STABILITY OF FOOD ALLERGENS TO DIGESTION IN-VITRO

An integral part of the safety assessment of genetically modified plan ts is consideration of possible human health effects, especially food allergy. prospective testing for allergenicity of proteins obtained fr om sources with no prior history of causing allergy has been difficult because of the absence of valid methods and models. Food allergens ma y share physicochemical properties that distinguish them from nonaller gens, properties that may be used as a tool to predict the inherent al lergenicity of proteins newly introduced into the food supply by genet ic engineering. One candidate property is stability to digestion. We h ave systematically evaluated the stability of food allergens that are active via the gastrointestinal tract in a simple model of gastric dig estion, emphasizing the major allergens of plant-derived foods such as legumes (peanuts and soybean). Important food allergens were stable t o digestion in the gastric model (simulated gastric fluid). For exampl e, soybean beta-conglycinin was stable for 60 min. In contrast, nonall ergenic food proteins, such as spinach ribulose bis-phosphate carboxyl ase/oxygenase, were digested in simulated gastric fluid within 15 sec. The data are consistent with the hypothesis that food allergens must exhibit sufficient gastric stability to reach the intestinal mucosa wh ere absorption and sensitization (development of atopy) can occur. Thu s, the stability to digestion is a significant and valid parameter tha t distinguishes food allergens from nonallergens.