Method for stabilization of aqueous acrylamide solution

1. A method for preventing polymerization of an aqueous acrylamide solution during preservation and/or transportation of the acrylamide solution comprising:

adding a microbial cell having nitrile hydratase activity to the aqueous acrylamide solution at a dried cell weight concentration of 1 to 14000 mg/L, wherein the microbial cell having nitrile hydratase activity is selected from the group consisting of Rhodococcus rhodochrous, Escherichia coli MT-10822 (Accession number: FERM BP-5785), and mixtures thereof, and

preserving and/or transporting the acrylamide solution in the presence of the microbial cell,

wherein the presence of the microbial cell in the acrylamide solution prevents polymerization of the aqueous acrylamide solution.

2. The method according to claim 1 , wherein the dried cell weight concentration is 10 to 14000 mg/L.

3. The method according to claim 1 , wherein the Rhodococcus rhodochrous is selected from the group consisting of Rhodococcus rhodochrous J-1 (Accession number: FERM BP-1478), Rhodococcus rhodochrous M8 (Accession number: VKPMB-S926), and mixtures thereof.

4. The method according to claim 1 wherein the microbial cell is added at the time of preparation of the aqueous acrylamide solution from an aqueous acrylonitrile solution.

5. The method according to claim 1 , wherein the nitrile hydratase activity is an activity which produces an acrylamide from an acrylonitrile.

6. The method according to claim 1 , wherein the acrylamide has been produced from an acrylonitrile using the microbial cell having nitrile hydratase activity.

7. The method of claim 1 , wherein the microbial cell is added after preparation of the aqueous acrylamide solution.

8. A method for reducing foamability of an acrylamide solution during transportation, concentration, distillation, and/or crystallization of the acrylamide solution comprising:

adding a microbial cell having nitrile hydratase activity to the aqueous acrylamide solution at a dried cell weight concentration of 500 mg/L or lower, and

transporting, concentrating, distilling, and/or crystallizing the acrylamide solution in the presence of the microbial cell,

wherein the microbial cell having nitrile hydratase activity is selected from the group consisting of Rhodococcus rhodochrous, Escherichia coil MT-10822 (Accession number: FERM BP-5785), and mixtures thereof, and

wherein the presence of the microbial cell in the acrylamide solution reduces foamability of the aqueous acrylamide solution.