title: Application of Box-Behnken experimental design to optimize the extraction of insecticidal Cry1Ac from soil.
abstract: A validated method for analyzing Cry proteins is a premise to study the fate and ecological effects of contaminants associated with genetically engineered Bacillus thuringiensis crops. The current study has optimized the extraction method to analyze Cry1Ac protein in soil using a response surface methodology with a three-level-three-factor Box-Behnken experimental design (BBD). The optimum extraction conditions were at 21 °C and 630 rpm for 2 h. Regression analysis showed a good fit of the experimental data to the second-order polynomial model with a coefficient of determination of 0.96. The method was sensitive and precise with a method detection limit of 0.8 ng/g dry weight and relative standard deviations at 7.3%. Finally, the established method was applied for analyzing Cry1Ac protein residues in field-collected soil samples. Trace amounts of Cry1Ac protein were detected in the soils where transgenic crops have been planted for 8 and 12 years.
authors: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, Peoples' Republic of China.
authors: Yan-Liang
authors: YL
authors: Li
authors: Zhi-Xiang
authors: ZX
authors: Fang
authors: Jing
authors: J
authors: You
mesh_terms: D001413:Bacillus thuringiensis; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D018556:Crops, Agricultural / Q000382:microbiology; D004731:Endotoxins / Q000737:chemistry / Q000302:isolation & purification*; D006460:Hemolysin Proteins / Q000737:chemistry / Q000302:isolation & purification*; D007306:Insecticides / Q000737:chemistry / Q000302:isolation & purification*; D017711:Nonlinear Dynamics; D030821:Plants, Genetically Modified / Q000382:microbiology; D015203:Reproducibility of Results; D012107:Research Design; D012988:Soil Microbiology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis