Study On Transgenic Detecting Techniques For Highly Processed Products Of Main Foodcrops

Genetically modified organisms(GMO) are referred as living organisms of crop origin in which the artificial introduction of foreign genes is able to confer novel characteristics not found in the wild variety.At present,there hasn't an acknowledged GMO international standard yet,there are no unified method and standard for detection of GMO in our country either.So developing GMO analytical techniques as soon as possible would provide a precious tool for the safety assessment on GMO.They are also the important guarantees for the development of international trade in agricultural products.In this paper,GMO detecting techniques for highly processed products of soybean,maizen and rice were researched.The available methods for DNA extraction, identification analysis and quantitative detection of GMO were developed and established.We are trying to offer the foundation of fast,high-efficient and accurate GMO detecting standard method through this study.DNA recovery from food samples might be of great importance when the raw material used in the production process has to be traced.We were interested in verifying the presence of DNA in highly processed products in order to determine the foreign elements.The reliable DNA extraction method of the Wizard^? Magnetic DNA Purification System for Food Kit for highly processed product has been defined,as far as both quantity and quality are concerned,and the possibility of using this DNA for detection of thetransgenic elements of main foodcrops.A novel method of the multiplex nested PCR,was developed for the sensitive detection of several foreign genes inserted in transgenic soybean,maizen and rice(CP4-EPSPS,Cry1A(B), BAR,PAT and RBCL) in highly processed products.We detected eleven representative highly processed products samples(soya lecithin,soya protein powder,chocolate beverage,infant rice cereal,soybean refine oil,soybean salad oil,maizen oil,maizen protein powder,maizen starch, maizen jam) by the multiplex nested PCR.The first multiple PCR could not detect the insert signals in the processed products,and the sensitivity is 0.5%.However the second multiplex PCR, which could simultaneously detect CP4-EPSPS,Cry1A(B),BAR,PAT and RBCL genes with a sensitivity of 0.005%in the multiplex nested PCR.The result indicate the advanced level of this method for the detection of the genetically modified products main foodcrops.It was a flexible assay to detect the transgenic soybean,maizen and rice in highly processed products of main foodcrops.a multiple real time PCR,based on the intercalating dye SYBR Greenâ… and the analysis of the malting curves of the amplified products,was developed for the sensitive detection of several foreign genes insert in transgenic soybean,maizen and rice(CP4-EPSPS,Cry1A(B),BAR and PAT gene) in highly processed products.Using this method,different amplification products specific for the CP4-EPSPS,Cry1A(B),BAR and PAT genes were obtained and identified by their specific T_m. We have showed the suitability of the methods for identification of GMOs with a sensitivity of 0.1%in duplex reactions,0.5%in triple reactions and 1%in quadruplex reactions.A novel method of the gene array,based on the multiple PCR,was developed for the sensitive detection of several foreign genes insert in transgenic soybean,maizen and rice(CP4-EPSPS, Cry1A(B),BAR,PAT and RBCL) in highly processed products with a sensitivity of 0.25%.The transgenic soybean,maizen and rice were quantitatively detected respectively by two different real time PCR methods,i.e.SYBR Greenâ… and TaqMan,and the CP4-EPSPS,Cry1A(B), BAR and PAT gene contents in five standard samples were quantified by the two assays respectively.The results indicate that the two optimized PCR systems could be used for practical quantitative detection of the CP4-EPSPS,Cry1A(B),BAR and PAT genes in highly processed products.In this experiment,standard molecule for identification of the CP4-EPSPS,Cry1A(B),BAR and PAT genes were constructed to solve deficiency of transgenic materials.In this experiment,a series of methods have been set up and proved to be specific,highly sensitive and reliable for GMO detecting techniques for main foodcrops,which offer the foundation of standard identification analysis and quantitative detection of GMO,so it helps to provide the technique guarantees for the development of GMO labelling system.