CN-118308220-B - Bacterial strain capable of degrading PBAT plastic at normal temperature and application thereof

Abstract

The invention provides an Aspergillus niger F2 capable of efficiently degrading PBAT at normal temperature, which is classified as Aspergillus niger (Aspergillus niger) and preserved in China general microbiological culture collection center (CGMCC) with the addresses of North Star Xiyu No. 1, 3 in the Chaoyang area of Beijing city, CGMCC No.40926 and the preservation time of 2023, 11 months and 17 days. According to the measurement, the degradation rate of the Aspergillus niger F2 on the PBAT film is 63% after 56 days of degradation at 20-25 ℃, and the degradation rate of the PBAT powder can reach 63% after 10 days and 91% after 30 days. The Aspergillus niger F2 degradation PBAT plastic has the advantages of high efficiency, simplicity, convenience, low cost and environmental protection, and has great application potential in the aspect of PBAT agricultural film degradation.

Inventors

• CAI JINLING
• FENG FEI
• LI JIAXIN

Assignees

• 天津科技大学

Dates

Publication Date

20260505

Application Date

20240418

Claims (4)

1. 1. Aspergillus niger (Aspergillus niger) F2 capable of degrading PBAT at normal temperature is preserved in China general microbiological culture Collection center (CGMCC), the preservation number is CGMCC No. 40926, and the preservation time is 2023, 11, 17.
2. 2. Use of aspergillus niger F2 according to claim 1 for degrading PBAT plastics at normal temperature.
3. 3. The application of aspergillus niger F2 in degrading PBAT plastic at 20-25 ℃ according to claim 1.
4. 4. The method of degrading PBAT plastic with Aspergillus niger F2 as set forth in claim 1, wherein the PBAT plastic is PBAT powder or PBAT film.

Description

Bacterial strain capable of degrading PBAT plastic at normal temperature and application thereof Technical Field The invention relates to the technical field of plastic degradation, in particular to a bacterial strain capable of efficiently degrading PBAT plastic at normal temperature and application thereof. Background The plastic product brings great convenience to human life and causes great pollution to the environment due to the difficulty in degradation. The plastic waste reaches about 6200 tens of thousands of tons in 2019 as a large country for plastic production and sales. By 2050, global plastic cumulative yields will be expected to reach 340 million tons, with annual plastic waste being about 3 million tons, and corresponding waste disposal will place tremendous pressure on global environmental remediation. In order to alleviate the problem of plastic pollution, various measures are taken in China, including actively popularizing recyclable, easily-recoverable and degradable substitute products, standardizing recycling of plastic wastes and the like. Wherein the use of degradation products, in particular biodegradable plastic articles, is an effective solution to the problem of contamination of a part of the disposable plastic articles. The most commonly used degradable plastics on the market today mainly include polybutylene terephthalate adipate (PBAT), polylactic acid (PLA) and thermoplastic starch (TPS). Wherein, PBAT is formed by polycondensation of adipic acid, butanediol and terephthalic acid, contains a rigid side group consisting of a longer hydrocarbon flexible chain and an aromatic benzene ring, and has better ductility (elongation at break > 700%). PBAT is a fully biodegradable aromatic polyester, the most widely used degradable plastic at present, and its annual production has increased from 1.19 ten thousand t in 2011 to 3.38 ten thousand t in 2018. According to comprehensive agricultural film development trend and plastic pollution prevention and control policy prediction analysis, the annual yield of the PBAT mulching film keeps increasing and exceeds 30 ten thousand t per year. Although PBAT is a degradable material, its degradation effect is not ideal in practical application. The conjugated structure of the PBAT benzene ring enables positive charges of carbonyl carbon atoms to be delocalized, so that the sensitivity of chemical bonds to the hydrolysis process is reduced, and meanwhile, the steric hindrance effect of the aromatic structure reduces the accessibility of water molecules capable of hydrolyzing the chemical bonds, so that the PBAT is difficult to degrade and has low degradation rate. If the PBAT mulch film paved in the crop planting process is not subjected to effective degradation treatment after the use, the accumulation of the waste PBAT mulch film in farmlands can seriously affect the ecological environment of soil, so that the yield of crops is reduced (Jiang and the like, 2017. The coverage of the PBAT biodegradable film has influence on the hydrothermal and yield of cotton soil in oasis drip irrigation, agricultural engineering report. 33 (16), 135-143). The existing treatment method of the degradable plastics mainly adopts the modes of incineration, landfill and industrial composting. The landfill operation is simple, the treatment capacity is large, but a large amount of land is occupied, the garbage is not reduced, and the pollution source is not effectively treated. The incineration decrement is obvious, but the toxic pollution of dioxin is easy to generate, and the environmental and human health are greatly harmed. According to ISO 14855-1/2, industrial compost is required to continuously maintain the temperature of 58 ℃, the experimental period is not more than 6 months, the generation amount of CO 2 is used as a judging index of plastic degradation efficiency, the industrial aerobic compost can degrade PBAT under the high temperature condition of (58+/-2) DEGC to obtain a better degradation effect (Ma is super-equal, 2021. The microbial response PBAT-PLA biodegradable film bag industrial aerobic composting degradation mechanism. Agricultural engineering theory. 37 (24), 224-231), but the energy required to be consumed for maintaining the high temperature condition is higher, the reaction condition is not easy to control, and the general site is difficult to reach the index condition. At present, researches generally show that the effect of degrading PBAT by microorganisms at normal temperature is poor. Huo Xiangdong et al reported that the actual degradation rate of PBAT particles reaches 0.92% (Huo Xiangdong et al, 2017. Separation identification and degradation capability measurement of polybutylene terephthalate-adipate (PBAT) degrading bacteria after 60 days of culture at 30 ℃ and 150 rpm. Xinjiang agricultural science. 54 (11), 2086-2091). Liu Jiaqian to obtain 6 PBAT degrading strains, wherein after the Pseudomonas sp.RD1-3 and the Pseudomonas sp.