WO2011102387A1 - 還元型ピロロキノリンキノンの製造方法 - Google Patents
還元型ピロロキノリンキノンの製造方法 Download PDFInfo
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- WO2011102387A1 WO2011102387A1 PCT/JP2011/053283 JP2011053283W WO2011102387A1 WO 2011102387 A1 WO2011102387 A1 WO 2011102387A1 JP 2011053283 W JP2011053283 W JP 2011053283W WO 2011102387 A1 WO2011102387 A1 WO 2011102387A1
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- ascorbic acid
- pyrroloquinoline quinone
- solution
- reduced
- salt
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D471/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00
- C07D471/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00 in which the condensed system contains two hetero rings
- C07D471/04—Ortho-condensed systems
Definitions
- the present invention relates to a production method of reduced pyrroloquinoline quinone and a reduced pyrroloquinoline quinone obtained by the production method.
- the present invention also relates to a method for stabilizing reduced pyrroloquinoline quinone.
- PQQ Pyrroloquinoline quinone
- Non-patent Document 1 Pyrroloquinoline quinone
- PQQ is present not only in bacteria but also in eukaryotic fungi and yeast, and plays an important role as a coenzyme.
- These PQQs can be produced by an organic chemical synthesis method (Non-patent Document 2), a fermentation method (Patent Document 1), or the like.
- Reduced PQQ has been reported to have much higher antioxidant activity than conventional PQQ (Non-patent Document 3), nutritional functional food, food for specified health use, nutritional supplement, nutritional supplement, beverage, feed, It is a compound useful as an animal drug, cosmetics, pharmaceutical, therapeutic drug, prophylactic drug and the like.
- Reduced PQQ can be obtained by reducing oxidized PQQ using a common reducing agent such as sodium borohydride and sodium hyposulfite, hydrogen reduction with a platinum catalyst, and reduction with glutathione.
- a common reducing agent such as sodium borohydride and sodium hyposulfite
- hydrogen reduction with a platinum catalyst has been reported (Non-Patent Documents 3, 4, and 5).
- a general reducing agent is highly likely to be toxic to the living body, and a process for removing it is necessary.
- ascorbic acid is well known as a substance having an action of reducing a substance. Therefore, a combination of PQQ and ascorbic acid may be proposed as a composition having antioxidative activity.
- the reduced form of PQQ has higher antioxidant activity than ascorbic acid. Reduction with ascorbic acid has been considered difficult.
- reduced PQQ is easily oxidized to oxidized PQQ by molecular oxygen. Therefore, it is necessary to take measures for the storage method.
- the present inventors have found that reduced pyrroloquinoline quinone can be obtained in a high yield from a solution having a pH of 3.5 or less obtained by mixing a pyrroloquinoline quinone solution having a pH of 4 or less and an ascorbic acid solution.
- the present invention is based on this finding.
- the object of the present invention is to provide a method for producing reduced pyrroloquinoline quinone which is highly safe, simple and low in cost, and a reduced pyrroloquinoline quinone obtained by the production method.
- Another object of the present invention is to provide a method for stabilizing reduced pyrroloquinoline quinone.
- a method for producing reduced pyrroloquinoline quinone wherein a solution of pyrroloquinoline quinone or a salt thereof adjusted to pH 4 or less and an ascorbic acid analog are mixed to have a pH of 3 containing reduced pyrroloquinoline quinone.
- a production method comprising a step of obtaining a solution of 5 or less.
- reduced pyrroloquinoline quinone can be produced with high safety, convenience and low cost, and no expensive equipment is required for producing reduced pyrroloquinoline quinone. It is advantageous.
- the present invention is also advantageous in that reduced pyrroloquinoline quinone can be stably stored.
- reduced pyrroloquinoline quinone can be produced by mixing a solution of pyrroloquinoline quinone or a salt thereof having a pH of 4 or less with an ascorbic acid analog to obtain a solution having a pH of 3.5 or less. it can.
- reduced pyrroloquinoline quinone means a compound represented by the following formula (1).
- the pyrroloquinoline quinone (free form) used in the present invention means a compound represented by the formula (2).
- the pyrroloquinoline quinone used in the present invention can be used as a pyrroloquinoline quinone (free form) or a salt of pyrroloquinoline quinone.
- Examples of the “pyrroloquinoline quinone salt” used in the present invention include alkali metal salts, alkaline earth metal salts, and ammonium salts of pyrroloquinoline quinone, with alkali metal salts being preferred.
- the pyrroloquinoline quinone used in the present invention is not particularly limited as long as it is a free form or an alkali metal salt. It is particularly easy to use a free body, a dinatrim body, and a dipotassium body, which are easily available.
- Examples of the alkali metal salt of pyrroloquinoline quinone used in the present invention include salts of sodium, potassium, lithium, cesium, rubidium and the like. Preferably, a sodium salt and a potassium salt are more preferable in terms of easy availability.
- the substitution number of the salt in the alkali metal salt of pyrroloquinoline quinone is 1 to 3, and any of a monoalkali metal salt, a dialkali metal salt, and a trialkali metal salt is preferable, but a dialkali metal salt is preferable.
- disodium salt and dipotassium salt are particularly preferable.
- pyrroloquinoline quinone or a salt thereof used in the present invention a commercially available one can be obtained, and it can be produced by a known method.
- the pyrroloquinoline quinone or a salt thereof used in the present invention can be used as a solution of pyrroloquinoline quinone or a salt thereof.
- the solvent used is not particularly limited as long as the reaction proceeds, and pyrroloquinoline quinone or a salt thereof can be used by dissolving in a solvent such as water, alcohol, dimethyl sulfoxide, etc. Water (aqueous solution) is preferable because it does not cause a problem.
- a solution of pyrroloquinoline quinone or a salt thereof can be prepared to be, for example, 0.001 to 30 g / l, preferably 0.01 to 15 g / l, more preferably 0.1 to 5 g. / L.
- the pH of the solution of pyrroloquinoline quinone or a salt thereof can be adjusted to 4 or less in order to obtain reduced PQQ efficiently. Moreover, in order to raise the solubility of pyrroloquinoline quinone, it can be set to 1 or more.
- the pH of the solution of pyrroloquinoline quinone or a salt thereof is preferably 1 to 4, more preferably 1 to 3.5, still more preferably 2 to 3.5, and still more preferably. 2 to 2.5.
- an acidic substance for example, hydrochloric acid or the like
- an alkaline substance for example, sodium hydroxide or the like
- the ascorbic acid analog is not particularly limited, and for example, ascorbic acid, rhamno-ascorbic acid, arabo-ascorbic acid, gluco-ascorbic acid, fuco-ascorbic acid, glucohepto-ascorbic acid, xyllo-ascorbic acid, galacto-ascorbine
- examples thereof include those similar to ascorbic acid such as acid, gulo-ascorbic acid, allo-ascorbic acid, erythro-ascorbic acid and 6-desoxyascorbic acid. , Calcium salt, etc.).
- L form eg. L-ascorbic acid, sodium L-ascorbate, etc.
- D form eg. D-arabo-ascorbic acid, D-arabo-sodium ascorbate, etc.
- racemate There may be.
- examples include L-ascorbic acid, L-ascorbyl palmitate, L-ascorbic acid stearate, D-arabo-ascorbic acid and the like.
- any of the above ascorbic acid analogs can be suitably used, but considering the ease of separation from the produced reduced pyrroloquinoline quinone, the above ascorbic acid analogs Of these, water-soluble ones are particularly preferred. Most preferred are free forms such as L-ascorbic acid and D-arabo-ascorbic acid from the viewpoints of availability and price.
- ascorbic acid analog used in the present invention a commercially available product can be obtained, or can be produced by a known method.
- the ascorbic acid analog used in the present invention can be used as an ascorbic acid analog or as a solution of an ascorbic acid analog.
- the ascorbic acid analog can be used by dissolving it in a solvent such as water, alcohol or dimethyl sulfoxide, but it is preferably used as an aqueous solution of the ascorbic acid analog.
- the solution of ascorbic acid analog can be prepared to be, for example, 0.1 to 500 g / l, and preferably 0.5 to 100 g / l.
- the step of “mixing a solution of pyrroloquinoline quinone or a salt thereof with an ascorbic acid analog to obtain a solution having a pH of 3.5 or less comprising reduced pyrroloquinoline quinone” comprises pyrroloquinoline It is only necessary to obtain reduced pyrroloquinoline quinone by reacting quinone or a salt thereof with an ascorbic acid analog in a solvent and reducing pyrroloquinoline quinone.
- a solution of pyrroloquinoline quinone or a salt thereof and ascorbic acid can also be performed by mixing with a solution of an analog, or by adding an ascorbic acid analog to a solution of pyrroloquinoline quinone or a salt thereof.
- the above process also includes an aspect in which a solution comprising pyrroloquinoline quinone or a salt thereof and an ascorbic acid analog is orally administered to a mammal and reacted in vivo (for example, oral cavity, stomach, intestine). .
- mixing can be performed by adding one mixing object to the other mixing object, or by adding the mixing object to another container.
- an additive can be added to an addition target at a time or can be gradually added.
- the molar ratio of ascorbic acid analog to pyrroloquinoline quinone or its salt is thought to react with equimolar amounts of pyrroloquinoline quinone or its salt and ascorbic acid analog, and should be determined according to the desired reductant content. Can do. Practically, it is preferable to use 0.5 to 1000 times mole of ascorbic acid analog relative to PQQ. In the case of isolating reduced PQQ, 0.9 to 10 times is preferable. When the content is lower than this range, the expected effect cannot be obtained because the content of the reductant is low. There is no problem if it is added excessively, but if it is too much, the cost becomes high.
- the molar ratio of pyrroloquinoline quinone or a salt thereof to an ascorbic acid analog is 1: 0.5 to 1000, preferably 1: 1.5 to 1000, more preferably in a solvent.
- the ratio may be 1: 1.5 to 100, and more preferably 1: 1.5 to 10.
- the reaction temperature is not particularly limited, but can be, for example, ⁇ 10 ° C. to 180 ° C., and preferably 0 ° C. to 100 ° C.
- the reaction proceeds sufficiently even at room temperature.
- the reaction time is not particularly limited, but can be, for example, 0.2 to 48 hours, and preferably 0.5 to 24 hours.
- Any solvent may be used as long as the reaction proceeds, but an aqueous solution that does not cause a big problem even if it remains in the product is preferable. Since the reaction is difficult to proceed under alkaline conditions, an aqueous solution having a pH of 5 or lower is particularly preferable, and a pH of 4 or lower is more preferable. In order to adjust pH, there is no particular problem in adjusting by adding acid or alkali. What is necessary is just to use it as needed.
- the reaction is not particularly limited, but it is preferably performed in an environment with little oxygen.
- the above operation can be performed in an inert gas such as nitrogen or argon according to a conventional method.
- Reduction of the oxidation reaction can be achieved by substitution with an inert gas, reduced pressure, boiling, or a combination thereof. It is preferable to use at least substitution with an inert gas, that is, an inert gas atmosphere.
- the inert gas include nitrogen gas, helium gas, argon gas, hydrogen gas, carbon dioxide gas, and the like, preferably nitrogen gas.
- the pH of a solution (reaction solution) obtained by reacting a solution of pyrroloquinoline quinone or a salt thereof with an ascorbic acid analog is the pH of a solution of pyrroloquinoline quinone or a salt thereof or ascorbic acid.
- the amount of the analog can be adjusted to pH 3.5 or lower, and the pH can be adjusted to 3 through a step of adjusting pH using an acidic substance (for example, hydrochloric acid) or an alkaline substance (for example, sodium hydroxide). .5 or less.
- the pH of the obtained solution can be 3.5 or less, but is preferably 3 or less, more preferably 2.8 or less, and even more preferably 2.6 or less.
- the production method according to the present invention can be carried out as follows.
- Pyrroloquinoline quinone is prepared at an aqueous solution concentration of 0.01 to 15 g / L. This concentration is described as the concentration at which dissolution occurs, but if it is higher than this, the reaction tends to occur in a suspended state.
- the reaction is completed by a simple operation of mixing ascorbic acid powder or solution here.
- the reaction temperature is usually 0 ° C. to 100 ° C., and the reaction time depends on the temperature, but about 0.2 to 48 hours is easy to use.
- an acid or a base may be added.
- the obtained precipitate can be reduced pyrroloquinoline quinone.
- precipitate means a solid phase (solid) appearing from a liquid phase (solution).
- Precipitate can be separated from the solution.
- a precipitate (deposited reductant) can be obtained by filtration, centrifugation, and decantation. Further, it can be washed with water or alcohol. It is also possible to obtain a solid by drying under reduced pressure. Or it is also possible to provide it as it is without performing such separation operation.
- Recrystallization may be performed by an operation of dissolving in a good solvent such as dimethyl sulfoxide to lower the solubility, specifically lowering the temperature, adding a poor solvent, or concentrating. Further, it can be purified by column chromatography.
- a good solvent such as dimethyl sulfoxide
- the composition contains 0.5 to 1000 times ascorbic acid analog to pyrroloquinoline quinone or a salt thereof.
- it can be generated in a container such as a cup immediately before edible, or can be generated in the oral cavity, stomach, or intestine of a living body.
- compositions containing 0.5 to 1000-fold moles of ascorbic acid analog with respect to pyrroloquinoline quinone or a salt thereof is prepared and used for the above purpose is consistent with the object of the present invention. To do. Whether the composition is in the form of a solid or a solution, it reacts in a solution state when administered orally.
- a method for producing reduced pyrroloquinoline quinone wherein a solution of pyrroloquinoline quinone or a salt thereof having a pH of 2 to 3.5, an ascorbic acid analog or a solution thereof And a process for obtaining a solution having a pH of 3 or less comprising reduced pyrroloquinoline quinone.
- a method for producing reduced pyrroloquinoline quinone comprising a solution of pyrroloquinoline quinone or a salt thereof having a pH of 2 to 2.5, an ascorbic acid analogue or
- This is a production method comprising a step of mixing a solution to obtain a solution having a pH of 2.6 or less comprising reduced pyrroloquinoline quinone.
- the composition containing 0.5 to 1000 moles of ascorbic acid with respect to reduced pyrroloquinoline quinone can suppress oxidation, can be stably stored without purification, and is provided as it is can do. This is one of the excellent points of the production method of the present invention.
- reduced pyrroloquinoline quinone in order to stably store reduced pyrroloquinoline quinone, reduced pyrroloquinoline quinone can be provided as a solution comprising an ascorbic acid analog.
- compositions by adding an ascorbic acid analog after the separation operation.
- This composition can be provided in the form of a solid, a suspension, or a solution, and a composition that is suspended in water can be easily provided from the reaction conditions.
- a method for stabilizing reduced pyrroloquinoline quinone is provided.
- the stabilization method according to the present invention is characterized in that reduced pyrroloquinoline quinone is protected from oxidation by molecular oxygen.
- the stabilization method according to the present invention can stabilize reduced pyrroloquinoline quinone by allowing reduced pyrroloquinoline quinone or a salt thereof together with an ascorbic acid analog in a solvent.
- the molar ratio of reduced pyrroloquinoline quinone and ascorbic acid analog can be 1: 0.5 to 1000, preferably 1: 1 to 500 in a solvent.
- the dosage form of reduced pyrroloquinoline quinone obtained in the present invention is not particularly limited and can be appropriately selected depending on the intended use.
- the composition for oral consumption of the present invention can be used as food, functional food, pharmaceuticals or quasi drugs for humans or animals.
- the functional food here means foods taken for the purpose of maintaining nutrition or supplementing nutrition, such as health foods, nutritional supplements, functional nutritional foods, and nutrition insurance foods. Specific forms include, but are not limited to, capsules, tablets, chewable tablets, drinks and the like.
- additives used in food such as sweeteners, coloring agents, preservatives, thickening stabilizers, antioxidants, coloring agents, bleaching agents, antibacterial and antifungal agents, gum bases Bitterings, enzymes, brighteners, acidulants, seasonings, emulsifiers, fortifiers, manufacturing agents, fragrances, spice extracts and the like can be used.
- it can also be added to ordinary foods such as miso, soy sauce, instant miso soup, ramen, fried noodles, curry, corn soup, merbaudofu, marvo eggplant, pasta sauce, pudding, cake, bread and the like.
- composition for producing reduced PQQ is provided.
- composition for producing reduced PQQ that is resistant to oxidation and can be stably stored is provided.
- a method for producing reduced pyrroloquinoline quinone comprising mixing pyrroloquinoline quinone and ascorbic acid in a solvent.
- the production method according to (1) wherein the solvent is water.
- NMR measurement was performed using a JEOL 500 MHz NMR, JNM-ECA500 spectrum meter, and 13 C-NMR was measured at room temperature.
- UV measurement was performed using a HITACHI U-2000 Spectrophotometer.
- Example 1 The reagent pyrroloquinoline quinone disodium used was a reagent (trade name: Bio PQQ) manufactured by Mitsubishi Gas Chemical Company. L-ascorbic acid manufactured by Wako Pure Chemicals was used.
- Pyrroloquinolinequinone disodium (1.53 g) was dissolved in water (500 g) to a concentration of 0.01 mol / l.
- L-ascorbic acid was dissolved in 1001 g of water to give a concentration of 0.2 mol / l.
- the obtained solid was washed with a degassed aqueous hydrochloric acid solution and dried by a nitrogen stream. Heavy dimethyl sulfoxide was added thereto, and it was placed in an NMR tube under a nitrogen stream, and 13 C-NMR was measured at room temperature.
- Example 2 20 g of pyrroloquinoline quinone disodium solution 0.01 mol / l concentration (pH 3.5) and L-ascorbic acid solution 0.2 mol / l concentration 10 g were mixed (pH 3).
- L-ascorbic acid has a molar amount 10 times that of pyrroloquinolinequinone 1.
- the two solutions were mixed and stirred at room temperature. The color changed immediately and a solid precipitated. After standing at room temperature overnight, the pH was measured with a pH test paper to be 3. The solid was taken out by centrifugation (1000 rpm, 10 minutes) and dried under reduced pressure to obtain 0.073 g of a reduced water-containing solid containing no oxidant. Analysis of the UV spectrum indicated a reduced state.
- Example 3 20 g of pyrroloquinoline quinone disodium solution 0.01 mol / l concentration (pH 3.5) and L-ascorbic acid solution 0.2 mol / l concentration 5 g were mixed (pH 3).
- L-ascorbic acid is 5 times the molar amount of pyrroloquinoline quinone 1.
- the two solutions were mixed and stirred at room temperature. The color changed immediately and a solid precipitated. After standing at room temperature overnight, the pH was measured with a pH test paper to be 3. The solid was removed by centrifugation (1000 rpm, 10 minutes) and dried under reduced pressure to obtain 0.044 g of a reduced solid.
- the isolated crude yield was 66%.
- Example 4 20 g of pyrroloquinoline quinone disodium solution 0.001 mol / l concentration (pH 3.5) and L-ascorbic acid solution 0.2 mol / l concentration 10 g were mixed (pH 2).
- L-ascorbic acid has a molar amount 100 times that of pyrroloquinolinequinone 1.
- the two solutions were mixed and stirred at room temperature. The color changed immediately and a solid precipitated. After being allowed to stand overnight at room temperature, the pH was 2 when measured with a pH test paper. The solid was removed by centrifugation (1000 rpm, 10 minutes) and dried under reduced pressure to obtain 0.006 g of a reduced solid.
- Example 5 A pyrroloquinoline quinone disodium solution 0.01 mol / l concentration (pH 3.5) 0.5 g and an L-ascorbate sodium solution 0.5 mol / l concentration 0.5 g were mixed. The pH at this time was 6-7. L-ascorbic acid is 50 times the molar amount of pyrroloquinolinequinone 1. The two solutions were mixed at room temperature, and the mixed solution was added to 10 ml of artificial gastric juice (pH 1.2). When left at room temperature overnight, a reduced solid precipitated. Reaction becomes easy to advance by making it into acidic conditions. It is also considered that it is reduced in vivo.
- Example 6 1 g of pyrroloquinoline quinone disodium solution 0.01 mol / l concentration (pH 3.5) and L-ascorbic acid solution 0.011 mol / l concentration 1 g were mixed (pH 2.5). The molar ratio at this time is 1: 1.1. By reacting at 30 ° C. for 8 days (pH 2.5), 82% of PQQ reacted to obtain a reduced product-containing product.
- Comparative Example 2 A pyrroloquinoline quinone disodium solution 0.01 mol / l concentration 0.5 g and a sodium L-ascorbate solution 0.5 mol / l concentration 0.5 g were mixed at room temperature. The pH at this time was 6-7. L-ascorbic acid is 50 times the molar amount of pyrroloquinolinequinone 1. When the mixture was allowed to stand at room temperature for 3 days, there was no change in the solution (pH 7), and no reduced product was obtained.
- L-ascorbic acid is 20 times the molar amount of pyrroloquinoline quinone 1.
- the pH was 2 as measured with a pH test paper. This mixed solution was reacted at room temperature overnight (pH 2). After the reaction, a reductant solid was precipitated. In this state, L-ascorbic acid is present in a 15-fold molar amount even when the amount used in the reduction reaction and the amount oxidized in air are taken into consideration. Then, when it preserve
- Example 3 The reductant solid obtained in Example 6 was removed by centrifugation, and the supernatant was discarded and washed with water. This treatment removed L-ascorbic acid. Sodium hydroxide aqueous solution was added here so that it might become pH7. All changed to an oxidant after 30 minutes.
- Example 8 1 g of pyrroloquinoline quinone disodium solution 0.01 mol / l concentration (pH 3.5) and L-ascorbic acid solution 0.014 mol / l concentration 1 g were mixed. When 1 g of this mixed solution was put into a 15 ml container and brought into contact with air, 14% of oxidized PQQ was contained (pH 3). When this oxidized type-containing reduced PQQ was allowed to stand at 30 ° C. for 1 week, it contained 18% oxidized PQQ.
- Example 9 Pyrroloquinoline quinone disodium was dissolved in water and adjusted to 2 g / l. The pH of the aqueous solution was adjusted to pH 1 or less using hydrochloric acid and NaOH. L-ascorbic acid was dissolved in water and adjusted to 4 g / l.
- Example 10 Pyrroloquinoline quinone disodium was dissolved in water and adjusted to 2 g / l. The pH of the aqueous solution was adjusted to pH 2.2 using hydrochloric acid and NaOH. L-ascorbic acid was dissolved in water and adjusted to 4 g / l.
- the above two aqueous solutions were mixed in 0.5 ml containers in a 1.5 m container and reacted at room temperature for 24 hours. The pH after the reaction was 2.6. Thereafter, the obtained mixture was centrifuged (1000 rpm, 10 minutes), and the supernatant was discarded to obtain a solid. The obtained solid was washed with about 9% hydrochloric acid, dissolved in dimethyl sulfoxide, and the reductant yield was calculated by UV measurement and found to be 100%.
- Example 11 Pyrroloquinoline quinone disodium was dissolved in water and adjusted to 2 g / l. The pH of the aqueous solution was adjusted to pH 2.6 using hydrochloric acid and NaOH. L-ascorbic acid was dissolved in water and adjusted to 4 g / l.
- the above two aqueous solutions were mixed in 0.5 ml containers in a 1.5 m container and reacted at room temperature for 24 hours.
- the pH after the reaction was 3.
- the obtained mixture was centrifuged (1000 rpm, 10 minutes), and the supernatant was discarded to obtain a solid.
- the obtained solid was washed with about 9% hydrochloric acid, dissolved in dimethyl sulfoxide, and the reductant yield was calculated by UV measurement and found to be 66%.
- Example 12 Pyrroloquinoline quinone disodium was dissolved in water and adjusted to 2 g / l. The pH of the aqueous solution was adjusted to pH 3.5 using hydrochloric acid and NaOH. L-ascorbic acid was dissolved in water and adjusted to 4 g / l.
- the above two aqueous solutions were mixed in 0.5 ml containers in a 1.5 m container and reacted at room temperature for 24 hours.
- the pH after the reaction was 3.5.
- 100 ⁇ l of concentrated hydrochloric acid was added to adjust the pH to 1.
- the obtained mixture was centrifuged (1000 rpm, 10 minutes), and the supernatant was discarded to obtain a solid.
- the obtained solid was washed with about 9% hydrochloric acid, dissolved in dimethyl sulfoxide, and the reductant yield was calculated by UV measurement and found to be 54%.
- the above two aqueous solutions were mixed in 0.5 ml containers in a 1.5 m container and reacted at room temperature for 24 hours.
- the pH after the reaction was 3.5.
- the obtained mixture was centrifuged (1000 rpm, 10 minutes), and the supernatant was discarded to obtain a solid.
- the obtained solid was washed with about 9% hydrochloric acid, dissolved in dimethyl sulfoxide, and the reductant yield was calculated by UV measurement and found to be 1%.
- the above two aqueous solutions were mixed in 0.5 ml containers in a 1.5 m container and reacted at room temperature for 24 hours.
- the pH after the reaction was 3.5.
- the obtained mixture was centrifuged (1000 rpm, 10 minutes), and the supernatant was discarded to obtain a solid.
- the obtained solid was washed with about 9% hydrochloric acid, dissolved in dimethyl sulfoxide, and the yield of the reduced product was calculated by UV measurement.
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Abstract
Description
(2)ピロロキノリンキノンまたはその塩の溶液が、水溶液である、(1)に記載の製造方法。
(3)ピロロキノリンキノンまたはその塩の溶液のpHが、2~3.5である、(1)または(2)に記載の製造方法。
(4)ピロロキノリンキノンまたはその塩とアスコルビン酸類似体のモル比が、1:0.5~1000である、(1)に記載の製造方法。
(5)アスコルビン酸類似体が、アスコルビン酸、rhamno-アスコルビン酸、arabo-アスコルビン酸、gluco-アスコルビン酸、fuco-アスコルビン酸、glucohepto-アスコルビン酸、xylo-アスコルビン酸、galacto-アスコルビン酸、gulo-アスコルビン酸、allo-アスコルビン酸、erythro-アスコルビン酸、6-デスオキシアスコルビン酸、並びに、これらのエステル体および塩からなる群から選択される、(1)に記載の製造方法。
(6)溶液から還元型ピロロキノリンキノンを分離する工程をさらに含んでなる、(1)に記載の製造方法。
(7)(1)~(6)に記載の製造方法により製造される還元型ピロロキノリンキノン。
(8)アスコルビン酸類似体を含んでなる溶液として提供される、(7)に記載の還元型ピロロキノリンキノン。
(9)還元型ピロロキノリンキノンの安定化方法であって、還元型ピロロキノリンキノンまたはその塩を、アスコルビン酸類似体とともに溶媒中に存在させることを含んでなる、方法。
アスコルビン酸類似体の溶液は、例えば、0.1~500g/lとなるように調製することができるが、好ましくは、0.5~100g/lである。
(1) ピロロキノリンキノンとアスコルビン酸を溶媒中で混合することを特徴とする還元型ピロロキノリンキノンの製造方法。
(2)溶媒が水であることを特徴とする(1)に記載の製造方法。
(3)混合液のpHが5以下であることを特徴とする(1)または(2)に記載の製造方法。
(4)ピロロキノリンキノンに対しアスコルビン酸を0.5から1000倍モル使用することを特徴とする(1)~(3)のいずれかに記載の製造方法。
(5)ピロロキノリンキノンに対しアスコルビン酸を0.5から1000倍モルを含む組成物。
(6)ピロロキノリンキノンが還元型であることを特徴とする(5)記載の組成物。
実施例1
原料のピロロキノリンキノンジナトリウムは三菱瓦斯化学社製の試薬(商品名:バイオPQQ)を使用した。L-アスコルビン酸は和光純薬製を使用した。
ピロロキノリンキノンジナトリウムの飽和水溶液に塩酸を加えpHを1以下にした。赤色個体が析出したのをフィルターでろ過し、ピロロキノリンキノンのフリー体を得た。これに重ジメチルスルホキシドを加え、NMR管につめて、13C-NMRを室温測定した。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度(pH3.5)20gとL-アスコルビン酸溶液0.2mol/l濃度10gを混合した(pH3)。ピロロキノリンキノン1に対してL-アスコルビン酸は10倍のモル量である。この二つの溶液を室温で混合し攪拌した。すぐに色が変わり、固体が析出した。一晩、室温で放置したのち、pHをpH試験紙で測ると3であった。固体を遠心分離(1000rpm、10分間)で取り出し、減圧乾燥して、0.073gの酸化体の存在しない還元体含水固体を得た。UVスペクトルの分析は還元状態であることを示していた。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度(pH3.5)20gとL-アスコルビン酸溶液0.2mol/l濃度5gを混合した(pH3)。ピロロキノリンキノン1に対してL-アスコルビン酸は5倍のモル量である。この二つの溶液を室温で混合し攪拌した。すぐに色が変わり、固体が析出した。一晩、室温で放置したのち、pHをpH試験紙で測ると3であった。固体を遠心分離(1000rpm、10分間)で取り出し、減圧乾燥して、0.044gの還元体固体を得た。単離粗収率は66%であった。
ピロロキノリンキノンジナトリウム溶液0.001mol/l濃度(pH3.5)20gとL-アスコルビン酸溶液0.2mol/l濃度10gを混合した(pH2)。ピロロキノリンキノン1に対してL-アスコルビン酸は100倍のモル量である。この二つの溶液を室温で混合し攪拌した。すぐに色が変わり、固体が析出した。一晩、室温で放置したのち、pHをpH試験紙で測ると2であった。固体を遠心分離(1000rpm、10分間)で取り出し、減圧乾燥して、0.006gの還元体固体を得た。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度(pH3.5)0.5gとL-アスコルビン酸ナトリウム溶液0.5mol/l濃度0.5gを混合した。この時のpHは6-7であった。ピロロキノリンキノン1に対してL-アスコルビン酸は50倍のモル量である。この二つの溶液を室温で混合し、この混合溶液を人工胃液10mlに添加した(pH1.2)。一晩、室温で放置すると還元体の固体が析出した。酸性条件にすることで反応は進行しやすくなる。また、生体内でも還元されると考えられる。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度(pH3.5)1gとL-アスコルビン酸溶液0.011mol/l濃度1gを混合した(pH2.5)。この時のモル比は1:1.1である。30℃で8日間反応することで(pH2.5)、82%のPQQが反応し、還元体含有物を得ることができた。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度0.5gとL-アスコルビン酸ナトリウム溶液0.5mol/l濃度0.5gを室温で混合した。この時のpHは6-7であった。ピロロキノリンキノン1に対してL-アスコルビン酸は50倍のモル量である。混合液を3日間室温で放置したところ、溶液に変化はなく(pH7)、還元体は得られなかった。
実施例7
ピロロキノリンキノンジナトリウム1.53gを水500gに溶かし0.01mol/l濃度にした。L-アスコルビン酸は3.51gを水100gに溶かし0.2mol/l濃度にした。
実施例6で得られた還元体固体を遠心分離で取り出し、上澄みを捨て、水で洗浄した。この処理により、L-アスコルビン酸は除去された。ここにpH7になるように水酸化ナトリウム水溶液を加えた。30分後すべて酸化体に変化した。
ピロロキノリンキノンジナトリウム溶液0.01mol/l濃度(pH3.5)1gとL-アスコルビン酸溶液0.014mol/l濃度1gを混合した。この混合液1gを15ml容器に入れ空気に接触させたところ、酸化型PQQが14%含まれていた(pH3)。この酸化型含有還元型PQQを30℃で1週間放置すると酸化型PQQが18%含まれていた。
実施例9
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH1以下となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH2.2となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH2.6となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH3.5となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH4.3となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
ピロロキノリンキノンジナトリウムを水に溶かし、2g/lに調整した。水溶液のpHは、塩酸およびNaOHを用い、pH7.6となるように調整した。また、L-アスコルビン酸を水に溶かし、4g/lに調整した。
Claims (9)
- 還元型ピロロキノリンキノンの製造方法であって、pH4以下に調整されたピロロキノリンキノンまたはその塩の溶液とアスコルビン酸類似体とを混合させて、還元型ピロロキノリンキノンを含んでなるpH3.5以下の溶液を得る工程を含んでなる、製造方法。
- ピロロキノリンキノンまたはその塩の溶液が、水溶液である、請求項1に記載の製造方法。
- ピロロキノリンキノンまたはその塩の溶液のpHが、2~3.5である、請求項1または2に記載の製造方法。
- ピロロキノリンキノンまたはその塩とアスコルビン酸類似体のモル比が、1:0.5~1000である、請求項1に記載の製造方法。
- アスコルビン酸類似体が、アスコルビン酸、rhamno-アスコルビン酸、arabo-アスコルビン酸、gluco-アスコルビン酸、fuco-アスコルビン酸、glucohepto-アスコルビン酸、xylo-アスコルビン酸、galacto-アスコルビン酸、gulo-アスコルビン酸、allo-アスコルビン酸、erythro-アスコルビン酸、6-デスオキシアスコルビン酸、並びに、これらのエステル体および塩からなる群から選択される、請求項1に記載の製造方法。
- 溶液から還元型ピロロキノリンキノンを分離する工程をさらに含んでなる、請求項1に記載の製造方法。
- 請求項1~6に記載の製造方法により製造される還元型ピロロキノリンキノン。
- アスコルビン酸類似体を含んでなる溶液として提供される、請求項7に記載の還元型ピロロキノリンキノン。
- 還元型ピロロキノリンキノンの安定化方法であって、還元型ピロロキノリンキノンまたはその塩を、アスコルビン酸類似体とともに溶媒中に存在させることを含んでなる、方法。
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US13/578,941 US20120323009A1 (en) | 2010-02-16 | 2011-02-16 | Production method of reduced pyrroloquinoline quinone |
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WO2013073642A1 (ja) * | 2011-11-15 | 2013-05-23 | 三菱瓦斯化学株式会社 | 還元型ピロロキノリンキノンのゲル |
WO2014175327A1 (ja) * | 2013-04-26 | 2014-10-30 | 三菱瓦斯化学株式会社 | 黄色系還元型ピロロキノリンキノン結晶及びその製造方法、並びに、食品、医薬品、ゲル、組成物及び組成物の製造方法 |
WO2019235306A1 (ja) * | 2018-06-05 | 2019-12-12 | 三菱瓦斯化学株式会社 | 飲料、飲料の製造方法又は組み合わせ |
WO2020189753A1 (ja) * | 2019-03-20 | 2020-09-24 | 三菱瓦斯化学株式会社 | ピロロキノリンキノン分析方法 |
JPWO2019082548A1 (ja) * | 2017-10-25 | 2020-11-12 | 三菱瓦斯化学株式会社 | ピロロキノリンキノン含有酸性飲料及びピロロキノリンキノンの析出抑制方法 |
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JP6825330B2 (ja) * | 2016-11-25 | 2021-02-03 | 三菱瓦斯化学株式会社 | オートファジー誘導剤 |
KR20210052433A (ko) * | 2018-08-30 | 2021-05-10 | 미쯔비시 가스 케미칼 컴파니, 인코포레이티드 | 광열화억제제, 그것을 포함하는 음료, 및 광열화억제방법 |
US11471426B2 (en) * | 2019-10-16 | 2022-10-18 | American River Nutrition, Llc | Compositions comprising quinone and/or quinol and methods of preparations and use thereof |
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EP3777554A4 (en) * | 2018-06-05 | 2022-01-05 | Mitsubishi Gas Chemical Company, Inc. | BEVERAGE, BEVERAGE PRODUCTION PROCESS OR COMBINATION |
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US20120323009A1 (en) | 2012-12-20 |
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CN102770432A (zh) | 2012-11-07 |
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