CN-116555122-B - Bacillus proteolyticus and application thereof

Abstract

The invention discloses bacillus proteolyticus and application thereof, and relates to bacteria and application thereof. The invention provides bacillus proteolyticus and application thereof, wherein the bacillus proteolyticus is a bacterium with a function of degrading PBAT (poly (butylene terephthalate)) mulch microplastic. The bacillus proteolyticus L6 is preserved in China general microbiological culture collection center (CGMCC No. 26901). The bacillus proteolyticus L6 can efficiently degrade the PBAT mulch microplastic. The strain lays a good foundation for the development and utilization of degradable mulch microplastic.

Inventors

• YU YONG
• LI YANJUN
• LIN XIAOLONG
• XU GUANGHUI

Assignees

• 中国科学院东北地理与农业生态研究所

Dates

Publication Date

20260512

Application Date

20230605

Claims (2)

1. 1. The bacillus deproteinis (Bacillus proteolyticus) L6 is characterized in that the bacillus deproteinis (Bacillus proteolyticus) L6 is preserved in China general microbiological culture collection center (CGMCC) with the preservation number of CGMCC No.26901.
2. 2. The use of bacillus deproteinis (Bacillus proteolyticus) L6 according to claim 1 for degrading PBAT mulch microplastic.

Description

Bacillus proteolyticus and application thereof Technical Field The invention relates to a bacterium and application thereof. Background The mulching film has the functions of warming, water fixing and retaining, weed and insect prevention, yield increase and the like, and can be used in a large amount in the agricultural production process. Because of the difficult recovery, the mulch plastic can be broken into micro plastic under the actions of cultivation, ultraviolet rays, biodegradation and the like. The microplastic is plastic fragments or particles with the particle size smaller than 5mm, and the microplastic after the mulching film in the soil is broken is mainly poly (adipic acid)/butylene terephthalate (PBAT). The mulch film is used as an important source of farmland soil microplastic as in-situ input microplastic, so that the problem of microplastic pollution is not neglected, and a great threat is formed to an agricultural ecological system. The continuous mulching film covering can lead to directional mutation of soil microorganisms, so that mutant genes capable of degrading the microplastic are reserved, and microplastic degrading bacteria are generated. Therefore, bacterial strains capable of efficiently degrading the mulch film microplastic are obtained through screening degrading bacteria and identifying microbial degradation capability, and theoretical basis and technical support can be provided for pollution control of the microplastic in farmland soil. Has very important significance for relieving and controlling pollution caused by agricultural film micro-plastics and improving soil health and ecological environment. Disclosure of Invention The invention provides bacillus proteolyticus and application thereof, wherein the bacillus proteolyticus is a bacterium with a function of degrading PBAT (poly (butylene terephthalate)) mulch microplastic. The bacillus proteolyticus (Bacillus proteolyticus) L6 is preserved in China general microbiological culture Collection center (CGMCC), and the preservation number is CGMCC No.26901. The bacillus deproteinis (Bacillus proteolyticus) L6 is applied to degradation of PBAT mulch microplastic. The bacillus proteolyticus (Bacillus proteolyticus) L6 is subjected to laboratory simulation, OD 600nm is detected before and after degradation, the PBAT microplastic becomes rough and uneven, obvious corrosion holes, clear cracks and other microscopic forms appear through observation of a scanning electron microscope, and the Fourier infrared spectrum shows that more absorption peaks at 3432cm -1(3500-3100cm-1 area) can be attributed to-OH, so that the bacillus proteolyticus L6 is degraded after introducing polar functional groups into plastics, 2930cm -1,2850cm-1 belongs to methylene characteristic peaks, the peaks at 2925cm -1 of the plastics after L6 treatment are shifted (+2 cm), and the tensile vibration absorption peak of 1761cm -1 of C ═ O is shifted to the bending vibration of a benzene ring skeleton (Vc=c) in a benzene ring C-H plane of 1596cm -1,1137cm-1 and the stretching vibration absorption peak of C-O is shifted to 5cm -1. In addition, there are more absorption peaks at 1461cm -1 and 528cm -1, and 1461cm -1 is flexural vibration in the C-H plane, which indicates that inoculation of Bacillus proteolyticus L6 of the present invention can cause biodegradation of PBAT, resulting in change of chemical functional groups on the surface thereof. The bacillus proteolyticus L6 is added into the PBAT microplastic, the degradation rate of the PBAT microplastic reaches 25.4 percent, and the bacillus proteolyticus L6 has good degradation effect on the PBAT mulch microplastic. The bacillus proteolyticus L6 can efficiently degrade the PBAT mulch microplastic under the 28 ℃ shake culture condition. The strain lays a good foundation for the development and utilization of degradable mulch microplastic. The bacillus proteolyticus (Bacillus proteolyticus) L6 is preserved in China general microbiological culture Collection center (CGMCC), the preservation address is North Star Xiyu No. 1, 3 in the Korean region of Beijing, and the preservation date is 2023, 3 months and 24 days. Drawings FIG. 1 shows the colony morphology of Bacillus deproteinicus (Bacillus proteolyticus) L6 on LB medium; FIG. 2 is a phylogenetic tree of Bacillus proteolyticus (Bacillus proteolyticus) L6; FIG. 3 shows the degradation rate of microplastic after the Bacillus proteolyticus (Bacillus proteolyticus) L6 is inoculated back to the inorganic salt medium; FIG. 4 shows the microscopic morphology of the microplastic after the tie-back of Bacillus proteolyticus (Bacillus proteolyticus) L6 to the inorganic salt medium; FIG. 5 shows the ΔOD600 change of Bacillus proteolyticus (Bacillus proteolyticus) L6 in PBAT mulch microplastic as the sole carbon source; FIG. 6 is a schematic diagram showing the attachment of Bacillus proteolyticus (Bacillus proteolyticus) L6 to the surface of a microplastic observed