JPH11206370A - Sustained release resin composition and its usage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition which shows sustained release of an enzyme and/or microorganism as the active ingredient(s) acting on the composition when it is discarded in the nature, e.g. in soil or water, in order to dispense with disposal treatment by including the enzyme and/or microorganism in the biodegradable resin. SOLUTION: This composition is obtained by incorporating (A) a biodegradable resin (e.g. aliphatic polyester) with (B) an enzyme (e.g. hydrolase, oxidoreductase or transferase) and/or microorganism (e.g. microorganism for bioagrochemicals) at a total content of preferably 0.1 to 50 wt.% on the component A, more preferably 1 to 30 wt.%, as the enzyme preparation, microorganism preparation or the like which shows sustained release of the component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the use of enzymes and / or microorganisms, and more particularly to a biodegradable resin composition which releases sustained active ingredients.

[0002]

2. Description of the Related Art When a microorganism or an enzyme is used in a natural environment such as soil or water, such as an enzyme preparation or a microorganism preparation, it is necessary to maintain its effect for a long period of time. For this reason, conventionally, a method of immobilizing an enzyme on various carriers and releasing the enzyme slowly has been proposed (for example, JP-A-6-133774). However, the treatment of the carrier itself has become a problem due to recent environmental concerns. On the other hand, from the viewpoint of environmental problems caused by waste treatment, there has been proposed a sustained-release pesticide formulation comprising a biodegradable resin and a pesticidal active ingredient supported on a carrier (Japanese Patent Laid-Open No. 5-85902).
No.). Attempts have also been made to add biodegradability by adding enzymes and microorganisms that decompose the resin to thermoplastic resins such as polyvinyl alcohol or polyamide (JP-A-6-322216, JP-A-6-3222).
No. 63 gazette).

[0003]

However, the former method is a pesticide, not an enzyme or a microorganism. The latter attempt is intended to impart biodegradability to the non-degradable resin, and does not release enzymes or microorganisms slowly. The present invention has been made in view of such circumstances, and when enzymes and microorganisms are used in an environment such as soil or water, the effects of the enzymes and microorganisms are stably maintained for a longer period of time. An object of the present invention is to provide a resin composition requiring no treatment and a method for using the same.

[0004]

Means for Solving the Problems The present inventors have completed the present invention by including an enzyme and / or a microorganism in a biodegradable resin. That is, the present invention
It is intended to provide a sustained-release resin composition comprising (A) a biodegradable resin containing at least one of (B) an enzyme and / or (C) a microorganism, and a method of using the same.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) biodegradable resin of the present invention is a biodegradable resin,
In particular, it is a resin that is decomposed into low molecular compounds by the involvement of microorganisms. Specific examples include polylactic acid, polyglycolic acid,
Examples thereof include aliphatic polyesters such as polybutyrolactone, polyvalerolactone, polycaprolactone, polyhydroxyalkanoate, and a polycondensate of a diol and a dicarboxylic acid. Examples of polycondensates of a diol and a dicarboxylic acid include polyethylene succinate, polyethylene adipate, polyethylene sebacate, polybutylene succinate, polybutylene adipate, and the like. These resins may be used alone or in combination of two or more. The average molecular weight of the resin used in the present invention is preferably 5,000 to 1,000,000 in terms of polystyrene.

The enzyme (B) in the present invention includes hydrolyzing enzymes such as amylase, protease and lipase; oxidoreductases such as polyphenol oxidase, alcohol dehydrogenase and glucose oxidase;
Examples include transferases such as acetyltransferase, phosphotransferase, and glucosyltransferase.

Further, the microorganism (C) according to the present invention belongs to the genera Pseudomonas, Bacillus, Aspergillus, Streptomyces and the like, and is a microorganism that produces the above enzymes or a genera Pseudomonas, Alcaligenes, Bacillus, Trichoderma, Microorganisms that can be used as biological pesticides such as Dactylella. The mixing ratio of the above enzymes and microorganisms is preferably 0.1 to 50% by weight in the resin composition as a total amount, and particularly preferably 1 to 50% by weight.
30% by weight is preferred.

In producing the resin composition of the present invention, it is preferable to use both enzymes and microorganisms in a dry state. As a result, it is possible to suppress the inactivation of enzymes or the death of microorganisms due to heat. It is more preferable to use the microorganism in a spore state from the viewpoint of heat resistance. As a method for incorporating the enzyme and the microorganism into the biodegradable resin, they may be simply mixed or kneaded. Heating is required at the time of kneading or molding, but it is generally preferable to perform the treatment at 150 ° C. or less for 15 minutes or less, particularly at 130 ° C. or less for 5 minutes or less.

Further, various additives commonly used in the art, such as a plasticizer, a pigment, a flame retardant, a UV stabilizer, an antioxidant, and a lubricant, are added to the resin composition of the present invention. Is also good. The resin composition of the present invention may be formed into a sheet or a film by a molding method generally used in the thermoplastic resin field, such as compression molding, injection molding, extrusion molding, etc., in addition to powder or pellets, to form a desired molding. Can be used as body. Promising applications include wastewater treatment, environmental pollution remediation, and microbial pesticides.

[0010]

The present invention will be described in more detail with reference to the following examples. The lipase activity was determined using a method using olive oil / polyvinyl alcohol emulsion as a substrate.
Specifically, 100 g of a 2% aqueous solution of polyvinyl alcohol (Poval PVA117 (manufactured by Kuraray): Poval PVA205 (manufactured by Kuraray) = 9: 1) is used as an emulsion.
Add olive oil (10g) to the ice cream
pm, and homogenized for 10 minutes. 3 ml of this emulsion, 36.7 mM sodium chloride / 1
3.8 mM calcium chloride solution 30 ml, enzyme solution 0.1
of the mixture at 30 ° C., and the pH was determined by pH stat titration using a 200 mM aqueous sodium hydroxide solution.
Was maintained at 9. At this time, the amount of the enzyme giving the rate at which 1 micromol of sodium hydroxide was titrated in 1 minute was defined as 1 unit (U). The presence or absence of an oily substance was visually indicated in the following three stages. + The oil forms a layer and remains. ± The oil remains in the form of oil droplets.-Almost no oil remains. The disease incidence and control rate in the control effect were calculated by the following formulas. Disease incidence rate (%) = Σ (number of samples × incidence index) / (number of samples × 4) × 100 Control rate (%) = (1−incidence rate of test plot / incidence rate of control plot) × 100 Appeared in the following five stages depending on the degree of browning of the conduit. Healthy whole 0 Browning 1/3 or less 1 Browning 1/3 to 2/3 2 Browning 2/3 or more 3 Dead 4

Further, polycaprolactam having a number average molecular weight of 70,000 (hereinafter referred to as "PCL1"), polycaprolactam having a number average molecular weight of 40,000 (hereinafter referred to as "PCL2") and a number average molecular weight of the biodegradable resin. 30,000 polybutylene succinate-adipate copolymer (hereinafter referred to as “PSA”) was used. Pseudomonas sp. SD705 strain (FERM BP-479
2) (hereinafter referred to as "SD705"), lipase produced from SD705, and Bacillus subtilis SD142 strain (FERM P-13204) (hereinafter referred to as "SD142") as a microorganism.

Example 1 SD705 was cultured in a 20 liter medium containing the following components at a temperature of 35:
C. for 24 hours. Medium components Polypeptone 2% Diammonium hydrogen phosphate 0.2% Dipotassium hydrogen phosphate 0.5% Magnesium sulfate heptahydrate 0.1% Sodium carbonate 0.3% After the culture is completed, the culture solution is freeze-dried. , An enzyme powder was obtained. 40 parts by weight of the obtained enzyme powder and 60 parts by weight of PCL1 powder were uniformly mixed, and the mixture was heated to 80 ° C. and 2 parts by using a hot press molding machine.
A sheet having a thickness of 500 μm was prepared under the conditions of minutes. The obtained sheet was cut into a 3 cm square, immersed in 1 liter of kitchen drainage, and shaken at a constant temperature of 20 ° C. Two days later, the sheet was removed, and the lipase activity in the drainage was measured.
The extracted sheet was immersed in another 1 liter of fresh kitchen drainage. The same test was repeated every two days, for a total of 1
Continued for 4 days. Table 1 shows the results.

Example 2 Culture was carried out in the same manner as in Example 1. After completion of the culture, the cells were centrifuged, and the precipitate was freeze-dried to obtain dried cells. 40 parts by weight of the obtained dried cells and 60 parts by weight of PCL2 powder were uniformly mixed, and a foamed sheet having a thickness of 3 mm was produced at a temperature of 70 ° C. for 3 minutes using a foam molding machine. The obtained sheet was cut into a size of 10 cm × 25 cm, sandwiched between nylon nets, and floated on an upper layer of a kitchen drain trap (capacity: about 200 liters) in which an oily substance was floating. Thereafter, the test was continued for 4 weeks, during which the presence of oily substances was periodically observed. Table 2 shows the results. In addition, coloring (brown) derived from microorganisms or wastewater was observed on the appearance of the wastewater. After the test, biodegradation of the surface layer of the sheet was observed, but the shape was maintained.

Example 3 SD142 was cultured using a medium having the following components. Medium components Glucose 1% Polypeptone 3% Monopotassium dihydrogen phosphate 0.1% Magnesium sulfate / heptahydrate 0.05% pH 7 After centrifuging the obtained culture, spray-dry to dry cells. Was prepared. 1 g of the obtained dried product
There were about 10 ¹² bacteria in them. A mixture of 20 parts by weight of dried cells and 80 parts by weight of PSA pellets was mixed at a temperature of 110 ° C.
After kneading, a pot (diameter: 9 cm) was prepared by injection molding at a temperature of 130 ° C. 28 temperature in bran medium
Contaminated soil was prepared by mixing 5% of the tomato wilt fungus cultivated at 2 ° C with high pressure heat sterilized soil. The pot was filled with about 250 g of soil, seeded with tomato (cultivar: Momotaro) seeds, and raised in a house. Six weeks later, the pot was planted without removing the pot. This is the test plot. As a control, a pot prepared in the same manner as described above without adding dry cells was used. Each processing area 2
Repeatedly, the damage was observed two months after planting. Table 3 shows the results. In both the test and control plots, two months after planting, the pots were decomposed and formed into small pieces, and the initial shape was not maintained at all.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Table 3]

[0018]

Industrial Applicability The sustained-release resin composition of the present invention stably maintains its effects for a long time in an environment such as soil or water in an environment such as soil or water, and does not require waste treatment after use. This is useful.

Claims (7)

[Claims] (1) An enzyme and / or (B) is added to (A) a biodegradable resin.
Or (C) a sustained release resin composition containing at least one microorganism. 2. The sustained-release resin composition according to claim 1, wherein the total content of (B) the enzyme and / or (C) the microorganism is 0.1 to 50% by weight. 3. The sustained-release resin composition according to claim 1, wherein (A) the biodegradable resin is an aliphatic polyester. 4. The sustained-release resin composition according to claim 1, wherein (B) the enzyme is any one of a hydrolase, an oxidoreductase, and a transferase. 5. The sustained-release resin composition according to claim 1, wherein the microorganism (C) is a microorganism used as a biological pesticide. 6. A method for treating oil-containing wastewater, comprising using the resin composition according to claim 4. 7. A method for controlling a plant, comprising using the resin composition according to claim 5.