JPS6047673A - Carrier particle - Google Patents

Abstract

PURPOSE:To provide a carrier particle producible continuously at a low cost, capable of immobilizing microorganisms in high concentration, and useful for the stable bioreaction such as fermentation and water-treatment, etc., by winding a yarn or fiber around a plastic substrate having notches at the outer surface. CONSTITUTION:A yarn or fiber (natural or synthetic fiber, preferably a tape or sheet woven by filament of 0.1- several tens mu diameter or a yarn having a thickness of several tens - several hundreds mu in view of tensile strength) is wound around a plastic substrate having notches at the outer surface (a thermoplastic resin or thermosetting resin such as PE, PS, polyurethane, etc. preferably having a length and diameter of 1-50mm.), to obtain the objective carrier. It can immobilize microorganisms, etc. in high concentration. Although excess microorganisms are sometimes released from the gap between the yarns and fibers according to the progress of proliferation, and dissipated from the system by the flow and vigorous agitation of the carrier particles, however, the microorganisms retained in the inside of the carrier are resistant to the release. Accordingly, the carrier is suitable to use in the form of fluidized bed or mixed bed, etc.

Description

[Detailed Description of the Invention] The present invention provides a method for maintaining microorganisms and enzymes (hereinafter simply referred to as "microorganisms, etc.") at a high concentration in a biological reaction device (bioreactor) used for fermentation production, water treatment, etc. It relates to carrier particles that can

Recently, a method of immobilizing microorganisms and the like in a bioreactor and performing continuous reactions has come to be widely adopted. Various proposals have been made not only for methods of immobilizing microorganisms, but also for immobilization carriers.

In order to operate a bioreactor efficiently and stably, the carrier used to immobilize microorganisms plays an extremely important role. The important things about this carrier are: 1) It can immobilize microorganisms at a high concentration, 2) The immobilized microorganisms can participate in the reaction to the maximum extent, and 2) It can maintain the activity of microorganisms during continuous operation. .

An object of the present invention is to provide carrier particles that satisfy the above requirements. That is, the present invention relates to carrier particles formed by winding threads or fibers around a synthetic resin base material having notches on the outer surface.

When carrier particles with microorganisms etc. attached to the surface are used in a biological reaction device, a fixed bed is used.

There are fluidized beds, mixed beds, etc., but in either case, microorganisms, etc. tend to adhere to the carrier surface, and even if the excess microorganisms, etc. that adhere to it due to proliferation etc. are peeled off, the necessary microbial film thickness will still be required. It is important that this is maintained at all times.

The synthetic resin used for producing the carrier particles of the present invention is not particularly limited and may be any thermoplastic resin, such as polyethylene, polyglopylene, polystyrene, AES resin, polyurethane, polyvinyl chloride resin, methylpentene polymer, etc. There is.

The shape of the synthetic resin base material is arbitrary, but it is preferably rod-shaped, cylindrical, or cylindrical, and has a notch as described below on its outer surface, and its dimensions are small in terms of specific surface area. However, it is limited from the viewpoint of manufacturing technology, and generally both length and diameter are 1 to 50 mm, preferably 2 to 10 mm. , is appropriate. Furthermore, although it is necessary for the synthetic resin base material to have a notch on the outer surface, the structure of the notch is arbitrary, and may be a continuous notch, -1: or an intermittent notch. For example, those having the cross-sectional shapes shown in Figures a-f are actual examples of t and m. Other examples of base materials having such notches include those with intermittent linear single-point notches, and those with roughening treatments such as scratches to provide the notches. There are things etc. Furthermore, 2! as shown in FIG. 1 a-f! Substrates of the present invention also include substrates in which the surface of li:4j has been subjected to roughening such as scratches by mechanical means.

Next, the threads or fibers may be either natural or synthetic, but in the case of fibers, they are woven from threads of 0.1 micron to several tens of microns, preferably in the form of a tape or sheet. In the case of yarn, tens to hundreds of microns or more is appropriate from the viewpoint of tensile strength. In the case of thread, the maximum thickness is suitably 115 or less of the length of the carrier particles, and the preferred length and diameter of the carrier particles are both 2 to 1.
Since it is 0 mm, the preferable maximum thickness is 2πm. If the thickness is less than the lower limit, it will be difficult for microorganisms and the like to enter the inside if it is cut when being wrapped around the base material or if it is tightly wrapped. Also, if the thickness exceeds the upper limit,
There is a drawback that double winding occurs during particle production, resulting in large fluctuations in the specific gravity of the particles.

The above yarns or fibers also include carbon fibers. Further, the material of the thread or fiber may be the same as or different from that of the synthetic resin base material.

It is preferable to wind threads or fibers around the base material by mechanical means, and the winding should be done at a pitch that allows microorganisms, enzymes, etc. to enter and exfiltrate, and the amount of winding should be The decision should be made taking into consideration the purpose of use.In addition, the wound yarn or fiber can be fixed to the left hand using an adhesive, or it can be spot welded to the base material by heating. The adhered elongated base material is cooled if necessary and then cut into appropriate dimensions to obtain the carrier particles of the present invention. Figure M2 is a sketch showing one example of this, in which a synthetic resin such as polyethylene is After heating to 150℃,
) to a = 2 myi-b = i, s min
The cross-shaped synthetic resin obtained by extrusion from the cross-shaped nozzle of
l! Synthetic fibers, such as polyester fibers several microns in thickness, are wound spirally around the fabric. At this time, spot welding is performed by applying heat of 150 to 180'C to the contact portion between the two. The base material with the fibers wound thereon is cooled during this time by passing through a water tank where tap water at room temperature is stored, and then enters a part of the cutter where it is cut into a length of 5 TL and carrier particles are continuously produced. be done.

In order to adjust the specific gravity of the carrier particles of the present invention, traps can be prepared by mixing an appropriate amount of inorganic or organic filler (for example, calcium carbonate, clay, talc, etc.) into the base material to increase the specific gravity, or by using a blowing agent. Means such as foaming the synthetic resin to lower the specific gravity can be adopted as appropriate. Moreover, the addition of these fillers and foaming promote roughening and hydrophilicity of the surface of the base material, which can help improve the initial microbial adhesion performance.

Microorganisms and r! ? : The trap for attaching elements, etc. can be carried out by a conventional method. For example, in the case of microorganisms, the carrier particles are placed in a biological reaction device or other container together with the microorganisms and nutrients suitable for the growth of the microorganisms. -5 Kill the microorganisms. In addition, in the case of specific microorganisms such as yeast, the left-handed notch 7
In some cases, it may be possible to adopt a method in which the thread or fiber is wound after the fiber is introduced into the fiber. On the other hand, in order to make the enzyme adhere to the carrier particles by +1, there is a method in which an enzyme solution is placed in a suitable container and the carrier is immersed in this solution.In this case, adhesion is improved by adding an adhesive substance, etc. can do.

When the carrier particles of the present invention carrying microorganisms, etc. are used in a biological reaction device, in a steady state, as shown in Figure 3a, a large amount of microorganisms is deposited on the surface of the base material, the surface of threads or fibers, and even on the intermediate part thereof. It is observed that the following substances are attached and retained. In addition, surplus microorganisms accompanying proliferation may come out from the gaps between the threads and fibers.

If the carrier particles to which such microorganisms are attached are fluidized or mixed vigorously, excess microorganisms will be detached, but
What is held inside has extremely strong adhesion to the carrier particles and does not peel off even under such conditions. Therefore, by using the carrier particles of the present invention, biological reactions such as fermentation production and water treatment can be carried out stably.
It is especially suitable for use in fluidized beds, mixed beds, etc.

Further, when used as a fixed bed, cleaning may be carried out when the clogging becomes significant. In addition, the carrier particles of the present invention have the advantage that they can be manufactured continuously and at low cost.

Next, the present invention will be explained in detail with reference to examples.

Example 1 In order to study the relationship between the structure of carrier particles and microbial-adhered dust, glutamic acid fermentation was carried out at ℃ using the following three types of carrier particles to which glutamic acid producing bacteria were attached.

As a carrier particle ■ Made of polypropylene, it has a cylindrical cross section with a length of 5 mm and a diameter of 5 mm, and a smooth surface with a specific gravity of 0.9.
0 (carrier particles)), (1) Made of polypropylene, foam molded (-5 length).

It has a cylindrical cross section with a diameter of 5 dragons, and a rough surface.Specific gravity of 0.8.
1 (carrier particles 2) and 2) carrier particles 2 are provided with notches so that the cross-sectional shape is cross-shaped as shown in FIG.
No. 82 (carrier particles 3) was used.

As experimental equipment for glutamic acid fermentation, we used three glass-made vessels with a diameter of 15 mm, a height of 30 cm and 111 degrees, and an effective reaction volume of approximately 41 as shown in Figure 4, each of which was filled with 21 of each of the three types of carrier particles mentioned above. The experiment was conducted in a downward flow fluidized bed. In addition, during the experiment, all experimental equipment, culture medium supply lines, etc. were sterilized.

1,50% of a medium containing 3% by weight of glucose as a carbon source
It was introduced into the distributor 4 in the experimental apparatus 3 from the supply line 1 by the pump 2 at a rate of rILl/hr. In addition, each experimental device was equipped with Corynebacterium glutamicum (Oorinebacterium glutamicum).
500 ml of tumor fluid containing about 0.5% ATCC13032 was added. Aerobic reaction trap Necessary oxygen was dissolved in the culture medium in the draft tube 6 by supplying air from the air supply pipe 7. The culture medium was circulated through the draft tube 6 and the reaction section where the phase particles 5 were present, and the culture solution containing the produced glutamic acid was extracted from the discharge pipe 8.

Furthermore, the air inside the apparatus was discharged once through the discharge pipe 9.

When the air supply is stopped, the carrier particles 5 with the microorganisms attached float to the upper part of the device 3 and remain at the lower part of the distributor 4, but when the medium is circulated by the air supply,
The carrier particle packed bed expands.

In this experiment, the expansion rate was set to 2 times the maximum.

Two months after the start of the experiment, all the carrier particles in the device were taken out, the microbial type El attached to the particles was determined as a dry weight, and the degree of attached microorganisms per volume of carrier particles was calculated to determine the superiority or inferiority of microbial adhesion. evaluated.

Note that the weight of microorganisms attached to carrier particles is 2 at 105°C.
After drying for 4 hours, the weight was determined. The results are shown in Table 1.

Table 1 1 811.1 812゜5 1,4 7002 72
0.3 731.8 1f, 5 57503 661.
4 686,7 25.3 1.2650 (weight is 21
5K per carrier particle) From the table, it is clear that carrier particles 1 with a smooth surface do not attract much microorganisms due to the flow of the carrier particles, but carrier particles 21 with a rough surface have a relatively high degree of microorganisms. adhere to. Furthermore, in the case of the carrier particles 3 of the present invention, significantly more microorganisms are attached and retained than in the carrier particles 2.

Example 2 Using carrier particles 3 in Example 1 as carrier particles, the gelcol concentration of the medium was adjusted to 5% by weight using the apparatus shown in Example 1.
Glutamine Q fermentation was carried out continuously for two months under the same conditions as in Example 1, except that the pH was 7 to 8 and the culture temperature was 32°C.

As a result, the average was 2. Production of glutamic acid was observed at the z5M5M amount ratio.

Example 3 Commercially available baker's yeast (Saccharomyces cerevisiae) was attached to the carrier particles 3 of Example 1, and cultured in a medium containing glucose as a carbon source to produce ethanol.

The experimental device was a glass device (diameter 15 mm) shown in Figure 5.
CIrL, height 30crn, effective reaction tank volume approximately 4A')
Using a circulation pump IIK, the liquid in the suspension was circulated through line 12 to create a downward flow, and a portion of the culture solution was extracted from line 8. Further, the produced gas was discharged from 9. In the figure, 1 is a medium supply line, 2 is a bonder,
3 is the device, and 5 is the 411-body particle.

The experiment was conducted continuously for two months under the following conditions.

Temperature: 30°C pH: approx. 5.5 Glucose concentration: 20M amount % Medium supply rate: 1.4 A/br Carrier particle filling amount: 21 Culture solution circulation rate: 50 to 2001/hr As a result, the average concentration of ethanol in the culture solution is 6. 4M amount%, reaction rate per unit volume is 229 ethanol/1j-hr
Met. Furthermore, the amount of baker's yeast attached to the shuntai particles was 26 per 11 carrier particles.

[Brief explanation of drawings]

Figure 1 a''-t is a sectional view showing the aspect of the base material constituting the carrier particles of the present invention, Figure 2 is a sketch diagram showing an example of the 111-body particles of the present invention, and Figures 3 a and b are the carrier particles. It is an explanatory diagram of a state in which sanitary substances are attached to particles, where a shows the state before fluidization or mixing, and b shows the state after fluidization or warming. Figures 4 and 5 show the experimental equipment used in the example. This is an explanatory diagram. Patent applicant Chiyoda Corporation Yosha Fig. 1 (Q) (1)) (c) Fig. 2 Fig. 4q ”) (b) Fig. 5 3

Claims (1)

[Scope of Claims] 1. Carrier particles formed by winding threads or fibers around a synthetic resin base material having notches on the outer surface. 2. The carrier particles according to claim 1, wherein the synthetic resin base material has a length of 1 to 501 m and a diameter of 1 to 50 mm.