Goniothalamin isolated from the indigenous plant, Bryonopsis laciniosa L., was highly effective against the larvae of the mosquito, Culex quinquefasciatus Say, as a mosquitocide. This is the first report of goniothalamin. The structure of the bioactive compound isolated from the EtOAc (CH 3 COOC 2 H 5 ) fraction was established through spectroscopic methods using 1 H-NMR and 13 C-NMR in CDCl 3 . The mass spectrum was also recorded using VG micromass ZAB mass spectrometer.

No abstract

No abstract

75-kDa chitinase, which showed potential as a biocontrol agent against Japanese pine sawyer, was characterized after purification from the integument of the fifth instar larvae of Bombyx mori by chromatography on diethylaminoethyl (DEAE)-Toyoperal 650 (M), hydroxylapatite, and Fractogel EMD DEAE 650 (M) columns. The optimum pH was 6.0 toward N-acetylchitopentaose (GlcNAc5) and 10 toward glycolchitin. The optimum temperature was 60 degrees C toward GlcNAc5 and 25 degrees C toward glycolchitn. The enzyme was stable at pH 7-10 and below 40 degrees C. Kinetic analysis and reaction-pattern analysis using glycolchitin and N-acetylchitooligosacchraides as substrates indicated that 75-kDa chitinase is an endo- or random-type hydrolytic enzyme to produce the beta anomeric product and that it prefers the longer N-acetylchitooligosaccharides, suggesting, together with the N-terminal amino acid sequence, that the 75-kDa chitinase belongs to family 18 of glycosyl hydrolases.