACTOSAEMIA IS A CONDITION THAT
RESULTS FROM AN INABILITY TO PROCESS
THE D-GALACTOSE AFTER HYDROLYSIS.

11. LAMINARIBIOSE IS A
POLYSACCHARIDE BUILDING UNIT
FOR LAMINARIN (BROWN ALGAE),
PACHYMAN (FUNGI), PARAMYLON
(UNICELLULAR ALGAE), AND CALLOSE
MALTOSE (4-O-α-D-glucopyranosyl-
D-glucose) RESULTS FROM
HYDROLYSIS OF STARCH BY
ENZYMES (AMYLASES) I N THE
MAMMALIAN DIGESTIVE TRACT.
THE GLYCOSIDIC LINKAGE IS Α
AND THAT OF THE
HOMOPOLYMER CELLOBIOSE IS
AB LINKAGE. MALTOSE IS USED
AS A SWEETNER AND AS A
SUBSTRATE FOR FERMENTATION.
ALSO THE CONSTITUENT OF THE
POLYMER AMYLOSE.

12. MANNOBIOSE IS THE UNIT
FOR THE PLANT
POLYSACCHARIDE
MANNAN.
XYLOBIOSE IS THE
UNIT FOUND IN
MANY
POLYSACCHARIDES
SUCH AS THE
XYLANS THAT
CONSTITUTE PLANT
CELL WALLS

13. Non-reducing disaccharides
SUCROSE (β-D-fructofuranosyl α-D-
glucopyranoside) IS THE PREDOMINANT
DISACCHARIDE FOUND IN SUGAR CANE AND
SUGAR BEET. IT IS A WELL KNOWN
SWEETNER AND HAS A FIVE-MEMBERED
FURANOSY L UNIT.
TREHALOSE IS FOUND IN MICROBES,
FUNGI, AND CERTAIN INSECTS. ONE
ISOMER IS NEOTREHALOSE WITH AN
α,β LINK. ANOTHER ISOMER IS
ISOTREHALOSE WHICH HAS β,β LINK.

14. ORIGIN AND COMPOSITION –
IT IS COMPOSED OF ONE D-GLUCOSE
MOLECULE AND ONE D-FRUCTOSE
MOLECULE.
THE SYSTEMATIC NAME FOR SUCROSE, O-
α-D-GLUCOPYRANOSYL-(1→2)-D-
FRUCTOFURANOSIDE.
OBTAINED FROM SUGAR CANE AND
SUGAR BEET

15. properties
 CALLED AS SUGAR-CANE , SUGAR OF COMMERCE
PRODUCED BY SUGAR BEETS,SWEET IN TASTE.
 MADE FROM GLUCOSE AND FRUCTOSE.
 NON-REDUCING SUGAR , CANNOT FORM OSAZONES.
 MAJOR CARBOHYDRATE PRODUCED IN
PHOTOSYNTHESIS.
 MOST ABUNDANT AMONG NATURALLY OCCURING
SUGARS.
 ITS BOTH FUNCTIONAL GROUPS ARE HELD
TOGETHER AND PROTECTED FROM OXIDATIVE
ATTACKS.

16.  WHITE CRYSTALLINE SOLID, SOLUBLE IN
WATER MELTING POINT 180° C.
 WHEN HEATED ABOVE ITS MELTING POINT ,
IT FORMS A BROWN SUBSTANCE KNOWN AS
CARAMEL.
 DEXTROROTATORY.
 ON HYDROLYSIS WITH DILUTE ACIDS
SUCROSE YIELD AN EQUIMOLECULAR
MIXTURE OF D(+)GLUCOSE AND D(-
)FRUCTOSE.
 C12H22O11 + H2O ------------------> C6H12O6 + C6H12O6
 SUCROSE GLUCOSE FRUCTOSE

17. SERVING AS STORED FOOD.
AS SWEETENING AGENT IN FOOD
INDUSTRY.
MAJOR ELEMENT IN CONFECTIONERY
AND DESSERTS.
FOOD PRESERVATIVE IN SUFFICIENT
CONCENTRATIONS.

18. ORIGIN AND COMPOSITION
— THE NAME COMES FROM LAC
OR LACTIS, THE LATIN WORD FOR
MILK, PLUS THE -OSE ENDING
USED TO NAME SUGARS.
IT HAS A FORMULA OF C12H22O11.
COMPOSED OF ONE D- GALACTOSE
MOLECULE AND ONE D-GLUCOSE
MOLECULE THE SYSTEMIC NAME
FOR LACTOSE IS O-β-D-
GALACTOPYRANOSYL-(1→4)-D-
GLUCOPYRANOSE

19. PROPERTIES
 OCCURS NATURALLY IN MAMMALIAN MILK.
 WHITE CRYSTALLINE SOLID, SOLUBLE IN WATER
MELTING POINT 203° C
 DEXTROROTATORY.
 WHEN IT IS HYDROLYSED WITH DILUTE ACID IT YIELDS
MOLECULES OF GLUCOSE AND GALACTOSE.
 C12H22O11 + H2O---------------------> C6H12O6 + C6H12O6
 LACTOSE GLUCOSE GALACTOSE
 REDUCING SUGAR AND FORMS OSAZONE

20. FUNCTION
 WHEY IS MADE OF UP 6.5% SOLIDS OF WHICH 4.8% IS
LACTOSE
 BLAND FLAVOUR LENTTO USES AS A CARRIER AND
STABILISER OF AROMAS AND PHARMACEUTICAL PRODUCTS
 PURIFIED LACTOSE - HIGH CALORIE DIET ADDITIVE.
 TO SWEETEN STOUT BEER AS IT IS NON-FERMENTABLE IN
BEER;
(MILK STOUT OR A CREAM STOUT)
 ADDED TO PILLSAS A FILLER BECAUSE OF ITS PHYSICAL
PROPERTIES (I.E., COMPRESSIBILITY)AND LOW PRICE.

21. MALTOSE(BEER-SUGAR)
 -- MALTOSEOR MALT SUGAR, IS FORMED FROMTWO
UNITS OF GLUCOSE JOINEDWITH AN Α(1→4)BOND ,
FORMED FROM A CONDENSATION REACTION.
 THE ISOMER " ISOMALTOSE “HASTWO GLUCOSE
MOLECULES LINKEDTHROUGHAN α(1→6) BOND.
 IT IS FOUND IN GERMINATING SEEDS SUCH AS BARLEY
MALTOSE ISTHE SECOND MEMBEROF AN IMPORTANT
BIOCHEMICAL SERIES OF GLUCOSE CHAINS.
 MALTOSE ISTHE DISACCHARIDE PRODUCEDWHEN
AMYLASE BREAKS DOWN STARCH .

23. PROPERTIES
 WHITE CRYSTALLINE SOLID, SOLUBLE INWATER
MELTING POINT 160°-165°C
 IT IS DEXTROROTATORY.
 WHEN IT IS HYDROLYSEDWITH DILUTE ACID ITYIELDS
TWO MOLECULESOF D(+) GLUCOSE .
 IT IS A REDUCING SUGAR.
 C12H22O11 + H2O--------------------->C6H12O6 + C6H12O6
 Maltose Glucose Glucose

24. MALTOSE IS A IMPORTANT
COMPONENT IN THE PROCESS OF
CREATING FERMENTED BARLEY
WHICH CAN BE USED TO BREW
BEER.
COMMONLY USED IN
CONFECTIONARIES.

25. ADVANTAGES
 DISACCHARIDES ARE A MAJOR COMPONENT OF
CARBOHYDRATES,( MOST ABUNDANTLY FOUND BIOMOLECULES )
 LACTOSE ( MAJOR COMPONENT OF MILK),FEED BY INFANTS AND
IT ACTS AS A COMPLETE SOURCE OF ESSENTIAL NUTRIENTS
FOR THE INDIVIDUAL.
 MALTOSE OR MALT SUGAR ( MAJOR COSTITUENT IN BEER).
 SUCROSE IS THE MOST SWEETEST SUGAR MAJORLY USED AS
SWEETENING AGENT IN FOOD INDUSTRY.
 PRESENT IN THE FORM OF STORED FOOD BOTH IN ANIMALS
AND PLANTS.

26. DISADVANTAGES
 TOOTH DECAY ORAL BACTERIA SUCH
AS STREPTOCOCCUS MUTANS LIVE IN
DENTAL PLAQUE AND METABOLIZE ANY
SUGARS INTO LACTICACID. HIGH
CONCENTRATIONS OF ACID MAY
RESULT ON THE SURFACEOF A TOOTH,
LEADING TO TOOTH
DEMINERALIZATION.
 MUSCULAR DEGENERATION
 CARDIOVASCULAR PROBLEMS

27. DISACCHARIDES ARE A N
IMPORTANT COSTITUENT OF
CARBOHYDRATES SERVING AS A
STORED FOOD RESERVE IN PLANTS
AS WELL AS IN ANIMALS,PROVIDING
THE IMMEDIATE SOURCE OF
ENERGY.
 IN ADDITION TO THIS, THEIR
SEVERAL FORMS ARE COMMERCELY
USED,AS FOR THE PRODUCTION OF
BEER AND IN FOOD INDUSTRY.

28. Nelson and cox – principles of
biochemistry
HARPER ILLUSTRATED
BIOCHEMISTRY BY MURRAY
INTERNET SOURCE – WIKIPEDIA.COM