US3622453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing l-threonine
Assignee: KH Neochem Co Ltd
•
Filing: 1968-09-09
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Granted: 1971-11-23
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Expires: 1988-09-09
Abstract
Abstract A process for producing L-threonine by fermentation which comprises culturing a micro-organism capable of producing Lthreonine under aerobic aqueous in an equeous nutrient medium containing an antibiotic, for example, streptomycin. The addition of the antibiotic makes it possible to accumulate large yields of L-threonine in the culture liquor and prevents the conversion and disappearance thereof.
Inventors
- 👤 Katsumi Akeyama
- 👤 Katsuya Nasu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:06
CPC Classifications
C; C12; C12P; C12P13/00; C12P13/04; C12P13/08; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/848; Y10S435/849
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
26 words
The process of claim 1, wherein said antibiotic is selected from the group consisting of streptomycin, dihydrostreptomycin, chloramphenicol, tetracycline, oxytetracycline, chlorotetracycline, kanamycin, polymyxin B and viomycin.
Claim 2
Dependent Claim
67 words
A process for producing L-threonine which comprises culturing a microorganism capable of producing L-threonine and belonging to Escherichia coli under aerobic conditions in an aqueous nutrient medium containing at least one antibiotic, said antibiotic being added to the medium after the growth of said microorganism but before substantial metabolism of the produced L-threonine has begun, accumulating L-threonine in the resultant culture liquor, and recovering said L-threonine therefrom.
Claim 3
Dependent Claim
26 words
The process of claim 3, wherein said antibiotic is selected from the group consisting of streptomycin, dihydrostreptomycin, chloramphenicol, tetracycline, oxytetracycline, chlorotetracycline, kanamycin, polymyxin B and viomycin.
Claim 4
Dependent Claim
27 words
The process of claim 3, wherein said antibiotic is added to the medium before the produced L-threonine in the culture liquor undergoes conversion and begins to disappear.
Claim 5
Dependent Claim
27 words
The process of claim 3, wherein said antibiotic is added to the medium within the time period of 8 to 72 hours after the initiation of culturing.
Claim 6
Dependent Claim
10 words
The process of claim 3, wherein said antibiotic is streptomycin.
Claim 7
Dependent Claim
21 words
The process of claim 7, wherein the amount of streptomycin added to the medium is 10-300 mg. per liter of medium.
Claim 8
Dependent Claim
22 words
The process of claim 3, wherein the amount of antibiotic added to the medium is 10-1,000 mg. per liter of the Medium.
Claim 9
Dependent Claim
17 words
The process of claim 3, wherein said antibiotic is added to the medium all at one time.
Claim 10
Dependent Claim
14 words
The process of claim 3, wherein said antibiotic is added to the medium intermittently.
Claim 11
Dependent Claim
28 words
The process of claim 3, wherein culturing is carried out at a temperature of about 20* to 40* C. and at a pH of about 5 to 8.
Claim 12
Dependent Claim
74 words
A process for producing L-threonine which comprises culturing a microorganism selected from the group consisting of Escherichia coli ATCC 21148, Escherichia coli ATCC 21272 and Escherichia coli ATCC 21149 in an aqueous nutrient medium containing at least one antibiotic, said antibiotic being added to the medium after the growth of said microorganism but before substantial metabolism of the produced L-threonine has begun, accumulating L-threonine in the resultant culture liquor, and recovering said L-threonine therefrom.
Claim 13
Dependent Claim
26 words
The process of claim 13, wherein said antibiotic is selected from the group consisting of streptomycin, dihydrostreptomycin, chloramphenicol, tetracycline, oxytetracycline, chlorotetracycline, kanamycin, polymyxin B and viomycin.
Claim 14
Dependent Claim
27 words
The process of claim 14, wherein said antibiotic is added to the medium within the time period of 8 to 72 hours after the initiation of culturing.
Claim 15
Dependent Claim
28 words
The process of claim 13, wherein culturing is carried out at a temperature of about 20* to 40* C., and at a pH of about 5 to 8.
Claim 16
Dependent Claim
10 words
The process of claim 16, wherein said antibiotic is streptomycin.
References Cited (Backward Citations)
US2937122A
Cited
US3080297A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |