JPS6283887A - Carrier for immobilizing microorganism - Google Patents

Abstract

PURPOSE:The titled carrier, having open cells, consisting of a carbonaceous three-dimensional structure having skeleton reinforced with an organic material, having good reaction efficiency and improved heat and chemical resistance and mechanical strength, freely working the shape and nontoxic to the human body. CONSTITUTION:A carrier for immobilizing a microorganism, obtained by permeating a liquid composition consisting of an organic liquid material and inorganic material through a resin foam having open cells, curing the formed composite material, firing the cured composite material in an inert gas atmosphere to give a carbonacous three-dimensional structure having open cells, impregnating the structure with an organic material carbonizable into a three-dimensional structure, heating the impregnated structure at >=450 deg.C in a nonoxidizing atmosphere and carbonizing and reinforcing the skeleton and having 1-500mu open cell diameter and >=30% porosity.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a carrier for immobilizing microorganisms.

(Prior art) Conventional methods for immobilizing microorganisms include enveloping them in a fine lattice such as polymer gel (lattice type), or covering them with a semipermeable polymer film (microorganism). There is a capsule type) method, and carriers used in these methods include polymers such as polyacrylamide gel, polyvinyl alcohol, photocurable resin, starch, gelatin, and alginic acid, and carriers such as ethyl cellulose and polystyrene (hereinafter simply referred to as a On the other hand, there were
Another method for immobilizing microorganisms is to physically adsorb and immobilize microorganisms onto an inorganic carrier. The materials used for this purpose include porous glass, ceramics, metal oxides, activated carbon, etc. (hereinafter simply referred to as non-aS).
There was a carrier.

(Problems to be Solved by the Invention) Various conventionally used carriers have the following problems.

That is, in the case of an organic carrier, since the Wk organisms are wrapped in the carrier, the mass transfer efficiency is low, and the reaction efficiency by microorganisms is poor. Furthermore, since the organic carrier is made of organic matter, it cannot be subjected to high temperature sterilization treatment.

Furthermore, organic carriers have no resistance to chemicals such as organic solvents, acids, and alkalis, are easily decomposed by microorganisms, and cannot be recycled. Furthermore, the organic carrier is
Mechanical strength is relatively low.

The carrier itself easily falls off and has poor durability, and it is difficult to freely process the shape, making it extremely difficult to arbitrarily produce a three-dimensional structure having continuous pores. Somehow there was a problem.

On the other hand, with inorganic carriers, microorganisms etc. can come into direct contact with the substrate, so the mass transfer efficiency is higher than with organic carriers.
Advantages include high reaction efficiency by microorganisms, inorganic carriers can be treated at high temperatures, are resistant to chemicals such as organic solvents, acids, and alkalis, are not decomposed by microorganisms, and can be recycled. There is. However, on the other hand, with inorganic carriers, microorganisms are bound to the carrier by physical adsorption, and the retention of the microorganisms is poor.
In addition, when biological carriers are used as carriers for producing pharmaceuticals or foods, it is harmful to the human body if these fi biological carriers are mixed into the product.For example, Porous metals have the risk of ionizing, dissolving, and contaminating products, so they are currently not used much by professionals. Among these inorganic carriers, activated carbon is made of carbonaceous material, so it has an affinity for microorganisms and can increase its bonding ability to some extent. Since the activated carbon is activated carbon, its strength is extremely weak and brittle, so when it is used as a carrier, it may easily fall off, making it impossible to use a carrier made of activated carbon for a long period of time.
It is extremely difficult to process activated carbon into a desired shape due to its weak mechanical strength. The purpose of this invention, which had some problems, was to have a crystalline reaction efficiency using microorganisms, be able to be processed at high temperatures, be resistant to chemicals such as organic solvents, acids, and alkalis, and be able to be regenerated without being decomposed by microorganisms. Provides a carrier for immobilizing microorganisms that can be used, has relatively high mechanical strength, is durable to prevent falling off, and can be freely processed into a shape. It's about doing. A further object of the present invention is to provide a carrier for immobilizing microorganisms that has a high affinity for microorganisms, is harmless to the human body, and is suitable as a carrier for producing pharmaceuticals and foods.

(Means and effects for solving the problems) In view of the above-mentioned problems, the present inventor has conducted intensive delta research and has developed a carrier for immobilizing microorganisms that can completely solve these problems. succeeded in.

That is, the present invention is a carrier for immobilizing microorganisms, which is made of a carbonaceous three-dimensional structure having continuous pores and a reinforced skeleton.

The eight components of the carrier for immobilizing microorganisms of the present invention will be explained in detail below.

The carrier of the present invention is characterized in that it has continuous pores, that its skeleton is reinforced with carbonaceous material, and that it forms a three-dimensional carbonaceous structure.

First of all, a three-dimensional structure refers to a three-dimensional structure.
For example, this method utilizes the voids between the particle phases 91 where carbonaceous or carbonized grains t and particles are bonded to each other at their surfaces or points of contact, or the voids between the carbon fibers 1a. There are also methods that utilize the voids created by foaming the resin.

Continuous pores refer to pores through which the substrate passes, and include continuous pores formed by dot adhesion of particles or carbon taIia, or continuous pores formed by foaming reaction of carbonized resin, etc. be. The diameter of the continuous pores is 1 to 50
A range for 0 is preferred. If it is less than 500μ, the pores will be too small and it will be difficult for microorganisms to enter the pores.
Otherwise, the pores will be too large and microorganisms will easily fall out.

However, depending on the type of microorganisms to be immobilized, and if they form a colony, the size of the pore size should be determined by taking into account the size of the colony.
It is preferable to adjust within the range of o and t.

The ratio of pores to the surface area of the carrier (porosity) is
Considering the amount of microorganisms immobilized on the body and the reactivity of the microorganisms, it is generally preferable that the amount is 30% or more. This is because if it is less than 30%, the reaction efficiency by microorganisms will be significantly reduced.

However, this value is not limited to this, and it is preferable to select an optimal value depending on the type of microorganism and the structure of the carrier.

Conventionally, method 17 has been used as a manufacturing method for the above-mentioned carbonaceous three-dimensional structure, but which method can be used if a carbonaceous three-dimensional structure having continuous pores can be manufactured? May be used.

In the past, as disclosed in Japanese Patent Application Laid-Open No. 59-64511, particles filled with a predetermined size are heated at an appropriate temperature, and at the point where the surfaces touch each other, W
It is also possible to use a method in which a carbonaceous three-dimensional structure is obtained by adhering to a material, making it infusible or hardening, and then firing and carbonizing it without damaging its shape.

On the other hand, as another method for manufacturing a carbonaceous three-dimensional structure, as described in JP-A No. 59-350i1, carbon fibers are coated with a binder resin and the dried mass is pulverized to form particles. A predetermined Of-soluble particulate material was added to and mixed with the particles, this mixture was press-molded, hardened, and the soluble particulate material was eluted. A method of manufacturing the body may also be used.

Yet another method, as described in JP-A-59-146917, is to create a composite in which a resin foam having continuous pores is impregnated with a liquid composition consisting of an organic liquid substance and an inorganic substance. A method of obtaining a carbonaceous three-dimensional structure having continuous pores by firing in an active gas atmosphere after curing may be used.

Furthermore, as a method of 37+1, as described in Japanese Patent Publication No. 59-4171, a porous spherical crosslinked polymer is heat treated at a temperature of 200 to 350°C in an oxidizing atmosphere,
Then, a method of carbonization at a temperature of 400 to 12 oo'c in a non-oxidizing atmosphere may be used.

Next, the microorganism immobilization carrier according to the present invention.

It is necessary to strengthen the skeleton of a three-dimensional structure produced by the method described above, for example, by impregnating an organic substance that can be carbonized and carbonizing it. The reason for impregnating the skeleton of a three-dimensional structure with an organic substance to be carbonized and then firing and carbonizing it is to increase the mechanical strength of the carrier, prevent the carrier itself from falling off, and make it easier to process the carrier into a LI shape. It is. When the organic substance is thermoplastic as described in (h), the impregnated three-dimensional structure needs to be subjected to an infusibility treatment.

Infusibility treatment is a treatment that prevents the right a￥＠ from melting again, softening, and becoming fluidized. There are methods of making it infusible by wet oxidation, such as dissolving oxidizing acids and their salts in water. Note that when the skeleton of the three-dimensional structure is impregnated with a thermosetting resin, no infusibility treatment is necessary. Note that the method of infusibility treatment is not limited to this method, and any conventional method may be used.7 Next, the three-dimensional structure is fired and carbonized by heating. Note that carbonization is performed by firing. The method may be any conventional method; for example, the carbonization is carried out at a heating temperature of 450 DEG C. or higher in a non-oxidizing atmosphere. At this time, the carbonization yield tends to increase as the temperature increase rate decreases, but it is preferable to select the optimum temperature increase rate depending on the type of substance to be carbonized.

As described above, three-dimensional structures with various shapes and pore sizes can be obtained by various methods, but when forming a colony of microorganisms, the pore size should be selected appropriately depending on the size of the colony. Regarding the shape, it is preferable that the carrier is shaped into granules, plates, pipes, blocks, etc., depending on the use of the carrier.

Since the carrier for immobilizing microorganisms of the present invention is carbonaceous, oxygen-containing surface functional groups can be easily introduced through an oxidation reaction. Further, this oxygen-containing surface functional group can be substituted with another functional group 1, such as a methyl group, an amino group, a nitro group, etc., by an organic chemical method. Therefore, by covalently bonding the functional group of the carrier and the functional group of the microorganism, it is also possible to directly bond and immobilize the microorganism and the carrier. Since the carrier for immobilizing microorganisms of the present invention is carbonaceous, it has conductivity and can generate heat or form an electric field by means of an electric current.

In this case, if an alternating electric field is formed, microorganisms can be concentrated by dielectrophoresis or electrostatically collected on a carrier, which is an electrode.

(Effects of the Invention) As detailed above, the present invention has a microorganism immobilization carrier made of a carbonaceous three-dimensional structure with 11 pores and a reinforced skeleton. The carrier has good reaction efficiency with microorganisms.

Furthermore, since the carrier is made of carbonaceous material, it can be sterilized at high temperatures, has resistance to chemicals such as organic solvents, acids, and alkalis, is not decomposed by microorganisms, and can be recycled.

In addition, since this carrier is reinforced by the skeleton or organic material that forms the three-dimensional structure, its mechanical strength increases and it is possible to prevent the carrier itself from falling off, making it durable. You can freely process the shape.

On the other hand, since this carrier is made of carbonaceous material, it can be expected that it will show a high affinity for microorganisms, and thus f
7. It is possible to obtain good connectivity. Furthermore, this carrier is completely harmless to the human body even when used as a carrier for producing pharmaceuticals or foods. Furthermore, as illustrated, the carrier of the present invention is a tertiary carrier having optimal continuous pores, depending on the type of microorganisms to be immobilized, and in the case where they form a colony, taking into account the size of the colony. The original structure can be obtained by selectively utilizing various manufacturing methods.

Claims (3)

[Claims] (1) A microorganism immobilization carrier consisting of a carbonaceous three-dimensional structure with continuous pores and a reinforced skeleton. (2) The carrier for immobilizing microorganisms according to claim 1, wherein the skeleton is reinforced by carbonized organic matter. (3) The carrier for immobilizing microorganisms according to claim 1, wherein the continuous pore diameter is 1 to 500μ.