Xenorhabdus nematophila secretes insecticidal proteins to kill its larval prey. We have isolated an approximately 58-kDa GroEL homolog, secreted in the culture medium through outer membrane vesicles. The protein was orally insecticidal to the major crop pest Helicoverpa armigera with an LC50 of approximately 3.6 microg/g diet. For optimal insecticidal activity all three domains of the protein, ...

A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae ...

In this study a series of diacylhydrazine and acylhydrazone derivatives were designed and synthesized according to the method of active group combination and the principles of aromatic group bioisosterism. The structures of the novel derivatives were determined on the basis on 1H-NMR, IR and ESI-MS spectral data. All of the compounds were evaluated for their in vivo insecticidal activity agains...

The use of Bacillus thuringiensis (Bt) strains with high insecticidal activity is essential for the preparation of bioinsecticide. In this study, for 60 Bt strains isolated in Taiwan, their genotypes and the correlation of some cry genes as well as the expression levels of cry1 genes, with their insecticidal activities against Plutella xylostella, were investigated. Pulsed field gel electrophor...

Batch and fed-batch cultivation of Bacillus thurillgiellsis var. kurstaki was carried out to achieve high cell and spore density with maximum insecticidal activity. Cell cultivation was done in fully equipped fermentors under controlled conditions at different feed rates. Increased cell mass, high spore counts and improved insecticidal activity were achieved with fed-batch cultivation system. W...

Griffonia simplicifolia leaf lectin II (GSII), a plant defense protein against certain insects, consists of an N-acetylglucosamine (GlcNAc)-binding large subunit with a small subunit having sequence homology to class III chitinases. Much of the insecticidal activity of GSII is attributable to the large lectin subunit, because bacterially expressed recombinant large subunit (rGSII) inhibited gro...

Quassin and 8 congeners, 1-9, were identified as active principles in Picrasma quassioides for the paralytic/acute insecticidal activity upon subcutaneous injection in the American cockroach. The activity was prolonged by applying the metabolic inhibitors for oxidation and esterification before injecting the quassinoids. The nature of the insecticidal activity seems to differ from that of other...

Synthetic sugar esters are a relatively new class of insecticidal compounds that are produced by reacting sugars with fatty acids. The objective of this research was to determine how systematic alterations in sugar or fatty acid components of sugar ester compounds influenced their insecticidal properties. Sucrose octanoate, sorbitol octanoate, sorbitol decanoate, sorbitol caproate, xylitol octa...

The neonicotinoids are the newest major class of insecticides modeled after the basic nicotine molecule having improved insecticide activity and generally low toxicity. The insecticidal activities of neonicotinoids were previous studied using 3D and standard partial least squares regression models. The paper describes the ability of the MDF SAR methodology in prediction of insecticidal activiti...

A series of 2'(2',6')-(di)halogeno-isoxazolopodophyllic acids-based esters, and oxime sulfonates of 2'(2',6')-(di)halogenopodophyllones were prepared by structural modifications of podophyllotoxin as insecticidal agents against Mythimna separata Walker. It was found that when 2'(2',6')-(di)halogenopodophyllones or 2'(2',6')-(di)chloropicropodophyllones reacted with hydroxylamine hydrochloride, ...