KR-20260064791-A - Pseudomonas fildesensis PC31 strain having plastic degradation activity and uses thereof

Abstract

The present invention relates to a Pseudomonas fildesensis PC31 strain having plastic degradation ability and the use thereof. Specifically, the present invention relates to a Pseudomonas fildesensis PC31 strain having plastic degradation activity deposited under accession number KCTC 15964BP; a plastic degradation composition comprising the Pseudomonas fildesensis PC31 strain or a culture thereof as an active ingredient; and a plastic degradation method comprising the step of culturing the Pseudomonas fildesensis PC31 strain or a culture thereof with plastic or plastic-containing waste.

Inventors

• 이동준
• 최영호
• 이춘호
• 염수진
• 김현우
• 지원석
• 이지은

Assignees

• 현대자동차주식회사
• 전남대학교산학협력단
• 기아 주식회사

Dates

Publication Date

20260508

Application Date

20241029

Claims (7)

1. Pseudomonas fildesensis PC31 strain having plastic-degrading activity, deposited under accession number KCTC 15964BP.
2. In paragraph 1, The above-mentioned Pseudomonas fildecensis PC31 strain is characterized by growing using plastic as a carbon source.
3. In paragraph 1, The Pseudomonas fildecensis PC31 strain, characterized in that the above plastic is polycarbonate.
4. A plastic-degrading composition comprising the strain of claim 1 or a culture thereof as an active ingredient.
5. In paragraph 4, A composition for decomposing plastic, characterized in that the above plastic is polycarbonate.
6. A method for degrading plastic, comprising the step of culturing the strain of claim 1 or a culture thereof with plastic or plastic-containing waste.
7. In paragraph 6, A method for decomposing plastic, characterized in that the above plastic is polycarbonate.

Description

Pseudomonas fildesensis PC31 strain having plastic degradation activity and uses thereof The present invention relates to a novel Pseudomonas fildesensis PC31 strain having plastic degradation ability and the use thereof. The increase in plastic use is leading to a rise in plastic waste. Plastic waste takes a long time to decompose naturally and increases environmental pollution. Furthermore, the incineration of discarded plastic raises concerns about the massive release of carbon dioxide, which accelerates global warming and climate change. Therefore, to solve these problems, plastic consumption must be reduced and recycling actively implemented. However, the actual recycling rate of plastic currently stands at only 9%, with most of it being landfilled, incinerated, or released into the environment. While landfilling is an easy disposal method, it can cause environmental pollution problems as toxic chemicals are released into the soil and flow into groundwater. Therefore, there is a need for the development of improved plastic waste treatment technologies, and as a solution, attempts are underway to reduce plastic usage and pollution through measures such as regulating plastic use, recycling, increasing the use of biodegradable plastics, and biodegradation by microorganisms. In addition, among these methods, the use of microorganisms has recently been gaining attention. PETase, which can decompose PET plastic, has been discovered and reported, and Carbio, an eco-friendly French company, has succeeded in developing and commercializing a bacterial variant enzyme that decomposes about 90% of PET within 10 hours. However, research results regarding the biodegradation of polycarbonate are still lacking, and there is a need to discover new microorganisms that can decompose plastic more effectively. FIG. 1 is a schematic diagram of the discovery site (A) and strain screening process of the Pseudomonas fildecensis PC31 strain having polycarbonate degradation ability according to the present invention (B). Figure 2 shows the results of an analysis of plastic degradation ability for candidate strains having polycarbonate degradation ability in one embodiment of the present invention. Figure 3 shows the results of confirming the increase in turbidity of the medium after 14 days of culture following inoculation of the novel strain of Pseudomonas fildecensis PC31 of the present invention in a plastic medium (A) and the results of analyzing the degree of growth of the strain according to plastic concentration and culture time (B). Figure 4 shows the preventive molecular structure of polycarbonate altered by the strain. Figure 5 shows the results of analyzing the structural changes of polycarbonate altered by the novel strain of Pseudomonas fildecensis PC31 of the present invention using an FT-IR graph. Compared to the control group, the polycarbonate treated with the novel strain of the present invention showed a decrease in peaks corresponding to the ether group (COC) and the carboxylate group (C=O, -COOH), and the formation of a new hydroxyl group (-OH) was confirmed. Figure 6 shows SEM images of surface changes on polycarbonate films in a group treated with the novel strain of Pseudomonas fildecensis PC31 of the present invention and a group not treated. Figure 7 shows the results of observing the change in water contact angle in a polycarbonate film treated with the novel strain of Pseudomonas fildecensis PC31 of the present invention and a polycarbonate film not treated with the strain. The present invention is characterized by providing a novel strain of Pseudomonas fildesensis PC31 (accession number KCTC 15964BP) having plastic-degrading activity and the use thereof. While researching to discover strains capable of environmentally biodegrading plastics using microorganisms, the inventors selected and identified a strain with excellent polycarbonate degradation activity among strains isolated from sewage sludge collected from a sewage treatment plant, and as a result of analyzing the 16S rRNA base sequence, confirmed that it was a novel strain belonging to Pseudomonas fildesensis that had not been previously known. Accordingly, the inventor named the novel strain isolated and identified in the present invention "Pseudomonas fildecensis PC31" and deposited it with the Korea Biotechnology Research Institute Biological Resource Center (KCTC) on July 12, 2024, and was assigned deposit number KCTC 15964BP. In addition, the inventors analyzed the characteristics of the novel strain Pseudomonas fildecensis PC31 identified in this invention and found that it possesses excellent plastic degradation activity. Furthermore, they confirmed that it grows using plastic, specifically polycarbonate, as a carbon source. Therefore, the Pseudomonas fildesensis PC31 strain of the present invention is characterized by having plastic degradation activity, and the plastic may be selected from the group consisting of polycarbonate (PC), p