JPS6015309B2 - Production method of chromium yeast - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for producing "yeast containing substantial amounts of intracellular chromium" useful as a supplemental dietary source of assimilable chromium when a need for chromium supplementation is indicated.

Although the role of dietary chromium in mammals is not completely understood, substantial symptoms of dietary chromium deficiency are accumulating, with a reduced ability of surrounding tissues to uptake glucose from the blood.

The condition is symptomatically similar to diabetes but is distinguished by the presence of normal amounts of insulin. There is also evidence that normal biological activity of insulin depends on sufficient amounts of chromium. Anabolic chromium deficiency in the diet induces glucose intolerance, as chromium is lost daily through exclusion. That is, some research, for example, the report of Mel
IReview, Vol. 4 eggs o. 2 (1969) pp.
[189-192] showed that administration of a low chromium diet to rats over several weeks resulted in progressive impairment of intravenous glucose tolerance.

The observed impaired glucose tolerance is due to the glucose tolerance factor [GimoseToleranceFactor (GT
F)] is eliminated by supplementing the basal feed with a small proportion of brewer's yeast, which provides an unknown substance called F).

As a result of the research, “the improved GT that was observed earlier”
"F activity" refers to the amount of organic 3 present in the added brewer's yeast.
It was suggested that this was caused by chromium fluoride. Additional experiments showed that the form of chromium in brewer's yeast is easily assimilated, but supplementation with inorganic chromium salt supplemented diets does not achieve comparable effectiveness. More specifically, inorganic chromium salts added to the diet or even chromium naturally occurring in some feeds, such as commercial animal feed, are ineffective in preventing impairment of glucose tolerance and the chromium in the commercial animal feed is ineffective in preventing impairment of glucose tolerance. is an unavailable form. Recently, Anderson et al.
price derson, etal, thejo river female l of
A bait ic mountain rat I Food, Chemistry, w
ol. 28mo, 5 (1978) pp. 1219-21]
A similar confirmatory study was reported by.

It was observed that depending on the chemical form of chromium present, chromium assimilation is different from that of other trace elements. Specifically, natural organic chromium rust isolated from brewer's yeast or certain other natural products differs from simple inorganic chromium compounds in terms of solar absorption rate, tissue distribution, and other effects. was recognized. When chromium deficiency occurs, high amounts of inorganic chromium compounds are required in supplementary diets to restore sufficient chromium levels, whereas organically bound chromium compounds are required to counteract the nutritional deficiency. is a much lower amount. Therefore, it was concluded that the total amount of chromium in the diet is meaningless as an indicator of the nutritional status of chromium in animals. Brewing yeast (Saccharomyces swamm)
) is known to contain small amounts of organically bound chromium available, although the concentrations are usually quite low) (
Yeast solids of 2-4 ml per evening.

Furthermore, in view of the fact that the chromium concentration in brewer's yeast is low and variable, the use of brewer's yeast in high amounts in the diet is not necessarily practical. Other forms of commercial yeast such as baker's yeast or Saccharomyces cerevisiae
myces cerevisiae) and torra (T.
or mountain a) is characterized by being essentially chromium-free. The organically bound chromium found in brewer's yeast is well known to be assimilable and effective as a dietary chromium source to cure chromium deficiency and impaired glucose tolerance, so it is used in small amounts as a dietary supplement. It would be desirable to provide replenishing chromium in concentrated use form.

Initial plans to grow yeast, such as baker's yeast, in media enriched with the addition of inorganic chromium salts did not achieve the desired increase in organically bound intracellular chromium.

Furthermore, it was observed that increasing the concentration of chromium salt in the medium did not cause a quantitative increase in the amount of organically bound chromium within the cells. Therefore, one object of the present invention is to provide a method for producing chromium yeast with increased intracellular chromium content.

Another object is to provide a process for producing yeast containing organically bound chromium in assimilable form in commercial quantities. Another object is to provide a method for producing edible yeast-containing foods with a high intracellular chromium content useful as a dietary supplement for chromium-deficient conditions.

Still another object is to provide a highly assimilable chromium-containing food useful as a dietary supplement to cure glucose intolerance due to chromium deficiency.

The ultimate objective is to provide an essentially uniformly distributed intracellular chromium-containing yeast food product. The foregoing objectives are achieved by a method for producing a chromium yeast product with a high content of intracellular organically binding chromium; During the processing phase,
The active cells of the yeast in the aqueous suspension are contacted under controlled acidic pH conditions of pH 4 or higher, whereby a substantially significant degree of chromium is introduced into the yeast in an amount higher than the final intended amount. absorption into the yeast cells, followed by the growth phase of the yeast cells, and at the same time adding nutrients to reduce the intracellular chromium content of the yeast cells to the final expected chromium content, and Collect,
thickening and washing to remove extracellular torque salts from the yeast;
It consists of sterilizing and drying the yeast cell population to produce a dry yeast granular product.

More particularly, the present invention provides other broad aspects of the invention including the following steps: 'a} Adjusting the pH of an aqueous suspension of live yeast cells to about 4 to 7; {b} Adding to a solid population of yeast cells; Treating the aqueous suspension of the live yeast cells with a water-soluble non-toxic chromium salt at a chromium ion concentration below that at which a yeast growth inhibition reaction is observed; The suspension is maintained only during an essentially non-viable pretreatment period during which intracellular uptake is sufficient; , thereby diluting the intracellular chromium content of the yeast to a predetermined extent; [e' collecting and enriching the yeast cells from the aqueous growth medium; 'f' washing the recovered yeast cells to A process for producing chromium yeast comprising: removing exochromium salts; and) sterilizing and drying the washed yeast cell population containing a substantial amount of chromium ions.

In another broad aspect of the invention, the invention also adjusts the pH of the aqueous suspension of live yeast cells to about 4 to about 7; based on the yeast cell population to about 200 to 8.
Treating the aqueous suspension of the live yeast cell population with a water-soluble non-toxic chromium salt at a chromium ion concentration of 0.00 Sanyu; at least until the yeast cell population has absorbed a substantial amount of chromium ion intracellularly; maintaining the yeast cells in contact with chromium ions at the pH level in the medium under essentially non-viable conditions for a period of about 5 to 3 minutes; recovering the yeast cells from the aqueous medium; wash the collected yeast cells to remove extracellular chromium salts;
The present invention also relates to a method for producing a chromium yeast product with a high intracellular chromium content, which comprises sterilizing and drying the washed yeast cell population containing a substantial amount of intracellular chromium ions.

The yeast used in the method of the invention is preferably a food grade or edible yeast, most preferably Saccharomyces cerevisiae.

Other yeasts that can be used are Toral and brewer's yeasts such as Saccharomyces carluspergensis.
cescarlsberge ship is), the preferred name being S. Includes S. uvarum. The chromium salts used for the treatment of seed yeast are water-soluble, non-toxic chromium salts, among which chromium chloride hexahydrate (C, 3 and 2)
0) is preferred but other chromium salts such as bromide,
Acetates, nitrates or the like are also used.

The amount of chromium salt used during absorption or in the pretreatment phase is from about 200 to 8,000 meta, preferably from about 500 to about 6,000 meta, and most preferably from about 1
The amount should be sufficient to provide a chromium ion concentration of 0.000 to 4000 A. yeast during the pretreatment or absorption step or period.

Chromium absorption is critically influenced by the following factors: time, chromium ion, yeast cell concentration and pH. The pretreatment or imbibition period is essentially a non-growing period in which the yeast cells are in an aqueous suspension in the presence of dissolved chromium salts. The pretreatment or absorption period is at least about 5 minutes or preferably about 5 to 30 minutes. A pretreatment period of 30 minutes or more does not substantially increase the amount of cellular chromium absorbed by the yeast cells. Therefore, extending the pretreatment period is uneconomical. Yeast Growth It is conclusive that adding soluble chromium salts to the seed yeast during fermentation does not result in significant chromium uptake by the yeast cell population.

After pretreatment, the pH of the medium during absorption is essentially acidic, particularly from about 4 to about 7, or preferably from 4 to 6. At a lower pH (e.g. 4-4.5), the absorption amount is
Even after a pre-treatment period of about 30 minutes, it is relatively low. Generally the most preferred pH range is about 5 to about 6. There is very little absorption at pH below about 4.0.

As the pH increases from about 4-4.5 to about 6, the fraction of chlorion absorbed by a given amount of yeast increases. When the intracellular chromium concentration in the seed yeast exceeds about 1,000 m/m, subsequent growth is severely restricted. Therefore, the pH, chromium salt concentration, and yeast concentration in the pretreatment must be adjusted so that the amount of chromium absorbed in the seed yeast is about 1000 μm/ta or less. The growth phase is initiated by adding nutrients to the seed yeast cells when they are subjected to chromium treatment and chromium ion uptake by the yeast essentially reaches a maximum or equilibrates. There is a strong need for intracellular chromium uptake by the seed yeast to reach a higher level than is ultimately desired in the final yeast product. The yeast then grows and absorbs less chromium to reach the desired level. This is believed to ensure that the chromium is in the desired organically bound assimilable form. The growth phase is pH 4.8-5. This is usually carried out preferably in about 5 minutes. The temperature is preferably about 25 to 30 o'clock, and about 29 o'clock
~30°C is also suitable. Nutrients include carbohydrate or carbon sources such as molasses.

Examples of other nutrients are potassium chloride (KC), magnesium sulfate (MgS04, 7 days 20) and nitrogen sources, as well as phosphoric acid sources such as ammonium dihydrogen phosphorus [(NH4) day 2 P04], ammonia and phosphoric acid. . The pH during the growth period after the absorption treatment is completed is adjusted to about 5.

Yeast growth is allowed to continue for a sufficient period of time until the intracellular chromium content of the yeast reaches the desired level. Typically, the yeast cell increase will be at least a 2-fold (100% increase) to about a 7-fold increase, but preferably a 4-fold increase. Fermentation and yeast growth to achieve the increase usually takes place over a period of at least about 4 to about 17 hours. Recovering the yeast from the fermentor after the yeast cell population has increased during the growth phase to produce a yeast cell population with a desired predetermined amount of intracellular chromium levels (e.g., 40-200 r/night of yeast cells as a preferred example). The solution is concentrated by centrifugation or other equivalent means and washed with water to remove extracellular inorganic chromium salts and other dissolved materials.

Production of washed yeast cells with substantial amounts of intracellular chromium The creamed yeast is then sterilized and dried in a drum dryer to kill the yeast.

The resulting yeast powder is packaged (or tabletted) and sold to consumers as edible yeast that can be used as a dietary supplement consisting of organically bound assimilable chromium. A series of experiments were conducted to determine the effect of pH on chromium ion uptake by seed yeast within a 30 minute period of pretreatment and are included in the examples below. Example 1 In this example, an aqueous suspension of seed yeast with a solids content of 1% was treated with chromic chloride (C Niso 3/Bait 20) at a concentration of 190/2 at various pH values.

The results are shown in Table 1. The absorption rate indicates the analytical value of the amount of intracellular absorbed chromium in yeast compared to the initial yeast concentration in the pretreatment step. Table 1: Effect of pH on the amount of Cr+3 absorbed by yeast
It is clear that H is unsatisfactory.

The best results have been obtained at pH 5 and above. Example 2 This example shows a second pretreatment experiment conducted to demonstrate the effect of initial chromium ion concentration on the final intracellular chromium content of yeast cell populations.

The experimental conditions were the same as in Example 1, except that the amount of chromium used in the pretreatment was varied as shown in Table B, and the pretreatment pH was 5.25. The results are shown in Table B;
Table □ The above results show that chromium uptake by the seed yeast during the pretreatment period is proportional to the chromium concentration, but the benefit decreases as the chromium concentration increases further.

The following examples illustrate the experimental implementation of the method of the invention in which the pretreatment phase is followed by a growth phase.

Example 3 This example illustrates the process of the present invention when varying the pH during the pretreatment period.

The usage conditions are as described in the following formula, and the results are shown in Table m. Formula: Hakama Honey: 758 yen with a Brix degree of 85o is added in increasing quantities over 161/incubation time Seed yeast: Baker's yeast (Saccharomyces cerevisiae) is used in the indicated amount Initial volume: 3400' Final volume: approx. 5000 [Salts: KCZ and M 04 and 740 respectively at 1.7 pm; (N ratio) day 2P04 to 16.8 CrC So 3 and 20: to the initial volume containing seed yeast 3 minutes before addition. pH at the time of pretreatment with addition of 0.5 tater: 5.2 or 4.0 pH of growth phase
: 5.25 Temperature: 29±1°C Growth time: 1 beat hour Number of washes: 4 Typical analysis values of the final yeast product: Moisture 3-6% Protein (N% x 6.25) 40-58% Phosphorus Acid salt (as P2Q) 1.7-3.5% chromium
40-200 meta/ta yeast solids Table m Experiments A and C demonstrate the reproducibility of the experimental results.

Fermentative growth was approximately 6-fold increased in all cases. It can be clearly observed (from a comparison of experiment B with experiments A and C) that the pH value during pretreatment is a determining factor for the amount of chromium in the final yeast product. Additional experiments have shown that adding chromium salts to seed*yeast immediately before the start of nutrient addition results in a significant reduction in the amount of chromium in the final yeast product.

Example 4 This example illustrates the method of the invention carried out by varying the seed yeast concentration as shown in Table W.

Other conditions were the same as in Example 3. Table W The above results show that if the seed yeast absorbs about 1,000 mt or more of chromium per yeast solid overnight, the number of viable yeast decreases.

The above experiments show that if the amount of intracellular cross-absorption by the seed yeast is within the experimentally normal range of 1000 ta or less per yeast solid population per night, normal growth of yeast under typical fermentation conditions will not be inhibited (i.e., one beat per beat). This example illustrates that there is approximately a 7-fold increase in the yeast population over time.

However, an increase in chromium ion uptake by seed yeast (at a level of about 1000 cells per night of yeast cells or higher) has been observed to result in a substantial deviation from the expected normal growth; Yeast growth can be essentially completely inhibited at chromium ion levels. Example 5 This example demonstrates the effect of length of fermentation time on yeast growth and experimental results on the chromium content of the resulting yeast product.

The formula for use is as follows:Formula: Pretreatment: Initial volume...360 gallons (1363 so)
Seed yeast solid population...34.2 pounds (15.5k9) CnC〆3 ・Kuse day 20...270 tahiro time at pH 5.25...3 minutes Fermentation: Added salt...KC So and MgSQ・, 740
1.4 pounds (0.6 kg) each Bran Honey...620 pounds (281k9) of Brix degree 85o is added in increasing amounts over 1 hour Phosphoric acid...7.2 pounds (3.3k9) is added to the first 3 Add ammonium hydroxide in increasing amounts within hours...53.6 pounds (24.3k9) at the beginning of 9. Table V shows the results of adding sulfuric acid in increasing amounts within a certain amount of time...Using as much as necessary for pH adjustment: Table V (Note) *The above results are based on the intracellular chromium ion in the yeast without measurement. This indicates that chromium is diluted by yeast growth and that little, if any, chromium is taken up by the yeast from the medium during fermentation or the growing season.

Example 6 This example illustrates the method of the invention in a large scale operation.

・This method was implemented on a large scale.

The results are shown in the table below and can be compared with the results obtained in Example 5. Form: Pretreatment: Initial volume...29,000 gallons (109,774
Evening) Seed yeast solid group...3000 lbs (1361k9) C°C Evening 3・Feed 20...46 lbs (21k9) pH 5
．． Slicing time at 25:30 minutes Fermentation: Added salts
・KC〆and MgS04/740 each 100 pounds (4
5k9) Bran Honey...44,600 lbs (2023k9) of Brix degree 850 is added in increasing amounts for one hour or more. Phosphoric acid...660 lbs (299k9) is added within the first 3 hours.Ammonium hydroxide...4500 lbs (2041k9) ) is added in parallel with the rice bran syrup. Sulfuric acid...add as much as necessary to adjust the pH.

Claims (1)

Claims: 1(a) adjusting the pH of an aqueous suspension of live, edible, food grade yeast cells from about 4 to about 7; (b)
(c) treating the aqueous suspension of the live yeast cell population using a water-soluble non-toxic chromium salt at a chromium ion concentration below that at which a yeast growth inhibition reaction is observed based on the yeast cell population; maintaining said suspension only during an essentially non-viable pretreatment period during which substantial intracellular uptake of chromium by the cell population is sufficient;
d) adding yeast growth nutrients to the chromium-treated yeast-containing aqueous medium to promote growth of the yeast, thereby diluting the intracellular chromium content of the yeast to a predetermined level; (e)
recovering and enriching the yeast cell population from an aqueous growth medium; (f) washing the recovered yeast cell population to remove extracellular chromium salts; and (g) said wash containing a substantial amount of intracellular chromium ions. A method for producing a chromium yeast product, which comprises sterilizing yeast cells and drying them. 2. The method of claim 1, wherein the pretreatment period is at least about 5 minutes. 3. The method of claim 2, wherein the pretreatment period is at least about 5 to about 30 minutes. 4. The method according to claim 1, wherein the pH of the medium is maintained at about 5 to 6 during the non-growth pretreatment period. 5. The method of claim 1, wherein the chromium ion concentration in the medium during the pretreatment period is about 500-6000 μg/g based on the yeast cell population. 6 The pH of the chromium-treated yeast-containing medium is approximately 4 during the growth period.
．． 5. The method according to claim 1, wherein the ratio is adjusted to 5 to 5.5. 7. A method according to claim 1, characterized in that the growth period is sufficient to bring the number of yeast cells to at least 2 cultures. 8. The method according to claim 1, wherein the intracellular chromium ion content of the recovered yeast cell population is at least 40 ppm. 9. The method of claim 1, wherein the growth period is maintained for about 4 to about 17 hours. 10. The method according to claim 1, wherein the yeast is Saccharomyces cerevisiae. 11. The method according to claim 1, wherein the yeast is brewer's yeast. 12 Steps: (a) Adjusting the pH of an aqueous suspension of live, edible, food-grade yeast cells from about 4 to about 7; (b)
(c) treating an aqueous suspension of the live yeast cell population with a water-soluble non-toxic chromium salt at a chromium ion concentration of about 200-800 μg based on the yeast cell solid population; maintaining the population of yeast cells in contact with chromium ions at the pH level in the culture medium under essentially non-viable conditions for a period of at least about 5 to 30 minutes until the chromium ions are absorbed into the cells; (d) recovering and enriching the yeast cells from an aqueous medium; (e) washing the recovered yeast cells to remove extracellular chromium salts; and (f) reducing the substantial amount of intracellular chromium ions. A method for producing a chromium yeast product containing a high degree of intracellular chromium, the method comprising sterilizing and drying the washed yeast cell group containing the washed yeast cells. 13 Chromium ion concentration is 10 per gram of yeast cell solid population
13. The method according to claim 12, wherein the amount is 00 to 4000 μg. (14) The method according to claim 12, wherein the pH is about 5 to about 6.