欧盟评估转基因乳酸克鲁维酵母菌株CHY生产的凝乳酶的安全性

 　　  2022年8月8日，欧盟食品安全局就一种凝乳酶（chymosin）的安全性评价发布意见。 
　　据了解，这种食品酶是由转基因乳酸克鲁维酵母菌株CHY生产的，旨在用于奶酪生产和发酵乳制品生产的牛奶加工中。
 
　　经过评估，专家小组认为，在预期的使用条件下，不能排除饮食暴露引起过敏和诱发反应的风险，特别是对雪松花粉过敏原过敏的个体。根据所提供的数据，评估小组得出结论，这种食品酶在预期使用条件下不会引起安全问题。部分原文报道如下：
 
　　The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Kluyveromyces lactis strain CHY by DSM Food Specialties B.V. It is intended to be used in milk processing for cheese production and for production of fermented milk products. Dietary exposure was estimated to be up to 0.69 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. The production strain contains multiple copies of known antimicrobial resistance genes and consequently, it does not fully fulfil the requirements for the qualified presumption of safety (QPS) approach to safety assessment. However, considering the absence of viable cells and DNA from the production organism in the food enzyme, this is not considered to be a risk. As no other concerns arising from the microbial source and its subsequent genetic modification or from the manufacturing process have been identified, the Panel considered that toxicological tests were not needed for the assessment of this food enzyme. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and four matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure, although unlikely, cannot be excluded, particularly for individuals sensitised to cedar pollen allergens. based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.