小麦根系吸收萘、菲、芘的动力学特征
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摘要
研究植物根系吸收多环芳烃的动力学特征对控制其进入食物链、保障农产品安全有重要意义.因此,本文采用水培方法,研究了小麦根系对萘、菲、芘吸收的动力学机制.结果表明,小麦根系对水培环境中的萘、菲和芘均有明显的吸收和累积作用,且吸收量均随时间延长而增加,整个吸收过程可分为快速吸收和慢速吸收两个阶段.小麦根系对萘、菲和芘的吸收速率快慢表现为芘>菲>萘,且萘、菲、芘吸收的动力学曲线可用米氏方程表征,相应的Km值分别为759.30、12.89和3.59μmol·L-1,即小麦对萘、菲、芘的亲和力大小为芘>菲>萘,结果与其Kow值大小顺序一致.小麦根系吸收萘、菲、芘均会导致营养液pH值升高,吸收单个萘、菲、芘分子产生的pH升高幅度表现为芘>菲>萘.上述结果显示,萘、芘的根系吸收特征与菲相似.
Understanding the kinetic characteristics of polycyclic aromatic hydrocarbon(PAH)uptake by plant roots is important in revealing the mechanism of PAH uptake,and further in taking agronomic measures to reduce PAH accumulation in crops for a better food safety.Hydroponic experiments were employed to investigate the uptake of naphthalene,phenanthrene and pyrene(three representatives of PAHs)by wheat roots.Wheat roots can take up the three PAHs from Hoagland nutrient solution and the three PAHs absorbed by roots increase with incubation time.The uptake process consists of two sequential phases,a fast accumulation process and a slow one.The ability of wheat roots to take up the three PAHs is in the order of pyrene > phenanthrene > naphthalene.Concentration-dependent uptake of the three PAHs by wheat roots can be described with Michaelis-Menten equation and the Km values for naphthalene,phenanthrene and pyrene are 759.30,12.89 and 3.59 μmol·L-1,respectively.The affinity of the three PAHs to wheat root carrier proteins is pyrene > phenanthrene > naphthalene.The order of the affinity for the three PAHs is consistent with that of the Kow.Solution pH increases due to naphthalene,phenanthrene and pyrene uptake,and the order of increase in pH per molecule of the three PAHs absorbed is pyrene > phenanthrene > naphthalene.The trend in pH increase is in good agreement with that in affinity.Therefore,it is concluded that the uptake of naphthalene and pyrene by wheat roots is similar to that of phenanthrene.
Understanding the kinetic characteristics of polycyclic aromatic hydrocarbon(PAH)uptake by plant roots is important in revealing the mechanism of PAH uptake,and further in taking agronomic measures to reduce PAH accumulation in crops for a better food safety.Hydroponic experiments were employed to investigate the uptake of naphthalene,phenanthrene and pyrene(three representatives of PAHs)by wheat roots.Wheat roots can take up the three PAHs from Hoagland nutrient solution and the three PAHs absorbed by roots increase with incubation time.The uptake process consists of two sequential phases,a fast accumulation process and a slow one.The ability of wheat roots to take up the three PAHs is in the order of pyrene > phenanthrene > naphthalene.Concentration-dependent uptake of the three PAHs by wheat roots can be described with Michaelis-Menten equation and the Km values for naphthalene,phenanthrene and pyrene are 759.30,12.89 and 3.59 μmol·L-1,respectively.The affinity of the three PAHs to wheat root carrier proteins is pyrene > phenanthrene > naphthalene.The order of the affinity for the three PAHs is consistent with that of the Kow.Solution pH increases due to naphthalene,phenanthrene and pyrene uptake,and the order of increase in pH per molecule of the three PAHs absorbed is pyrene > phenanthrene > naphthalene.The trend in pH increase is in good agreement with that in affinity.Therefore,it is concluded that the uptake of naphthalene and pyrene by wheat roots is similar to that of phenanthrene.
引文
Chapin F S,Moilanen L,Kielland K.1993.Preferential use of organicnitrogen for growth by a non-mycorrhizal article sedge[J].Nature,361:150-153
陈思杨,江荣风,李花粉.2011.苗期小麦和水稻对硒酸盐/亚硒酸盐的吸收及转运机制[J].环境科学,32(1):284-289
Gao Y,Yu X Z,Wu S C,et al.2006.Interactions of rice(Oryza sativaL.)and PAH-degrading bacteria(Acinetobacter sp.)on enhanceddissipation of spiked phenanthrene and pyrene in waterlogged soil[J].Science of the Total Environment,372:1-11
Hans-Holger L,Martin A,2000.Accumulation of phenanthrene andpyrene in rhizosphere soil[J].Chemosphere,40:11-14
胡顺利,贾凌云,高慧鹏,等.2011.土壤中不同有机质对菲的吸附行为及生物可利用性的影响[J].环境科学学报,31(2):341-348
焦杏春,陈素华,沈伟然,等.2006.水稻根系对多环芳烃的吸着与吸收[J].环境科学,27(4):760-764
Johnson D L,Jones K C,Langdon C J,et al.2002.Temporal changes inearthworm availability and extractability of polycyclic aromatichydrocarbons in soil[J].Soil Biol and Biochem,34(9):1363-1370
Jones K C,Grimmer G,Jacob J,et al.1989.Changes in thepolynuclear aromatic hydrocarbon content of wheat grain and pasturegrassland and over the last century from one site in the U.K.[J].The Science of the Total Environment,78:117-130
Kvesitadze E,Sadunishvili T,Kvesitadze G.2009.Mechanisms oforganic contaminants uptake and degradation in plants[J].WorldAcademy of Science,Engineering and Technology,55(6):458-468
Kipopoulou A M,Manoli E,Samara C.1999.Bioconcentration ofpolycyclic aromatic hydrocarbons in vegetables grown in an industrialarea[J].Environmental Pollution,106(3):369-380
梁宵,占新华,周立祥.2012.不同作物根系多环芳烃吸收特征差异的比较研究%[J].环境科学,33(7):2516-2521
Lin H,Tao S,Zuo Q,et al.2007.Uptake of polycyclic aromatichydrocarbons by maize plants[J].Environmental Pollution,148(2):614-619
Muratova A,Golubev S,Dmitrieva T,et al.2009.Effect of thepolycyclic aromatic hydrocarbon phenanthrene on root exudation ofSorghum bicolor(L.)Moench[J].Environmental andExperimental Botany,66:514-521
McKone T E,Ryan P B.1989.Human exposure to chemicals throughfood chains:an uncertainty analysis[J].Environmental Science andTechnology,23(9):1154-1163
McLachlan M S.1996.Bioaccumulation of hydrophobic chemicals inagricultural food chains[J].Environmental Science andTechnology,30(1):252-259
莫丹,袁兴中,曾光明,等.2008.Tween80和鼠李糖脂对稻草酶解的影响[J].环境科学,29(7):1198-2004
Simonich S L,Hites R A.1994.Vegetation atmosphere partitioning ofpolycyclic hydrocarbons[J].Environmental Science andTechnology,28:939-943
Su Y H,Zhu Y G.2007.Transport mechanisms for the uptake of organiccompounds by rice(Oryza sativa)roots[J].EnvironmentalPollution,148(1):94-100
Tao S,Jiao X C,Chen S H,et al.2006.Accumulation and distributionof polycyclic aromatic hydrocarbons in rice(Oryza sativa)[J].Environmental Pollution,140(3):406-415
田霄鸿,李生秀,王清君.2001.几种作物NO3-吸收动力学参数测定方法初探[J].土壤通报,32(1):16-18
万寅婧,占新华,周立祥.2005.土壤中芘、菲、萘、苯对小麦的生态毒性影响[J].中国环境科学,25(5):563-566
王戎,何杞双,王雁,等.2009.可溶性有机物对玉米根部菲与芴吸着与吸收过程的影响[J].农业环境科学学报,28(1):35-39
Watts A W,Ballestero T P,Gardner K H.2006.Uptake of polycyclicaromatic hydrocarbons(PAHs)in salt marsh plants Spartinaalterniflora grown in contaminated sediments[J].Chemosphere,62(8):1253-1260
杨春璐,孙铁珩,和文祥.2008.汞、豆磺隆复合污染对土壤脲酶活性及动力学特征的影响[J].生态学杂志,27(5):740-744
杨艳,凌婉婷,高彦征,等.2010.几种多环芳烃的植物吸收作用及其对根系分泌物的影响[J].环境科学学报,30(3):593-599
Zhan X H,Ma H L,Zhou L X,et al.2010.Accumulation ofphenanthrene by roots of intact wheat(Triticum acstivnm L.)seedlings:passive or active uptake?[J].BMC Plant Biology,10:52
占新华,周立祥,万寅婧,等.2006.水溶性有机物对植物吸收菲的影响及其机制研究[J].环境科学,27(9):1184-1188
Zhan X H,Zhang X B,Yin X,et al.2012.H+/phenanthrenesymporter and aquaglyceroporin are implicated in phenanthreneuptake by wheat(Triticum aestivum L.)roots[J].Journal ofEnvironmental Quality,41:188-196
张晓斌,占新华,周立祥,等.2011.小麦/苜蓿套作条件下菲污染土壤理化性质的动态变化[J].环境科学,32(5):1462-1470
陈思杨,江荣风,李花粉.2011.苗期小麦和水稻对硒酸盐/亚硒酸盐的吸收及转运机制[J].环境科学,32(1):284-289
Gao Y,Yu X Z,Wu S C,et al.2006.Interactions of rice(Oryza sativaL.)and PAH-degrading bacteria(Acinetobacter sp.)on enhanceddissipation of spiked phenanthrene and pyrene in waterlogged soil[J].Science of the Total Environment,372:1-11
Hans-Holger L,Martin A,2000.Accumulation of phenanthrene andpyrene in rhizosphere soil[J].Chemosphere,40:11-14
胡顺利,贾凌云,高慧鹏,等.2011.土壤中不同有机质对菲的吸附行为及生物可利用性的影响[J].环境科学学报,31(2):341-348
焦杏春,陈素华,沈伟然,等.2006.水稻根系对多环芳烃的吸着与吸收[J].环境科学,27(4):760-764
Johnson D L,Jones K C,Langdon C J,et al.2002.Temporal changes inearthworm availability and extractability of polycyclic aromatichydrocarbons in soil[J].Soil Biol and Biochem,34(9):1363-1370
Jones K C,Grimmer G,Jacob J,et al.1989.Changes in thepolynuclear aromatic hydrocarbon content of wheat grain and pasturegrassland and over the last century from one site in the U.K.[J].The Science of the Total Environment,78:117-130
Kvesitadze E,Sadunishvili T,Kvesitadze G.2009.Mechanisms oforganic contaminants uptake and degradation in plants[J].WorldAcademy of Science,Engineering and Technology,55(6):458-468
Kipopoulou A M,Manoli E,Samara C.1999.Bioconcentration ofpolycyclic aromatic hydrocarbons in vegetables grown in an industrialarea[J].Environmental Pollution,106(3):369-380
梁宵,占新华,周立祥.2012.不同作物根系多环芳烃吸收特征差异的比较研究%[J].环境科学,33(7):2516-2521
Lin H,Tao S,Zuo Q,et al.2007.Uptake of polycyclic aromatichydrocarbons by maize plants[J].Environmental Pollution,148(2):614-619
Muratova A,Golubev S,Dmitrieva T,et al.2009.Effect of thepolycyclic aromatic hydrocarbon phenanthrene on root exudation ofSorghum bicolor(L.)Moench[J].Environmental andExperimental Botany,66:514-521
McKone T E,Ryan P B.1989.Human exposure to chemicals throughfood chains:an uncertainty analysis[J].Environmental Science andTechnology,23(9):1154-1163
McLachlan M S.1996.Bioaccumulation of hydrophobic chemicals inagricultural food chains[J].Environmental Science andTechnology,30(1):252-259
莫丹,袁兴中,曾光明,等.2008.Tween80和鼠李糖脂对稻草酶解的影响[J].环境科学,29(7):1198-2004
Simonich S L,Hites R A.1994.Vegetation atmosphere partitioning ofpolycyclic hydrocarbons[J].Environmental Science andTechnology,28:939-943
Su Y H,Zhu Y G.2007.Transport mechanisms for the uptake of organiccompounds by rice(Oryza sativa)roots[J].EnvironmentalPollution,148(1):94-100
Tao S,Jiao X C,Chen S H,et al.2006.Accumulation and distributionof polycyclic aromatic hydrocarbons in rice(Oryza sativa)[J].Environmental Pollution,140(3):406-415
田霄鸿,李生秀,王清君.2001.几种作物NO3-吸收动力学参数测定方法初探[J].土壤通报,32(1):16-18
万寅婧,占新华,周立祥.2005.土壤中芘、菲、萘、苯对小麦的生态毒性影响[J].中国环境科学,25(5):563-566
王戎,何杞双,王雁,等.2009.可溶性有机物对玉米根部菲与芴吸着与吸收过程的影响[J].农业环境科学学报,28(1):35-39
Watts A W,Ballestero T P,Gardner K H.2006.Uptake of polycyclicaromatic hydrocarbons(PAHs)in salt marsh plants Spartinaalterniflora grown in contaminated sediments[J].Chemosphere,62(8):1253-1260
杨春璐,孙铁珩,和文祥.2008.汞、豆磺隆复合污染对土壤脲酶活性及动力学特征的影响[J].生态学杂志,27(5):740-744
杨艳,凌婉婷,高彦征,等.2010.几种多环芳烃的植物吸收作用及其对根系分泌物的影响[J].环境科学学报,30(3):593-599
Zhan X H,Ma H L,Zhou L X,et al.2010.Accumulation ofphenanthrene by roots of intact wheat(Triticum acstivnm L.)seedlings:passive or active uptake?[J].BMC Plant Biology,10:52
占新华,周立祥,万寅婧,等.2006.水溶性有机物对植物吸收菲的影响及其机制研究[J].环境科学,27(9):1184-1188
Zhan X H,Zhang X B,Yin X,et al.2012.H+/phenanthrenesymporter and aquaglyceroporin are implicated in phenanthreneuptake by wheat(Triticum aestivum L.)roots[J].Journal ofEnvironmental Quality,41:188-196
张晓斌,占新华,周立祥,等.2011.小麦/苜蓿套作条件下菲污染土壤理化性质的动态变化[J].环境科学,32(5):1462-1470