JPH0429347B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for culturing vitamin-producing microorganisms, and more particularly, to a method for culturing vitamin-producing microorganisms under irradiation with light in a specific wavelength range to improve the productivity of vitamins. This article relates to a method for culturing productive microorganisms. The present inventor happened to discover how light conditions affect the growth of various useful plants, the control of the growth of pathogenic fungi on useful plants, the cultivation of algal plants, etc. The present inventors have discovered that vitamin productivity can be greatly improved by culturing vitamin-producing microorganisms under active irradiation with a specific light beam substantially containing light of at least 280 nm and above, and have thus completed the present invention. Ivy. Thus, according to the present invention, in the method for producing vitamins by culturing vitamin-producing microorganisms while irradiating them with light, the microorganisms include bacteria, actinomycetes, and fungi that have the ability to produce vitamins. The irradiation time of the light beam is after the logarithmic growth phase of the microorganism in the culture system, and the light beam substantially contains light in a wavelength range of at least 280 nm or more. Provided is a method for culturing vitamin-producing microorganisms, characterized by: The term "vitamins" as used in the present invention refers to vitamins and intermediate compounds thereof. Examples of vitamins include vitamin M (folic acid), vitamin B ₂ (riboflavin), vitamin B 6 (pyridoxine), and vitamin B ₆ (pyridoxine).
_B12 (cyanocobalamin, hydroxocobalamin,
methylcobalamin), vitamin H (biotin), and vitamin B ₁ (thiamine), and intermediate compounds include, for example, ergosterol [intermediate compound of vitamin D (calciferol)], 2-ketogluconic acid [isovitamin C (intermediate compound of D-araboascorbic acid, erythorbic acid)], L
- Sorbose [intermediate compound of vitamin C (ascorbic acid)] etc. As used herein, "vitamin-producing microorganisms"
refers to microorganisms that have the ability to produce vitamins as metabolic products outside the microbial cells, and such microorganisms include fungi, actinomycetes, bacteria, and yeasts. Generally speaking, the method of the present invention can be applied to any type of microorganism, as is clear from the experience of the present inventors and the results of the examples described below. Although the effect of improving the productivity of vitamins can be expected to a greater or lesser extent, the effect is particularly remarkable against microorganisms such as fungi, bacteria, actinomycetes, and yeast, and bacteria and yeast are particularly preferred. Bacteria are particularly preferred. Examples of typical microorganisms to which the method of the present invention can be applied are as follows. In the microorganism examples below, the genus and species are shown in Japanese, followed by the original name in parentheses. 1 Bacteria 1) Corynebacterium genus (1) Corynebacterium simplex (C.
simplex) (2) Corynebacterium primorioxydans (C.primorioxydans) 2) Brevibacterium (Brevibacterium)
Genus (1) Brevibacterium ammoniagenes (Br.ammoniagenes) 3) Arthrobacter (Arthrobacter) Genus (1) Arthrobacter simplex (A.
(2) Arthrobacter globiformis (A.
globiformis) (3) Arthrobacter paciens (A.
pascens) 4) Bacillus genus (1) B. megaterium (2) Bacillus sphaericus (3) B. subtilis 5) Escherichia genus ( 1) Esierichia freundii (E.
freundii) (2) E.coli 6) Pseudomonas genus (1) Pseudomonas mutabilis (Ps.
(2) Ps. denitrificans (3) Ps.
fluorescens) (4) Ps.methanica 7) Acetobacter genus (1) Acetobacter suboxidans (Ace.
suboxydans) 8) Propionibacterium genus (1) Propionibacterium freudenreichii (2) Propionibacterium shermanii (Pr. shermanii) 9) Clostridium ( Clostridium) genus (1) Clostridium butyricum (Cl.
butyricum) (2) Clostridium acetobutyricum (Cl.acetobutyricum) 10) Butyribacterium genus 11) Serratia genus (1) Serratia marcietsiens (Se.
marcescens) 12) Gluconobacter genus (1) Gluconobacter roseus (Gl. roseus) (2) Gluconobacter oxydans (Gl.
oxydans) 13) Klebsiella genus 14) Flavobacterium
Genus 15) Genus Protaminobacter (1) Pro.ruber 16) Genus Rhodopseudomonas (1) Rhodops.spheroides 17 ) Genus Selenomonas (1) Selenomonas ruminanteium (Sele・
ruminantium) 18) Genus Rhodospirillum (1) Rhodospirillum (Rhdodospi.
rubrum 19) Spirillum genus (1) Spirillum (Spi.rubrum) 2 Yeast fungi 1) Candida genus (1) Candida Guillermondii (C.
guilliermondii) (2) C. tropicalis (3) C. arborea (4) C. flaveri (5) C.
2) Genus Crebrothecium (1) Cr.ashbyi 3) Genus Eremothecium (1) Er.ashbyi 4) Genus Ashbaya (1) Cr.ashbyi Gossypii (As.gossypii) 5) Genus Torulopsis (1) Torulopsis candida (T.candida) 6) Saccharomyces
The genera include Corynebacterium, Brevibacterium, Arthrobacter, Bacillus, Gluconobacter, Acetobacter, etc.
The genera Pseudomonas, Serratia, and Propionibacterium are preferred, and the genera Gluconobacter, Acetobacter, Pseudomonas, Brevibacterium, Arthrobacter, and Propionibacterium are particularly preferred. (1) Satucharomyces cerevisiae (S.
cerevisiae) 7) Sporidiobolus
Genus (1) Sporidiobolus salmonicoloa (Sp.
salmonicolor) 8) Pichia genus (1) Pichia guillermondei (Pi.
guilliermondii) 9) Genus Hansenula 10) Genus Rhodotorula (1) Rhodotorula rubra (Rh.rubra) 12) Mycocandida
Genus (1) Mycocyandida riboflavina (My.
riboflavina), among others, the genus Eremothecium, the genus Asibia,
The genera Pichia, Satucharomyces, Klebrothecium and Candeida are preferred, and the genera Eremothecium and Klebrothecium are particularly preferred. 3 Fungi 1) Blaxlea genus (1) Blaxlea trispora (Bl.trispora) 2) Neurospora genus (1) Neurospora cytophylla (Neu.
sitophila) 3) Choanephora genus (1) Choanephora trispora (C.trispora) 4) Penicillium genus (1) Penicillium membranae faciens (2) Penicillium notatum (Pen.notatum) (3) Penicillium lilacinum (4) Penicillium verrucosum (Pen.
verrucosum) (5) Penicillium puberum (Pen.
puberulum) (6) Penicillium. Patulum (Pen.patulum) (7) Penicillium chrysogenum (Pen.
chrysogenum) 5) Aspergillus genus (1) Aspergillus niger (2) Aspergillus fumigatus (Asp.
fumigatus) (3) Aspergillus terreus (4) Aspergillus oryzae (Asp. oryzae) 6) Paecilomyces genus (1) Paecilomyces lilacinus (Pae.
lilacinus) 7) Genus Mucor (1) Mucor azygosporus (Mu.
azygosporus) (2) Mucor microporus (Mu.
microsporus) 8) Cunnighamella genus (1) Cunnighamella brakesliana (Cun.
9) Cladosporium genus (1) Cladosporium herbalum (Clado.
herbarum) (2) Cladosporium reginae (Clado.
resinae) 10) Gibberella genus (1) Gibb.fujikuroi 11) Fusarium genus (1) Fusarium solani (Fu.solani) 12) Acremonium genus (1) Acre Monium Deiospiri (Acrem.
diospyri), among which Braxlea spp., Penicillium spp., and Aspergillus spp. are preferred. 4 Actinomycetes 1) Genus Nocardia (1) Nocardia lutea (2) Nocardia methanophyllus (N.
methanophilus) (3) Nocardia gardnerii (N.
gardonerii) 2) Mycobacterium
Genus (1) Mycobacterium smegmatis (My.
smegmatis) 3) Streptomyces
Genus (1) Streptomyces olivaceus (St.
olivaceus) (2) St. argenteolus 4) Genus Micromonospora (1) Micromonospora chalcea (Streptomyces genus and Nocardia genus) are preferred, and Nocardia genus is particularly preferred. Conventionally, industrial production of vitamins by fermentation has generally been carried out in a dark tank from beginning to end, under conditions that substantially avoid exposure to light. In contrast to such conventional fermentative production methods for vitamins, the present invention involves culturing microorganisms while actively irradiating the light beams containing the above-mentioned specific light beams. The method is essentially different from traditional fermentation methods. Irradiation with the above specific light beam can be applied to both preculture and main culture in the vitamin production process, but the effect will be greater if it is applied during main culture. As long as the irradiable light substantially contains light in the wavelength range of at least 280 nm and above,
There is no particular restriction, and not only artificial light but also natural light can be used as long as the light substantially contains light in the specific wavelength range. Therefore, when using artificial light and/or natural light, use a light filter as necessary,
The amount of light irradiated with light that substantially contains light in the wavelength range of at least 280 nm and above is
It is preferable to culture under artificial light irradiation at a level of 100000 μw/cm ² or more, preferably 300001 μw/cm ² or less, and more preferably 10000 to 1000 μw/cm ² . According to the method of the present invention, the intensity of the light rays irradiated onto the microorganism culture system is not strictly limited, and varies depending on the type of microorganism to be cultured and other culture conditions, and is determined to be optimal in each case. Irradiation conditions can be easily determined by those skilled in the art by conducting small-scale experiments, but in general,
The amount of light in the visible light region with a wavelength in the range of 400 nm to 800 nm is 100,000 μw/cm ² or less, preferably 50,000 ~
1 μw/cm ² , more preferably 10000 to 5 μw/cm ² ,
It is particularly advantageous to irradiate with a light beam adjusted to a range of preferably 5000 to 50 μw/cm ² . Also,
It is preferable that the light in the ultraviolet region with a wavelength of 280 nm to 400 nm is not too strong, and the intensity of the ultraviolet light in this wavelength range is generally 80000 μw/cm ² or less, preferably
40000μw/ ^cm2 or less, more preferably 10000~
It is desirable to set it to 1 μw/cm ² , particularly preferably 5000 to 1 μw/cm ² . Further, according to the method of the present invention, a specific method of actively irradiating the microorganism culture system with the specific light beam includes, for example, in a system (inside a tank) that is substantially sealed from external light; at least
Light that substantially contains light in the wavelength range of 280 nm and above, preferably artificial light that substantially contains light in the wavelength range of 280 to 800 nm (in this case, the artificial light source itself has such light quality characteristics) A method of irradiating an artificial light source (which may emit light, or by covering an artificial light source with a suitable filter so that the emitted light has the light quality characteristics described above); the sun or natural light. Under the irradiation of the light beam, the light beam substantially contains light in the wavelength range of at least 280 nm and above, preferably from 280 to 800 nm.
A method of culturing under the conditions of coating with a transparent colorless to colored organic or inorganic coating material (e.g., a synthetic resin film containing an ultraviolet absorber) that transmits light that substantially contains light in the wavelength range of ; Also, a combination of both of the above methods can be considered. According to the method of the present invention, the time to start irradiating the vitamin-producing microorganisms with the light beam substantially containing light in the specific wavelength range is determined in the microorganism culture system.
A logarithmic growth phase of the microorganism is preferred. The microorganism is
When the cells are inoculated into a culture system, they do not rapidly proliferate immediately, but after passing through the lag phase, they enter the logarithmic growth phase in which they proliferate rapidly. After the logarithmic growth phase, the microorganisms go through a stationary phase as nutrient sources in the system are depleted, and then decrease in number and die. According to the present invention, the irradiation with the light beam substantially containing light in the specific wavelength range starts during the logarithmic growth phase, preferably during the early phase, and more preferably during the middle phase of the logarithmic growth phase. In addition, the period of irradiation with the light beam substantially containing light in the above-mentioned specific wavelength range includes the period from the start of the irradiation until the end of fermentation, or until the time when fermentation reaches a certain stage, etc. Preferably until the end of fermentation. Note that the irradiation format includes a continuous irradiation method in which irradiation is performed continuously, an intermittent irradiation method in which irradiation and darkness are alternately repeated, and a combination method thereof, which can be selected as appropriate. In the present invention, "substantially containing light rays in the wavelength range of X nm and above" means not only that there is no light rays in the wavelength range less than X nm out of the total amount of light irradiated, but also that the ultraviolet rays in the wavelength range of less than X nm are completely absent. This means that there is no problem even if it is contained in a small amount within a range that does not adversely affect the culture of the present invention. Furthermore, in the present invention, "substantially containing light in the wavelength range of Y to Znm" means not only a case where the light in the wavelength range of Y to Znm accounts for 100% of the total light dose to be irradiated, but also 60% of the total amount of light to be irradiated. The ratio is preferably 80% or more, more preferably 90% or more. The cultivation of vitamin-producing microorganisms according to the method of the present invention can be carried out under exactly the same conditions as those conventionally used, except that the culturing is carried out under irradiation with the above-mentioned specific light rays. for example,
This can be carried out by culturing vitamin-producing microorganisms in a suitable nutrient medium in liquid or solid state. Nutrient sources, nitrogen sources, inorganic salts, etc. of the culture medium at this time are appropriately changed and selected depending on the microorganisms and culture means used, but those commonly used for culturing microorganisms are widely used. The carbon source may be any assimilable carbon compound, such as glucose, sucrose, lactose, maltose, starch, dextrin, molasses, glycerin, hydrocarbons, ethyl alcohol, methyl alcohol, acetic acid, and the like. The nitrogen source may be any nitrogen compound that can be used, such as corn stew liquor, soybean flour, soybean protein hydrolyzate, cottonseed oil,
Wheat gluten, peptone, meat extract, yeast extract, yeast, casein hydrolyzate, ammonium salts, nitrates, etc. are used. Examples of inorganic salts include phosphate, magnesium, calcium,
Salts such as potassium, sodium, zinc, iron, and manganese are used as needed, along with various vitamins, amino acids, nucleic acid-related substances, and various precursors for fermentation raw materials. The culture temperature and culture time vary somewhat depending on the microorganism used, and can be changed as appropriate within the range that allows the microorganism to grow sufficiently. For fungi and yeasts, it is preferable to culture at about 20 to 26 degrees Celsius, and for actinomycetes to about 26 to 32 degrees Celsius. In the present invention, the material used for culturing under the above light quality conditions is not particularly limited as long as it has the above light transmission characteristics, and any type of material may be used. It can also be used as a dressing. Such materials can usually consist of inorganic or organic films, plates, or other molded bodies. For example, inorganic films or plates typically include glass plates mixed with dyes or pigments (e.g. emerald green), glass plates coated with or laminated with synthetic resin films containing general ultraviolet absorbers, and Examples include glass filters, and as the organic film or plate, a synthetic resin film or plate coated with or containing an ultraviolet absorber is particularly suitable. In addition to the thermoplastic resins described below, thermosetting resins such as melamine resins, phenolic resins, epoxy resins, silicone resins, urea resins, alkyd resins, and allyl phthalate resins can also be used as resins that can be used for this molding. be able to. The transparent film or plate that can be used in the present invention can be produced, for example, by blending a suitable ultraviolet absorber with a normal film-forming thermoplastic resin and molding the mixture into a film or plate. Examples of usable film-forming thermoplastic synthetic resins include polyvinyl chloride, polyvinylidene chloride, polyethylene, polypropylene, polystyrene, polyester, polyamide, polycarbonate, polymethyl methacrylate, polyacrylate, polyvinyl acetate, polyvinyl alcohol,
Fluorine-containing resin, cellulose resin, ABS resin, etc.
It also includes copolymers or blends containing these polymers as the main component (preferably 50% by weight or more), particularly polyvinyl chloride, polyethylene, polypropylene,
Polyester, fluorine-containing resin, cellulose resin and polycarbonate are suitable. As an artificial light source that can be used for this study, any light source that emits light in the above-mentioned specific wavelength range can be used. Such light sources include, for example, fluorescent lamps, mercury lamps, sunlight lamps, general light bulbs, flood light bulbs, special light bulbs (from the Toshiba Lamp Catalog, Toshiba Electric Materials Co., Ltd.), and the like. More specifically, fluorescent lamps (product names are shown in parentheses). ]
As, daylight (FLF40SW/EM, Toshiba), Plantorx (FL40B/NL, Toshiba), Fuitsyulux (FL40SBRF/NL, Toshiba), blue (FL40B/NL, Toshiba), blue-white (FL40BW/NL,
Toshiba), white (FL40SD/NL, Toshiba), daylight (FL40SD/NL, Toshiba), deluxe (FL40SW
-DL-X/NL, Toshiba), warm white (FL40SW/
NL, FL40SW-/A/NL, Toshiba), for leaf tobacco
6100〓 (FL40SRD-SDL6100〓, Toshiba), for photography (FL40SD-SDL-CP/NL, Toshiba), blacklight fluorescent lamp (FL40SBL-B Matsushita),
Fluorescent lamps for health line (FL20S-E Matsushita), fluorescent chemical lamps (FL20S-BL Matsushita), high color rendering fluorescent lamps (FL20SW-EDL-50K, Toshiba), fluorescent lamps for insect traps (FL20SBA-37K, Toshiba), etc. Of these, black light fluorescent lamps, health line fluorescent lamps, blue and blue-white lamps are preferred. According to the method of the present invention described above, in the production of vitamins by fermentation method, by culturing microorganisms under specific light quality conditions, the production of vitamins is greatly promoted, which is useful in the fields of medicine, food, etc. The contributions made are extremely significant. Next, the present invention will be further explained with reference to Examples. Example 1, Comparative Examples 1 and 9 500ml of an aqueous solution having the composition shown in Table 1
ml Erlenmeyer flask, autoclave sterilized, and inoculated into a YM Agar (Difco0587) slant in advance.
Asibi (Eremothecium asibi)
[Crebrothecium ashbyi (Eremothecium
ashbyii) ATCC26614] was inoculated from a dark yellow colony with high riboflavin production ability, and precultured for 48 hours under dark conditions at a culture temperature of 30°C and a shaking speed of 200 times/min. Prepare a medium in advance by adding 3% soybean oil to the aqueous solution shown in Table 1, and add 100ml of the aqueous solution.
Dispense into a 500ml Sakaguchi flask made of Hario glass,
After sterilization at 110°C for 10 minutes, inoculate 2 ml of the above preculture suspension, culture temperature at 30°C, shaking speed at 200 times/min,
Main culture was performed under dark conditions.

[Table] Growth 24 hours after the start of main culture, it was confirmed by the viable cell count that the bacterial growth had reached the middle of the logarithmic growth phase. Indicated
A shaking culture machine equipped with fluorescent lamps that emit light in the wavelength range of 280 to 360 nm and 300 to 800 nm (culture temperature
Culture flask at 30℃, shaking speed 200 times/min)
Ten plants were transferred and culture continued. The remaining 10 culture flasks continued to be cultured in the dark. The culture time was 144 hours from the start of culture, and continuous irradiation culture was performed in the light irradiation section. Further, from the beginning of the main culture, culture was performed under the same light irradiation conditions as in Example 1 (Comparative Example 9). The culture results are shown in Table 3. The culture results (amount produced) are as follows:
This is the average value of the values obtained from the culture flasks (10 flasks) in each group.

【table】

[Table] Example 2, Comparative Example 2 Pre-medium consisting of sorbitol 5%, yeast extract 0.5%, peptone 0.3%, CaCO ₃ 0.2% (separately sterilized), and sorbitol 20%, yeast extract 0.5%
%, CaCO ₃ 0.2% (separately sterilized), the sorbose-producing (produced from sorbitol) microorganism Gluconobacter oxydanssubsp.
suboxydans (Acetobacter suboxydans) ATCC
621] was cultured in the same manner as in Example 1 and Comparative Example 1. However, the main culture was for 120 hours, and in the light irradiation group, light irradiation culture was started from the 7th hour of culture.
The culture results are shown in Table 4.

[Table] *Yield based on sorbitol Example 3, Comparative Example 3 Vitamin _B12- producing microorganism Propionibacterium siamanii cultured in tomato juice Agar slant
shermanii IFO 12391) were collected in sterile physiological saline, and evenly inoculated into 20 500 ml Erlenmeyer flasks (sterilized) containing 100 ml of a culture solution with the composition shown in Table 5 prepared in advance. It was statically cultured under dark conditions at 30°C. During static culture, the pH of the culture solution was adjusted to around neutrality once a day. On the 4th day of culture, aluminum sulfate (sedimentant) was added at a concentration of 10 mg/ml, and the cells were allowed to settle for 2 hours.
Remove 40ml of supernatant and use new medium (same composition)
I replaced it with 40ml. At this time, 5,6-dimethylbenzimidazole was added at a concentration of 10 mg, and the culture was continued for another 2 days. In addition, static culture started at 18
Example 1: 10 out of 20 culture flasks at hour
The plants were transferred to the same light irradiation conditions as shown in , and the remaining 10 plants continued to be cultured in the dark, and both groups were cultured in exactly the same way except for the difference in light conditions. The culture results (average values obtained from 10 culture flasks) are shown in Table 6.

【table】

【table】

[Table] Example 4, Comparative Example 4 500ml containing 100ml of aqueous solution with the composition shown in Table-7
After sterilizing and cooling the Sakaguchi flask, collect the vitamin _B12 -producing microorganism Propionibacterium fredenrechii.
One platinum loop of ATCC 6207) was inoculated and precultured for 48 hours at 30° C. in the dark at a shaking speed of 200 times/min.
This medium 1 having the composition shown in Table 8 was dispensed in advance into two Erlenmeyer flasks, and after sterilization and cooling, 50 ml of the above pre-cultured cell suspension was inoculated therein. The main culture was a static culture for 96 hours under dark conditions at 30°C, and in the light irradiation section, light irradiation culture was performed in the same manner as in Example 3. The culture results are shown in Table-9.

【table】

【table】

[Table] Examples 5 and 6, Comparative Examples 5 and 6 Biotin productivity (cis-tetrahydro-2-oxo-4-n-pentyl-thieno- [3,4-d]
- Produced from imidazoline) microorganism Arthrobacter paraffineus
ATCC 21003) and Brevibacterium ketoglutamicum
ATCC 21004) were cultured separately in the same manner as in Example 1 and Comparative Example 1. However, the preculture is 24
The main culture time was 120 hours, and after the start of the main culture, cis-tetrahydro-2-oxo-4-n-pentyl-
2 ml of an ethanolic solution of thieno-[3,4-d]-imidazoline (50 mg/ml) was added to each flask. In addition, in the light irradiation section, light irradiation culture was started after 7 hours of culture. The culture results are shown in Table 11.

【table】

[Table] Example 7, Comparative Example 7 Biotin productivity (cis-tetrahydro-
2-oxo-4-n-pentyl-thieno-[3,
4-d]-produced from imidazoline) microorganism Pseudomonas mutabilis
mutabilis ATCC 31014) was cultured in the same manner as in Example 6 and Comparative Example 6, except that the culture temperature was 25°C.

【table】

【table】 The culture results are shown in Table-14.

[Table] Example 8, Comparative Example 8 An aqueous solution consisting of 4 g of yeast extract, 10 g of malt extract, 4 g of glucose, and 1 part of distilled water was prepared to a pH of 7.3, and 100 ml of this aqueous solution was dispensed into a 500 ml Erlenmeyer flask and sterilized by autoclaving. After, vitamin B _6- producing microorganism Nocardia SP (Nocardia gardneri)
[Nocardia sp (Nocardia gardneri ATCC)
21519] was inoculated with one platinum loop, 28℃, shaking speed.
Preculture was performed at 200 times/min for 48 hours in the dark.
Prepare an aqueous solution according to Table 15 in advance, and pour the 3.5 aqueous solution into two 7.5 Pyrex

[Table] After dispensing each into a glass jar fermenter and sterilizing it, inoculate it with 350 ml of the above pre-cultured bacterial cell suspension, culture temperature 28℃, stirring speed 550 rpm, aeration rate 3.5 /
Dark culture was started under conditions of 1 minute. After 48 hours, it was confirmed that the growth of bacteria in the tank was in the middle of the logarithmic growth phase by the number of viable bacteria and the amount of carbon dioxide gas exhausted. Light irradiation was started on one jar fermenter, and the other Jiyahua Mentor continued his dark cultivation.
A table is given to the person who started the light irradiation.
16, shown in Figure-1 and Figure-2. Fluorescent lamps emitting light in the wavelength ranges of 280-360 nm and 300-800 nm are installed surrounding the jar fermentor. The culture time was 144 hours, during which time the pH in the medium was maintained at PH6.8 by feeding with aqueous ammonia.
Continuous irradiation culture was performed during light irradiation, and the results are shown in Table 17.

【table】

【table】 [Brief explanation of drawings]

FIGS. 1 and 2 are specific energy curves by wavelength of irradiation light used in Examples and Comparative Examples.

Claims (1)

[Scope of Claims] 1. A method for producing vitamins by culturing vitamin-producing microorganisms while irradiating them with light, wherein the microorganisms are selected from bacteria, actinomycetes, and fungi that have the ability to produce vitamins. the selected microorganism, the irradiation start time of the light beam is after the logarithmic growth phase of the microorganism in the culture system, and the light beam substantially contains light in a wavelength range of at least 280 nm or more. A method for culturing vitamin-producing microorganisms using light rays. 2. The method according to claim 1, wherein the culturing is carried out under irradiation with light that substantially contains light in the wavelength range of at least 280 to 800 nm. 3. The method according to any one of claims 1 to 2, wherein the irradiation intensity of the light beam is in the range of 100000 to 1 μW/cm ² . 4. The method according to any one of claims 1 to 3, wherein the light beam is an artificial light beam and/or a natural light beam. 5 The vitamins include vitamin _B2 , vitamin
5. The method according to any one of claims 1 to 4, which is _B12 , sorbone, biotin, and vitamin _B6 . 6. The microorganism belongs to the genus Pseudomonas, the genus Propionibacterium, the genus Gluconobacter, the genus Acetobacter, the genus Arthrobacter, the genus Brevibacterium. , the genus Crebrothecium, and the genus Nocardia.