Benedict test pptx. Qualitative test for reducing sugars

🍎 Benedict's Test 🧪
Benedict's test is a common chemical test used to check for the presence of reducing sugars (simple carbohydrates) in a given sample.

1. Qualitative test for reducing sugars Benedict test Roll no. - 5220 Name - Kusum Sahu Class - Bsc 3rd sem Subject - Microbiology practical assignment (DSC)

2. CONTENT Object Required material Principle Preparation of benedict reagent Procedure Observation table Result Precautions

3. • Object :- To detect the presence of reducing sugar in the given solution by Benedict reagent.

4. •Required Materials — Benedict reagent (copper sulphate solution mixed with sodium citrate and sodium carbonate) Test tube 🧪 Test tube holder Boiling water or bunsen burner Pipette or dropper Sugar solution to be tested

5. Principle :- Sodium carbonate in the Benedict reagent increases the pH of the sample-reagent solution mixture. Under warm alkaline conditions reducing sugars are tautomerism to strong reducing agents, enediols. These enediols reduce the cupric ions (Cu2+) (present as Copper Sulfate (CuSO4)) of Benedict reagent into cuprous ions (Cu+). The cuprous particles are present in form of insoluble Copper (I) oxide or cuprous oxide (Cu2O) which is of red color. These red-colored copper oxides get precipitated.

6. Reaction of benetict test

7. The concentration of reducing sugar in the sample differs from the intensity and shade of the color of the reaction mixture. This shade of color can be used to estimate the concentration of reducing sugar in the sample. Color may vary from greenish to yellow to orange-red to brick-red. As the concentration of reducing sugar increases color gradually changes from greenish to yellowish to orange to brick-red.

8. Measure 17.3 grams of copper sulfate (CuSO4), 173 grams of sodium citrate (Na3C6H5O7), and 100 grams of anhydrous sodium carbonate (Na2CO3) (or 270 grams of sodium carbonate decahydrate (Na2CO3.10H2O)) Put all the measured chemicals in a volumetric flask of 1000 mL. Pour distilled water up to 1000 mL marking. Dissolve all the components properly by shaking gently. Preparation of benedict reagent:-

9. •Procedure — Taken 1-2 ml of the given sugar solution in test tube. Now add 5ml of benedict reagent to the test tube Heat the mixture gently in a boiling water bath or on a bunsen burner for 2-3 minutes. Let the solution coll down. Obsei any colour change If a colour chy from blue to green, yellow, orange,brick red it indicates the prepare of a reducing sugar.

10. •Observation table Sample Observation S.No. 1) 2) Sample A(Glucose) Sample B ( Sucrose) Brick red ppt No colour change remains blue •Result Sample A :- Glucose is a reducing sugar ( test positive) Sample B :- sucrose is non reducing s( test negative) ugar

11. Precautions Measurement must be accurate. Don’t heat the mixture quickly. It is best to heat over a water bath slowly. During heating the solution, use a test-tube holder. Don’t face the test tube towards oneself or others during heating. Heating should be done at least thrice before reporting negative

12. Thank you