Method of culturing a microorganism under controlled agitation and aeration conditions

Patent metadata

Field	Value
Publication number	US-9701990-B2
Application number	US-66201505-A
Country	US
Kind code	B2
Filing date	Sep 5, 2005
Priority date	Sep 6, 2004
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A method of culturing a microorganism capable of producing at least any one of a highly unsaturated fatty acid or a compound containing a highly unsaturated fatty acid as a constituent fatty acid in a culture medium containing at least a carbon source and a nitrogen source, using an aeration-agitation culture device capable of adjusting and controlling an agitation power and an aeration amount. The method comprises the steps of performing mechanical agitation for a predetermined time after start of culture, where the agitation power per unit liquid amount is 269 (W/m 3 ) or less, and after the predetermined time has passed, adjusting and controlling at least any one of the maximum aeration amount and a maximum power required for agitation to a range which satisfies that KLA (=(P/V) 0.95 Vs 0.67 ) is 59 or more, an air flow rate parameter Vs 0.67 is 0.075 or more, and a required agitation power parameter (P/V) 0.95 is 203 or more, where P represents power required for agitation (W), V represents a liquid amount (m 3 ), and Vs represents an air flow rate (m/sec).

First claim

What is claimed is:

1. A method of producing a highly unsaturated fatty acid by culturing a strain of Mortierella alpina capable of producing the highly unsaturated fatty acid in a culture medium containing at least a carbon source and a nitrogen source, using an aeration-agitation culture device capable of adjusting and controlling an agitation power and an aeration amount, the method comprising:
performing mechanical agitation after start of a main culture, wherein the agitation power per unit liquid amount is 30-269 (W/m 3 )thereby promoting a transformation of M. alpina cells from a form of a pulp-shaped hypha to a pellet-shaped form, and wherein the main culture is started by inoculating a seed culture; and
immediately before dissolved oxygen concentration value decreases to about 50% or 12 to 24 hours after start of the main culture, increasing aeration or agitation by adjusting and controlling at least any one of the maximum aeration amount and a maximum power required for agitation to a range which satisfies that KLA (=(P/V) 0.95 Vs 0.67 ) is 59-282, an air flow rate parameter Vs 0.67 is 0.075-0.191, and a required agitation power parameter (P/V) 0.95 is 282-2169, where P represents power required for agitation (W), V represents a liquid amount (m 3 ), and Vs represents an air flow rate (m/sec),

thereby producing the highly unsaturated fatty acid from the main culture.

2. The method according to claim 1 , wherein the highly unsaturated fatty acid is arachidonic acid.

3. A method of producing a compound containing a highly unsaturated fatty acid by culturing a strain of Mortierella alpina capable of producing the compound containing the highly unsaturated fatty acid in a culture medium containing at least a carbon source and a nitrogen source, using an aeration-agitation culture device capable of adjusting and controlling an agitation power and an aeration amount, the method comprising:
performing mechanical agitation after start of a main culture, wherein the agitation power per unit liquid amount is 30-269 (W/m 3 ) thereby promoting a transformation of M. alpine cells from a form of pulp-shaped hypha to a pellet-shaped form, and wherein the main culture is started by inoculating a seed culture; and
immediately before dissolved oxygen concentration value decreases to about 50% or 12 to 24 hours after start of the main culture, increasing aeration or agitation by adjusting and controlling at least any one of the maximum aeration amount and a maximum power required for agitation to a range which satisfies that KLA (=(P/V) 0.95 Vs 0.67 ) is 59-282, an air flow rate parameter Vs 0.67 is 0.075-0.191, and a required agitation power parameter (P/V) 0.95 is 282-2169, where P represents power required thr agitation (W), V represents a liquid amount (m 3 ), and Vs represents an air flow rate (m/sec),

thereby producing the compound containing the highly unsaturated fatty acid from the main culture.

4. The method according to claim 3 , wherein the highly unsaturated fatty acid is arachidonic acid.

5. The method according to claim 1 , wherein (P/V) 0.95 is in the range of 282-2169 and Vs 0.67 is in the range of 0.075-0.191 after increasing aeration or agitation.

6. The method according to claim 1 , wherein (P/V) 0.95 is in the range of 282-2169 and KLA (=(P/V) 0.95 Vs 0.67 ) is in the range of 59-282 after increasing aeration or agitation.

7. The method according to claim 3 , wherein (P/V) 0.95 is in the range of 282-2169 and Vs 0.67 is in the range of 0.075-0.191 after increasing aeration or agitation.

8. The method according to claim 3 , wherein (P/V) 0.95 is in the range of 282-2169 and KLA (=(P/V) 0.95 Vs 0.67 ) is in the range of 59-282 after increasing aeration or agitation.

Assignees

• Higashiyama Kenichi
• Nippon Suisan Kaisha Ltd

Inventors

• Higashiyama Kenichi

Classifications

• C12N1/14 Primary

  Fungi (culture of mushrooms A01G18/00; as new plants A01H15/00); Culture media therefor · CPC title

• C12P7/6427

  Polyunsaturated fatty acids [PUFA], i.e. having two or more double bonds in their backbone · CPC title

• C12P7/6472 Primary

  containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone · CPC title

• C12P7/64

  Fats; Fatty oils; Ester-type waxes; Higher fatty acids, i.e. having at least seven carbon atoms in an unbroken chain bound to a carboxyl group; Oxidised oils or fats · CPC title