| Summary: | 碩士 === 嘉南藥理科技大學 === 環境工程與科學系曁研究所 === 97 === Phenol is a common pollutant with a stable benzene ring from industries, it impacts on the aquatic ecosystem and environmental balance extremely. Biodegradation is a very economic technique leading to the cleavage of benzene ring, which is the best choice of the phenol contaminated soil remediation. The phenol high-tolerance degraders were isolated from collected sludge and soil from petroleum station, the isolated strains in this study including E1, E3, E7, G2, G4, H1, H3, H4, B1 and B3. The physiological properties of tested strains were analyzed by Gram stain, activity of catechol dioxygenase. The results showed that all tested strains owned the activity of catechol 1,2-dioxygenase (C12O). The E1 and E3 were showed 94 and 95 % probability of Bacillus sp. (NRRL B-149911), respectively. H1 was showed 98% probability of Staphylococcus warneri L37603, B1 was showed 92% probability of Geobazillus sp., B3 was showed 98% probability of Bacillus pumilus; E7, G4, H3 and H4 were showed 94% probability of Rhodococcus opacus. Phylogenetic analysis of the test strains was identified by 16S rDNA gene fragment from NCBI database and MEGA software. The result indicated that the test strains are clustered in 2 subgroups from the phylogenic tree constructed by 16 S rDNA.
Inoculation of five effective degraders to the test soil suspensions spiked with phenol was carried out by batch culture. The phenol concentration and the number of phenol degrader were monitored in the experimental period, soil DNA was extracted and amplified by primer 341GC+534r of PCR for DGGE analysis at the same time to understand the growth variation of test strains. The results showed that the effective biodegradations inoculated by test strains were performed in the polluted soils. Tracing soil bacterial community by DGGE-PCR technology in the experimental period was observed that inoculated effective strains became dominant population, and this result was similar to the colony forming unit (CFU) was counted by plate-count methods. The denaturing gradient gel electrophoresis (DGGE) is considered one of the most sensitive scanning techniques for soil community.
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