TRACE GLUCOSE ELECTRODE FOR CLINICAL, FOOD AND ENVIRONMENTAL DETERMINATIONS

International audienceA very sensitive method has been devised for the determination of glucose using electrochemical sensors. The differential device includes a glucose electrode, consisting of a platinum disk covered by a Beta-D-glucose oxidase collagen membrane, and a compensating electrode mounted with a non-enzymatic collagen membrane. Current outputs of both electrodes are substracted and differentiated giving steady-state and dynamic responses proportional to glucose concentration in the 100 nM - 2mM range. The glucose sensor has been successfully tested in clinical (human whole blood, plasma or serum and human seminal plasma), food (fruit, wines, preserved food) and environmental analysis (polluted river, whey) illustrating the high selectivity and versatility of the device

EXPERIMENTAL SIMULATION OF BIODEGRADATION IN RIVERS OXYGEN, ORGANIC MATTER AND BIOMASS CONCENTRATION CHANGES

International audienceDissolved oxygen (DO) and biochemical oxygen demand (BOD) concentration changes after an organic matter discharge into a river have been studied in the absence of oxygen transfer. According to these laboratory experiments, biodégradation of various organic compounds (glucose, glutamic acid, starch, ovalbumin and ethanol) in Seine river samples incubated at 15 30 C follow a biphasic behaviour. During a lag-phase of 10 20 h, DO decreases linearly (0.12 ppm h 1 at 20 C), whereas BOD is constant. During a subsequent aerobic exponential phase. DO and BOD uptake are proportional and increase exponentially with time (0.13 h 1 at 20 C). Using cell ATP as biomass indicator, the latter phase was shown to correspond to a cell division step. A kinetic model was developed for stimulating DO and BOD concentration changes after a waste water discharge at temperatures ranging between 15 and 30 C

Des alliances internationales pour préserver la production de soja non génétiquement modifié au Brésil : enjeux et perspectives

Catellanet Christian, Armengaud Agathe, Griot Jean-Yves, Apoteker Arnaud. Des alliances internationales pour préserver la production de soja non génétiquement modifié au Brésil : enjeux et perspectives. In: Tiers-Monde, tome 47, n°188, 2006. Biotechnologies et développement agricole, sous la direction de Marc Dufumier. pp. 755-772

Des alliances internationales pour préserver la production de soja non génétiquement modifié au Brésil : enjeux et perspectives

[fre] Après une longue période au cours de laquelle le gouvernement brésilien s’est opposé à l’emploi de soja transgénique, la culture de celui-ci a finalement été autorisée au Brésil. Les conséquences de cette autorisation peuvent ne pas être mineures, quand on sait qu’au sein de l’Union Européenne, principal débouché à l’exportation, de nombreuses associations de consommateurs et mouvements environnementalistes militent contre les importations de tout produit issu de soja génétiquement modifié. L’article relate les conditions dans lesquelles certaines organisations paysannes du Sud-Brésil et des organisations non gouvernementales européennes tentent de mettre en place des filières d’exportation de soja non transgénique vers la France. Le surcoût pour le consommateur, largement lié au coût de la traçabilité, resterait modeste. Mais les compagnies transnationales de l’agrobusiness ne restent pas sans réagir, comme en témoigne leur proposition de s’engager sur la création d’un label « soja responsable » qui prendrait en compte les risques de déforestation liés à l’extension inconsidérée du soja dans le bassin amazonien, mais accepterait les OGM . Cela paraît une manière habile de diviser la société civile en cooptant une partie des ONG environnementalistes autour de ce label « responsable », et de faire accepter finalement les OGM par l’opinion publique européenne. [eng] Following a long period of Brazilian government opposition to the use of transgenic soya, the cultivation of this latter has finally been authorized in Brazil. The consequences of this authorization may not be minor whereas it is well known that within the European Union, the principal export opportunity, numerous consumer associations and environmental movements are fighting the imports of all genetically modified soya. The article recounts the conditions in which some peasant organisations in Southern Brazil and european non governmental organisations are trying to establish export links for non transgenic soya to France. The overhead costs for the consumer, mainly incurred from ensuring tracers, remain low. However the global agro business companies are not doing nothing about this; they are committed to the creation of a « responsible soya » label that would take into account the risks of deforestation linked to the inconsiderate extension of soya in the Amazon basin, but which would still involve GMOs. This appears to be a smart way of dividing civil society through mobilising a part of the environmentalists around the « responsible » label and of finally making GMO acceptable to the European public opinion.

Des alliances internationales pour préserver la production de soja non génétiquement modifié au Brésil : enjeux et perspectives

Following a long period of Brazilian government opposition to the use of transgenic soya, the cultivation of this latter has finally been authorized in Brazil. The consequences of this authorization may not be minor whereas it is well known that within the European Union, the principal export opportunity, numerous consumer associations and environmental movements are fighting the imports of all genetically modified soya. The article recounts the conditions in which some peasant organisations in Southern Brazil and european non governmental organisations are trying to establish export links for non transgenic soya to France. The overhead costs for the consumer, mainly incurred from ensuring tracers, remain low. However the global agro business companies are not doing nothing about this ; they are committed to the creation of a « responsible soya » label that would take into account the risks of deforestation linked to the inconsiderate extension of soya in the Amazon basin, but which would still involve GMOs. This appears to be a smart way of dividing civil society through mobilising a part of the environmentalists around the « responsible » label and of finally making GMO acceptable to the European public opinion.

Les OGM : les points de vue en présence. Conférence de citoyens sur l'utilisation des organismes génétiquement modifiés.

Apoteker Arnaud, Gay Philippe, Riesel René, Marteau Didier, Guillou Marion. Les OGM : les points de vue en présence. Conférence de citoyens sur l'utilisation des organismes génétiquement modifiés.. In: Économie rurale. N°248, 1998. pp. 45-51