Patent GB-1106887-A (GB)
Title: Sporicidal agents
Inventor: NORRIS JOHN ROBERT
IPC: C07K14/325
Filed: 1966-06-27
Abstract: Bacterial and fungal cultures, particularly those of insectical protein crystal-forming bacteria such as Bacillus thuringiensis, are rendered substantially free from viable spores by treating them with an olefinically unsaturated aldehyde, particularly acrolein.  The culture is treated with the aldehyde at a concentration of less than 2000 ppm. at a temperature of approximately 30 DEG C. Suspensions of crystal-forming bacteria so treated may be formulated with carriers, surface active agents, wetting agents and liquid or solid diluents to give bacterial insecticide compositions in the form of dusts, granules, briquettes, wettable powders, pastes, solutions, suspensions, emulsions and emulsifiable concentrates.  Examples disclose the sporicidal activity of acrolein on spores of Bacillus thuringiensis, Bacillus subtilis, Aspergillus niger, Penicillium roqueforti and Alternaria brassicicola.  One comparative example demonstrates the insecticidal effect on larvae of cabbage leaves treated with (1) a spore/crystal mixture, (2) the spore/crystal mixture sterilized by treatment with acrolein for 4 hours, (3) the spore/crystal mixture autoclaved at 15 lb./sq. in. for 20 minutes and then treated with acrolein, and (4) a solution of acrolein. Mention is made of the removal of viable spores by physical means such as by dissolving out the crystal protein from the spores, removing the spores by filtration or centrifugation followed by precipitation of the protein, and treatment with irradiation, and by use of such sporicidal agents as formaldehyde, glycidaldehyde and glutaraldehyde.ALSO:Bacterial and fungal cultures, particularly those of insecticidal protein crystal-forming bacteria such as Bacillus thuringiensis, are rendered substantially free from viable spores by treating them with an olefinically unsaturated aldehyde, particularly acrolein.  The culture is treated with the aldehyde at a concentration of less than 2000 ppm. at a temperature of approximately 30 DEG C.  Suspensions of crystal-forming bacteria so treated may be formulated with carriers, surface active agents, wetting agents and liquid or solid diluents to give baterial insecticide compositions in the form of dusts, granules, briquettes, wettable powders, pastes, solutions, suspensions, emulsions and emulsifiable concentrates.  Examples disclose the sporicidal activity of acrolein on spores of Bacillus thuringiensis, Bacillus subtilis, Aspergillus niger, Penicillium roqueforti and Alternaria brassicicola.  One comparative example demonstrates the insecticidal effect on larvae of cabbage leaves treated with (1) a spore/crystal mixture, (2) the spore/crystal mixture sterilized by treatment with acrolein for 4 hours, (3) the spore/crystal mixture autoclaved at 15 lb/sq. in. for 20 minutes and then treated with acrolein, and (4) a solution of acrolein. Mention is made of the removal of viable spores by physical means such as by dissolving out the crystal protein from the spores, removing the spores by filtration or centrifugation followed by precipitation of the protein, and treatment with irradiation, and by use of such sporicidal agents as formaldehyde, glycidaldehyde and glutaraldehyde.