JPH0424988B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing propionic acid. (Object of the Invention) As a result of various studies on the production method of propionic acid using methanol as a carbon source, the present inventors found that
We discovered that microorganisms belonging to the genus Candeita have the ability to convert methanol to propionic acid,
We have arrived at the present invention. That is, the gist of the present invention is to culture a microorganism belonging to the genus Candida and having the ability to produce propionic acid using methanol as a carbon source,
A method for producing propionic acid characterized by obtaining propionic acid from a culture. (Structure of the Invention) The present invention will be described in detail below. The microorganism used in the present invention belongs to the genus Candida and has the ability to produce propionic acid, such as Candida boidinii A-1917-
3 (Feiko Kenboku No. 7853). This strain was isolated from soil,
Its mycological properties are as follows. Growth status in each medium (1) Growth status in YM liquid medium, 30°C, 3 days. Growth is good and a ring-shaped film is formed on the surface of the culture solution. A precipitate forms at the bottom of the culture solution. (2) Properties on YM plate agar Growth is good when cultured at 30℃ for 3 days. Colonies are buttery and white in color. The colony surface is smooth; the periphery is entirely to slightly wavy, and the ridges are plate-shaped; it exhibits a luminous luster. Cell morphology is oval to oval, size 2-10.3×1.3-
3.3 (average 3.6 x 2.5) μm, growth mode is multipolar budding, forming pseudohyphae. Ascospores are not formed. (3) Liquid medium containing 1.5% methanol, 30℃, 3
Daily growth status. Growth is good and almost no film is formed on the surface of the culture solution. A small amount of precipitate will form at the bottom of the culture solution. Physiological properties Growth range: pH 2-9; does not grow at temperatures of 10-30°C and 37°C. Assimilation of nitrate: Yes Gelatin liquefaction ability: No Production of starch-like substances: No Growth on 50% glucose (YM): No NaCl tolerance: 8-9% Methanol assimilation: Yes Pectin assimilation: Yes Vitamin requirements Characteristic: biotin pantothenic acid-
Ca

【table】

【table】

[Table] Identification at the genus level This strain (A-1917-3) does not produce carotenoid pigments, always forms pseudohyphae, grows by multipolar budding, and does not form ascospores. “The East” (2nd edition/
Candida (1970)
It was found that it belongs to the genus). Species identification Lee & Komagata (1980)
“Taxonomical study of methanol−
According to the genus Candeida, there are five species of methanol-assimilating bacteria (C.boidinii, C.cariosilignicola, C.
lipolytica, C. succiphila, C. utilis). These five types are mainly distinguished by their saccharide fermentability patterns and saccharide assimilation patterns. The saccharide fermentability test of this strain (A-1917-3) and the carbon source assimilation pattern described above are based on the yeast of Roder (1970) and Lee and Komagata (1980).
This agrees well with the properties of Candida boidinii described by. Therefore, this strain (A-1917-3) was identified as Candida boidinii. In addition, this strain (A-1917-3) and Candida boidi-nii
A comparative study of the morphological characteristics, sugar fermentation ability, carbon source assimilation ability, and other physiological properties of the authentic strain (IAM12269 strain) revealed that the properties of this strain (A-1917-3) were similar to those of candidiasis.・It also matched well with those of Boideinii (IAM12269). The medium used in the present invention is not particularly limited as long as it contains methanol as a main carbon source. As a carbon source, in addition to methanol, various carbohydrates, organic acids, etc. may be further added, and as a nitrogen source, organic ammonium salts, inorganic ammonium salts, urea, etc. can be used. Furthermore, various phosphates, sulfates, etc. can be used as inorganic substances, and various organic nutrients can also be added as necessary. Cultivation is usually carried out under aerobic conditions for about 12 hours to 14 days. The pH of the medium is selected from 4-10, and the temperature is selected from about 20-40°C. In the production of propionic acid, both proliferating bacterial cells and dormant bacterial cells can be used. When collecting and purifying propionic acid from a culture, methods generally used for collecting and purifying organic compounds can be employed. (Example) Hereinafter, the present invention will be further explained with reference to Examples. The substances in the Examples were identified by comparing them with standard samples by gas chromatography-mass spectrometry and the like. Example 1 Methanol 40g, NH ₄ Cl4g, K ₂ HPO ₄ 1g,
Na ₂ HPO ₄ 1g, MgSO ₄・7H ₂ O 0.5g, pyridoxine hydrochloride 1mg, biotin 0.01mg, thiamine riboflavin hydrochloride 1mg, sodium D-pantothenate 1
mg, folic acid 0.01 mg, FeSO ₄・7H ₂ O 1 mg, ZnSO ₄・
_7H2O1mg , _CuSO4・_5H2O0.1mg , _MnCl2・
A medium with a pH of 7.0 consisting of 0.04 mg of 4H ₂ O and 1 part of water was prepared. Dispense 50ml of this medium into a 500ml container,
Sterilized at 120°C for 10 minutes. Slant culture of Candida boideinii A-1917-3 isolated from natural soil (30°C, 3 to 6 days) A loopful of the bacteria was inoculated into the above Colben, and 112
Culture was carried out at 30° C. for 10 days using a reciprocating shaker at a reciprocating rate of 10 days, and 1 mg of propionic acid was obtained from 50 ml of this culture (isovaleric acid, 2-methylbutyric acid, and isobutyric acid were obtained as products at the same time).

Claims (1)

[Claims] 1. A method for producing propionic acid, which comprises culturing a microorganism belonging to the genus Candida and having the ability to produce propionic acid using methanol as a carbon source, and obtaining propionic acid from the culture.