Disaccharides, Biology

DISACCHARIDES

  • They are oligosaccharides composed of two monosaccharide residues .
  • Three common disaccharides are   sucrose (glucose + fructose) = cane suger maltose (glucose + glucose) = malt sugar lactose (glucose + galactose) = milk sugar
  • Common formula is Cn(H2O)n-1.

SUCROSE

  • Commercial or Table sugar.
  • Obtained from stems of Sugarcane (Saccharum officinarum) and roots of Beet sugar (Beta vulgaris).
  • Sucrose is a non-reducing sugar.
  • Sweetness index of sucrose is 100.
  • Formed of two molecules each of glucose and fructose.
  • It has neither aldehyde group nor keto group.

MALTOSE

  • Malt Sugar
  • It is a disaccharide formed of two molecules of glucose which are connected to each other through the a -1, 4 D-glycosidic linkage.
  • It is present in Barley.
  • Maltose is formed during hydrolysis of starch.
  • It is found in germinating cereals.
  • The sugar is present in malt, and is therefore, also called malt sugar.
  • Sweetness index is 30.
  • Maltose is a reducing surgar.

LACTOSE

  • Milk Sugar.
  • It is a disaccharide sugar present in milk upto the extent of 5%.
  • Lactose is formed of D-galactose and D-glucose, both in pyranose state, through the b-1, 4 glycocydic bond.
  • The monosaccharide galactose is also synthesised from glucose inside the mammary glands.
  • Sweetness index of lactose is 16.
  • Like maltose, lactose is a reducing sugar.
  • Souring of milk occurs when bacteria convert lactose into lactic acid.
  • Present only in mammals.

TREHALOSE

  • It is a disaccharide sugar made of two glucose residues which was originally obtained from cocoon of Trehela (weevil Larinus species) as sweetening agent.
  • Trehalose is found in haemolymph of some insects and fungi including yeast.
Posted Date: 10/9/2012 3:37:03 AM | Location : United States







Related Discussions:- Disaccharides, Assignment Help, Ask Question on Disaccharides, Get Answer, Expert's Help, Disaccharides Discussions

Write discussion on Disaccharides
Your posts are moderated
Related Questions
Signify the term Metacoel. The last of three coelomic spaces found in tripartate body plan characteristic of deuterostome lineage of animals. Other coelomic compartments are th

EFFECT ON BODY - 1 .       CANCER - Benzpyrene present in tobacco is carcinogenic , responsible for lung cancer. Tobacoo chewing also produce oral cancer. Smoking m

Botulism Botulism is a rapidly fatal motor paralysis. It is caused by ingestion of toxin of Clostridium botulinum in food. Many species of domesticated, wild animals and birds

Explain Potts Shunt in palliative operations ? This is a similar shunt done through a left thoracotomy. Anastomosis is done between left pulmonary artery aid descending thoraci

Q. Number of risk factors of gout? A number of risk factors are related to the development of hyperuricemia and gout. These factors include: • Hereditary: Genetics may play

Ways to adapt to stress Now that you know the nature of stress, let us see what type of strategies plants have acquired to adapt to stress. You know that biological functions

Q. False Positive ST Changes? 1) The slope of the PQ-segment can help predict the magnitude of the influence of P-wave depolarization and thus help predict which patient wou

Explain about the Complete proteins? We now know that proteins are composed of amino acids and that proteins differ in their amino acid make-up. Proteins lacking in one or more

The introns are the portions of genomic DNA which are transcribed (and hence present in the primary transcript) but are then spliced out later. They therefore are not present in th

USES OF DRUGS - 1.       Drugs are prescribed as medicines to prevent or cure a variety of diseases. 2.       May be used to promot physical and mental health. 3.       U