WO2014175036A1

WO2014175036A1 - Gas phase substance degradation body, gas phase substance degradation unit, gas phase purification method, and method for manufacturing gas phase substance degradation body

Info

Publication number: WO2014175036A1
Application number: PCT/JP2014/059884
Authority: WO
Inventors: 悠司豊田; 直毅田中; 岸　達也
Original assignee: 日東電工株式会社
Priority date: 2013-04-22
Filing date: 2014-04-03
Publication date: 2014-10-30
Also published as: TW201512277A; JP2014212800A

Abstract

The purpose of this invention is to provide a gas phase substance degradation body, a gas phase substance degradation unit comprising the gas phase degradation body, and a gas phase purification method using the gas phase substance degradation unit, with all of which designated substances such as harmful chemicals in a gas phase can be degraded and removed with good selectivity and high efficiency. Moreover, this invention relates to a method for manufacturing a gas phase substance degradation body in which the abovementioned gas phase substance degradation body can be manufactured inexpensively. Furthermore, another purpose of this invention is to provide a gas phase substance degradation body and a gas phase substance degradation unit with which designated substances such as harmful chemicals in a gas phase can be degraded and removed with good selectivity and high efficiency even when stored for long periods of time and which can maintain this operation over long periods of time. This invention is a gas phase degradation body characterized in that it is formed from a mixed liquid comprising a polyvinyl-alcohol-based resin, a yeast-derived gas phase substance degradation enzyme, and water.

Description

Vapor phase material decomposition product, gas phase material decomposition unit, gas phase purification method, and gas phase material decomposition product manufacturing method

The present invention relates to a gas phase substance decomposition product formed from a mixture containing a specific enzyme capable of decomposing harmful chemical substances such as formaldehyde, polyvinyl alcohol (PVA) resin and water, and a gas containing the gas phase substance decomposition product. The present invention relates to a phase material decomposition unit and a gas phase purification method using the gas phase material decomposition unit. The present invention also relates to a method for producing the gas phase substance decomposition product.

For the capture of harmful chemical substances such as formaldehyde, conventionally, sensory deodorization method using masking action of aromatic deodorants, sterilization biological deodorization method using bactericidal action with soap, digestive enzyme, Biological deodorization method that captures and decomposes using yeast, physical deodorization method that adsorbs and captures on the surface of porous materials such as activated carbon, and chemical deodorization method that captures and decomposes by chemical reaction Are known. Among these, the chemical deodorization method is considered to be an effective method together with the physical deodorization method.

Further, as a method for removing formaldehyde in the indoor environment, a method using an adsorbent that adsorbs formaldehyde and a method for decomposing and removing formaldehyde with a photocatalyst are known. However, in the method using an adsorbent, the adsorbed formaldehyde may be re-released. In the method using a photocatalyst, a light source is required, so a space that is not exposed to much light, for example, furniture interior or air conditioner interior. There was a problem that it could not be used, and neither method was sufficient.

For this reason, various methods for removing formaldehyde other than the above methods have been studied, and as one of them, a method using a microorganism that decomposes formaldehyde is known. For example, a formaldehyde decomposing method characterized by using a mold having formaldehyde decomposing ability (see, for example, Patent Document 1) or a formaldehyde removing agent in which a microorganism-derived formaldehyde degrading enzyme is immobilized on a carrier whose surface is modified with an amino group Is disclosed (for example, see Patent Document 2). Moreover, an aldehyde removal filter formed by adsorbing formaldehyde oxidoreductase on the surface of activated carbon or the like is disclosed (for example, see Patent Document 3).

JP 2003-52355 A JP 2005-131567 A JP 2001-340436 A

However, none of the patent documents discloses any enzyme derived from yeast. In addition, the methods disclosed in these Patent Documents 1 to 3 have a problem in that manufacturing a removal filter or the like is expensive.

An object of the present invention is to provide a gas phase substance decomposition product capable of efficiently decomposing and removing a specific substance such as a harmful chemical substance in the gas phase with good selectivity, a gas phase material decomposition unit including the gas phase material decomposition product, and the It is to provide a gas phase purification method using a gas phase material decomposition unit, and to provide a method capable of manufacturing the gas phase material decomposition product at low cost.

Another object of the present invention is to be able to decompose and remove specific substances such as harmful chemical substances in the gas phase with high selectivity and high efficiency even when stored for a long time, and to maintain such an action for a long time. It is another object of the present invention to provide a gas phase material decomposition product and a gas phase material decomposition unit that are capable of achieving high heat resistance.

That is, the present invention relates to a gas phase substance decomposed material formed from a mixed solution containing a polyvinyl alcohol-based resin, a yeast-derived gas phase substance decomposing enzyme, and water.

It is preferable that the polyvinyl alcohol-based resin forms a supporting substrate, and the yeast-derived gas phase substance-degrading enzyme is dispersed in the supporting substrate.

The polymerization degree of the polyvinyl alcohol resin is preferably 100 to 3000. The saponification degree of the polyvinyl alcohol resin is preferably 85 to 100 mol%.

The content ratio of the gas phase material decomposing enzyme is preferably 0.0001 to 5% by mass based on the total amount of the gas phase material decomposing substance.

The gas phase material decomposition product of the present invention is preferably in the form of a sheet.

It is preferable that the yeast-derived gas phase substance-degrading enzyme is obtained by crushing yeast.

Further, the present invention provides a vapor phase substance decomposition unit characterized in that the vapor phase substance decomposition product is provided on a substrate so as to be in contact with the gas phase, and the vapor phase substance decomposition unit is in contact with the gas phase. The present invention relates to a gas phase purification method.

Furthermore, the present invention includes a step of applying a mixed solution containing a polyvinyl alcohol-based resin, a yeast-derived gas phase substance-degrading enzyme, and water on a substrate to form a coating film, and a step of drying the coating film. It is related with the manufacturing method of the gaseous-phase material decomposition body characterized by including.

It is preferable that the mixed solution is obtained by mixing a yeast crushing extract containing a gas phase substance-degrading enzyme obtained by crushing yeast and a polyvinyl alcohol resin solution.

The vapor phase substance decomposition product of the present invention can decompose and remove specific substances such as harmful substances with high selectivity and high efficiency, and can purify the gas phase such as air. Therefore, the vapor phase substance decomposition product and the gas phase substance decomposition unit of the present invention are effectively used in an environment where functions such as deodorization countermeasures, sick house syndrome prevention, allergy prevention, and chemical substance hypersensitivity suppression are required. be able to.

In addition, a gas phase material degradation product using a yeast-derived gas phase material degrading enzyme has heat resistance.

Furthermore, in the method for producing a gas phase material decomposition product according to the present invention, the gas phase material decomposition product according to the present invention having the above-described effects can be produced at low cost.

It is a figure which shows the formaldehyde gas decomposition | disassembly experiment result in an Example. It is a figure which shows the heat resistance test result in an Example.

1. Vapor phase material decomposition product The gas phase material decomposition product of the present invention is formed from a mixed solution containing polyvinyl alcohol (PVA) resin, a gas phase material decomposition enzyme derived from yeast (yeast), and water. And

(1) Gas-phase substance degrading enzyme Any gas-phase substance-degrading enzyme that can be used in the present invention can be used as long as it is derived from yeast and can degrade (react) a specific substance in the gas phase. It is.

The gas phase substance that is decomposed by the enzyme or reacts with the enzyme is not particularly limited, and examples thereof include aldehydes and carboxylic acids. Among these, particularly harmful Organic substances are mentioned as the object. Examples of such gas phase substances include acetaldehyde, formaldehyde, trichloroacetaldehyde (chloral), benzaldehyde, orthonitrobenzaldehyde, propionaldehyde, n-butyraldehyde, thiophene aldehyde, formic acid, acetic acid, propionic acid, oxalic acid, malonic acid. , Succinic acid, or a mixture of two or more thereof. The form of these gas phase substances may be any of gas, mist, and fine aerosol.

Any enzyme can be used as the enzyme used in the present invention as long as it can decompose (react) the gas phase substance. For example, one or two selected from the group consisting of aldehydes and carboxylic acids Preferred are enzymes using the above substances as substrates. Examples of such an enzyme include one or more selected from the group consisting of alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), aldehyde oxidase, and alcohol oxidase. Among these, ADH, ALDH, and aldehyde oxidase are most useful, and ADH, formaldehyde dehydrogenase, formaldehyde oxidase, and the like are more preferable from the viewpoints of specificity and the like.

The yeast that can be used in the present invention is not particularly limited, and can be appropriately selected depending on the gas phase substance to be decomposed. For example, yeast of the genus Saccharomyces, yeast of Schizosaccharomyces Fungi, yeasts of the genus Candida, yeasts of the genus Pichia, yeasts of the genus Hansenula, yeasts of the genus Torulopsis, yeasts of the genus Acetobacter, etc. Is mentioned. Examples of the genus Saccharomyces include Saccharomyces cerevisiae, Saccharomyces bayanus, etc. Examples thereof include Candida utilis and Candida lipolytica. Further, as belonging to Saccharomyces cerevisiae, for example, alcohol yeast (wine yeast, brewer's yeast), brewer's yeast, baker's yeast, and sake yeast (Saccharomyces sake), etc. Can be mentioned. Among these, yeast of Saccharomyces genus is preferable, Saccharomyces cerevisiae is more preferable, and baker's yeast is more preferable among them because the ratio between the enzyme obtained by crushing yeast and the amount of coenzyme is good.

In the present invention, from the viewpoint of handleability, the yeast is dried to a degree of powder or granules (water content is usually 10% by mass or less, preferably 8% by mass or less). From the viewpoint of storage stability, it is preferable to use dry yeast (dry yeast).

As such dry yeast, commercially available ones can be used. For example, as dry yeast of baker's yeast (Saccharomyces cerevisiae), dry yeast manufactured by Oriental Yeast Co., Ltd., AB Mauli's dry yeast for bread, Examples thereof include dry yeast for refrigerated bread manufactured by Nippon Sugar Sugar Co., Ltd.

The enzyme activity value of the gas phase substance-degrading enzyme derived from yeast is preferably 1.00 μM / s or more, and more preferably 1.50 μM / s or more. The enzyme activity value is obtained from a measurement of ethanol degradation. It is preferable to use a gas phase substance-degrading enzyme having an enzyme activity value within the above range in order to obtain sufficient resolution. The measuring method of an enzyme activity value can be measured by the method as described in an Example.

The method for extracting the gas-phase substance-degrading enzyme from the yeast is not particularly limited, and it can be obtained by crushing the yeast and self-digesting, and then removing unnecessary substances such as cell walls by centrifugation. In the present invention, it is not necessary to isolate and purify the gas phase material-degrading enzyme, and it may be prepared as a mixed solution (yeast crushing extract) containing the gas phase material-degrading enzyme. The detail of the manufacturing method of a yeast crushing extract is mentioned later.

The content ratio of the gas phase material decomposing enzyme is preferably 0.0001 to 5% by mass and more preferably 0.001 to 0.5% by mass based on the total amount of the gas phase material decomposing substance of the present invention. preferable. If it is less than 0.0001% by mass, it may be difficult to sufficiently remove substances in the gas phase. If it exceeds 5% by mass, the proportion of enzymes not involved in the reaction increases, and the reaction rate per enzyme amount increases. There is a risk that efficiency will decrease from the viewpoint. The content of the gas phase substance-decomposing enzyme in the gas phase substance-decomposed product can be calculated from the enzyme activity value by the following procedure.

1) Prepare buffer solutions of purified enzymes of various concentrations (hereinafter referred to as purified enzyme solutions), measure the enzyme activity values of the purified enzyme solutions of each concentration, and create a calibration curve based on the enzyme concentrations and the measured enzyme activity values. create.
2) Measure the enzyme activity value (μM / s) of a solution containing a gas phase substance-degrading enzyme (for example, yeast disruption extract), and calculate the concentration of the solution containing the gas phase substance-decomposing enzyme from the calibration curve created above. To do.
3) The amount of the gas phase substance decomposing enzyme used in the gas phase substance decomposing body is calculated by multiplying the calculated concentration of the solution containing the gas phase substance decomposing enzyme by the amount using the solution.

Specifically, for example, when ADH is used as a gas phase substance-degrading enzyme, when the purified enzyme concentration is 0.5 mg / mL, 1 mg / mL, 1.5 mg / mL, 2 mg / mL, the enzyme activity value is , 0.61 μM / s, 1.45 μM / s, 2.35 μM / s, 3.11 μM / s, and therefore a calibration curve can be obtained based on the numerical values. From the calibration curve, the amount of ADH used (that is, the amount of ADH contained in the gas phase substance decomposition product) can be calculated.

(2) Coenzyme In the present invention, a coenzyme can be used together with a gas phase substance-degrading enzyme derived from yeast as necessary. The coenzyme is also preferably derived from yeast as in the case of the gas phase substance-degrading enzyme. For example, when the gas phase substance degrading enzyme is ADH or ALDH, oxidized nicotinamide adenine dinucleotide (NAD ⁺ ) is used, and when it is an aldehyde oxidase, reduced nicotinamide adenine dinucleotide (NADH) is used. be able to.

The content of the coenzyme is preferably 20% by mass or less, and more preferably 10% by mass or less, based on the total amount of the gas phase substance decomposition product of the present invention.

(3) Supporting substrate formed from PVA resin As PVA resin used in the present invention, for example, PVA resin obtained by saponifying polyvinyl acetate or a derivative thereof; vinyl acetate and vinyl acetate copolymerized Saponified products of copolymers with possible monomers; modified PVA resins obtained by acetalizing, urethanizing, etherifying, grafting, phosphoric esterifying, etc. of PVA resins; These PVA resins can be used alone or in combination of two or more. Among these, PVA resin is preferable from the viewpoint of good hygroscopicity.

Monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids such as (anhydrous) maleic acid, fumaric acid, crotonic acid, itaconic acid, (meth) acrylic acid and esters thereof; α such as ethylene and propylene -Olefin, (meth) allylsulfonic acid (soda), sulfonic acid soda (monoalkylmalate), disulfonic acid soda alkylmalate, N-methylolacrylamide, acrylamide alkylsulfonic acid alkali salt, N-vinylpyrrolidone, N-vinyl Examples include pyrrolidone derivatives. These monomers copolymerizable with vinyl acetate are preferably 10 mol% or less, more preferably 5 mol% or less in the PVA resin.

The average degree of polymerization of the PVA resin is preferably 100 to 3000, more preferably 500 to 2000, from the viewpoint of the decomposition efficiency of the gas phase substance. The average saponification degree of the PVA-based resin is preferably 85 to 100 mol%, more preferably 90 to 100 mol%, and further preferably 95 to 100 mol%. In the present invention, by appropriately controlling the type (composition), molecular weight, and saponification degree of the PVA-based resin within the above ranges, the above-mentioned effects can be improved, and the gas phase substance decomposition product and gas phase of the present invention can be improved. This is preferable because the durability of the phase material decomposition unit can be improved.

The content ratio of the PVA-based resin is preferably 30 to 98% by mass, more preferably 50 to 95% by mass, based on the total amount of the gas phase substance decomposition product of the present invention. If it exceeds 98% by mass, it may be difficult to exert high enzyme activity, and if it is less than 30% by mass, it may be difficult to maintain the enzyme activity over a long period of time.

(4) Water The vapor-phase material decomposition product of the present invention contains water. The content ratio of the water is preferably 1.9999 to 50% by mass, more preferably 5 to 35% by mass, based on the total amount of the gas phase substance decomposition product of the present invention. The water is preferably contained in such a proportion when the vapor-phase material decomposer of the present invention is used. If the water content is less than 1.9999% by mass, the efficiency of the enzyme reaction may be reduced. If the content is higher than 50% by mass, the enzyme may be easily deteriorated during long-term storage. The mechanical strength of the dismantling itself may be extremely reduced.

In the gas phase material decomposition product of the present invention, the preferable content ratio of water can be adjusted by utilizing the spontaneous hygroscopic property of the gas phase material decomposition product in the use environment. It is also possible to adjust the preferable amount of water by supplying water by a method of spraying an appropriate amount of water intermittently or continuously to the gas phase substance decomposer during use or during use.

In the gas phase material decomposition product according to the present invention, the adjustment of the preferable water content ratio is performed in the gas phase material decomposition product in addition to the method of directly utilizing the hygroscopic property inherent in the hydroxyl group in the PVA resin. It can also be performed by a method of containing an additive capable of adjusting the hygroscopicity.

Examples of the additive capable of adjusting the hygroscopic property that can be contained in the gas phase substance decomposition product of the present invention include at least one of saccharides, polyhydric alcohols, polyalkylene glycols, and amino acids. It is done. Specifically, for example, sugars such as glucose, sucrose, maltose, xylitol, trehalose, oligosaccharide, cellulose, carboxymethylcellulose, chondroitin sulfate; ethylene glycol, propylene glycol, butylene glycol, glycerin, diglycerin, polyglycerin, etc. Polyhydric alcohols; Polyalkylene glycols such as polyethylene glycol, polypropylene glycol, polybutylene glycol, polyethylene glycol-polypropylene glycol copolymer; and amino acids such as aspartic acid and arginine. Among these, in addition to imparting hygroscopicity, at least one of the saccharides specifically mentioned above can be preferably used in that it has an effect of inhibiting degradation of the enzyme. Moreover, it is preferable that these components are derived from yeast as well as the gas phase substance-degrading enzyme.

When the additive capable of adjusting the hygroscopicity is contained, the content is preferably 50% by mass or less, more preferably 1 to 50% by mass, based on the total amount of the gas phase substance decomposition product. More preferably, it is ˜20% by mass. When the content of the additive capable of adjusting the hygroscopicity is more than 50% by mass, the effect of the PVA resin may be impaired.

(5) Others The vapor phase material decomposition product of the present invention contains the PVA resin, the gas phase material decomposition enzyme, and water. Moreover, the said coenzyme and the additive which can adjust hygroscopicity can be added arbitrarily.

Furthermore, the gas phase material decomposition product of the present invention may contain other additives in addition to the above as long as the enzyme activity is not impaired. Examples of other additives include inorganic salts, organic salts, surfactants, preservatives, dyes, cross-linking agents, ultraviolet absorbers, primers for improving adhesion to the substrate, and the like. The content ratio of these other additives can be appropriately determined within a range that achieves the desired effect and does not impair the desired effect of the present invention. It is preferably 10% by mass or less, more preferably 5% by mass or less, and further preferably 3% by mass or less.

The form of the vapor phase substance decomposition product of the present invention is not particularly limited, but is a solidified form in which the PVA resin forms a supporting substrate and the enzyme is dispersed in the supporting substrate. Is preferred. The solidified form may be in the form of a gel as long as it does not have fluidity, but it is preferable to have a certain degree of hardness when considering the mechanical strength of the gas phase substance decomposition product. Further, the enzyme may be dispersed in an embedded state in the polymer, or may be partly exposed and dispersed.

Specific examples of the vapor-phase material decomposition product of the present invention include a sheet shape, a mesh shape, and a film shape, and among these, a film shape is preferable. The thickness is preferably from 0.01 to 5000 μm, more preferably from 0.1 to 100 μm. If the thickness is less than 0.01 μm, the ratio of the enzyme exposed to the outside rather than the inside of the film increases, and the stability of the enzyme may be reduced. If the thickness is greater than 5000 μm, the enzyme reacts with the enzyme. It is difficult to obtain sufficient contact between the phase substance and the enzyme, and the enzyme reactivity may be reduced.

The gas phase material decomposition product of the present invention has the above-mentioned effects by including a specific gas phase material decomposition enzyme, a PVA resin, and water. In particular, the gas phase material decomposition enzyme, PVA The effect of the present invention can be obtained even when the gas phase substance decomposed product is stored for a long period of time by controlling the content ratio of the resin and water in the above range, or by adding a specific additive. Is preferable because the effect of the present invention can be maintained for a long time.

Moreover, as described above, the gas phase material decomposition product of the present invention is formed from a mixed solution containing a PVA resin, a yeast-derived gas phase material decomposing enzyme, and water. It preferably contains yeast-derived gas-phase substance-degrading enzyme, yeast-derived coenzyme, water, etc., and mixes yeast disruption extract containing gas-phase substance-degrading enzyme obtained by crushing yeast described later and PVA resin solution It is preferable that it is obtained. The yeast crushing extract contains a yeast-derived gas phase material degrading enzyme, a yeast-derived coenzyme, and water.

(6) Method for Producing Gas Phase Material Decomposition Body The method for producing the gas phase material decomposition body of the present invention is not particularly limited. For example, PVA resin, yeast-derived gas phase material decomposition enzyme, and It can be manufactured by a manufacturing method including a step of coating a mixed solution containing water on a substrate to form a coating film, and a step of drying the coating film.

The mixed solution is preferably obtained by mixing a yeast disruption extract containing a gas phase substance-degrading enzyme obtained by disrupting yeast and a PVA resin solution. As described above, in the present invention, a gas phase material degradation product is produced by a very simple method of mixing a yeast disruption extract directly with a PVA resin solution without isolating the gas phase material degradation enzyme. It is something that can be done. Hereinafter, the method using the yeast disruption extract, which is a preferred embodiment of the present invention, will be specifically described.

A specific method for obtaining a yeast disruption extract containing a gas phase substance-degrading enzyme from yeast is as follows.
1) The yeast is dissolved in a predetermined amount of solvent to prepare a yeast solution. At this time, the concentration of the yeast solution is preferably 0.1 to 0.5 g / mL, and more preferably 0.15 to 0.3 g / mL. Examples of the solvent include water; various buffer solutions such as acetate buffer, phosphate buffer, Tris-HCl buffer, carbonate buffer, Good's buffer; ethanol, methanol, propanol, dimethyl sulfoxide, dimethylformamide, and the like. These organic solvents can be used alone or as a mixture. Depending on the type of enzyme, it may react with alcohol, and among these, water or a buffer solution in which the enzyme does not cause irreversible denaturation is preferable. The pH of the buffer solution is preferably pH 6.0 to 9.0, and more preferably pH 8.
2) The yeast solution is put into a bead-type cell crusher to crush the yeast. At this time, glass beads having an appropriate shape and amount are used. The crushing conditions can be determined as appropriate, but the acceleration is usually about 1 to 10 m / s, and the crushing can be performed under any number of times (for example, about 1 to 5 times of treatment for about 10 to 120 seconds at a time). . The temperature at the time of crushing is not particularly limited, but is preferably 45 ° C. or less, more preferably 40 ° C. or less, further preferably 30 ° C. or less, and particularly preferably 15 ° C. or less. preferable. Moreover, you may crush, cooling, as needed. Usually, the enzyme begins to be inactivated at 30 ° C. and completely inactivated at 50 ° C., but the enzyme contained in the yeast crushed extract used in the present invention is not inactivated even at 40 ° C. and has high heat resistance. Is.
3) The obtained crushed liquid is centrifuged using a refrigerated centrifuge, and the supernatant is collected to obtain a yeast crushed extract. The conditions of the cooling centrifuge can be adjusted as appropriate, but are usually 1 to 10 ° C., 500 to 10,000 rpm, and about 1 to 10 minutes.

As the PVA-based resin, those described above can be preferably used. Examples of the solvent used for the PVA resin solution include water; various buffer solutions such as acetate buffer, phosphate buffer, Tris-HCl buffer, carbonate buffer, Good's buffer; ethanol, methanol, A single solution or a mixture of various organic solvents such as propanol, dimethyl sulfoxide, dimethylformamide and the like can be used. Among these, water or a buffer solution is preferable.

The concentration of the PVA resin solution is not particularly limited, but is preferably 1 to 15% by mass, and more preferably 5 to 10% by mass.

The mixing ratio of the yeast crushed extract and the PVA resin solution is not particularly limited. For example, the yeast crushed extract: PVA resin solution = 0.5: 9.5 to 4: 6 (mass) Ratio), preferably 1: 9 to 2: 8 (mass ratio).

In addition to the PVA resin solution and the yeast crushing extract, the various additives can be mixed in the mixed solution as necessary. Moreover, various additives can be added to a liquid mixture so that the compounding quantity in a gaseous-phase material decomposition body may become in the said range.

In addition, the coating and drying may be performed by applying the mixed solution to a substrate to form a coating film, and evaporating (drying) the solvent from the coating film to form a film or the like. Examples thereof include a continuous coating method in which a certain amount of the mixed solution is applied while being slid and the solvent is dried, and a method in which the mixed solution is sprayed onto a suitable substrate and dried.

The concentration of the PVA-based resin in the mixed solution containing the PVA-based resin and the enzyme used when producing the gas-phase material decomposed material of the present invention is such a concentration that the gas-phase material decomposed material can be easily prepared into a film, for example Usually, it is in the range of 0.1 to 50% by mass. If the polymer concentration is less than 0.1% by mass, the production efficiency may decrease. If the polymer concentration exceeds 50% by mass, the viscosity of the mixed solution increases and the handling property at the time of forming a gas phase substance decomposition product may decrease. Occurs.

In producing the vapor phase substance decomposed body of the present invention, the material of the substrate for applying the mixed liquid includes metals, ceramics, wood, plastic, glass, paper, etc. Examples thereof include a plate, a substrate having a curved surface, a fiber, a nonwoven fabric, and a porous body.

In the production of the gas phase substance decomposition product of the present invention, the drying step of the coating film can be performed while suppressing degradation of the enzyme because it contains the PVA resin, but the enzyme is the most in the production process. Since it is a process that easily deteriorates, it is preferable to perform it carefully. Specifically, it is usually dried in the range of 10 to 70 ° C., desirably in the range of 20 to 50 ° C. If the drying temperature is less than 10 ° C., the drying efficiency may be lowered, and if it is higher than 70 ° C., the enzyme deterioration suppressing effect by the polymer is lowered, and the enzyme may be deteriorated.

The vapor-phase material decomposition product of the present invention formed on the substrate can be used as it is as a vapor-phase material decomposition unit of the present invention, which will be described later. In some cases, it can be peeled off from the substrate and used as a self-supporting film.

2. Gas Phase Material Decomposition Unit The gas phase material decomposition unit of the present invention is a unit in which the above-described gas phase material decomposition product of the present invention is provided on a substrate so as to be in contact with a gas phase such as air. Examples of the substrate include the above-described substrates, and further, building materials, furniture, clothing, air-conditioning equipment, air filters, refrigerators, automobiles, and the like including such a substrate.

3. Gas Phase Purification Method The gas phase purification method of the present invention is characterized in that the gas phase material decomposition unit of the present invention is brought into contact with a gas phase such as air.

Examples of the method for bringing the gas phase material decomposition unit into contact with the gas phase include a method in which the gas phase material decomposition product of the gas phase material decomposition unit is exposed to the gas phase to be purified. In the case of a gas phase material decomposition unit in which a gas phase material decomposition product is formed in a minute space, a flow of the gas phase to be purified is made with a fan or the like so as to contact the gas phase material decomposition product in the minute space. Can be brought into contact with each other by a method of feeding a gas phase to the substrate.

In the gas phase purification method of the present invention, a substance in the gas phase capable of reacting with the enzyme is adsorbed on the surface of the gas phase substance decomposition body of the gas phase substance decomposition unit, and bound to the enzyme present on the surface, or The substance adsorbed to the enzyme in the gas phase substance decomposition product moves and binds, and the enzyme reaction proceeds to decompose and purify the substance.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples and comparative examples.

Preparation Example 1 Preparation of PVA solution PVA (trade name: JF-17, degree of polymerization: 1700, degree of saponification: 98-99%, Nippon Vinegar Poval (stock) in 10 mL of 50 mM NaH ₂ PO ₄ buffer (pH 8.0) )) Was dissolved to prepare a PVA solution (5% by mass). The obtained PVA solution was used as a supporting field in Examples and Comparative Examples.

Example 1
1. Preparation of yeast crushed extract 12.5 g of dry yeast (trade name: Oriental yeast / general use, Saccharomyces cerevisiae, manufactured by Oriental Yeast Co., Ltd.) was dissolved in 50 mL of 50 mM NaH ₂ PO ₄ buffer (pH 8.0), φ1 A 15 mL centrifuge tube (Falcon) was packed together with 4.0 g of 0.0 mm glass beads (Fuji Science Industry Co., Ltd.). This was crushed using a bead type cell crusher (Fast prep 24, manufactured by MP-Biomedicals) under the conditions of acceleration 6.0 m / s, 30 s × 2 while cooling with ice. This crushed liquid was centrifuged under conditions of 5 ° C., 4000 rpm, and 5 minutes with a cooling centrifuge (manufactured by Tommy Seiko Co., Ltd.), and the supernatant was collected to obtain a yeast crushed extract. In addition, the yeast crush extract contained alcohol dehydrogenase (ADH) as an enzyme and oxidized nicotinamide adenine dinucleotide (NAD ⁺ ) as a coenzyme. About the obtained yeast crushing extract, the enzyme activity value was measured by the following method and found to be 1.1 μM / s.

<Method for measuring enzyme activity value>
1) An optical cell having an optical path length of 1 cm was charged with 250 μL of NAD ⁺ solution (10 mM). Furthermore, 1200 μL of 50 mM NaH ₂ PO ₄ buffer (pH 8.0) and 600 μL of 1.5 M ethanol were charged and stirred. The optical cell was set in a spectrophotometer (equipment trade name, etc .: UV-2550, manufactured by Shimadzu Corporation), and 20 μL of yeast disruption extract obtained in Examples 1 to 3 and 50 mM NaH ₂ PO ₄ buffer were used. (PH 8.0) 600 μL was quickly added.
2) Absorbance at 340 nm (NADH) was measured over time. A graph plotting the concentration of 340 nm (NADH) every hour was created from the measured change in absorbance and the following formula. The enzyme activity value (unit: μM / s, enzyme concentration per unit time) was calculated from the slope of the initial graph from the start of measurement to 10 seconds.
In the above calculation, the slope of the initial graph is that the enzyme (ADH) contained in the yeast disruption extract causes the following reaction to convert alcohol to aldehyde, which is a reversible reaction. Therefore, the enzyme activity value is calculated from the slope of the graph at the initial stage of measurement without considering the reverse reaction.

(Analysis method)

ΔA ₃₄₀ / min: absorbance change per minute at 340 nm D: enzyme dilution rate (1)
V: Final liquid volume (2.67 mL)
ε: mmol molecular absorption coefficient of NADH at 340 nm (6.3 L · mmol ⁻¹ · cm ⁻¹ )
d: Optical path length (1 cm)
v: Enzyme solution amount (0.02 mL)

2. Production of Film 0.7 mL of the yeast crushed extract obtained above was added to 3.3 mL of a 5% by mass PVA solution. After dropping this onto a petri dish having an outer diameter of 91 mm × height of 20 mm, the sheet is dried overnight (about 12 hours) at room temperature (23 ° C.) until the moisture content of the sheet reaches about 20%. A sheet sample of ˜50 μm was prepared. The total weight of the sheet sample was 250 mg.

The PVA resin contained in the obtained sheet sample is 165 mg (use 3.3 mL of 5 mass% PVA solution). Further, as described above, the enzyme activity is 1.1 μM / s, and the effective enzyme amount concentration calculated therefrom is 0.80 mg / mL. Since the used yeast crush extract amount is 0.7 mL, the amount of effective enzyme contained in the obtained sheet sample is 0.56 mg.

Example 2
In the same manner as in Example 1 except that dry yeast for bread (trade name: Active Dry Yeast (ADY), Saccharomyces cerevisiae) manufactured by AB Mauli was used instead of the dry yeast used in Example 1. Was made. The total weight of the sheet sample was 250 mg.

The yeast crushing extract of Example 2 contains alcohol dehydrogenase (ADH) as an enzyme and oxidized nicotinamide adenine dinucleotide (NAD ⁺ ) as a coenzyme, and the enzyme activity value is 1.9 μM / s.

The PVA resin contained in the obtained sheet sample is 165 mg (use 3.3 mL of 5 mass% PVA solution). Further, as described above, the enzyme activity is 1.9 μM / s, and the effective enzyme amount concentration calculated therefrom is 1.28 mg / mL. Since the used yeast crushing extract amount is 0.7 mL, the amount of effective enzyme contained in the obtained sheet sample is 0.90 mg.

Example 3
Instead of the dry yeast used in Example 1, it was the same as Example 1 except that dry yeast for refrigerated bread (trade name: Nitten FR yeast dry yeast product, Saccharomyces cerevisiae) manufactured by Nippon Sugar Sugar Co., Ltd. was used. Thus, a sheet sample was produced. The total weight of the sheet sample was 250 mg.

The yeast crushing extract of Example 3 contains alcohol dehydrogenase (ADH) as an enzyme and oxidized nicotinamide adenine dinucleotide (NAD ⁺ ) as a coenzyme, and the enzyme activity value is 1.7 μM / s.

The PVA resin contained in the obtained sheet sample is 165 mg (use 3.3 mL of 5 mass% PVA solution). Moreover, as above-mentioned, enzyme activity is 1.7 micromol / s and the effective enzyme amount density | concentration calculated from there is 1.13 mg / mL. Since the used yeast crush extract amount is 0.7 mL, the amount of effective enzyme contained in the obtained sheet sample is 0.79 mg.

Comparative Example 1
0.7 mL of 50 mM NaH ₂ PO ₄ buffer (pH 8.0) was added to 3.3 mL of a 5% by mass PVA solution, which was dropped into a petri dish having an outer diameter of 91 mm × height of 20 mm, and then overnight (about 12 hours) A sheet sample having a thickness of 10 to 50 μm was prepared by drying at room temperature (23 ° C.).

The following evaluation was performed using the sheet samples obtained in Examples and Comparative Examples.

<Formaldehyde gas decomposition experiment>
The sheet samples obtained in Examples 1 to 3 and Comparative Example 1 were placed together with the petri dish at the bottom of a 6 L side-mouth cock screw desiccator, and a 50 mL beaker heated to 200 ° C. was placed on the inner lid and the desiccator The lid was closed. 10 μL of an aldehyde solution (a 0.108% solution prepared by thermally decomposing paraformaldehyde) is dropped from the upper screw mouth, and the interior is kept at a constant formaldehyde concentration (initial concentration: 3.3 to 3) by quickly closing the lid. 0.5 ppm). The initial formaldehyde concentration was measured with a detector tube (for 91-L, 91-LL formaldehyde, manufactured by Gastec Co., Ltd.) at an initial stage and after lapse of time. The result is shown in FIG.

<Heat resistance test>
Enzyme activity after storing the purified enzyme solution (1 mg / mL) and the yeast crush extract obtained in Example 2 at each temperature (5, 20, 30, 40, 50, 60, 70 ° C.) for 12 hours The value was measured. The enzyme activity maintenance rate (%) after storage was calculated with the enzyme activity value before storage as 100%. The result is shown in FIG.

From FIG. 1, it was confirmed that in Examples 1 to 3, the formaldehyde concentration in the system significantly decreased after 120 hours. On the other hand, in Comparative Example 1, although it decreased at the initial stage, the decrease was due to the decrease in the system concentration due to the adsorption of formaldehyde on the film, and the constant concentration was maintained after a certain period of time. Therefore, clear resolution of formaldehyde was confirmed by including a gas phase substance decomposing enzyme and a PVA resin.

Further, from FIG. 2, it was confirmed that the yeast crushing extract has a heat resistance higher by about 10 ° C. than the purified enzyme.

To provide a sheet having decomposition performance at a very low price by using the gas phase material decomposition product of the present invention containing a specific gas phase material decomposition enzyme, PVA resin and water as a harmful gas decomposition sheet. Is possible. It is considered that the harmful gas decomposition sheet of the present invention, which is highly functional but inexpensive, is highly likely to be accepted not only in developed countries but also in emerging markets that have problems such as sick houses as a current problem.

Claims

A gas phase substance decomposition product formed from a mixed solution containing a polyvinyl alcohol-based resin, a yeast-derived gas phase substance decomposing enzyme, and water.
2. The vapor phase substance decomposition product according to claim 1, wherein the polyvinyl alcohol-based resin forms a supporting base material, and the yeast-derived gas phase substance decomposing enzyme is dispersed in the supporting base material.
The gas phase substance decomposition product according to claim 1 or 2, wherein the degree of polymerization of the polyvinyl alcohol resin is 100 to 3000.
4. The vapor phase substance decomposition product according to claim 1, wherein the degree of saponification of the polyvinyl alcohol-based resin is 85 to 100 mol%.
The gas phase according to any one of claims 1 to 4, wherein a content ratio of the gas phase material decomposing enzyme is 0.0001 to 5% by mass based on the total amount of the gas phase material decomposing material. Substance decomposition product.
6. The vapor phase substance decomposition product according to claim 1, wherein the gas phase material decomposition product is in a sheet shape.
The gas phase material degrading enzyme according to any one of claims 1 to 6, wherein the yeast-derived gas phase material decomposing enzyme is obtained by crushing yeast.
A vapor phase material decomposition unit comprising the vapor phase material decomposition product according to any one of claims 1 to 7 on a substrate so as to be in contact with the gas phase.
A gas phase purification method comprising contacting the gas phase substance decomposition unit according to claim 8 with a gas phase.
A step of forming a coating film by applying a mixed solution containing a polyvinyl alcohol-based resin, a yeast-derived gas phase substance-degrading enzyme, and water on a substrate;
And a step of drying the coating film.
The gas phase according to claim 10, wherein the mixed solution is obtained by mixing a yeast crushing extract containing a gas phase substance-degrading enzyme obtained by crushing yeast and a polyvinyl alcohol resin solution. A method for producing a substance decomposition product.