Method for visually detecting genetically modified foods

Abstract

The invention discloses a method for visually detecting genetically modified foods, and belongs to the field of food safety. The method is characterized in that the genetically modified foods are treated as detecting objects, and the genome DNA of the genetically modified foods is extracted; a special CaMV 35S nucleic acid probe capable of specifically recognizing the genetically modified foods and a corresponding template sequence are designed; a sequence complementation template sequence is combined to form a ring in the presence of a specific CaMV 35S promoter; the rolling circle amplification reaction is triggered under the effects of T4-DNA ligase and phi 29 polymerase; G-four chain body in the amplification product is combined with oxidized heme to generate DNA enzyme for catalyzingABTS developing, thus visually detecting the genetically modified foods. With the adoption of the method, the promoter CaMV 35S is visually detected in the genetically modified foods; the method has the advantages of being simple to operate, and visually detecting; and the method is applicable to detection of genetically modified soybean, corn, tomato and other genetically modified foods containing the CaMV 35S promoter genes.

Description

technical field [0001] The invention relates to a method for visually detecting genetically modified food, which belongs to the field of food safety. Background technique [0002] Genetically modified organisms have certain advantages in the field of agriculture due to their resistance to herbicides, insects, viruses, etc., as well as high yield and high nutritional content. And the global planting area of ​​genetically modified crops increased from 17,000 hectares in 1996 to 1.797 million hectares in 2015. Soybean is one of the important protein sources for food and feed. With the development, genetically modified soybeans, as a major genetically modified food, have played a vital role in alleviating poverty and alleviating hunger. At the same time, the safety and impact of GM soybeans on the environment and health are still controversial. Many countries such as the European Union, South Korea, Japan and Australia require soy to be analyzed to ensure strict adherence to ...

AI Technical Summary

Problems solved by technology

In the Investigation of the use of rolling circle amplification for the detection of GM food, the RCA method is used to detect genetically modified foods, and gel electrophoresis is used to qualitatively analyze the results, which has the problem of insufficient detection accuracy

(2) Hao Zhenming, Zhao Xin, Wu Xiaohuai and other hyperbranched rolling circle amplification technology combined with test paper method to detect various genetically modified components in food, the detection limit is 100pg / uL, there are problems of insufficient detection accuracy and high detection limit ; (3) Guven B, Boyaci I H, Tamer U et al. in Development of rolling circle amplification based surface-enhanced Raman spectroscopy method for 35Spromoter gene detection, reported the use of modified gold nanorods combined with RCA reaction to detect 35S through surface-enhanced Raman spectroscopy DNA method, detection range 1.0×10 -13 -1.0×10 -7 mol / L, the detection limit is 6.3×10 -15 mol / L, the detection process needs to synthesize and modify gold nanoparticles and gold nanorods, the experimental method is cumbersome, and the detection requires the use of surface-enhanced Raman equipment, and the detection method is expensive; (4) Wang X, Da T, Guan Q et al. reported in Detection of genetically modified crops using multiplex asymmetric polymerasechain reaction and asymmetric hyperbranched rolling circle amplification coupled with reverse dot blot that multiplex PCR combined with multi-branched RCA was used to detect transgenic crops by dot hybridization, and the detection limit was 0.1ug / L 2% RRS and 0.5ng / L transgenic soybean DNA, but it needs to be used in conjunction with multiple PCR instruments, which increases the complexity of the detection method, and there are problems such as long experiment time and low sensitivity of experimental results by dot hybridization display method

G-quadruplex DNAbiosensor forsensitive visible detection of genetically modified food. Using G-quadruplex to form DNase display reaction to detect genetically modified food, the detection range is 5.0×10 -8 -5.0×10 -7 mol / L, detection limit 3.0×10 -9 mol / L, there is a problem of small detection range and high detection limit

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