JPH08332081A - Yeast containing magnesium at high concentration - Google Patents

Abstract

PURPOSE: To obtain the subject yeast, containing a specific amount or more of magnesium without any bitterness and astringency and useful for foods, feeds, etc., by culturing a yeast in the presence of a phosphorus compound containing a specific amount or more of phosphorus based on the amount of saccharides used. CONSTITUTION: This yeast contains magnesium at a high concentration. The yeast is obtained by adding magnesium sulfate to a culture medium containing usual nutrient sources required for culturing a yeast such as saccharide and nitrogen sources, vitamins and minor elements, etc., so as to contain >=50ppm magnesium and inoculating the yeast such as a baker's yeast thereinto in the presence of a phosphorus compound containing >=4% phosphorus based on the amount of saccharides used such as sodium ammonium hydrogenphosphate, potassium dihydrogenphosphate, dipotassium hydrogenphosphate, sodium dihydrogenphosphate, disodium hydrogenphosphate or ammonium phosphate. The spinner culture with aeration is then carried out at 3 deg.C for 120hr to thereby afford the objective yeast, containing >=2000ppm magnesium based on the dry fungal cell, having slight bitterness and astringency and useful for production, etc., of foods and drinks, feeds, baits, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an edible yeast containing a high concentration of minerals, especially magnesium, and a method for producing the same.

[0002]

It is well known that magnesium is one of the important trace minerals in the living body. However, in recent years, it has been said that the intake of magnesium has been drastically reduced due to westernization and instantization of eating habits. In addition, the stress often seen in modern people is also a factor that reduces the concentration of magnesium in the body,
There is widespread demand for improved magnesium intake.

[0003] When ingesting magnesium, ingesting a necessary amount of magnesium from ordinary foods and drinks involves considerable difficulty because the magnesium content in foods and drinks is low. Also, although magnesium-fortified foods containing magnesium salts, which are inorganic compounds, are commercially available,
Since it is an inorganic salt, it has a strong bitterness and astringency, and it is extremely difficult to ingest it daily compared to a food containing magnesium, which is a natural ingredient.

[0004]

The present invention has been made to develop a new system for reasonably ingesting a large amount of magnesium orally.

[0005]

Means for Solving the Problems The present invention has been made to achieve the above-mentioned object, and uses a food material having a relatively high magnesium content as in the prior art,
Regarding a system that directly utilizes foods containing inorganic magnesium compounds, the idea was fundamentally changed, and a large amount of magnesium was ingested and accumulated in the edible microorganisms. Focused on the system of ingesting magnesium.

[0006] Then, yeast was cultivated in a magnesium salt-containing medium by paying attention to yeasts widely used for various edible uses, but when the amount of magnesium salt added was increased,
As in the conventional technical common sense, it was not possible to obtain a live yeast containing magnesium at a high concentration due to the inhibition of yeast growth.

However, the inventors of the present invention dared to challenge such common general knowledge and set a new problem of creating a new yeast containing a high concentration of magnesium, which has been impossible in the past. Therefore, as a result of examination from various directions, when yeast was aerobically stirred and / or shaken in a suspension state in a magnesium high concentration liquid, instead of culturing the yeast in a nutrient medium, it was completely unexpected. In addition, a new finding was obtained that a large amount of magnesium was incorporated into yeast cells. Moreover, when yeast was cultured in a liquid containing a high concentration of magnesium and in the presence of a large amount of phosphorus, a new finding was obtained that, unexpectedly, a large amount of magnesium was incorporated into the yeast cells. Moreover, in any case,
Contrary to conventional wisdom, yeast does not die even if the magnesium concentration is increased, and the magnesium content in the yeast cells also increases in accordance with the magnesium concentration in the solution. It was confirmed that the amount reached 000 ppm or more, and the latter reached 2,000 ppm or more. Such yeast containing magnesium in a high concentration has been considered to be impossible to create at all.

The present invention has been completed as a result of further research based on such useful new knowledge, and the details thereof are as described below.

In order to carry out the present invention, it is necessary to suspend the yeast in a high-concentration magnesium-containing solution containing a large amount of a water-soluble salt of magnesium, and agitate and / or shake it normally. . In the present invention, the magnesium concentration in the yeast cells finally created depends on the magnesium concentration in the solution in which the yeast is suspended, regardless of the composition of the medium for culturing the yeast. In other words, it is possible to allow magnesium to be incorporated into yeast even under the condition that a substance necessary for the growth of bacterial cells exists or under the condition that it does not substantially exist.

The magnesium salt used in the present invention may be organic or inorganic, as long as it has appropriate water solubility, does not kill yeast, and is efficiently taken up by yeast cells. All magnesium compounds can be used alone or in combination. Non-limiting examples of which include: magnesium sulfate, magnesium chloride, magnesium citrate, magnesium acetate, primary magnesium tartrate, primary magnesium lactate.

The amount of magnesium salt added is set so that the magnesium concentration in the liquid is 5,000 ppm or more, and is preferably 10,000 to 20,000 ppm. If yeast are treated with such a high concentration of magnesium, the yeast may be killed, or even if it is not killed, serious adverse effects such as reduced activity may be suspected. The invention is significantly transcendental, and, quite unexpectedly, the yeast is not killed by such a high concentration of magnesium, and it is possible to accumulate an extremely high concentration of magnesium in the microbial cells. We obtained a useful new finding that the physiological activity hardly decreases.

As a result, 5,000 pp per dry cell
Finally, we succeeded in incorporating more than m of magnesium into the yeast cells. Such a yeast containing a large amount of magnesium has not existed in the past, and is a novel useful yeast that could not be created even when trying to create it as described above. Even more surprisingly, according to the invention, 20,0
By using a solution containing 00 ppm of magnesium ions, it is even possible to incorporate a very large amount of magnesium of 20,000 ppm or more per dry cell into the yeast cells.

According to the present invention, a large amount of magnesium can be contained in yeast cells by suspending 5 to 30%, preferably 10 to 20% of yeast as wet cells in a magnesium solution, and then 15 to 40 ° C. , Preferably 25-35
C., more preferably 28 to 33.degree. C., treatment time 1 to 120 hours, preferably 36 to 96 hours, pH 4 to 4.
7, preferably pH 4.5-6.0, aeration 0-5vv
m, preferably 1 to 3 vvm, stirring varies depending on the scale of equipment used, but 50 to 1,000 rpm, and 100 to 200 rp for equipment having an amplitude of 12 cm when shaking.
m, preferably 100 to 150 rpm, but can be appropriately selected depending on the type of yeast and magnesium salt used and the concentration thereof, and may deviate from the above range depending on the necessity.

In order to carry out the present invention using phosphorus, it is necessary to culture yeast in a magnesium-containing medium in the presence of high concentration of phosphorus. The culture may be carried out according to a conventional method of yeast culture, and various methods such as aeration and stirring culture and fed-batch culture are appropriately used. As magnesium and phosphorus, water-soluble salts can be used as appropriate.

The amount of magnesium salt added is higher than 50 ppm, preferably 100 ppm or more. If yeast is treated with such a high concentration of magnesium, the yeast may be killed as described above, or serious adverse effects may be suspected even before the yeast is not killed. The invention is vastly transcendental, and, quite unexpectedly, on the contrary, rather than killing yeast with such high concentrations of magnesium,
Coupled with the presence of a high concentration of phosphorus in the medium,
We obtained a useful new finding that extremely high concentration of magnesium can be accumulated in cells.

As a result, 2,000 pp per dry cell
Finally, we succeeded in incorporating more than m of magnesium into the yeast cells. Such a yeast containing a large amount of magnesium has not existed in the past, and is a novel useful yeast that could not be created even when trying to create it as described above.

In order to make the yeast cells to contain a large amount of magnesium according to the present invention utilizing phosphorus, it is necessary to allow a large amount of phosphorus to be present together with magnesium in the medium. The amount of phosphorus is 5 times or more, preferably 10 times or more, and more preferably 20 to 50 times the amount of phosphorus per sugar source used, as compared with the usual baker's yeast production conditions. Specifically, it is preferable to add to the medium a phosphate compound containing phosphorus at 4% or more of the amount of sugar used for culture.

The phosphoric acid compound used in the present invention is
As long as it has appropriate water solubility and does not kill the yeast, and can be efficiently incorporated into the yeast cells,
One or more kinds of all phosphoric acid compounds can be used regardless of whether they are organic or inorganic. Non-limiting examples include: Sodium ammonium hydrogen phosphate (N
aNH ₄ HPO ₄ ), potassium dihydrogen phosphate (KH ₂ P
O ₄ ), dipotassium hydrogen phosphate (K ₂ HPO ₄ ), sodium dihydrogen phosphate (NaH ₂ PO ₄ ), disodium hydrogen phosphate (Na ₂ HPO ₄ ), ammonium phosphate ((NH
₄ ) ₃ PO ₄ ).

In order to make the yeast contain a large amount of magnesium according to the present invention, magnesium and phosphorus are added in addition to the usual nutrient sources such as sugar source, nitrogen source, vitamins and trace elements necessary for culturing yeast. Yeast is cultivated in the contained medium. The addition amount of magnesium depends on the final yeast amount, but is 50 ppm or more, preferably 5
0 to 1,000 ppm, more preferably 100 to 500 p
pm is good. Further, phosphorus is preferably present in an amount of 1 to 40%, preferably 5 to 20% with respect to the sugar source used. The potassium salt is generally a more effective source of phosphorus than the sodium salt.

The culture may be carried out according to a conventional method for culturing yeast, except that phosphorus is essential, and aeration stirring culture, fed-batch culture and the like are appropriately selected and used. The culture is
Yeast is suspended in the above-mentioned medium, and the temperature is 15 to 40 ° C., preferably 25 to 35 ° C., more preferably 28 to 33 ° C.,
Although it is good to carry out at pH 4 to 7, preferably pH 4.0 to 6.0, the culture conditions can be appropriately selected depending on the types and the amounts of yeast, magnesium salt, and phosphorus compound used, and if necessary, these It may deviate from the range.

In the present invention, any yeast, including edible yeast, can be used with or without phosphorus. Non-limiting examples include yeasts belonging to the following genera: Saccharomyces, Torulopsis.
genus sis), genus Mycotorula, genus Torulaspora, genus Candida, genus Rhodotorula, genus Pichia and others.

Specifically, Saccharomyces cerevisiae,
Uvarum, rouxii IFO 0439; Torulopsis utilis, same
candida IFO 0856; Mycotorula japonica, same lipolytic
a; Torulaspora delbrueckii, fermentati; Candida
sake, tropicalis, utilis ATCC 16321; Hansenula
anomala IFO 0140, suaveolens; Saccharomycopsis
fibligera IFO 1665, same lipolytica ATCC 20182; Rhodo
torula rubra IFO 0870; Pichia farinosa IFO 0607,
Other yeasts are exemplified.

Among these yeasts, particularly as edible yeasts, yeasts often used for human food and drink, animal feed, and fish feed include Saccharomyces cerevisiae and uvaru.
Examples include baker's yeast, brewer's yeast, wine yeast, sake yeast, alcohol yeast, amazake yeast, miso soy sauce yeast, feed yeast, and feed yeast, which belong to m, rouxii, Saccharomycopsis fibligera and others.

The yeast thus loaded with magnesium is collected by centrifugation, filtration, etc., and then washed to obtain the desired bacterial cells, and if necessary, freeze-dried or dried cells according to a conventional method. , Used for various purposes. Further, if desired, it is also possible to crush the cells or lyse the cell membrane to take out the contents and use this.

Further, by using the above-described high magnesium-containing yeast production conditions according to the present invention, the obtained high-magnesium yeast is used as a raw material yeast, and further various minerals are added at a high concentration to obtain a novel multi-mineral high yeast. Can be created.

Examples of yeasts with a high content of multi-minerals include yeasts with a high content of magnesium / iron, yeasts with a high content of magnesium / zinc, yeasts with a high content of magnesium / zinc / iron, and the like.

The high-magnesium-iron-rich yeast is obtained by preliminarily producing the high-magnesium yeast as a raw material yeast under the above-described high-magnesium yeast production conditions according to the present invention. It can be manufactured by a method of incorporating into.

The iron-rich yeast production conditions are as follows:
This is a method of suspending yeast in a solution containing 000 ppm or more and slowly stirring and / or shaking in a non-proliferative manner to the extent that yeast does not settle.

In order to carry out the present method, yeast is suspended in a high-concentration iron-containing solution containing a large amount of a water-soluble salt of iron, and the mixture is stirred and /
Or it is necessary to shake. In this method,
It does not use a medium for culturing yeast, but treats it non-proliferatively. In other words, yeast is treated under conditions in which substances necessary for the growth of bacterial cells are substantially absent.

The iron salt used in the present method may be any one as long as it has appropriate water solubility, does not kill yeast, and is efficiently incorporated into yeast cells.
One or more of all iron compounds, organic or inorganic, can be used. Non-limiting examples of which include: ferrous sulfate, ferrous chloride, ferrous citrate,
Ferrous fumarate, ferrous gluconate, ferrous butyrate, ferrous tartrate, ferrous lactate.

The amount of the iron salt added is higher than 1,500 ppm, preferably 2,000 ppm or more. If yeast is treated with iron at a concentration as high as 2,000 ppm, the yeast may be killed, or even if it is not killed, serious adverse effects may be suspected. Unexpectedly, rather than letting yeast die even at such a high concentration of iron, it can be taken up in large quantities in the cells. Moreover, 10,000 ppm
It has also been confirmed that it is possible to treat with a high concentration of iron.

As a result, 15,000 p per dry cell
For the first time, it became possible to incorporate iron of pm or more into yeast cells. Even more surprisingly, according to the present invention, it is even possible to incorporate a very large amount of iron of 30,000 ppm or more into yeast cells by using an iron solution of 10,000 ppm.

The treatment conditions for incorporating iron into the yeast cells are as follows.
C., preferably 20 to 35.degree. C., 0.5 to 72 hours, preferably 1 to 36 hours, pH 4 to 7, preferably pH 4.5 to 6.5, but the type of yeast and iron salt used. Or appropriately determined according to its concentration, and may be outside the above range in some cases.

Stirring and / or shaking must be carried out at a slow speed such that the yeast and iron ions come into contact with each other,
500 rpm, depending on the viscosity of the iron solution and the yeast content
Below, preferably a gentle agitation of 200 rpm or less,
Or, when the amplitude is 12 cm, it is preferable to shake at 200 rpm or less, preferably about 150 rpm or less.

As described above, the magnesium-iron-rich yeast can be produced. As a result, a novel multimineral edible yeast containing 2,000 to 5,000 ppm of magnesium and 15,000 ppm or more of iron per dry cell can be obtained.

To produce a high-magnesium / zinc-containing yeast, the high-magnesium-containing yeast previously produced under the above-described high-magnesium-containing yeast production conditions according to the present invention is used as a starting yeast, It can be produced by a method of incorporating zinc into yeast.

Yeasts high in zinc are produced under the conditions for producing yeasts high in zinc, that is, in a solution containing 50 ppm or more of zinc.
It can be produced by non-proliferatively stirring and / or shaking yeast in suspension.

In order to carry out the present method, it is necessary to suspend the yeast in a high-concentration zinc-containing liquid containing a large amount of a water-soluble salt of zinc, and agitate and / or shake it non-proliferatively. . In this method, a medium for culturing yeast is not used, but a non-proliferative treatment is performed. In other words, yeast is treated under conditions in which substances necessary for the growth of bacterial cells are substantially absent.

As the zinc salt to be used, any zinc salt, organic or inorganic, can be used as long as it has appropriate water solubility and does not kill the yeast, and can be efficiently taken up in the yeast cells. One or more compounds can be used. Non-limiting examples thereof include: zinc sulfate, zinc chloride, zinc citrate, zinc acetate, zinc tartrate, zinc lactate.

A good result can be obtained even when the amount of the zinc salt added is 50 ppm, but a higher concentration than that, 2,000 ppm or more, particularly preferably 3,000 to 6,000 ppm is suitable. According to the conventional technical common sense, if yeast are treated with a high concentration of zinc, the yeast may be killed, or even if it is not killed, serious serious adverse effects are likely to occur. The present invention is a transcendental one, and, unexpectedly, it was the first time that yeast was not killed by such a high concentration of zinc, but rather it was first succeeded in incorporating it in a large amount. is there. Furthermore, it has been confirmed that treatment with zinc having a high concentration of 10,000 ppm or more is possible.

As a result, 600 to 10 per dry cell,
Finally, we succeeded in incorporating 000 ppm or more of zinc into the yeast cells. Even more surprisingly, according to this method, it is possible to incorporate a very large amount of zinc of 30,000 ppm or more per dry cell into the yeast cell by using a zinc solution of 10,000 ppm. .

The treatment conditions for incorporating zinc into yeast cells are as follows.
The temperature is 0 ° C., preferably 20 to 35 ° C., 1 to 120 hours, preferably 40 to 100 hours, pH 4 to 7, preferably pH 4.5 to 6.5. It may be appropriately determined depending on the concentration, and may be out of the above range in some cases.

The stirring and / or shaking depends on the viscosity of the zinc solution and the yeast content, but it is 500 to 1,000 rpm.
If the stirring is moderate, or the amplitude is 12 cm, 100-
It is recommended to shake at 200 rpm. Good results can be obtained by performing aeration under aerobic conditions. Aeration is performed at about 0.5 to 5 vvm, but if necessary, the range may be deviated.

As described above, a yeast having a high magnesium / zinc content can be created. As a result, 2,000 to 5,000 ppm of magnesium per dry cell,
A novel multi-mineral edible yeast containing 10,000 ppm or more of zinc can be obtained.

Furthermore, by using the thus-produced yeast having a high content of magnesium and zinc as a raw material, the yeast was treated under the above-described conditions for producing a yeast having a high content of iron, and by further containing iron at a high concentration, magnesium and zinc were obtained.・ It is possible to create yeast with high iron content. As a result, magnesium per dry cell is 2,000 to 5,000 ppm and zinc is 1
It is possible to obtain a novel multi-mineral edible yeast containing 10,000 ppm and iron of 15,000 ppm or more.

Examples of the present invention will be described below.

[0047]

EXAMPLE 1 Magnesium sulfate (MgSO ₄ · 7H ₂ O)
And the magnesium ion concentration in the solution is 1,00
Four kinds of magnesium solutions were prepared so as to be 0, 5,000, 10,000, 20,000 ppm, and 1,000 ml of this solution were added with 150 g of baker's yeast (Regular yeast manufactured by Oriental Yeast Co., Ltd.) (15%). concentration)
And suspend it in a 3L jar fermenter at 30 ° C for 1 hour.
Stirring treatment was performed for 20 hours under the conditions of aeration of 1.5 vvm and 651 rpm.

Sampling was performed at predetermined intervals, the cells were collected by centrifugation (3,000 × g, 5 minutes), washed twice with ion-exchanged water (MilliQ), and then the cells were wet-ashed. Magnesium was quantified with an atomic absorption spectrophotometer. In addition, the amount of residual magnesium in the combined supernatant and washing solution after the bacterial cell collection was colorimetrically determined using a magnesium measurement kit (Magnesium B Test Wako). The dry cell weight was calculated by an absolute drying method in which 5 ml of the bacterial solution was dried at 105 ° C. for 5 hours or more, and the weight that reached a constant weight was weighed. The obtained results are shown in FIG.

[0049]

Example 2 Magnesium sulfate (MgSO ₄ · 7H ₂ O)
And the magnesium ion concentration in the solution is 20,000
Prepared to be 0 ppm, 1,000 ml of this solution
100 g (10% concentration) of baker's yeast (Regular yeast manufactured by Oriental Yeast Co., Ltd.) was suspended in a 3 L jar fermenter at 30 ° C. for 120 hours, and the conditions of aeration and stirring were as shown in Table 1 below. Processed.

Sampling was performed at predetermined intervals, the cells were collected by centrifugation (3,000 × g, 5 minutes), washed twice with ion-exchanged water (MilliQ), and then wet-ashed. Magnesium was quantified with an atomic absorption spectrophotometer. In addition, the amount of residual magnesium in the combined supernatant and washing solution after the bacterial cell collection was colorimetrically determined using a magnesium measurement kit (Magnesium B Test Wako). The dry cell weight was calculated by an absolute drying method in which 5 ml of the bacterial solution was dried at 105 ° C. for 5 hours or more, and the weight that reached a constant weight was weighed. The obtained results are shown in Table 1 below.

[0051]

[Table 1]

[0052]

EXAMPLE 3 Magnesium sulphate (MgSO ₄ · 7H ₂ O)
And the magnesium ion concentration in the solution is 20,000
Prepared so as to be 0 ppm, suspend 2.25 kg (15% concentration) of baker's yeast (Regular yeast manufactured by Oriental Yeast Co., Ltd.) in 15 L of this solution, and in a 30 L jar fermenter for 72 hours at 30 ° C. Ventilation 1.5
Stirring treatment was performed under the conditions of vvm and 650 rpm. After treating for a predetermined time, the cells were centrifuged (3,000 xg, 5
Cells) and collect with ion-exchanged water (MilliQ) for 2
After washing twice, the cells were wet-ashed, and magnesium was quantified by an atomic absorption spectrophotometer. As a result, the concentration of magnesium per dry cell was 10,500 ppm. The dry cell weight was calculated by an absolute drying method in which 5 ml of the bacterial solution was dried at 105 ° C. for 5 hours or more, and the weight that reached a constant weight was weighed.

The magnesium-rich yeast thus obtained was used as a raw material yeast, and zinc sulfate (ZnSO ₄ .7H
₂ O), zinc ion in solution is 5,000 ppm
The solution was prepared so that 1.5 g of the zinc solution contained 300 g of magnesium-rich yeast (2 × 10 ⁹ cells / m 2).
1) was suspended and stirred in a 3 L jar fermenter with aeration of 2.0 vvm and 650 rpm, and treated at 30 ° C. for 72 hours under non-growth conditions.

After aeration and stirring for a predetermined time, the bacterial cells were collected by centrifugation (3,000 xg, 5 minutes), washed twice with ion-exchanged water (MilliQ), and then wet-ashed. Table 2 shows the results of quantifying magnesium and zinc with an atomic absorption spectrophotometer.

[0055]

[Table 2]

[0056]

Example 4 Yeast with a high magnesium content obtained in Example 3 (the magnesium concentration in the cells was 10 per dry cell,
500ppm) as raw material yeast, ferrous sulfate (FeSO
₄ ), divalent iron ions in the solution are 5,000pp
A solution was prepared so that the amount of water would be m, and to this iron solution 1.5 L, 300 g of magnesium-rich yeast (2 × 10 ⁹ cells / m 2
1) was suspended, and the mixture was gently stirred in a 3 L jar fermenter at 200 rpm until yeast did not settle, and treated at 30 ° C. for 24 hours under non-growth conditions.

After stirring for a predetermined time, the cells were collected by centrifugation (3,000 × g, 5 minutes), washed twice with ion-exchanged water (MilliQ), wet-ashed, and atomized. The results of quantifying magnesium and iron by an absorption spectrophotometer are shown in Table 3 below.

[0058]

[Table 3]

[0059]

Example 5 Ferrous sulfate (FeSO ₄ ) was used as a raw material yeast with the magnesium / zinc-rich yeast obtained under the conditions described in Example 3, and divalent iron ions were added to the solution.
A solution was prepared so as to have a concentration of 000 ppm, and 300 g of raw material yeast (2 × 10 ⁹ cells / m 2) containing a high concentration of magnesium and zinc prepared in advance in 1.5 L of this iron solution.
l) and suspend in a 3 L jar fermenter for 30
The mixture was gently stirred at 200 rpm for 24 hours at 200 ° C. at which yeast did not settle.

After stirring for a predetermined time, the cells were collected by centrifugation (3,000 xg, 5 minutes) and washed twice with ion-exchanged water (MilliQ), and then the cells were wet-ashed and atomized. Magnesium, zinc and iron were quantified by an absorption spectrophotometer. The results obtained are shown in Table 4 below.

[0061]

[Table 4]

[0062]

[Example 6] Using the magnesium-rich yeast obtained in Example 3, a bread-making test was conducted with the composition of bread shown in Table 5 below. As a control, baker's yeast (Oriental Yeast Industry Co., Ltd.) was used as a raw material yeast for the magnesium-rich yeast.
(Regular yeast made by) was used. The bread was wet-ashed and the amount of magnesium was determined by an atomic absorption spectrophotometer. The obtained results are shown in Table 6 below.

[0063]

[Table 5]

[0064]

[Table 6]

[0065]

Example 7 Into a 1 L Sakaguchi flask, 200 ml of the medium shown in Table 7 below was placed, and baker's yeast (Regular yeast manufactured by Oriental Yeast Co., Ltd.) was inoculated (the initial amount of cells was 0. 02% (about 4 × 10 ⁶ pieces / ml), shake at 30 ° C. for 24 hours (amplitude 12 cm, 110)
(rpm) and cultured.

[0066]

[Table 7]

Centrifugation of the cells after shaking (3,000 x
g, 5 minutes) to collect the bacteria, and deionized water (Milli)
After washing twice with Q), the bacterial cells were wet ashed, and magnesium was quantified by an atomic absorption spectrophotometer. In addition, the amount of residual magnesium in the combined supernatant and washing solution after the bacterial cell collection was colorimetrically determined using a magnesium measurement kit (Magnesium B Test Wako). The obtained results are shown in Table 8 below.

[0068]

[Table 8]

[0069]

[Example 8] Based on the conditions of Example 7, the magnesium concentration in the culture solution was changed, and the magnesium concentration in the obtained bacterial cells was measured by the method described in Example. The results shown in Table 9 below were obtained. Obtained. The phosphorus source is potassium dihydrogen phosphate (K
H ₂ PO ₄ ), and the amount of phosphorus added was 20% with respect to glucose.

[0070]

[Table 9]

[0071]

Example 9 Using a 3L jar fermenter, baker's yeast (Regular yeast manufactured by Oriental Yeast Co., Ltd.) was used under the conditions for culturing ordinary baker's yeast. The aeration was 1.5 vvm, the stirring was 650 rpm, and the culture temperature was 30 ° C. A 25% solution of glucose was prepared and initially added or fed.

The medium composition was based on Example 7, the phosphorus source was potassium dihydrogen phosphate (KH ₂ PO ₄ ), and was 20% with respect to glucose. However, the initial yeast concentration is 2%
(About 4 × 10 ⁸ cells / ml), and the culture time was 24 hours. Magnesium added to the initial culture is 250-1,
The concentration was set to 000 ppm, and magnesium sulfate (MgSO ₄ .7H ₂ O) was used as a magnesium source. The results obtained are shown in Table 10 below. The concentration of magnesium added is 1,000
The yield with respect to sugar at a concentration other than ppm was as good as 130% or more, and was 115% even when 1,000 ppm was added.

[0073]

[Table 10]

[0074]

Example 10 Yeast obtained in Example 9 (50 in the medium)
(0 ppm of magnesium added) was used as a seed yeast, and further cultured under the conditions of Example 9. The initial addition amount of magnesium was set to 500 ppm.

As a result, the yield of sugar against baker's yeast was 76.8.
%, And the growth was slightly inhibited, but the intracellular magnesium concentration was remarkably increased to 38,270 ppm per dry cell.

Yeast with a high magnesium content obtained under the same conditions as in Example 9 (medium added with 500 ppm of magnesium, the concentration of magnesium in the cells was 7,000 ppm per dry cell) was used as the starting yeast. , Zinc sulfate (ZnSO ₄ .7H ₂ O) was used to prepare a solution such that zinc ion was 5,000 ppm in the solution.
X 10 ⁹ cells / ml) and suspended in a 3 L jar fermenter with aeration of 2.0 vvm and 650 rpm,
Treatment was carried out at 30 ° C. for 72 hours under non-growth conditions.

After aeration and stirring for a predetermined time, the cells were collected by centrifugation (3,000 xg, 5 minutes) and washed twice with ion-exchanged water (MilliQ), and then the cells were wet ashed. The results of quantifying magnesium and zinc by an atomic absorption spectrophotometer are shown in Table 11 below.

[0078]

[Table 11]

[0079]

[Example 11] Yeast with a high magnesium content obtained under the same conditions as in Example 9 (medium added with 500 ppm of magnesium, the concentration of magnesium in the cells was 7,000 ppm per dry cell) was used as a raw material. As the yeast, ferrous sulfate (FeSO ₄ ) was used to prepare a solution so that the divalent iron ion was 5,000 ppm in the solution, and 1.5 g of this iron solution was added with 300 g of magnesium-rich yeast (2 g). ×
10 ⁹ cells / ml) was suspended, and the mixture was gently stirred in a 3 L jar fermenter at 200 rpm so that the yeast did not settle, and treated at 30 ° C. for 24 hours under non-growth conditions.

After stirring for a predetermined time, the cells were collected by centrifugation (3,000 × g, 5 minutes), washed twice with ion-exchanged water (MilliQ), wet-ashed and then atomized. Table 12 shows the results of quantifying magnesium and iron with an absorption spectrophotometer.

[0081]

[Table 12]

[0082]

Example 12 Ferrous sulfate (FeSO ₄ ) was used as a raw material yeast with the magnesium / zinc-rich yeast obtained under the conditions described in Example 10, and divalent iron ions in the solution were 5,000 ppm. Solution was prepared in such a manner that 300 g (2 × 10 ⁹ cells / ml) of raw material yeast containing a high concentration of magnesium and zinc prepared in advance was suspended in 1.5 L of this iron solution, and a 3 L jar fermenter was prepared. At
200 rp at 30 ° C for 24 hours without yeast sedimentation
The mixture was gently stirred at m.

After stirring for a predetermined time, the bacterial cells were collected by centrifugation (3,000 × g, 5 minutes) and washed twice with ion-exchanged water (MilliQ), and then the bacterial cells were wet ashed and atomized. Magnesium, zinc and iron were quantified by an absorption spectrophotometer. The obtained results are shown in Table 13.

[0084]

[Table 13]

[0085]

EFFECTS OF THE INVENTION According to the present invention, it is possible to obtain 2,0 per dry cell.
It was possible for the first time to make yeast contain a large amount of magnesium of 0.00 to 5,000 ppm or more. Such a yeast containing a large amount of magnesium has never been obtained and is a completely novel yeast.

The magnesium-rich yeast produced according to the present invention can be widely used for various purposes, and various foods such as bread, biscuits and miso containing a large amount of magnesium can be obtained. In addition, the cell wall of yeast can be destroyed, the contents can be taken out, and it can be used for the production of various foods and drinks such as juice, ice cream, crackers, and also for the production of feeds and feeds containing a large amount of magnesium. can do.

Furthermore, according to the present invention, various kinds of minerals in addition to magnesium can be contained in yeast in a large amount. Therefore, in addition to magnesium, minerals such as iron and / or zinc can be highly concentrated. It is also possible to create new yeast containing yeast (yeast with high content of multi-minerals), which can be used for various purposes.

[Brief description of drawings]

FIG. 1 shows time-dependent changes in magnesium concentration in a solution and intracellular magnesium concentration.

Claims (7)

[Claims] 1. An edible yeast containing a high concentration of magnesium. 2. Magnesium added per dry cell of 2,000
Edible yeast containing 0 ppm or more. 3. Containing 50 ppm or more of magnesium,
A method for producing an edible yeast containing magnesium in an amount of 2,000 ppm or more per dry cell, which comprises culturing the yeast in the presence of a phosphorus compound containing 4% or more of the amount of sugar used. 4. 2,000 ppm of magnesium per dry cell, characterized in that yeast is suspended and aerobically stirred and / or shaken in a solution containing 5,000 ppm or more of magnesium. Or more, preferably 5,0
A method for producing edible yeast containing at least 00 ppm. 5. Magnesium and zinc characterized by agitating and / or shaking the yeast according to claim 1 or 2 in suspension in a solution containing 50 ppm or more of zinc in a suspension state. A method for producing a large amount of edible yeast. 6. Magnesium, characterized in that the yeast according to claim 1 or 2 is stirred and / or shaken in a suspension state in a non-proliferative manner in a solution containing 2,000 ppm or more of iron. A method for producing an edible yeast containing a large amount of iron. 7. The yeast obtained under the production condition according to claim 5 is stirred and / or shaken in a suspension state in a solution containing iron at 2,000 ppm or more in a non-proliferation state. And a method for producing edible yeast containing a large amount of magnesium, zinc and iron.