PDF《第35 卷第 8 期》

第35 卷第

8 期2015 年8月环境科学学报Acta Scientiae Circumstantiae Vol.

35,No.8 Aug.,

2015 基金项目: 嘉兴市科技计划项目(No.2012AY1046) Supported by the Jiaxing Science and Technology Project (No.2012AY1046) 作者简介: 徐(1975―),男,讲师(博士),E?mail: xujie1688@ 126.com;

?通讯作者(责任作者) Biography: XU Jie(1975―), male, lecturer(Ph.D.),E?mail: xujie1688@ 126.com;

?Corresponding author DOI:10.13671 / j.hjkxxb.2014.0922 徐,保积庆.2015.芹菜根细胞壁对镉的吸附固定机制及其 FTIR 表征研究[J].环境科学学报,35(8):2605?2612 Xu J, Bao J Q. 2015.Adsorption and fixation mechanism of cadmium on celery(Apium graveolens L.) root cell wall and the analysis of FTIR spectra[J]. Acta Scientiae Circumstantiae,35(8):2605?2612 芹菜根细胞壁对镉的吸附固定机制及其 FTIR 表征 研究 徐? ,保积庆 嘉兴学院生物与化学工程学院,嘉兴

314001 收稿日期:2014?09?03 修回日期:2014?09?18 录用日期:2014?09?18 摘要:对芹菜根细胞壁 Cd 的吸附固定机制开展了相关研究.芹菜根细胞壁 Cd 吸附的动力学实验研究表明,根细胞壁经酯化改性处理后其对 Cd 的累积吸附量相对降低了 42.6%,经氨基甲基化改性处理后其对 Cd 的累积吸附量相对降低了 21.0%,经果胶酶改性处理后其对 Cd 的累积 吸附量相对降低了 40.5%.同时,利用傅立叶红外光谱技术表征了芹菜根细胞壁上 Cd 吸附位点的官能团信息.研究结果表明,Cd 主要与细胞壁 纤维素、半纤维素和木质素中的羧基官能团发生结合作用,同时,根细胞壁上的蛋白质和果胶质也参与了 Cd 的结合. 关键词:芹菜根细胞壁;

镉;

化学改性;

吸附;

傅里叶红外光谱(FTIR) 文章编号:0253?2468(2015)08?2605?08 中图分类号:X132,X503.2,X171.5 文献标识码:A Adsorption and fixation mechanism of cadmium on celery(Apium graveolens L.) root cell wall and the analysis of FTIR spectra XU Jie? , BAO Jiqing College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing

314001 Received

3 September 2014;

received in revised form

18 September 2014;

accepted

18 September

2014 Abstract: The adsorption and fixation mechanism of cadmium on celery (Apium graveolens L.) root cell wall was investigated. The Cd adsorption kinetics experiments on the celery root cell wall showed that the amount of Cd absorbed by the root cell wall varied after modified treatments compared to the unmodified, reducing by 42.6% after esterifing, 21.0% via aminomethylation and 40.5% with pectinase. Meanwhile by using Fourier transform infrared spectrum, information was characterized about the functional groups of Cd adsorption sites on the celery root cell wall. It was indicated that Cd mainly bound with the carboxyl functional groups in the cellulose, hemicellulose and lignin;

moreover protein and pectin on the root cell wall are also involved in the binding of Cd. Keywords: root cell wall of celery;

cadmium;

chemical modification;

adsorption;

FTIR

1 引言(Introduction) 随着工业的迅猛发展和城市化进程的加快,我 国土壤环境的镉(Cd)污染问题日益突出,调查数据 显示,全国遭受 Cd 污染的农田面积已超过 1.3*104 hm2 , 涉及11 个省市的25 个地区(崔力拓等, 2006).土壤 Cd 污染的来源包括矿物采、选、冶活动 中的烟尘沉降,化肥有机肥的使用、污水灌溉及电 镀废水排放等(刘荣乐等, 2005;

Fischer, 2010;

冉烈 等, 2011).Cd 元素移动性强且毒性大,其在土壤中 的过量累积势必会造成农产品 Cd 含量的增加甚至 超标.有研究表明,大众蔬菜(莴笋、辣椒、茄子、花椰 菜、西红柿、大葱、小白菜、苋菜) 中的 Cd 含量均与 生长环境中的 Cd 浓度之间存在着一定的正相关性 (刘杨等, 2011;