Anticholinesterase Potential of Monoterpenoids on the Whitefly Bemisia tabaci and Their Kinetic Studies

K Zarrad, A Laarif, A Hamouda, I Chaieb, J Mediouni-Ben, Jemâa
2017 J. Agr. Sci. Tech   unpublished
B-biotype Bemisia tabaci is a severe insect pest worldwide in many ornamental, agricultural, and horticultural crops. Control of this insect is obstructed by resistance to many AcetylCholinEsterase (AChE)-inhibiting insecticides, such as organophosphates and carbamates. In the present work, we evaluated the acetylcholinesterase inhibitory activity of six monoterpenoids namely α-pinene, terpineol, linalool, ß-myrcene, nerol and geraniol in vitro and in vivo. Inhibition of AChE of B. tabaci was
more » ... of B. tabaci was measured by colorimetric method. The results showed that all of the monoterpenoids produced AChE inhibitory activity, with IC 50 values ranging from 0.96 to 26.85 mM. Alpha-pinene showed the most potent inhibitory activity (IC 50 = 0.96 mM). Kinetic analysis showed reversible non-competitive type inhibition, revealing that these components might bind both the enzyme alone and the enzyme-substrate. Results demonstrate the AChE inhibitory activity as mode of action of these monoterpenoids at relatively high concentrations. Thus, this could be useful for investigation of new ecofriendly natural insecticidal compounds.