title: Effect of neem limonoids on lactate dehydrogenase (LDH) of the rice leaffolder, Cnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae).
abstract: Neem is derived from the neem tree Azadirachta indica A. Juss. (Meliaceae), and its primary insecticidal component is the tetranortriterpenoid azadirachtin and other limonoids. The effect of neem limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on enzyme lactate dehydrogenase (LDH) activity of the rice leaffolder (RLF) Cnaphalocrocis medinalis (Lepidoptera: Pyralidae) larvae was investigated. There was a decrease in enzyme activity relative to the control at all concentrations tested. When fed a diet of rice leaves treated with neem limonoids in bioassays, gut tissue enzyme, LDH levels in rice leaffolder larvae are affected. These results indicate neem limonoids affect LDH activity. These effects are most pronounced in early instar larvae. Azadirachtin was the most potent in of all the limonoids in all experiments indicating strong enzyme inhibition. Clear dose-response relationships were established with respect to LDH activity.
authors.affiliation: Department of Environmental Engineering, Chonbuk National University, 664-14 1ga Duckjin-Dong Duckjin, Jeonju City, Chola buktho, Chonbuk 561 756, Republic of Korea. senthilkalaidr@hotmail.com
authors.forename: Sengottayan
authors.initials: S
authors.lastname: Senthil Nathan
authors.forename: Kandaswamy
authors.initials: K
authors.lastname: Kalaivani
authors.forename: Paul Gene
authors.initials: PG
authors.lastname: Chung
authors.forename: Kadarkarai
authors.initials: K
authors.lastname: Murugan
mesh_terms: D000818:Animals; D005260:Female; D005989:Glycerides / Q000633:toxicity*; D007770:L-Lactate Dehydrogenase / Q000187:drug effects* / Q000378:metabolism; D036701:Limonins / Q000633:toxicity*; D008297:Male; D009036:Moths; D013329:Structure-Activity Relationship; D013729:Terpenes / Q000633:toxicity*
chemical_list: D005989:Glycerides; D036701:Limonins; D013729:Terpenes; C002443:neem oil; D007770:L-Lactate Dehydrogenase