Screening and identification of diuron-degrading strain SL-6 and optimization of degradation conditions
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摘要:目的
明确筛选分离得到的敌草隆降解菌株SL-6生物学分类地位，并优化其降解条件，为降解敌草隆提供新的途径。
方法采用富集培养法从棉田中分离敌草隆降解菌SL-6，并通过16S rDNA及nrdA基因序列分析结合形态学、生理生化特征对其进行鉴定；运用HPLC法检测SL-6菌株对敌草隆的降解效果，研究该菌株在不同敌草隆初始质量浓度、接菌量、蔗糖含量、pH及温度条件下的降解能力并优化降解条件。
结果从棉田土壤中分离得到7株菌株，其中，无色杆菌属Achromobacter菌株SL-6、SL-7和SL-9对敌草隆的降解效果好且消解动态符合消解动力学方程；木糖氧化无色杆菌A. Xylosoxidans SL-6降解效果最佳，第15天的降解率为94.6%。在敌草隆初始质量浓度为200 mg/L、接菌量为15%（φ）、不外加碳源、pH为8.0以及温度为30 ℃时，处理5 d后降解率达93.1%。
结论SL-6菌株能够高效降解敌草隆，可作为新的菌株资源，为进一步研究微生物降解敌草隆奠定基础。
Abstract:ObjectiveThis study was aimed to clarify the biological classification of the diuron-degrading strain SL-6 obtained by screening and isolation, and optimize its degradation conditions for providing a new way to degrade diuron.
MethodDiuron-degrading strain SL-6 was isolated in the soil of cotton field by enrichment culture, and identified by 16S rDNA and nrdA gene sequence analysis combined with morphological, physiological and biochemical characteristics. HPLC method was used to detect the degradation effect of SL-6 strain on diuron, and the degradation abilities of the strain under different initial concentrations of diuron, inoculation amount, sucrose content, pH and temperature conditions were studied and the degradation conditions were optimized.
ResultSeven strains were isolated from soil of cotton field. Among them, Achromobacter strains SL-6, SL-7 and SL-9 had good degradation effects on diuron and the degradation kinetics conformed to the degradation kinetics equation. Among the three strains, A. xylosoxidans SL-6 had the best degradation effect, with the degradation rate of 94.6% on the 15th day. When the initial concentration of diuron was 200 mg/L, inoculation amount was 15% (φ), carbon source was not added, pH was 8.0 and temperature was 30 ℃, the degradation rate reached 93.1% after five days.
ConclusionStrain SL-6 can efficiently degrade diuron, and can be used as a new strain resource. This study provide a basis for further research on microbial degradation of diuron.
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Keywords:
- Diuron /
- Biodegradation /
- Bioremediation /
- Achromobacter xylosoxidans /
- Cultural condition
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图 3 初筛菌株对敌草隆的降解率
Figure 3. Degradation rate of diuron by preliminary screening strains
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图 4 菌株SL-6的常规形态学特征
A:SL-6 LB培养基菌落形态；B:SL-6 LB培养基单菌落形态；C:SL-6革兰氏染色图
Figure 4. Conventional morphological characteristics of strain SL-6
A: SL-6 colony morphology on LB medium; B: SL-6 single colony morphology on LB medium; C: SL-6 gram staining
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图 5 基于16S rDNA序列的菌株SL-6与相关菌种的系统发育进化树
Figure 5. Phylogenetic tree of strain SL-6 and related strain species based on 16S rDNA sequence
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图 6 基于nrdA基因序列的菌株SL-6与相关菌种的系统发育进化树
Figure 6. Phylogenetic tree of strain SL -6 and related strain species based on nrdA gene sequence
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图 7 不同培养条件对菌株SL-6降解敌草隆的影响
A：敌草隆初始质量浓度；B：接菌量；C：蔗糖含量；D：pH；E：温度；F：最优条件；图中数据为平均值和标准误(n=3)；各图中，柱子上方的不同小写字母表示差异显著(P < 0.05， Duncan’s法)
Figure 7. Effect of various cultural conditions on diuron degradation by strain SL-6
A: Initial concentration of diuron; B: Inoculation amount; C:Sucrose content; D: pH; E: Temperature; F: Optimal conditions；Data in the figure are means and standard errors (n=3); In each graph, different lowercase letters on bars indicate significant differences(P < 0.05, Duncan’s method)
表 1 敌草隆在培养基中的回收率
Table 1 The recovery rate of diuron in medium
ρ添加/(mg·L−1)
Added concentration回收率/% Recovery rate 相对标准偏差/%
Relative standard deviation (RSD)1 2 3 4 5 平均 Average 25 92.82 96.37 91.23 98.58 94.62 94.72 1.29 50 96.92 90.78 100.02 91.69 92.29 94.34 1.77 100 91.47 102.76 98.22 95.18 97.32 96.99 1.86 
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表 2 敌草隆的消解动力学方程和相关参数
Table 2 Digestion kinetic equation and related parameters of diuron
菌株
Strain消解方程
Degradation equation速率常数
Rate constant (K)决定系数
Coefficient of determination (R2)t半衰/d
Half-lifeSL-6 ρt = 74.482e−0.213t 0.213 0.9636 3.2 SL-7 ρt = 59.264e−0.166t 0.166 0.9782 4.2 SL-9 ρt = 58.165e−0.182t 0.182 0.9691 3.8
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[1] 罗志明, 尹炯, 李俊, 等. 3种农药对蔗田杂草香附子的防除效果及其安全性评价[J]. 农学学报, 2020, 10(11): 7-10. doi: 10.11923/j.issn.2095-4050.cjas20190600088 [2] JACOBSON A R, DOUSSET S, GUICHARD N, et al. Diuron mobility through vineyard soils contaminated with copper[J]. Environmental Pollution, 2005, 138(2): 250-259. doi: 10.1016/j.envpol.2005.04.004
[3] 周先林, 覃琴, 王龙, 等. 脱叶催熟剂在新疆棉花生产中的应用现状[J]. 中国植保导刊, 2020, 40(2): 26-32. doi: 10.3969/j.issn.1672-6820.2020.02.005 [4] GIACOMAZZI S, COCHET N. Environmental impact of diuron transformation: A review[J]. Chemosphere, 2004, 56(11): 1021-1032. doi: 10.1016/j.chemosphere.2004.04.061
[5] DORES E F, SPADOTTO C A, WEBER O L, et al. Environmental behaviour of metolachlor and diuron in a tropical soil in the central region of Brazil[J]. Water, Air, and Soil Pollution, 2009, 197: 175-183.
[6] KHONGTHON W, JOVANOVIC G, YOKOCHI A, et al. Degradation of diuron via an electrochemical advanced oxidation process in a microscale-based reactor[J]. Chemical Engineering Journal, 2016, 292: 298-307. doi: 10.1016/j.cej.2016.02.042
[7] VANRAES P, WARDENIER N, SURMONT P, et al. Removal of alachlor, diuron and isoproturon in water in a falling film dielectric barrier discharge (DBD) reactor combined with adsorption on activated carbon textile: Reaction mechanisms and oxidation by-products[J]. Journal of Hazardous Materials, 2018, 354: 180-190. doi: 10.1016/j.jhazmat.2018.05.007
[8] VERMA J P, JAISWAL D K, SAGAR R. Pesticide relevance and their microbial degradation: A-state-of-art[J]. Reviews in Environmental Science and Bio/Technology, 2014, 13(4): 429-466. doi: 10.1007/s11157-014-9341-7
[9] COELHO-MOREIRA J D S, BRACHT A, SOUZA A C, et al. Degradation of Diuron by Phanerochaete chrysosporium: Role of ligninolytic enzymes and cytochrome P450[J]. BioMed Research International, 2013(1): 251354.
[10] COELHO-MOREIRA J D S, BRUGNARI T, SÁ-NAKANISHI A B, et al. Evaluation of diuron tolerance and biotransformation by the white-rot fungus Ganoderma lucidum[J]. Fungal Biology, 2018, 122(6): 471-478. doi: 10.1016/j.funbio.2017.10.008
[11] MORI T, SUDO S, KAWAGISHI H, et al. Biodegradation of diuron in artificially contaminated water and seawater by wood colonized with the white-rot fungus Trametes versicolor[J]. Journal of Wood Science, 2018, 64(5): 690-696. doi: 10.1007/s10086-018-1740-x
[12] MORETTO J, FURLAN J, FERNANDES A, et al. Alternative biodegradation pathway of the herbicide diuron[J]. International Biodeterioration & Biodegradation, 2019(143): 104716.
[13] SILAMBARASAN S, LOGESWARI P, RUIZ A, et al. Influence of plant beneficial Stenotrophomonas rhizophila strain CASB3 on the degradation of diuron-contaminated saline soil and improvement of Lactuca sativa growth[J]. Environmental Science and Pollution Research, 2020, 27(28): 35195-35207. doi: 10.1007/s11356-020-09722-z
[14] 王伟宝, 王建芳, 谢飞, 等. 张家口地区木糖氧化无色杆菌耐药性的相关基因分析[J]. 现代生物医学进展, 2013, 13(30): 5984-5987. [15] 周野, 王一莹, 李哲, 等. 氧化木糖无色杆菌(Achromobacte rxylosoxidans) LAX2对Cu、Pb和Cd复合污染土壤的生物矿化修复研究[J]. 环境科学学报, 2018, 38(11): 4497-4504. [16] 李哲, 吴迪, 张秀芳, 等. 一株氧化木糖无色杆菌对Cd的固定作用[J]. 西北农林科技大学学报(自然科学版), 2018, 46(9): 91-98. [17] 孙纪全, 黄星, 何健, 等. 异丙隆降解菌Y57的分离鉴定及其降解特性[J]. 中国环境科学, 2006, 26(3): 315-319. doi: 10.3321/j.issn:1000-6923.2006.03.014 [18] 封国君, 王彦辉, 唐文伟, 等. 敌草隆内生降解真菌筛选[J]. 农药学报, 2017, 56(5): 339-343. [19] 杨孟然. 以蚕沙为载体的敌草隆降解菌制剂研究[D]. 广州: 华南农业大学, 2018. [20] MOHAMMED A M, HUOVINEN M, VÄHÄKANGAS K H. Toxicity of diuron metabolites in human cells[J]. Environmental Toxicology and Pharmacology, 2020, 78: 103409. doi: 10.1016/j.etap.2020.103409
[21] HU K, TORÁN J, LÓPEZ-GARCÍA E, et al. Fungal bioremediation of diuron-contaminated waters: Evaluation of its degradation and the effect of amendable factors on its removal in a trickle-bed reactor under non-sterile conditions[J]. Science of The Total Environment, 2020, 743: 140628. doi: 10.1016/j.scitotenv.2020.140628
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