REACTIONS OF DISACCHARIDES

-

 

REACTIONS OF DISACCHARIDES

 

                Disaccharides are obtained by the combination of two mono saccharides by a glycosidic linkage. On treatment with hot acids or with enzymes the disaccharides can be hydrolysed to the constituents monosaccharides, examples of commonly used disaccharides and their constituent monosaccharides are given below.

 

Sucrose :               Sweetening sugar (Cane Sugar) - Glucose + fructose

                                (Aldehydic group of glucose is linked with keto group of fructose.)

 

Lactose :               Milk sugar = Glucose + Galactose

                                (Aldehydic group of galactose is linked with alcoholic group of glucose(4c).

 

Maltose                 :               Malt sugar = Glucose + Glucose. Aldehydic group of glucose is

                                linked with alcoholic group of glucose (4c).

 

Maltose is obtained in hydrolysis of starch and other polysaceharides.

 

Maltose and lactose are reducing sugars, where as sucrose is non redcuing sugar.

 

Perform the following tests with lactose, maltose and sucrose.

 

(1) Molisch test (2) Seliwanoff’s test (3) Barfoed’s test (4) Fehling’s test. (5) Benedict’s test (6) Inversion test, (For sucrose only).

 

Acid Hydrolysis:

                To 5ml of sucrose solution add 5 drops of conc HCl boil for a minute and cool. Neutralize the hydrolysed sample with 40% sodium hydroxide and perform Fehling’s test on it. Write your inference

Comments

Post a Comment

Popular posts from this blog

Chemical test for Tragacanth

-
Chemical test for Tragacanth Organoleptic test: Appearance: Crystalline                                                          tragacanth Colour: White or faint yellow                                                 tragacanth Odour: None                                                                           tragacanth Taste: Mucilaginous                                                                tragacanth Solubility: Insoluble in alcohol, partially soluble in water      tragacanth Chemical test: SI.No. Test Observation Inference 1. To 4ml of 0.5%w/v solution add  0.5ml of HCl and heat for 30minutes on water bath Divide the hydrolyzed product in 2 parts a)       1 st part=Add 1.5ml of NaOH solution to neutralize and add Fehling’s solution A and B in equal quantities(mixed before) and warm over water bath. b)       2 nd part= Add barium chloride solution Red ppt o
Read more

MINOR DISORDERS OF NEW BORN AND ITS MANAGEMENT - NURSING ASSIGNMENT

-
INTRODUCTION         Neonatal health problems are frequently found ranging from minor physical or physiological peculiarities to the serious life threatening illnesses. Minor problems should not be ignored lightly without adequate assessment of the conditions. Early diagnosis and management of the serious problems help to overcome life long disability and to reduce neonatal morbidity and mortality. Nurses are responsible to manage the minor problems and to detect the serious problems for early and prompt management along with appropriate nursing interventions and support to the mother. MINOR DISORDERS OF NEW BORN 1. VOMITING         Vomiting is one of the common manifestations in the neonates. Regurgitation after feeds should not be confused with vomiting. Mucus vomiting often hinged with blood is quite common soon after birth. It is due to irritation often gastric mucosa by the swallowed materials during birth. Causes: ·         Dietic ·         Over feeding
Read more

KANGAROO CARE - NURSING ASSIGNMENT

-
INTRODUCTION         Caring low birth weight baby is a great challenge for the neonatal care unit and the family. Number of low birth weighs baby is still for beyond the expected target in our country. The cost of the quality management of these babies is increasing day by day. Kangaroo care is low cost approach for the care of low birth weight baby. This method of care was introduced and popularized by Dr.Edger Ray, Dr.Martinez and Dr.Charpak in late 1970s. DEFINITION         Kangaroo Mother Care (KMC) is a special way of caring low birth weight infants by skin to skin contact if promotes their health and welling by effective thermal control, breast feeding and bonding. KMC is initiated in hospital and continued at home. COMPONENTS OF KMC         In KMC, the infant is continuously kept in skin contact by the mother and breastfed exclusively to the utmost extent.         The two components of KMC are; 1.    Skin to skin contact is provi
Read more