Assessment of Metal - Induced Inhibition of Soybean Urease as a Tool for Measuring Heavy Metals in Aqueous Samples

Inhibition of soybean (Glycine max) urease by heavy metal ions has been investigated with a view to developing a method for the indirect determination the heavy metals. Urease activity was assayed as a function of metal concentration in the presence of Cd 2+ , Cr 3+ , As 3+ , Cu 2+ , Pb 2+ and Zn 2+ . Our results revealed concentration dependent inhibition of urease activity within the range of 0.001 – 10 mg/L for Cu 2+ , As 3+ , Cr 3+ and Cd 2+ and 0.1 – 10 mg/L for Zn 2+ and Pb 2+ . The inhibitory strengths of the metals as evaluated from their IC50 values showed the following ranking: Cu 2+ > As 3+ > Cr 3+ > Cd 2+ >Zn 2+ > Pb 2+ . Assays for multi-metal solutions revealed similar findings as the single-metal systems but with higher inhibitory strengths. The calibration plots of % inhibition against concentration displayed different linear ranges for the investigated metals; Cu As, Cr and Cd showed linearity within the range of 0.01 – 10mg/L while Zn and Pb plots were linear within 0.1 – 10 mg/L. The applicability of the assay for the quantitative determination of heavy metals was evaluated by analysing synthetic water samples and comparing the results with a standard method (AAS). T-test examination revealed 74% agreement between the two methods. The results of this study show that soybean urease can be valuable for the inhibitive determination of heavy metals in aqueous samples.

[1]  S. Dzyadevych,et al.  INVESTIGATION AND OPTIMIZATION OF REACTIVATION OF UREASE BIOSENSOR FOR HEAVY METALS INHIBITION ANALYSIS , 2015 .

[2]  Sachin Kumar,et al.  Enzyme-based Colorimetric and Potentiometric Biosensor for Detecting Pb (II) Ions in Milk , 2014 .

[3]  A. Ahmad.  The Development Of A Specific Inhibitive Enzyme Assay For The Heavy Metal, Lead , 2013, Journal of Environmental Bioremediation and Toxicology.

[4]  A. Maaref,et al.  Urease capacitive biosensors using functionalized magnetic nanoparticles for atrazine pesticide detection in environmental samples , 2013 .

[5]  S. Nanda,et al.  Remediation of heavy metal contaminated soil , 2013 .

[6]  Madiha Khan,et al.  Kinetics and Thermodynamic Study of Urease Extracted from Soybeans , 2013 .

[7]  Huajie Xu,et al.  Kinetics and mechanism of jack bean urease inhibition by Hg2+ , 2012, Chemistry Central Journal.

[8]  Sujoy Banerjee,et al.  Isolation, partial purification, characterization and inhibition of urease (E.C. 3.5.1.5) enzyme from the Cajanus cajan seeds. , 2012 .

[9]  J. Do,et al.  Preparation of urease/nano-structured polyaniline-Nafion®/Au/Al2O3 electrode for inhibitive detection of mercury ion , 2011 .

[10]  H. Kaur,et al.  Whole cell based disposable biosensor for Cadmium detection in milk , 2011 .

[11]  M. Coelho,et al.  Development of Potentiometric Urea Biosensor based on Canavalia ensiformis Urease , 2011 .

[12]  Xin Yang,et al.  A Disposable Organophosphorus Pesticides Enzyme Biosensor Based on Magnetic Composite Nano-Particles Modified Screen Printed Carbon Electrode , 2010, Sensors.

[13]  Ayten Karaca,et al.  Effects of Heavy Metals on Soil Enzyme Activities , 2010 .

[14]  Priyabrata Pal,et al.  The detection of mercury, cadium, and arsenic by the deactivation of urease on rhodinized carbon. , 2009 .

[15]  P. Bhattacharyya,et al.  Arsenic fractions and enzyme activities in arsenic-contaminated soils by groundwater irrigation in West Bengal. , 2008, Ecotoxicology and environmental safety.

[16]  Rajan Sharma,et al.  A method for estimation of urea using ammonia electrode and its applicability to milk samples , 2008, Journal of Dairy Research.

[17]  B. Krajewska.  Mono- (Ag, Hg) and di- (Cu, Hg) valent metal ions effects on the activity of jack bean urease. Probing the modes of metal binding to the enzyme , 2008 .

[18]  B. Krajewska.  Urease immobilized on chitosan membrane. Inactivation by heavy metal ions , 2007 .

[19]  F. Sangari,et al.  Characterization of the Urease Operon of Brucella abortus and Assessment of Its Role in Virulence of the Bacterium , 2006, Infection and Immunity.

[20]  Guoqing Shen,et al.  Combined effect of heavy metals and polycyclic aromatic hydrocarbons on urease activity in soil. , 2006, Ecotoxicology and environmental safety.

[21]  R. Ilangovan,et al.  Enzyme based Biosensor for Heavy Metal Ions Determination , 2006 .

[22]  W. Lajszner,et al.  The effects of copper on soil biochemical properties and its interaction with other heavy metals , 2006 .

[23]  F. J. Hanus,et al.  Stimulation by nickel of soil microbial urease activity and urease and hydrogenase activities in soybeans grown in a low-nickel soil , 1985, Plant and Soil.

[24]  I. Tothill,et al.  Development of urease and glutamic dehydrogenase amperometric assay for heavy metals screening in polluted samples. , 2004, Biosensors & bioelectronics.

[25]  B. Krajewska,et al.  Heavy Metal Ions Inhibition of Jack Bean Urease: Potential for Rapid Contaminant Probing , 2004, Journal of enzyme inhibition and medicinal chemistry.

[26]  J. Polacco,et al.  Mutational analysis of the embryo-specific urease locus of soybean , 1987, Molecular and General Genetics MGG.

[27]  J. Polacco,et al.  Interallelic Complementation at the Ubiquitous Urease Coding Locus of Soybean1 , 2003, Plant Physiology.

[28]  Z. Krupa,et al.  Functions of Enzymes in Heavy Metal Treated Plants , 2002 .

[29]  Won-Yong Lee,et al.  Determination of heavy metal ions using conductometric biosensor based on sol-gel-immobilized urease , 2002 .

[30]  M. Trojanowicz,et al.  Inhibitive determination of mercury and other metal ions by potentiometric urea biosensor. , 2000, Biosensors & bioelectronics.

[31]  S. Lippard,et al.  Interaction of Urea with a Hydroxide-Bridged Dinuclear Nickel Center: An Alternative Model for the Mechanism of Urease , 2000 .

[32]  R. Dick.  Soil enzyme activities as integrative indicators of soil health. , 1997 .

[33]  B E Dunn,et al.  Purification and characterization of urease from Helicobacter pylori. , 1990, The Journal of biological chemistry.