• Sadiya Alka
  • Hadiza Musa
  • Abdullahi Salihu
  • Mu'awiya Abarshi Musa



Recently, heavy metals reaching food crops is becoming the world concerns and their effect on humans. To avoid this, plants are used to reduce certain contamination of heavy metals. In this paper, heavy metal concentrations and alpha-amylase activity in plants grown on the contaminated soil was investigated. The objectives of the study were; to evaluate heavy metal concentrations in cowpea plant grown on contaminated soils, to extract and characterize Alpha amylase from the plant. Soil and cowpea plant samples obtained from polluted and unpolluted (control) area, as well as cowpea seed variety samples (7) obtained from IAR ABU Zaria, were digested and analyzed using Atomic Absorption Spectrometer (AAS). The alpha-amylase activity was also determined using a conventional method. Correlation analysis was also done among heavy metals in the soil and the leaves. Michaelis constants (Km) and maximal rates of substrate hydrolysis (Vmax) were determined Using Lineweaver-Burke plot. The plants grown on contaminated soil showed synergistic effect on the removal of Pb 109 mg/ml and Fe 49.5 mg/ml. The result of the correlation analysis for Cu, Pb and Fe showed positive relationships among these heavy metals in both contaminated and uncontaminated soils while Zn showed a negative correlation. The activity of the enzyme 30.0 µmole/min was found to be higher in seeds when compared with other samples. The enzyme optimum pH showed mixed activity due to iso-enzymes. The optimum temperature 600C produced activity of 10 µmole/min. The results imply that, plants growing in the vicinity of land used for military activities may pose some negative effect on the alpha-amylase activity and may affect the food chain.

Keywords: Heavy Metal; Removal; Alpha-Amylase; Cowpea; Military Activities

Author Biographies

Sadiya Alka

1Department of Biochemistry, Faculty of Science, Bauchi State University, Gadau

Hadiza Musa

2Department of Biochemistry, Faculty of Science, University of Maiduguri.

Abdullahi Salihu

3Department of Biochemistry, Faculty of Science, Ahmadu Bello University Zaria.

Mu'awiya Abarshi Musa

3Department of Biochemistry, Faculty of Science, Ahmadu Bello University Zaria.


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