• Qualités nutritionnellesLes reche

• Qualités nutritionnelles
Les recherches vont dans le sens d'un développement de plantes transgéniques permettant un meilleur rendement nutritionnel et évitant l'apport de compléments nutritifs. Ainsi, il est possible d'obtenir des plantes de maïs, colza, soja à teneurs élevées en acides aminés, notamment en méthionine et lysine, et des maïs enrichis en huile. Encore, des travaux sont menés pour diminuer les propriétés allergènes du riz et du soja. On peut dire donc que la modification des gènes de certaines plantes entrant dans l'alimentation leur a conféré de nouvelles capacités.
Riz doré
Le riz est l'aliment le plus consommé au monde, et notamment en Asie. Or il existe un riz émondé (sans coque), consommé par des populations entières, qui présente une avitaminose A (carence en vitamine A). Cette avitaminose A se révèle très dangereuse, car la vitamine A étant nécessaire pour la vision, des milliers de personnes se retrouvent victimes d'une cécité partielle ou totale, et donc des troubles visuels importants et irréversibles. C'est pourquoi des recherches ont été menées sur la fabrication d'un riz beaucoup plus riche en vitamine A. L'adjonction par transgénèse de provitamine A dans l'albumen du riz émondé a en effet permis de voir naître un riz contenant suffisamment de vitamine A : le "riz doré". Ainsi, la production d'une telle O.G.M permet de prévenir des troubles de santé importants ; mais les effets à long terme de la consommation régulière de ce riz ne sont pas encore connus. Enfin, les teneurs obtenues jusqu'à présent ne fourniraient pas aux populations démunies en vitamine A, les quantités qui leur seraient nécessaires, en tous cas pas par cette seule voie. Mais, les effets de carences plus ou moins prononcés pourraient être sensiblement allégés.
Riz enrichie en fer
Selon l'Unicef, la carence en fer concernerait presque 3,7 milliards de personnes aujourd’hui dans le monde, dont la majorité est des femmes et des enfants de moins de cinq ans dans les pays en voie de développement. Ici aussi, les OGM pourraient apporter un progrès. En effet, des travaux ont permis de doubler le contenu en fer du riz en y introduisant le gène de la ferritine.
Plantes riches en acides gras spécifiques
Des recherches sont en cours sur la réduction de la teneur en acide gras mono-insaturés (graisses animales) contenues dans les huiles afin de limiter les risques cardio-vasculaires. Il s'agit d'introduire des gènes de désaturases dans les plantes oléagineuses comme le colza et le soja pour augmenter les proportions d'acides gras saturés. Ces acides gras sont les « bonnes graisses » indispensables à notre organisme.

• Maturation des fruits
Le développement de la biologie moléculaire a permis de considérer la maturation comme un événement génétiquement programmé impliquant la régulation de l’expression des gènes spécifiques. Un progrès considérable a été réalisé dans la compréhension des mécanismes de la maturation des fruits pour donner des résultats plus avancés concernant la qualité alimentaire (Gray et al., 1994 ; Lelièvre et al., 1997).
Grace à la biotechnologie on est arrivé à maîtriser l'ensemble du processus de maturation de ces fruits par manipulation génétique de l’expression des gènes correspondants.
Melon
Le melon génétiquement modifié est obtenu par un laboratoire de recherche français, en introduisant un gène antisens codant pour l’ACC oxydase, capable de bloquer la synthèse de l'éthylène, ce qui ralentit la maturation, pour un meilleur maintien de la qualité et éviter un murissement prématuré. Le détachement du fruit est retardé et le melon maintenu sur pied continue à accumuler des sucres.
Une réduction considérable de la production d’éthylène aussi bien sur pied qu'après récolte résulte en :
- une inhibition de la maturation donc une absence de jaunissement et de dégradation des chlorophylles de l’écorce,
- un ramollissement très réduit,
- absence de la formation de la zone d’abscission pédonculaire pour rester attachés à la plante,
- une production réduite d’arômes,
- la couleur de la chair, l’acidité et la teneur en sucres ne sont pas affectés.

5. Conclusions
Le génie génétique ouvre des perspectives particulièrement intéressantes pour la compréhension du vivant et l'amélioration des plantes, à condition que l'encadrement et les conditions de confinement soient suffisants.
Mais cette technologie reste une science appliquée récente, dont les principes théoriques et les outils technologiques ne sont pas aujourd’hui parfaitement maîtrisés. C’est pourquoi les plantes transgéniques doivent être appréciées au regard de leurs impacts, positifs ou négatifs, aux niveaux de l'environnement, des pratiques agricoles et de la sécurité alimentaire (tableau suivant). L’évaluation des risques des plantes transgéniques doit se faire au cas par cas, en tenant compte du transgène, l’organisme hôte, la fréquence et l’ampleur de l’introduction.

Kết quả (Anh) 1:

• Nutritional qualities
research along the lines of a development of transgenic plants for best performance nutrition and avoiding the intake of nutrient supplements. Thus, it is possible to plant corn, rapeseed, soy amino acids, including methionine and lysine, elevated and enriched corn oil. Still,. work has been conducted to reduce the rice and soybean allergenic properties. It can be said therefore that the alteration of genes of certain plants entering the food gave them new abilities.
rice golden
rice is the most consumed food in the world, and in particular in Asia. However there is a rice pruning (without shell), consumed by entire populations, which presents a vitamin A (vitamin A deficiency). This vitamin A deficiency turns out to be very dangerous, because vitamin A is necessary for vision, thousands of people find themselves victims of a partial or total blindness, and therefore important and irreversible visual disturbances. This is why research was conducted on the manufacture of a much richer in vitamin A rice. The addition by transgenesis of provitamin A in the endosperm of debarked rice has allowed of rice containing sufficient vitamin A: "golden rice". So, the production of such O.G.M to notify of important health problems; but long-term regular consumption of this rice effects are not yet known. Finally, the levels obtained so far would not provide to the poor in vitamin A, amounts that would be necessary in any case not by this single track. But, more or less pronounced deficiencies effects could be significantly alleviated.
rice enriched iron
.According to Unicef, iron deficiency would be almost 3.7 billion people today in the world, the majority are women and children under five years in developing countries. Here, too, the GMO could bring progress. Indeed, work have resulted in doubling the rice iron content by introducing the gene of the ferritin.
.Plants rich in specific fatty acids
investigations are underway on the reduction of the content of monounsaturated fatty acids (animal fats) contained in oils to reduce cardiovascular risk. This is to introduce desaturases genes into crops such as rapeseed and soybean to increase the proportions of saturated fatty acids. These fatty acids are the "good fats" necessary for our Organization.

• fruit ripening
the development of molecular biology allowed to consider maturation as a genetically programmed event involving the regulation of expression of specific genes. A considerable progress has been made in the understanding of the mechanisms of the maturation of the fruit to give more advanced results concerning food quality (Gray et al.., 1994;) Lelièvre et al., 1997).
Through biotechnology we arrived to control the whole process of maturation of these fruits by genetic manipulation of the expression of the corresponding genes.
.Melon
genetically modified melon is obtained by a french research laboratory, by introducing a gene antisense encoding ACC oxidase, able to block the synthesis of ethylene, which slows the maturation, for a better maintenance of the quality and avoid premature ripening. The detachment of the fruit is delayed and the melon maintained on foot will continue to accumulate sugars.
a considerable reduction of production of ethylene as well on foot that after harvest results in:
-inhibition of maturation so a lack of yellowing and degradation of chlorophyll from the bark,
-a very low softening,
.-lack of training of the stalk to remain attached to the plant, abscission zone
-production reduced by aromas,
-the color of the flesh, acidity and sugar content are not affected.

5. Conclusions
genetic engineering opens up exciting prospects for understanding of living and the improvement of plants, provided that the framework and conditions of confinement are sufficient.
but this technology remains a new applied science, whose theoretical principles and technology tools are now perfectly controlled. This is why transgenic plants must be assessed with regard to their impacts, positive or negative, at levels of the environment, agricultural and food security (following table) practices. The assessment of the risks of transgenic plants must be case by case, taking into account the transgene, the host, the frequency and magnitude of the introduction.
.

Kết quả (Anh) 2:

• Nutritional qualities
research going in the direction of development of transgenic plants for improved nutritional performance and avoiding the intake of nutritional supplements. Thus, it is possible to obtain plants of maize, rapeseed, soybean high in amino acids, including methionine and lysine content, and fortified corn oil. Again, work is being done to reduce the allergenic properties of rice and soybeans. We can say therefore that the modification genes from plants used in food gave them new abilities.
Golden Rice
Rice is the most consumed food in the world, particularly in Asia. But there is a rice pruned (without shell), consumed by entire populations, which has a vitamin A deficiency (VAD). This vitamin A is proving very dangerous, because vitamin A is necessary for vision, thousands of people are victims of a partial or total blindness, and therefore significant and irreversible visual impairment. This is why research has been done on making a lot more rice rich in vitamin A. The addition by transgenesis of provitamin A in the endosperm of rice pruned has made ​​it possible to see the birth of a rice containing sufficient Vitamin A: the "golden rice". Thus, the production of such GMO prevents significant health disorders; but the long-term effects of regular consumption of this rice are not yet known. Finally, the grades obtained so far do not provide vitamin A to needy populations, amounts which would be necessary, at least not in this way only. But the effects of more or less pronounced deficiencies could be significantly reduced.
rice fortified with iron
According to UNICEF, iron deficiency concern almost 3.7 billion people in the world today, the majority are women and children under five in developing countries. Again, GMOs could make progress. Indeed, work has doubled the iron content of rice by introducing the ferritin gene.
plants rich in specific fatty acids
Research is in progress on the reduction of the content of monounsaturated fatty acids (animal fats ) contained in oils to limit the cardiovascular risks. This is to introduce desaturase genes in oilseeds such as rapeseed and soybeans to increase the proportions of saturated acids. These fatty acids are essential for our body "good fats". • Ripening fruit development of molecular biology has to consider the maturation as a genetically programmed event involving the regulation of the expression of specific genes. Considerable progress has been made ​​in understanding the mechanisms of fruit ripening to give more advanced results concerning food quality (Gray et al, 1994;.. Lelièvre et al, 1997). Grace biotechnology we arrived at control the whole process of maturation of the fruit by genetic manipulation of the expression of the corresponding genes. Melon melon GM is obtained by a French research laboratory by introducing an antisense gene encoding ACC oxidase capable of block the synthesis of ethylene, which slows ripening, for a better quality maintenance and prevent premature ripening. Detachment of the fruit is delayed and melon kept up continues to accumulate sugars. Considerable reduction of ethylene production both on foot after harvest results in: - inhibition of maturation thus absence of yellowing and chlorophyll degradation bark, - a very low softening point, - the absence of the formation of abscission zone stem to remain attached to the plant, - a reduced flavor production - the flesh color, the acidity and sugar content are not affected. 5. Conclusions The genetic engineering opens particularly interesting perspectives for the understanding of living and plant breeding, provided that the supervision and containment conditions are sufficient. But this technology is recently applied science, whose theoretical principles and technological tools today are not perfectly controlled. That is why the transgenic plants must be assessed in terms of their impacts, positive or negative, levels of environmental, agricultural practices and food safety (table below). The risk assessment of transgenic plants should be on a case by case basis, taking account of the transgene, the host organism, the frequency and magnitude of the introduction.

Kết quả (Anh) 3:

• Nutritional Qualities
The research will in the sense of a development of transgenic plants for a better nutritional performance and avoiding the contribution of nutrient supplements. Thus, it is possible to obtain the plants of maize, rapeseed, soybean to elevated levels of amino acids, particularly methionine and lysine, and but enriched in oil. Still,Work is being undertaken to reduce the allergenic properties of rice and soybeans. We can say therefore that the modification of the genes of some plants entering the power conferred upon them a new capacity.
Golden Rice
Rice is the staple food the most consumed in the world, and particularly in Asia. However, there is a rice cleanse (without shell), consumed by whole populations,Which presents a vitamin A (vitamin A deficiency). This vitamin A is very dangerous, because vitamin A is necessary for the vision, thousands of people find themselves victims of a partial blindness or total, and therefore visual disturbances important and irreversible.That is why research has been conducted on the manufacture of a rice much more rich in vitamin A. The addition by transgenesis of provitamin A in the endosperm of rice cleanse has in effect allowed us to see an unborn rice containing sufficient vitamin A: the "golden rice". Thus, the production of such a O. G. M allows you to prevent significant health disorders ;But the long-term effects of regular consumption of this rice are not yet known. Finally, the concentrations obtained so far do not provide the destitute populations in vitamin A, the quantities which they would be required, in all cases not by this single track. But, the effects of deficiencies more or less pronounced could be significantly alleviated.
rice enriched with iron
According to UNICEF, of the iron deficiency would affect almost 3.7 billion people in the world today, the majority of which is women and children of less than five years in the developing countries. Here also, the GMOS could make a progress. In effect, the work has helped to double the iron content of the rice by introducing the gene for the ferritin.
Plants rich in fatty acids specific
research is currently underway on the reduction of the content in fatty acid mono-unsaturated fats (animal fat) contained in the oils in order to limit the cardiovascular risks. It is to introduce genes for desaturases in oilseed plants such as rapeseed and soybeans to increase the proportions of saturated fatty acids.These fatty acids are the "good fats" indispensable to our body.

"maturation of the fruit
The development of molecular biology has allowed us to consider the maturation as an event genetically program involving the regulation of the expression of specific genes.Considerable progress has been achieved in the understanding of the mechanisms of the maturation of the fruit to give results more advances relating to food quality (Gray et al. , 1994 ; Leliã¨vre et al. , 1997).
Grace to biotechnology it has managed to master the whole process of maturation of these fruits by genetic manipulation of the expression of the corresponding genes.
Melon
The melon genetically modified is obtained by a research laboratory french, by introducing a gene antisense coding for the ACC oxidase, capable of blocking the synthesis of ethylene, which slows the maturation, for a better maintenance of the quality and avoid a murissement premature.The secondment of the fruit is delayed and the melon maintained on foot continued to accumulate sugars.
a considerable reduction of the ethylene production as well on foot only after harvest results in :
- inhibition of the maturation therefore an absence of yellowing and degradation of chlorophylls from the bark,
- a softening very reduced,
- Absence of the formation of the zone of abscission stemless to remain attached to the plant,
- a reduced production of flavorings,
- the color of the flesh, the acidity and sugar content are not affected.

5. Conclusions
genetic engineering opens perspectives particularly interesting for the understanding of the living and the improvement of plants,On condition that the mentoring and containment conditions are sufficient.
but this technology remains an applied science recent, whose theoretical principles and the technological tools are not today perfectly controlled. That is why transgenic plants must be assessed in the light of their impacts, positive or negative, to the levels of the environment,Agricultural practices and food security (following table). The risk assessment of transgenic plants must be made on a case by case basis, taking into account of the transgene, the host agency, the frequency and magnitude of the introduction.