| 摘要 |
NEW MATERIAL:The glutamic acid receptor-inhibiting substance having the following characteristics. Molecular weight, 500+ or -200; solubility, hardly soluble in ethyl acetate and soluble in water; stability, resistant to the heating at 80 deg.C for 20min in the form of aqueous solution, and resistant to the heating at 80 deg.C for 20 min in a 0.4M perchloric acid; exhibits neutral charge by electrophoresis using 0.01M phosphoric acid buffer solution (pH 7); emits fluorescence by fluorescamine; Rf value, 0.20 by silica gel thin-layer chromatography. USE:Insecticide. Especially effective to rice stem borer, green caterpillar, aphids, etc. PREPARATION:Nephila clavate (silk spider) is collected, disintegrated with an atomizer, etc., and extracted with water, an aqueous solution of electrolyte, or a mixture of water and an organic solvent miscible homogeneously with water. The extract is separated into the liquid and residue by centrifugal separator, etc., and preferably the high-molecular protein is removed. The extract is concentrated under reduced pressure, and purified e.g. by gelfiltration, etc. to obtain the objective glutamic acid receptorinhibiting substance. |
