Screening and performance of phthalate-degrading endophytic floras
In order to reduce the threat to human health of phthalate-contaminated crops,this study attempted to enrich and domesticate functional endogenous flora with high efficiency and broad spectrum of PAEs degradation directly from PAEs-contaminated vegetables.The optimal degradation conditions and the community structure were studied,and the colonization efficiency of functional endophytic flora in crops was studied by hydroponic system.High-throughput sequencing results showed that at the taxonomic level the bacterial consortium consisted of Proteobacteria(76.57%),Bacteroidetes(21.04%)and Actinobacteria(2.37%),and at the generic taxonomic level the bacterial consortium consisted of Sphingobacterium(33.03%),Delftia(40.61%),Pseudomonas(11.70%),Achromobacter(3.04%)and Rhizobium(6.90%).In the pure culture system of inorganic salts,the bacterial consortium could degrade 97.08%dimethyl phthalate(DMP,5mg/L),94.47%diethyl phthalate(DEP,5mg/L),98.02%dibutyl phthalate(DBP,5mg/L)and 44.82%butyl benzyl phthalate(BBP,5mg/L)within 7d.The single-factor test results showed that the optimal degradation conditions were∶ pH 7,25℃,1%salinity and 5mg/L substrate concentration.Hydroponic experiments of rice showed that the bacterial consortium could colonize in the rice and significantly increased PAEs removal,compared with the control group,the contents of DMP,DEP,DBP and ∑ PAEs in rice decreased by 41.09%,45.33%,63.06%and 32.3%within 15d.The colonization of microflora could also increase the root length,plant height and biomass of rice,and promote the growth of rice.The bacterial consortium has a good application prospect in reducing the accumulation of crop PAEs and ensuring the quality and safety of agricultural products in PAEs-contaminated areas,and could effectively reduce the threat of crop PAEs pollution to human health.
万方数据
维普
