تفاعل #663667

معادلة التفاعل

N-acetylneuraminate

N-acetylmannosamine

sodium pyruvate

N-acetylmannosamine

sodium pyruvate

→

N-acetylneuraminic acid

المردود 39.8%

المذيبات

water

water

water

ظروف التفاعل

المعالجة

1. 1
   أخرىThe enzyme bag was removed
2. 2
   أخرىreused for new batch of reaction
3. 3
   غسيلThe resin was then washed with water (300 ml)
4. 4
   غسيلeluted with 0.5M HCOOH solution
5. 5
   أخرىThe eluate was collected
6. 6
   أخرىvacuum evaporated to dryness
7. 7
   workup.DISSOLUTIONThe residue was dissolved in water (2 ml)
8. 8
   workup.ADDITIONthen diluted with glacial acetic acid (10 ml) at 4° C. overnight
9. 9
   ترشيحfiltered the crystals
10. 10
    غسيلwashed with EtOH
11. 11
    أخرىdried

الإجراء التجريبي

To a pH 7.0˜7.5 solution of N-acetylmannosamine (2.7 g, 12.2 mmole) and sodium pyruvate (2.7 g, 24.5 mmole) in water (15 ml) was added a dialysis bag (cut off MW of 20,000) containing N-acetylneuraminate lyase [EC 4.1.3.3] (25 units) in a reaction mixture of N-acetylmannosamine (0.54 g) and sodium pyruvate (0.54 g) in water (3 ml) at pH 7.0-7.5. The reaction mixture was shaken at 60 r.p.m. at 30° C. for 5 days. The enzyme bag was removed and reused for new batch of reaction. The reaction mixture was diluted with water (15 ml), then passed through a column of Amberlite IRA-400 (HCOO− form) (150 ml). The resin was then washed with water (300 ml), eluted with 0.5M HCOOH solution. The eluate was collected and vacuum evaporated to dryness. The residue was dissolved in water (2 ml) then diluted with glacial acetic acid (10 ml) at 4° C. overnight, filtered the crystals, washed with EtOH, dried to afford N-acetylneuraminic acid as white crystalline powder (1.5 g, 39.8%).

المصدر