Hamadan University of Medical Sciences Avicenna Journal of Medical Biochemistry 2345-4113 4 1 2016 06 01 Assessment of Behavior of Rice Root Peroxidase in the Presence of Silver Nanoparticles 3 30943 10.17795/ajmb-30943 EN Somaye Mohammadzade Arezoo Beig Parikhani Hossein Askari Journal Article 10.17795/ajmb-30943 2015 07 08 2015 10 11 Background: Silver Nanoparticles (AgNPs) can change proteins function and structure. The increased production and high surface reactivity of silver nanoparticles, has interested researchers to study the interactions of these particles with biomolecules. Objectives: The present study aimed to show the effects of AgNPs on rice plant root peroxidase enzyme and the interaction quality between silver nanoparticles and the enzyme. Materials and Methods: Extracted peroxidase enzyme of rice plant root was treated by AgNPs at concentrations of 0, 20, 40, 80, 100mg/L for 2, 7 and 24 hours. The experiment was done with 15 treatments for measuring the peroxidase enzyme activity using the spectrophotometry method at a wavelength of 470. Results: Lowconcentrations of AgNPsandshort incubation times can have themaximumpositive impactonthe peroxidase activity, and in the present study the highest activity was seen at a concentration of 40 mg/L and two hours of incubation time. Conclusions: This study suggests that changes of enzymeactivity can occur as a result of the effect of silver nanoparticlesonenzyme conformation, increase of reactive environment pH, and amount of substrate and enzyme stability.