Análise microscópica do amido extraído de milho (Zea mays) convencional e transgênico / Microscopic analysis of the starch extracted from conventional and transgenic corn (Zea mays)

Os programas de melhoramento genético têm desenvolvido uma grande variedade de sementes de milho, com características que conferem maior resistência às adversidades do plantio, e permitem a extensão do seu cultivo nas mais diversas condições climáticas. A análise microscópica de grãos é uma ferramenta de grande relevância na caracterização das matérias primas e modificações do amido. Levando-se em conta o fato do uso de transgênicos em alimentos ser ainda controverso, e principalmente para os consumidores, o considerável aumento de sua utilização como ingrediente em produtos alimentícios, o presente trabalho investigou a possibilidade de detectar, por meio de microscopia, a variação das características dos grãos de amido de milho transgênico em comparação com os grãos de amido de milho convencional. Os resultados indicaram diferenças entre os grãos de amido extraídos de milho convencional e naqueles extraídos de milho transgênico. O amido extraído de milho convencional, em sua maioria, caracterizou-se pela presença de grânulos de formato poliédrico, alguns ligeiramente abaulados, com hilo em formato estrelado. No amido extraído dos grãos de milho transgênico, o hilo apresentou formato linear, pontual ou ausente. Estas propriedades serão úteis para caracterizá-los nos trabalhos de pesquisa e de identificação em produtos alimentícios.

The genetic programs have developed the varieties of maize seed, with features that providegreater resistance to the planting adversity, thus to carry out the extension of their cultivationat varied weather conditions. Microscopic analysis of grain is a relevant tool for characterizingthe raw materials and the starch modifications. Taking into account the fact of the use ofgenetically modified organisms (GMOs) in food being still controversial, especially for consumers, and also owing to their significant increased use as ingredients in food products, the presentstudy investigated the possibility in detecting the characteristics variations of transgenic cornstarch grains by microscopy, in comparison with the conventional corn starch grains. The results showed significant differences between the conventional starch grains-extracted maize andthose derived from transgenic maize. Conventional corn-extracted starch was characterized mostly by the presence of polyhedral shaped beads, some of them slightly cambered, with Starryformat hilum, while the extracted starch from genetically modified maize grain, the hilum showed a linear format, punctual or absent. These findings will be valuable for conducting studies and for performing food products characterization and identification.

Progress in digital PCR technology and application / 生物工程学报

Digital PCR is an emerging analysis technology for absolute quantification after realtime-PCR. Through digital PCR, single DNA molecules are distributed into isolated reactions, and the product with fluorescence signal can be detected and analyzed after amplification. With the advantages of higher sensitivity and accuracy, digital PCR, independent of a standard curve, is developing rapidly and applied widely to the next generation sequencing and detection fields, such as gene mutation, copy number variation, microorganism, and genetically modified food. In this article, we reviewed the quantitative method and research progress of digital PCR technology in the main application fields.

Información sesgada en torno a los alimentos genéticamente modificados / Informação parcial em torno dos alimentos geneticamente modificados / Biased information around genetically modified food

La actitud que el consumidor muestra frente a los alimentos genéticamente modificados (AGM) viene condicionada por el grado de conocimiento sobre ellos y la información recibida. El objetivo de este estudio es conocer el tipo de información que tiene el consumidor sobre los AGM y saber si dicha información es suficiente a la hora de optar por consumirlos o no. La metodología utilizada ha sido cuantitativa, mediante análisis descriptivos y bivariables de los datos. Los resultados obtenidos muestran que los medios de comunicación son la principal fuente de información, pero estos solo exhiben una visión sesgada sobre este tipo de alimentos. Urge implicar a todos los agentes a dar información veraz y completa, abordando todos los puntos de vista sobre el tema, con el fin de ayudar al consumidor a decidir libremente sobre su consumo.

Consumer attitudes towards genetically modified food (GMF) are conditioned by the degree of knowledge about them and the information received. The aim of this study is to know the type of information consumers have about GMF and to know whether such information is enough at the time of choosing to consume it or not. The methodology used has been quantitative by descriptive analysis and comparing variables within data. Results obtained show that media is the main source of information, but it only shows a biased view about this type of food. It is urgent to imply all stakeholders to give truthful and complete information, considering all points of view about the topic, with the aim to help the consumer to decide freely about consuming it.

A atitude que o consumidor demonstra frente aos alimentos geneticamente modificados (AGM) vem condicionada pelo grau de conhecimento sobre eles e a informação recebida. O objetivo deste estudo é conhecer o tipo de informação que tem o consumidor sobre os AGM e saber se a dita informação é suficiente na hora de optar por consumi-los ou não. A metodologia utilizada foi quantitativa, mediante análises descritivas e bivariáveis dos dados. Os resultados obtidos mostram que os meios de comunicação são a principal fonte de informação, poém estes só exibem uma visão parcial sobre este tipo de alimentos. Urge implicar todos os agentes a dar informação veraz e completa, abordando todos os pontos de vista sobre o tema, com a finalidade de ajudar o consumidor a decidir livremente sobre seu consumo.

Comparative Analysis of Immunoreactivity between Individual Serum and Pooled Serum in Serum Screening / 소아알레르기및호흡기학회지

PURPOSE: Serum screening test to detect specific immunoglobulin E (IgE) is an important step for the assessment of potential allergenicity of genetically modified (GM) food. The purpose of this study was to evaluate the usefulness of pooled serum for serum screening instead of individual serum. METHODS: Children with allergic disease were recruited and those who were sensitized to peanut or egg white were selected to obtain their sera. Sensitization to these foods was determined when the level of specific IgE was over 0.35 kU/L by ImmunoCAP. The patients were divided into subgroups according to their level of specific IgE. Raw proteins were extracted and immunoblot analysis was performed to compare the immunoreactivity between individual serum and pooled serum. RESULTS: Pooled serum from peanut-sensitized allergic children showed all the bands which were shown in immunoblot analysis by using individual serum and peanut protein extract. These findings were demonstrated both in pooled serum with low level of peanut-specific IgE and in those with high level of peanut-specific IgE. Likewise, there was no difference in the immunoreactivity between individual serum and pooled serum from egg white-sensitized allergic children. CONCLUSION: Pooled serum can be used as an alternative to individual serum for the serum screening in the allergenicity assessment of GM food.

Assessment of Allergenicity in Genetically Modified Herbicide-Resistant Foods Using the Serum Screening Test / 소아알레르기및호흡기학회지

PURPOSE: This study aimed to evaluate the potential allergenicity of genetically modified (GM) herbicide-resistant food by using the serum screenning test. METHODS: Children with allergic disease were recruited, and those who were sensitized to soybean, corn or peanut were selected to obtain their sera. Sensitization to these food allergens was determined when the level of specific IgE was over 0.35 kU/L using ImmunoCAP (Pharmacia, Uppsala, Sweden). Immunoblot analyses were performed for soybean (n=50), corn (n=50) and peanut (n=20). Newly inserted gene was sequenced and cloned from GM soy (Roundup Ready Soybean, Monsanto), GM corn (Bt 11, Syngenta) and GM canola (MS8/RF3 canola, Bayer CropScience). These proteins, such as CP4 EPSPS, PAT, and BAR, were expressed and purified for the serum screening test. RESULTS: Immunoblot analysis using CP4 EPSPS and sera from soybean-sensitized children showed no bands. Likewise, sera from corn-sensitized children and PAT did not demonstrate IgE binding in immunoblot analysis. In addition, there were no reactions between BAR and sera from peanut-sensitized patients. CONCLUSION: The serum screening test using sera from allergic children and newly inserted protein (CP4 EPSPS, PAT and BAR) in GM soybean, GM corn and GM canola failed to show IgE binding in immunoblot analysis. The results of this study suggest that these newly inserted proteins may not cause allergic disease. Further studies using more sera from allergic children are needed to conclude the safety of herbicide-resistant GM food.

Genetically modffied food crops and public health / Cultivos alimenticios genéticamente modificados y salud pública

The progress made in plant biotechnology has provided an opportunity to new food crops being developed having desirable traits for improving crop yield, reducing the use of agrochemicals and adding nutritional properties to staple crops. However, genetically modified (GM) crops have become a subject of intense debate in which opponents argue that GM crops represent a threat to individual freedom, the environment, public health and traditional economies. Despite the advances in food crop agriculture, the current world situation is still characterised by massive hunger and chronic malnutrition, representing a major public health problem. Biofortified GM crops have been considered an important and complementary strategy for delivering naturally-fortified staple foods to malnourished populations. Expert advice and public concern have led to designing strategies for assessing the potential risks involved in cultivating and consuming GM crops. The present critical review was aimed at expressing some conflicting points of view about the potential risks of GM crops for public health. It was concluded that GM food crops are no more risky than those genetically modified by conventional methods and that these GM crops might contribute towards reducing the amount of malnourished people around the world. However, all this needs to be complemented by effective political action aimed at increasing the income of people living below the poverty-line.

El progreso de la biotecnología de plantas ha hecho posible ofrecer una oportunidad para desarrollar nuevos cultivos alimenticios con características deseables para el mejoramiento de la producción, la reducción del uso de agroquímicos y la incorporación de propiedades nutricionales en cultivos básicos. No obstante, los cultivos GM se han convertido en un objeto de intenso debate, en el cual los opositores argumentan que los cultivos GM representan una amenaza para la libertad individual, el medio ambiente, la salud pública y las economías tradicionales. A pesar de los avances en la agricultura de los cultivos alimenticios, la situación actual a nivel mundial está caracterizada por una hambruna masiva y por una desnutrición crónica, lo cual constituye un importante problema de salud pública. Los cultivos GM biofortificados se han considerado como una estrategia importante y complementaria para suministrar alimentos básicos naturalmente fortificados a las poblaciones con desnutrición. Las recomendaciones de los expertos y las preocupaciones públicas han conducido al diseño de estrategias para la evaluación de los riesgos potenciales de la producción y el consumo de los cultivos GM. El objetivo de la presente revisión crítica es la exposición de algunos puntos de vista en conflicto sobre los riesgos potenciales de los cultivos GM para la salud pública. Se concluye que los cultivos alimenticios GM no son más riesgosos que aquellos modificados genéticamente con los métodos convencionales, y que estos cultivos GM podrían contribuir a la reducción de la población con desnutrición en el mundo, pero se necesita que esto sea complementado con acciones políticas efectivas dirigidas a incrementar los ingresos de la población que vive por debajo de la línea de pobreza.

Evaluation of Allergenicity to Genetically Modified Organic Foods / 소아알레르기및호흡기학회지

PURPOSES: The aim of this study was to clarify whether genetically modified organic (GMO) foods cause any allergic reactions in patients with food allergy, by means of their serum tests. In addition, it was also attempted to perform follow-up observation on targeting proteins contained in GMO food, using the serum of patients with food allergy, and to show the improvement for evaluating GMO food as allergens. METHODS: To identify the targeting proteins in GMO food and to evaluate their allergenic risks, several genes including CP4 EPSPS in genetically modified soybean, and Cry1f, Cry1Ab and Pat in genetically modified corn were cloned. The genes were transformed to synthesize proteins to induce protein expression of their target genes. The serums were divided allergy-positive and allergy-negative to soybean and corn, and SDS-PAGE and Western blotting were conducted, and finally allergenic risks were evaluated. RESULTS: This study showed that the allergenic risks of 4 targeting proteins were insignificant. Although some non-specific bands appeared, it was considered that they were not associated with allergenic risk as they often appeared in other proteins. Additionally, as a result of analyzing DNA sequences for each targeting protein with the intention of protein identification, they perfectly matched. CONCLUSION: As a way to evaluate the allergenic risk of GMO food, it is reasonable to use the purified serum proteins of allergic patients as performed in this study. However, this evaluation method is carefully applied to the future practice.

IgE sensitization to the potato allergen in adult allergy patients and identification of IgE binding components: comparison between the wild and genetically modified potato / 대한내과학회지

BACKGROUND: The aim of this study was to evaluate the prevalence of IgE sensitization and allergic risk of genetically modified (GM) potato compared with wild one in adult patients with various allergic diseases. METHODS: One thousand eight hundred eighty eight allergy patients visited Ajou University hospital and 38 healthy controls were enrolled. Skin prick tests were performed with wild and GM extracts. Phosphinothricin N-acetyltransferase (PAT) and neomycin phosphotransferase (NPT) gene was inserted in GM potato. Serum specific IgE level to the two potato extracts was measured by ELISA and their binding specificities were confirmed by ELISA inhibition test. IgE binding components in both wild and GM potato extracts were identified by SDS-PAGE and IgE-immunoblot. RESULTS: One hundred eight patients (5.7%) showed positive responses (A/H >or= 2+) on skin prick test to both wild and GM potatoes. Serum specific IgE was detectable in 50~88% among the positive reactors on skin prick test. ELISA inhibition tests showed similar inhibition pattern between wild and GM. Fourteen IgE binding components within wild potato and nine IgE binding components within GM potato with similar binding patterns, of which three major allergens in wild (26, 34, 45 kDa) and one (45 kDa) in GM one were noted.. CONCLUSIONS: The sensitization rates to wild and GM potato extracts were 5.7% respectively, in adult allergy patients and one common major allergen (45 kDa) was identified. It is speculated that genetic manipulation of the potato did not increase allergenic risk.