Molecular interaction of peanut proteins with some bio-pesticides: A comparative spectral study

Department of Chemistry, The University of Burdwan, Golapbag, Burdwan-713 104, West Bengal, India
Department of Chemistry, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata-700 009, India
E-mail: kamalchem.roy@gmail.com
Manuscript received online 15 November 2020, revised and accepted 25 December 2020

Safety and quality of food supplies is an essential part of consumer protection. Due to proven toxicity of synthetic pesticides,
bio-pesticides are slowly capturing the agro-economy. It is now time to evaluate the different aspects of bio-pesticides that
might have effects on different agricultural products. Our interest is to find and compare the effects of some bio-pesticides
on peanut proteins through molecular interaction studies using different spectroscopic methods. Peanuts are chosen as the
model as they are cheap, widely available and grow in direct contact with the soil. In this work, peanut proteins arachin,
conarachin II and conarachin I were extracted, purified and characterized. Interaction study of compounds having biopesticidal
activity viz. azadirachtin obtained from Azadirachta indica and eugenol, estragole and linalool obtained from Ocimum basilicum
are compared for their effects on peanut proteins spectroscopically. Eugenol, estragole and linalool were found to have spectral
interactions with peanut proteins as observed in UV-Visible, fluorescence and CD spectroscopy. The highest interaction was
found for conarachin II with estragole with a binding constant of K = 7.75×10⁴ M^–1 and free energy change of –27.89 kJ. No
interaction of peanut proteins was however observed with azadirachtin.