同步辐射μ-XRF用于金银花中砷的吸收分布和转运趋势研究  

Study on the Absorption Distribution and Translocation Trends of Arsenic in Lonicera Japonica Thunb Using Synchrotron Radiation μ-XRF

作　　者：周俊彤 张伊彤 彭聪男 霍清[1] 刘美[1] ZHOU Juntong;ZHANG Yitong;PENG Congnan;HUO Qing;LIU Mei(College of Biochemical Engineering,Beijing Union University,Beijing 100023,China)

机构地区：[1]北京联合大学生物化学工程学院,北京100023

出　　处：《北京联合大学学报》2025年第1期69-77,共9页Journal of Beijing Union University

基　　金：国家自然基金面上项目“道地药材土壤中砷的种态及其再分配机制的原位研究”(11975048)。

摘　　要：金银花因环境因素影响,砷超标问题严重。采用水培法,模拟有机砷与无机砷胁迫,探究金银花的主要酶活性变化,并应用同步辐射X射线荧光光谱(μ-XRF)技术解析砷在金银花中的吸收、分布及转运趋势。使用不同形态不同浓度的砷胁迫金银花植株,测定叶片的生化指标,包括过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD),生化结果显示:在低浓度砷胁迫下,多个生化指标能够积极响应,低浓度无机砷与高浓度有机砷胁迫对POD活性的影响相近,两种形态的砷长时间胁迫,都会使POD显著上升;高浓度有机砷胁迫使CAT急剧下降,表明植物自身的保护机制受损;SOD的变化因砷形态而异,无机砷条件下呈V型波动,有机砷条件下则持续降低,表明植物细胞调节能力受限。μ-XRF分析显示:无机砷主要蓄积于植物的根部表皮层,根与茎共同形成拦截屏障;有机砷主要蓄积于金银花根部维管柱。这为评估重金属污染对药材品质的影响及探索减少药用部位重金属积累策略提供科学依据。Environmental factors significantly impact the accumulation of arsenic in Lonicera japonica Thunb.This thesis employed a hydroponic method to simulate stress from organic and inorganic arsenic and investigate the changes in key enzyme activities in Lonicera japonica Thunb.Furthermore,synchrotron radiation X-ray fluorescence spectroscopy(μ-XRF)was used to analyze the absorption,distribution,and translocation trends of arsenic within the plant.The Lonicera japonica Thunb plants were subjected to arsenic stress at different concentrations and forms,and biochemical indicators of their leaves,including peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD),were measured.The biochemical results showed that under low-concentration arsenic stress,multiple biochemical indices could respond positively.The effects of low-concentration inorganic arsenic and high-concentration organic arsenic stress on POD activity were similar,with prolonged exposure to both forms of arsenic significantly increasing POD activity.High-concentration organic arsenic stress caused a sharp decline in CAT activity,indicating damage to the plant’s protective mechanisms.Changes in SOD activity varied depending on the form of arsenic,with a V-shaped fluctuation under inorganic arsenic conditions and a continuous decrease under organic arsenic conditions,indicating limited cellular regulatory capacity in plants.μ-XRF analysis revealed that inorganic arsenic primarily accumulates in the epidermal cortex of the roots,with the roots and stems forming an interception barrier.In contrast,organic arsenic concentrates in the root center and is mainly distributed in the outer epidermis of the stem.These findings provide scientific evidence for assessing the impact of heavy metal contamination on the quality of medicinal plants and exploring strategies to reduce heavy metal accumulation in medicinal plant parts.

关 键 词：砷 金银花 抗氧化酶 形态分布 

分 类 号：R284.1[医药卫生—中药学] O434.13[医药卫生—中医学]