JPS6192591A - Production of xanthan gum - Google Patents

Abstract

PURPOSE:To obtain light-colored xanthan gum, by cultivating a bacterium belonging to the genus Xanthomonas in a medium containing a specific compound. CONSTITUTION:A bacterium (e.g., Xanthomonas campestris IFO13551) is inoculated into a medium at 7-7.2pH obtained by adding 0.0001-0.1wt% one or more compounds selected from pantothenic acid, thiamine and/or their salts to a medium containing 1-5wt% carbon source, 0.1-1wt% nitrogen source, 0.01-5wt% phosphate, 0.01-1wt% Mg salt, and 0.001-0.01wt% very small amount component, it is cultivated at 25-30 deg.C for 75-100hr aerobically, sterilized at about 121 deg.C at about 1atm. for 10-15min, and ethanol or isopropyl alcohol and KCl are added to the culture mixture, to precipitate xanthan gum.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Industrial Application Field The present invention relates to a method for producing light-colored xanthan gum using a medium with a specific composition.

(2) Conventional technology Generally, water-soluble viscous pot $J! Guar gums such as gum arabic, xanthan gum, guar gum, and gum tragacanth are widely used in various industries such as food, paint, paper, and petroleum, and the demand for them has been increasing in recent years. Among them, xanthan gum obtained by microbial fermentation is industrially used as a useful additive due to its excellent thickening effect, emulsion stabilization effect, particle and air spore dispersion effect, and stability in temperature, salt, and pH resistance. The range of applications is expanding.

Xanthan gum has traditionally been produced using microorganisms of the genus Xanthomonas, such as Xanthomonas campestris (Xanthomonas campestris).
nas can+pestris), Xanthomonas carotae (Xanthomonas carotae)
ae ), Xanthomonas phaseoli (Xanth
omonas phaseoli), etc., aerobically cultivated in a medium containing carbon sources such as glucose, sucrose, molasses, and starch, as well as peptone, nitrogen, magnesium, and other trace components. It is manufactured by sterilizing, precipitating with alcohols such as ethanol and isopropyl alcohol, or ferric chloride, and drying. A specific example of a microorganism used in the production of xanthan gum is Xanthomonas campe.
stris's NRRL B-1459 (Japanese Unexamined Patent Publication No. 1983-
165798) or ATCC13951 (Japanese Unexamined Patent Publication No. 5
8-146290) and the like are known.

(3) Problems to be solved by the invention However, using conventional Xanthomonas microorganisms,
Xanthan gum obtained by fermentation with conventional culture medium components has a high degree of coloration after culturing, so when producing it industrially, it must be subjected to appropriate decolorization treatment, and the process is also quite radical. This not only complicates the manufacturing process but also poses a major economic problem.

The object of the present invention is to provide a method for producing xanthan gum that does not have the above-mentioned disadvantages.

(4) Means for solving the problems - As a result of intensive research to achieve this objective, the present inventors discovered that the conventional drawbacks can be solved by using a specific culture medium.

The present invention was completed based on the above findings, and involves the cultivation of a microorganism having xanthan gum production ability belonging to the genus Xanthomonas, in which pantothenic acid is added to a medium containing a carbon source.
This is a method for producing light-colored xanthan gum, which is characterized by adding one or more compounds selected from thiamine and/or their salts, esters, or derivatives.

Microorganisms that can be used in the present invention include Xanthomonas
Campestris (Xanthomonas campe)
stris), Xanthomonas carotae (Xan
thomonascarotae), Xanthomonas
Phaseori (Xanth.

monas phaseoli), Xanthomonas
Xanthomonas begoniae
), Xanthomonas incanae (Xanthomo
nas 1ncanae), etc. Among these, Xanthomonas campestris NRRLB-1459, ATCC13951, and IFO13551 are preferred.

Note that IFO13551 has not been previously known as a xanthan gum growing bacterium, and is the first to be discovered by the present inventors.

In the present invention, conventional carbon sources, nitrogen sources, phosphates and magnesium salts, and trace components can be used as the medium composition necessary for fermenting the above-mentioned microorganisms.

As the carbon source, one or more of sugars such as glucose, sucrose, xylose, molasses, starch, maltose, and dextrin and/or polyhydric alcohols such as glycerin, mannitol, and sorbitol can be used, and the amount used is 1 to 5%, preferably 2 to 5%.
It is 4%.

Nitrogen sources include ammonium nitrate, sodium nitrate, urea, monosodium glutamate, alanine, etc. 0.1-1%
Can be used in combination.

As phosphates, monopotassium phosphate, dipotassium phosphate, monosodium phosphate, disodium phosphate, etc. can be used.
The amount used is 0.01-5%, preferably 0.1-1%
It is.

The magnesium salt is selected from magnesium phosphate, magnesium nitrate, magnesium sulfate, etc., and the amount used is 0.01 to 1%, preferably 0.01 to 0.5%.

Trace components include ferrous chloride, ferric chloride, ferrous nitrate, ferric nitrate, ferrous phosphate, ferric phosphate, zinc sulfate, zinc chloride, zinc nitrate, and zinc phosphate. One or more types can be selected from the following, and the amount used is from 0.001 to
0.01% is suitable, preferably 0.001-0.0
05%.

One or more of the components characterized by the present invention, namely pantothenic acid, thiamine and/or their salts, esters, or derivatives, are added to the medium at 0.0001-0.1%.
%, preferably 0.001 to 0.05%. If it is less than 0.0001%, it will have an effect on the viscosity, xanthan gum concentration, and color of the fermentation liquid (see Table 2).
Moreover, if it exceeds 0.1%, the chromaticity of the fermented liquid will not be significantly improved and the viscosity will tend to decrease slightly. As the pantothenic acids, pantothenic acid, sodium pantothenate, potassium pantothenate, calcium pantothenate, methyl pantothenate, ethyl pantothenate, butyl pantothenate, pantothenic amide, etc. can be used.

Thiamines can be selected from thiamine, thiamine hydrochloride, thiamine monophosphate, thiamine diphosphate, thiamine disulfide, and the like.

A medium having such a composition was adjusted to pH 7 to 7.2, inoculated with the above-mentioned microorganisms, and stirred with aeration at 25 to 30°C.
Culture for 5-100 hours. After completion of the culture, the mixture is sterilized at 121° C. and 1 atm for 10 to 15 minutes, ethanol or isopropyl alcohol and potassium chloride are added to precipitate xanthan gum, which is then dried and crushed to obtain a powder.

Note that the above culture conditions are merely examples, and the present invention is not limited thereto.

The fact that the product obtained from the culture in this way is xanthan gum is that its chemical composition is glucose: mannose: glucuronic acid = 2:2:1 as a result of acid hydrolysis, and that the infrared absorption spectrum of xanthan gum is This is confirmed by the fact that the viscosity of the constant concentration aqueous solution shows the same behavior as the xanthan gum aqueous solution (Table 1).

Table-1 * Fermentation product obtained in Example 1 *'*Xanthomonas campestris
Using the culture medium of the present invention, the fermentation product of NRRL B-1459 under the same conditions as Xanthomonas cam
As shown in Table 2, the chromaticity of the fermentation stock solution obtained by culturing and sterilizing S. pestris IOF13551 was extremely pale compared to the case of culturing in the above-mentioned conventional medium.

Table 2 Notes (1) Viscosity: Measured using Fermentation 2 (1200 ml) using a B-type rotational viscometer, rotor No. 3, 12rprrI.

(2) Xanthan gum concentration: saturated KCI in 40g of fermentation liquid
10 drops of an aqueous solution were added, precipitated with 80 ml of 95% ethanol, washed twice with the same ethanol, and air-dried to obtain xanthan gum. Ki x 100 (3) Chromaticity Measured with a Nigardner chromaticity meter.

(4) Conventional medium composition (5) Medium composition of the present invention Although JP-A-58-165798 discloses the addition of fumaric acid, malic acid, etc. as specific components of the fermentation medium, Table 2 shows that As is clear, malic acid (0,
2%), the coloring of the fermented liquid becomes significant. Fumaric acid (
Similarly, when 0.2%) was added, the coloring was also significant.

Example 1 Glucose: 2.5%, yeast extract 20.2%, Kz
HP Os: 0, 5%, MgS Oa
・7H20: 0.1%, FeC1z' 7Hz
Q: 50 ml of a medium containing 1% o, oo was placed in an Erlenmeyer flask with a cotton stopper, and the pH was adjusted to 7.0.
Sterilize for 15 minutes at 1°C and 1 atm.
nas campestris I F 013551
Add 0.5 ml of the same medium suspension and incubate at 28°C, 250r,
p, a Cultured for 96 hours under rotary shaking conditions. After completion of fermentation, the mixture was sterilized under the same conditions, diluted 4 times with distilled water, and the bacterial cells were removed by centrifugation. To this, 15 mL of a saturated aqueous KCI solution and 350 ml of 95% ethanol were added to form a precipitate, which was further washed twice with the same amount of ethanol and three times with 200 ml of acetone, and then the crystals were air-dried.
Fibrous white crystals were obtained.

Viscosity of fermented liquid after fermentation: 9900cps/25℃
, crystalline concentration: 1.8%, and chromaticity (Gardner): 261. In addition, the properties of the purified fibrous white crystals are as follows: browning temperature: 160°C, sugar composition by acid hydrolysis: nigercose/mannose/glucuronic acid = 2:2:1, and infrared absorption spectrum (Figure 1) of xanthan gum. That (Figure 2)
matched. Viscosity of 0.5% aqueous solution of crystals: 380c
ps/25°C, 1. Viscosity of 0% aqueous solution: 980cp
s/25°C.

Example 2 G) Lt': I-S: 3.5%, NH4NO3: 0.
06%, KJPO4: 0.5%, MgSO4' 7
HzO: 0, 1%, FeCh 71120:
o, 001%, Zn5O,'7 HzO: 0°001% and sodium pantothenate: 0.001,
% Thiamine: 2゜L medium containing 1% O, OO and Xant
homonas campestris IFO135
The same medium suspension 11 of No. 51 was placed in a jar fermenter No. 501 at 27° C., aerated at 0.5 V, Air/V, medium/min, and stirred at 500 r, p, m.
After culturing for a period of time and completing fermentation, the same treatment as in Example 1 was carried out.

The viscosity of the fermented liquid after sterilization was: 9,800 cps/25°C, the Pi concentration: 1.8%, and the chromaticity (Gardner): 61.

The properties of the purified product were the same as those obtained in Example 1.

Example 3 Sucrose: 2.2%, Alanine: 0.6%, Na
zHPOs: 0. 5%, MgSO4・7HzO
: 0, 3%, Fe(NO:+)z: 0,
003%, ZnC1z: 0.001% and methyl pantothenate: 0.03%, thiamine hydrochloride: 0.0
Medium containing 01% and Xan Lhomonas cam
Fermentation was carried out in the same manner as in Example 2 using Pestris NRRL B-1459 to obtain white crystals.

Viscosity of fermented liquid at the end of fermentation: 10500cps/25
°C, polysaccharide concentration = 1.9%, chromaticity (Gardner): 02
Met. Further, the properties of the purified product were the same as those obtained in Example 1.

Example 4 77Lz dose: 3.0%, urea: 0.5%, KH2P
O4: 0.2%, Mg(N(h)z: 0, 1%
, FeC1z''78zO: 0.003%, and pantothenic acid: 0.005%, thiamine monophosphate: 0.
Medium containing 02% and Xanthomonap camp
Fermentation was carried out in the same manner as in Example 1 using S. estris ATCC13951 to obtain white crystals.

Viscosity of fermentation liquid at the end of fermentation: 9700cps/25℃
, polysaccharide concentration: 1.8%, and chromaticity (Gardner): 261. Further, the properties of the purified product were the same as those obtained in Example 1.

(5) Effects of the Invention The xanthan gum obtained by the method of the present invention is extremely light in color, and the decoloring treatment in the manufacturing process can be omitted altogether or can be kept to a very light level, which is extremely meaningful in terms of manufacturing. .

[Brief explanation of the drawing]

Figure 1 shows the infrared absorption spectrum of the fermented product obtained in Example 1, and Figure 2 shows the infrared absorption spectrum of xanthan gum. Patent Applicant Nisshin Oil Co., Ltd. Procedural Amendment V (Voluntary) January 7, 1972 Director General of the Patent Office Manabu Shiga 1, Indication of Case Patent Application No. 212451 of 1982 2. Name of the invention Method for producing xanthan gum 3. Relationship with the case of the person making the amendment Patent applicant address ■221 1 Chiwaka-cho, Kanagawa-ku, Yokohama, Kanagawa Prefecture
Name Nisshin Oil Co., Ltd. Research call outage
045 (461) 01814, Detailed Description of the Invention in the Specification Subject to Amendment 5, Contents of Amendment (11 Specification, page 2, line 11, "Xanthomonas" is corrected to "Xanthomonas". (2) Same No. 6 Correct line 13, “Exceed, even” to “Exceed.” (3) Same page, page 8, line 10 r I OF13551 J
is corrected to r IF 013551 J. Procedural amendment (voluntary) 41. Display of the case 1982 Patent Application No. 212451 2, Name of the invention Method for producing xanthan gum 3, Person making the amendment Relationship to the case Patent applicant Postal code 221 Address 1-1, Chiwaka-cho, Kanayō-ku, Yokohama-shi, Kanagawa Prefecture 3 people
Name Nisshin Oil Co., Ltd. Research call outage Call 0
45 (461)0181, Contents of the amendment in the Detailed Description of the Invention column of the specification to be amended +1) Insert “and pantothenic acid: O,001%” after “%” on page 11, line 4 of the specification . (2) On page 12, line 10, ``roi,%'' is corrected to ``01%.''

Claims (2)

[Claims] (1) In culturing a microorganism capable of producing xanthan gum belonging to the genus Xanthomonas, one or more selected from pantothenic acid, thiamine, and/or their salts, esters, or derivatives are added to a medium containing a carbon source. A method for producing light-colored xanthan gum, characterized by adding a compound. (2) A microorganism that belongs to the genus Xanthomonas and has the ability to produce xanthan gum is Xanthomonas campestris (
Xanthomonas campestris)IF
The manufacturing method according to claim 1, which is O13551.