NUCLEIC - SUMMARY

• MATERIALS

  Watch glass

  Cheese cloth

  Filter pape
• REAGENTS

  5% ammonium molybdate

  0.1% ribose solution

  0.1% glucose

  Bial Orcinol reagent

  10% NH4OH

  5% AgNO3

  Yeast

  White sand

  0.2% NaOH

  10% NaOH

  1% CuSO4

  10% H2SO4

  10% HNO3
• identifying reagent

  nucleoprotein - 10% NaOH and 1% CuSO4

  mild acid hydrolysis - 10% H2SO4

  inorganic phosphates - NH3, 10% HNO3, 2 mL ammonium molybdate

  ribose - 0.1% ribose sol and 0.1% glucose sol

  purine - 10% NH4OH and 5% AgNO3
• results

   test for nucleoproteins (filtrate from yeast RNA) - White precipitate forms upon adding acetic acid and lead acetate solution.

  • Presence of nucleoproteins (indicates protein-nucleic acid complexes).

  b. test for purine bases (acid hydrolysate) - Formation of a yellow crystalline precipitate upon adding ammonium molybdate and concentrated HCl.

  • Indicates the presence of purine bases (e.g., adenine, guanine).
• c. test for ribose (acid hydrolysate) - Blue-green color develops when treated with Bial’s reagent (a mixture of orcinol, hydrochloric acid, and ferric chloride).

  • Presence of ribose (a pentose sugar).

  -0.1% ribose - Formation of a blue-green color when treated with Bial’s reagent.

  • Confirms the presence of ribose (pentose sugar).

  -0.1% glucose - No characteristic color change with Bial’s reagent (remains light yellow or brown).

  • Indicates the absence of ribose, confirming glucose (a hexose sugar).
• d. test for phosphates (acid hydrolysate) - Formation of a yellow precipitate when treated with ammonium molybdate in an acidic solution.

  • Indicates the presence of phosphate groups.