根系分泌物对漆酶诱导17β-雌二醇聚合转移的影响及机制  

Influencing mechanism of root exudates on laccase-induced 17β-estradiol polymerization transfer

作　　者：肖盛华 郭玉洁 戴蔚 孙凯[1] XIAO Shenghua;GUO Yujie;DAI Wei;SUN Kai(Anhui Province Key Lab of Farmland Ecological Conservation and Nutrient Utilization,Key Laboratory of JiangHuai Arable Land Resources Protection and Eco-restoration,Ministry of Natural Resources,College of Resources and Environment,Anhui Agricultural University,Hefei 230036,China)

机构地区：[1]农田生态保育与养分资源高效利用安徽省重点实验室/自然资源部江淮耕地资源保护与生态修复重点实验室,安徽农业大学资源与环境学院,合肥230036

出　　处：《农业环境科学学报》2025年第3期806-814,共9页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(42277019);安徽省自然科学基金优青项目(2308085Y28)。

摘　　要：以广泛种植的玉米(Zea mays L.)为代表性农作物,选择17β-雌二醇(E2)为环境中典型雌激素,采用批量平衡试验方法,探究了玉米根系分泌物(M-REs)对云芝(Trametes versicolor)漆酶诱导E2转化动力学、产物分布和植物毒性的影响及机制。结果表明:漆酶3 h内能够转化95%以上E2,其转化动力学常数(k)为1.08 h^(-1)。40~80 mg·L^(-1)M-REs抑制了漆酶诱导的E2转化(k=0.82~0.96 h^(-1)),而5~20 mg·L^(-1)M-REs对E2转化表现出促进效果(k=1.14~1.45 h^(-1))。漆酶诱导E2转化的可识别中间产物中不仅含有E2自聚合产物(如二聚体、三聚体和四聚体等低聚物),还包括大量E2和M-REs的共聚合产物(如E2与香草酸、阿魏酸、原儿茶酸、谷氨酸、苯丙氨酸、天冬氨酸和丙氨酸的共二聚体)。随着漆酶诱导聚合反应时间的延长,E2和M-REs中特定的小分子代谢物会产生高度复杂且具有多种功能基团的C—C、C—O—C或C—N—C键结合的共沉淀聚合产物。研究表明,E2和M-REs共沉淀聚合产物不仅有效地缓解了E2对玉米种子的毒害作用,还刺激了玉米根的生长发育,漆酶诱导共聚合转移有望为农作物根际雌激素的净污和解毒提供新思路和途径。In this study,we explored the influencing mechanism of maize root exudates(M-REs)on Trametes versicolor laccase-induced E2 removal kinetics,product distribution,and phytotoxicity by the batch experiments.Results indicated that laccase had a high efficiency in removing E2,with an E2 removal rate exceeding 96%within 3 h,and the removal kinetic constant(k)was 1.08 h^(-1).High concentrations of M-REs(40-80 mg·L^(-1))effectively inhibited laccase-catalyzed E2 removal(k=0.82-0.96 h^(-1)),while low concentrations of M-REs(5-20 mg·L^(-1))had a promoting effect on E2 removal(k=1.14-1.45 h^(-1)).The recognizable intermediate products in the laccase-induced E2 conversion contained not only E2 self-polymerization products(dimers,trimers,and tetramers),but also a large number of E2 and M-REs co-polymerization products,such as the co-dimers of E2 with vanillic acid,ferulic acid,protocatechinic acid,glutamic acid,phenylalanine,aspartic acid,and alanine.As the laccase-induced polymerization time was extended to 5 d,E2 and the specified small metabolites in the M-REs generated highly complex co-precipitated polymers with multiple functional groups by C C,C O C,or C N C covalent binding.These E2 and M-REs co-polymers not only alleviated the toxic effect of E2 on maize seeds,but also stimulated the growth and development of maize roots.Therefore,laccase-induced polymerization transfer may provide a new strategy to purify and detoxify estrogens in the rhizosphere of crops.

关 键 词：玉米根系分泌物 真菌漆酶 17Β-雌二醇 共聚合转移 植物毒性 

分 类 号：X503.231[环境科学与工程—环境工程]