1 / 81

CARBOHYDRATES

CARBOHYDRATES. INTRODUCTION . CARBOHYDRATES –MOST IMPORTANT ORGANIC COMPOUNDS IN THE NATURE CHIEF SOURCE OF ENERGY MADE UP OF CARBON,HYDROGEN AND OXYGEN (1:2:1) BUILDING BLOCKS OF A MOLECULE IMPORTANT SOURCE OF ENERGY REQUIRED FOR METABOLIC ACTIVITIES

phoebe
Télécharger la présentation

CARBOHYDRATES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CARBOHYDRATES

  2. INTRODUCTION • CARBOHYDRATES –MOST IMPORTANT ORGANIC COMPOUNDS IN THE NATURE • CHIEF SOURCE OF ENERGY • MADE UP OF CARBON,HYDROGEN AND OXYGEN(1:2:1) • BUILDING BLOCKS OF A MOLECULE • IMPORTANT SOURCE OF ENERGY REQUIRED FOR METABOLIC ACTIVITIES • THESE ARE POLYHYDROXY ALDEHYDES OR KETONES AND THEIR DERIVATIVES

  3. CLASSIFICATION

  4. MONOSACCHARIDES • ‘MONO’-ONE & ‘SAKCHARON’-SUGAR • SIMPLEST SUGAR-CANT HYDROLYZED FURTHER • SMALL CHAINS OF ALDEHYDES AND KETOSE • SWEET TASTING AND DISSOLVE IN WATER • SUBDIVISON OF MONOSACCHARIDE:- • TRIOSE: THREE C- ATOMS EG:-GLYCEROSE • TETROSE:FOUR C-ATOMS EG:-ERYTHROSE • PENTOSE:FIVE C-ATOMS EG:-RIBOSE • HEXOSE:SIX C-ATOMS EG:-GLUCOSE,FRUCTOSE

  5. OLIGOSACCHARIDE ‘OLIGO’-FEW & SACCHARIDE-SUGAR • COMPOUND SUGARS –YIELD 2-10 MOLECULES OF SIMPLE SUGARS • LOW GLYCEMIC INDEX CARBOHYDRATES • PRIMARLY FOUND IN LEGUMES • SUB DIVISION OF OLIGOSACCHARIDE:- • DISACCHARIDE:YIELDS 2 MOLECULES ON HYDROLYSIS EG:SUCROSE,LACTOSE,MALTOSE • TRISACCHARIDES:YIELDS 3 MOLECULES ON HYDROLYSIS EG:RAFFINOSE • TETRASACCHARIDE:YIELDS 4 MOLECULES ON HYDROLYSIS EG:STACHYOSE

  6. GLYCEMIC INDEX: GLYCEMIC INDEX MEASURES HOW FAST THE FOOD IS LIKELY TO RAISE OUR BLOOD GLUCOSE LEVEL • Carbohydrate that breakdown rapidly during digestion have the highest glycemic indices. such carbohydrate require less energy to be converted into glucose ,which results in faster digestion and a quicker increase in blood glucose • Carbohydrate that breakdown slowly releasing glucose gradually into blood stream,have a low glycemic index

  7. FACTORS INFLUENCES THE GLYCEMIC INDEX OF FOOD. • BIOCHEMICAL STRUCTURE OF CARBOHYDRATES-FOR EXAMPLE AMYLOPECTIN IS MORE READILY ABSORBED • RIPENESS-RIPE FRUITS AND VEGETABLES TEND TO HAVE MORE SUGAR THAN UNRIPE ONES,AND SO TEND TO HAVE A HIGHER GLYCEMIC INDEX • TYPE OF STARCH-SOME STARCH ARE EASIER TO BREAK INTO SUGAR MOLECULES THAN OTHERS-EG-STARCH IN POTATOES AND ABSORBED QUICKLY IN BLOOD STREAM • FAT CONTENT AND ACID CONTENT-THE MORE FAT OR ACID A FOOD CONTAINS,THE SLOWER ITS CARBOHYDRATE ARE CONVERTED TO SUGAR AND ABSORBED INTO THE BLOOD STREAM • PHYSICAL FORM-FINELY GROUND GRAIN IS MORE RAPIDLY DIGESTED AND SO A HIGHER GLYCEMIC INDEX

  8. WHY SHOULD WE EAT LOW GLYCEMIC INDEX FOOD? • CONTROL YOUR BLOOD GLUCOSE LEVEL • CONTROL YOUR CHOLESTROL LEVEL • CONTROL YOUR APPETITE • LOWE YOUR RISK OF GETTING HEART DISEASE • LOWER YOUR RISK OF GETTING TYPE2 DIABETES

  9. COMPARISON

  10. POLYSACCHARIDES • ‘POLY’-MANY & ‘SACCHARIDE’-SUGAR • COMPOUND SUGARS-YIELDS MORE THAN 10 MOLECULES OF SIMPLE SUGARS ON HYDROLYSIS • INSOLUBLE IN WATER • SUBDIVISON OF POLYSACCHARIDE:- • HOMPLOYSACCHARIDE:YIELDS SAME TYPE OF MONOSACCHARIDE UNITS EG:STARCH,GLYCOGEN • HETEROPOLYSACCHARIDE:YIELDS DIFFERENT TYPE OF MONOSACCHARIDE UNITS EG:HYALURONIC ACID

  11. STARCH • STARCH • STARCH IS STORAGE MOLECULE IN PLANTS • MADE UP OF AMYLOSE AND AMYLOPECTIN • AMYLOSE LINEAR COMPONENT OF STARCH.THE LINKAGE IN AMYLOSE IS α1 4 LINKAGE • AMYLOPECTIN BRANCH COMPONENT OF STARCH.THE LINKAGE IN AMYLOPECTIN IS α 1 4 AND α1 6

  12. GLYCOGEN • STORAGE MOLECULES IN ANIMALS AND IS OFTEN CALLED ‘ANIMAL STARCH’ • STORED IN THE LIVER AND MUSCLES OF ANIMALS • GLYCOGEN IS BRANCHED CHAIN POLYSACCHARIDE AND RESEMBLES AMYLOPECTIN IN STRUCTURE • IT IS HIGHLY BRANCHED AS COMPARE TO STARCH

  13. AMYLOSE • LINEAR COMPONENT OF STARCH.AMYLOSE CONSIST OF GLUCOSE UNITS LINKED TOGETHER BY α1 4 BONDS • THE CHAIN LENGTH OF AMYLOSE VARIES AND IT IS CONSIDERED TO HAVE AMOLECULAR WEIGHT OF1.1 TO 1.9 MILLIONS • AMYLOSE IS SOLUBLE IN WATER • CEREAL STARCHES USUALLY CONTAIN 25% AMYLOSE AND 75% AMYLOPECTIN • IT IS THE STRUCTURE OF AMYLOSE THAT IS RESPONSIBLE FOR THE BLUE COLOUR PRODUCED BY IODINE WITH STARCH • THE STRUCTURE OF AMYLOSE CONTRIBUTES TO THE GELLING CHARACTERSTICS OF COOKED AND COOL STARCHES

  14. AMYLOPECTIN • AMYLOPECTIN ALSO HAS THE BACKBONE OF α1 4 LINKAGE BUT IN ADDITION THE MOLECULE IS BRANCHED THROUGH α1 6 • THE LENGTH OF THE LINEAR UNIT IN AMYLOPECTIN IS ABOUT 20-25 GLUCOSE UNITS • AMYLOPECTIN HAS A BRUSHLIKE STRUCTURE AND ITS MOLECULAR WEIGHT IS OVER 10 MILLION • AMYLOPECTIN IS RESPONSIBLE FOR THICKENED PROPERTIES OF STARCH PREPARATION BUT IT DOES NOT CONTRIBUTE TO GEL FORMATION

  15. AMYLOSE AND AMYLOPECTIN

  16. FUNCTIONS OF CARBOHYDRATES • PROVIDING ENERGY AND REGULATION OF BLOOD GLUCOSE:-each gram of carbohydrate when oxidized yields approximately 4kcal of energy • SPARE THE USE OF PROTEINS FOR ENERGY:-when carbohydrates are not sufficient in our body to provide energy,protein breakdowwn itself to fullfill the requirement of carbohydrates • HELPING IN PREVENTING KETOSIS:-In the absence of adequate cho large amount of ketone bodies are produced.The accumulation of ketone bodies increases the acidity of blood

  17. GIVE BULK TO THE DIET:-carbohydrates give bulk to the diet. • ACT AS FLAVOURS AND SWEETNERS:-Different sygars vary in sweetness,fructose is twice sweet as sucrose and sucrose is 30% sweet than glucose • Carbohydrates are also important for the correct working of our brain, heart and nervous, digestive and immune systems.  • These act as intermediates in the biosynthesis of other basic biochemical entities

  18. ROLE IN MUSCLE: carbohydrates are the major source of energy for muscular work.during muscular contraction,glycogen is broken down to lactic acid through glycolysis • ROLE IN LIVER:these include detoxifying action and regulating influence of proteins and fat metabolism.liver is rich in glycogen and is more resistant to certain poisons such as carbon tetrachloride,alcohol ,arsenic and bacteria

  19. SOURCE OF ENERGY FOR HEART MUSCLE:the heart muscle mainly uses glucose as source of energy • SYNTHESIS OF RIBOSE TO GLUCOSE:it is formed in the body from glucose by hexose mono phosphate pathway • CONVERSION TO FAT:excess calories fed in the diet in the form of carbohydrate is stored as fat in adipose tissue

  20. IMPORTANCE OF VARIOUS CHO • LACTOSE • Lactose is the main source of energy supplied to new born mammalian in mother’s milk • Easily fermented to lactic acid ,by lactic acid bacteria(lactobacillus) ,while preparing curds and cheese • Helps in absorption of calcium and phosphorous • It triggers production set of genes in some bacteria

  21. STARCH • It is also used in the form of flakes, sticks, and pearls (tapioca and sago). • Starch in its basic refined form is used in cooking to thicken foods such as sauces, cabbages and many others. • In industry, it is used in the manufacturing of adhesives, paper, textiles and as a mold in the manufacture of sweets such as wine gums and jelly beans.  • Starch is huge part of our diet.our bodies breakdown starch into simple sugars which is then used for energy(ATP)

  22. DIETARY FIBRE(UNAVAILABLE CARBOHYDRATE) • Many Foods Contain Non-digestable Carbohydrates.These Non-digestable Carbohydrate Designated As “Dietary Fibre”or Unavailable Carbohydrates • It used to be believed that fibres could not be used by the human body, as the digestive juices in the body did not contain enzymes capable of breaking down these compounds. • It was overlooked that a part of the fibre is fermented by enzymes found in the micro-organisms of the large intestines.

  23. CLASSIFICATION .. SOLUBLE FIBRES ARE SOLUBLE IN WATER AND BECOME STICKY IN CONSISTENCY INSOLUBLE FIBRE DOESN’T DISSOLVE OR ABSORB WATER.IT PASSES THROUGH OUR DIGESTIVE SYSTEM IN CLOSE TO ITS ORIGINAL FORM

  24. IMPORTANCE OF FIBRE • Helps maintain bowel integrity and health. A high-fiber diet may lower your risk of developing hemorrhoids, and small pouches in your colon. • Lowers blood cholesterol levels. Soluble fiber found in beans, oats, flaxseed and oat bran may help lower total blood cholesterol levels by lowering low-density lipoprotein, or "bad," cholesterol levels.  • Helps control blood sugar levels. Fiber, particularly soluble fiber, can slow the absorption of sugar, which for people with diabetes can help improve blood sugar levels • Aids in weight loss. High-fiber foods generally require more chewing time, which gives your body time to register when you're no longer hungry, so you're less likely to overeat.

  25. RESISTANT STARCH • SMALL INTESTINE IS UNABLE TO DIGEST,LIMITED DIGESTION IN LARGE INTESTINE • PORTION OF STARCH THAT IS NOT BROKEN BY HUMAN ENZYMES • CLASSIFICATION:- • RS 1:TRAPPED IN CELLS(SEEDS & LEGUMES) • RS2:NATIVE STARCH(RAW POTATOES,BANANAS) • RS3:CRYSTALLINE,NON-GRANULAR STARCH (COOKED POTATOES) • RS4:CHEMICALLY MODIFIED • 20gms OF RESISTANT STARCH EATEN EVERY DAY • BENEFITS TO PEOPLE WHO ARE TRYING TO REDUCE WEIGHT • INCREASE STOOL BULK,ACTING AS A MILD LAXATIVE

  26. COMPOSITION OF CARBOHYDRATE SUGARS

  27. METABOLISM OF CARBOHYDRATES • DIGESTION • ABSORPTION • UTILIZATION

  28. DIGESTION AND ABSORPTION • DIGESTION IN ORAL CAVITY ACTION OF SALIVA: • FOOD MIXES WITH SALIVA • SALIVA CONTAINS SALIVARY AMYLASE(PTYALIN) • PTYALIN CONVERTS STARCH INTO MALTOSE,ISOMALTOSE AND DEXTRINS • 30% STARCH HYDROLYSED HERE salivary amylase STARCH MALTOSE ISOMALTOSE α-DEXTRINS

  29. ACTION OF PANCREATIC JUICE • PANCREATIC JUICE CONTAINS DIGESTIVE ENYME CALLED PANCREATIC α-AMYLASE • α- AMYLASE CONVERTS STARCH INTO MALTOSE,ISOMALTOSE AND DEXTRINS pancreatic STARCH MALTOSE ISOMALTOSE α-DEXTRINS amylase

  30. ACTION OF INTESTINAL JUICE • INTESTINAL JUICE CONTAINS MALTASE,ISOMALTASE,SUCRASE,DEXTRINASE,LACTASE WHICH ACT AS FOLLOWS:- MALTASE MALTOSE 2GLUCOSE

  31. ISOMALTASE 2GLUCOSE ISOMALTOSE SUCROSE GLUCOSE FRUCTOSE SUCRASE GLUCOSE GALACTOSE LACTASE LACTOSE α- DEXTRINASE α- DEXTRINS GLUCOSE

  32. ABSORPTION • Once digestion is essentially finished, waste products leave the ileum with the help of fiber, and these solids then enter the large intestine (the colon). • In the colon, water is reabsorbed; some nutrients are produced by friendly bacteria (vitamin K, biotin, vitamin B 12 ); fibers are digested to various acids and gases; and minerals, such as potassium and sodium, are reabsorbed (when needed). Any fiber that is not broken down—and small amounts of other undigested products—are excreted in the feces.

  33. UTILIZATION (CONT…) • GLYCOLYSIS: • SEQUENCE OF REACTION THAT CONVERTS ONE GLUCOSE TO 2 MOLECULES OF PYRUVATE • TAKES PLACE IN CYTOPLASM • ITS BOTH AEROBIC AND ANAEROBIC • ATP YIELD-8ATP FORMED • IT HAS 2 PHASE PREPARATORY AND PAY OFF • OCCURS IN PROKARYOTES AND EUKARYOTES

  34. GLYCOLYSIS

  35. FATE OF PYRUVATE THREE IMPORTANT ROUTES TAKEN BY PYRUVATE AFTER GLYCOLYSIS: (a)In Some Microorganisms Pyruvate Form From Glucose Is Transform Anaerobically Into Ethanol And CO2 A Process Called ALCOHOLIC FERMENTATION (b)The supply of oxygen is insufficient, pyruvate cant be oxidized further .Under such conditions it is then reduced to lactate (ANAEROBIC GLYCOLYSIS (c)Pyruvate so formed enters mitochondria where it is oxidized,to form the acetylCoA (a) (b) (c)

  36. KREB CYCLE: • DISCOVERED BY ‘HANS KREB’ • ALSO CALLED TCA CYCLE(TRICARBOXYLIC ACID) • IT TAKES PLACE IN MITOCHONDRIA PROCESS: • OXIDATION OF PYRUVATE TO ACETYLY-COA:-PYRUVATE ENTERS MITOCHONDRIA THROUGH TRANSPORT PROTEIN • UNDER GOES OXIDATIVE DECARBOXYLATION TO PRODUCE CO2 AND NADH • ACETLY-COA FUNCTION AS SUBSTRATE ENTRANT FOR KREB CYCLE

  37. GLUCONEOGENESIS SYNTHESIS OF GLUCOSE FROM NON-CARBOHYDRATE PRECURSORS • It occurs mainly in liver • Synthesis of glucose from pyruvate utilizes many of the same enzymes as glycolysis • PRECURSORS OF GLUCONEOGENESIS • Lactate,pyruvate,glycerol • Citric acid • Some amino acids

  38. IMPORTANCE • Brain ,central nervous system,erythrocyte,kidney are dependent on glucose for continous supply of energy. Human brain require 120g energy per day and about 160g needed by the entire body • Glucose is the only source that supplies energy to skeltal muscle, under anaerobic conditions

  39. GLUCOGENETIC PATHWAY • Although glycolysis and gluconeogenesis share several steps but these pathways are not simple the reverse of each other. • During gluconeogenesis seven steps are catalyzed by the same enzyme used in glycolysis,three are reversible • Conversion of glucose-6-phosphate by hexokinase • Conversion of fructose-6-phosphate to fructose 1:6 biphosphate • Conversion of phosphoenol pyruvate to pyruvate by pyruvate kinase

  40. GLUCONEOGENESIS PATHWAY

  41. DISSACCHARIDE DEFICIENCY • LACTOSE INTOLERANCE (HYPOLACTASIA) • LACK OF THE ENZYME LACTASE CAUSES INABILITY TO DIGEST LACTOSE IN MILK PRODUCTS • THERE ARE FEW WITH COMPLETE INTOLERANCE,MOST CAN INGEST SMALL QUANTITIES OF MILK PRODUCTS • SOME PEOPLE ARE REALLY ALLERGIC TO MILK.THIS ALLERGY SEEMS TO BE INCREASING IN AN INFANT • PREMATURE BABIES SOME TIMES HAVE LACTOSE INTOLERANCE.CHILDREN WHO BORN AT FULL TERM USUALLY DO NOT SHOW SIGNS OF LACTOSE INTOLERANCE UNTIL THEY ARE THREE YEARS OLD • BIG PROBLEM-CALCIUM DEFICIENCY

  42. CAUSES:- • BOWEL SURGERY • INFECTION FROM SMALL INTESTINE FROM VIRUSES OR BACTERIA,WHICH MAY DAMAGE THE CELLS(MOST OFTEN IN CASE OF CHILDREN) • INTESTINAL DISEASE SUCH AS CELIAC SPRUE SYMPTOMS • ABDOMINAL BLOATING • ABDOMINAL CRAMPS • DIARRHOEA • FLATULENCE • NAUSEA • SLEEPLESSNESS

  43. TREATMENT: • DECREASING OR REMOVING MILK PRODUCTS FROM THE DIET USUALLY IMPROVES THE SYMPTOMS • PEOPLE WITH LOW LACTASE CAN DRINK 2-4 OUNCES OF MILK AT ONE TIME • SOME OF THE MILK PRODUCTS ARE EASIER TO DIGEST:- • BUTTERMILK AND CHEESES • FERMENTED MILK PRODUCTS(YOGHURT) • ICE CREAMS,MILKSHAKES • LACTOSE FREE MILK,MILK PRODUCTS

  44. COGENITAL SUCRASE- ISOMALTASE DEFICIENCY • Autosomal inherited error of metabolism in which patients are born with absent or low level of 2 digestive enzymes :SUCARSE AND ISOMALTASE • Sucrase is the intestinal enzyme that aids in breakdown of sucrose into glucose and fructose which are used by the body as fuel • Isomaltase is one of the several enzyme that helps to digest starch

  45. SYMPTOMS: • VOMITING • WATERY DIARRHEA • COLIC • FATIGUE • DEHYDRATION • ABDOMINAL CRAMPS

  46. FRUCTOSE MAL-ABSORPTION • Fructose Malabsorption Disorder, logically, is the inability to absorb fructose (which is the sugar which occurs naturally in many foods – mostly fruit).

  47. SYMPTOMS: • Bloating(from small intestine to large intestine) • Diarrhea or constipation • Flatulence • Vomiting • OTHER SYMPTOMS INCLUDE: • Aching eyes • Fuzzy head • Fatigue

More Related