在巴西已经开发了表达Cry1Ab的昆虫保护的甘蔗。对贸易信息的分析表明,巴西出口的所有甘蔗实际上都是原糖或精制糖和乙醇。原糖和精制糖是高度纯化的食品成分,没有检测到的转基因蛋白,提供了一个关于广义安全评估方法的有趣案例研究。在这项研究中,Cry1Ab的理论蛋白质摄入量和安全性评估,Cry1Ac,NPTII,并检查了昆虫保护生物技术作物中使用的Bar蛋白。使用八个不同且具有代表性的巴西原糖和精制糖出口市场的平均添加糖摄入量的当地市场研究数据,检查了这些蛋白质的潜在消费量(巴西,加拿大,中国,印度尼西亚,印度,Japan,俄罗斯,和美国)。平均糖摄入量,范围从5.1g添加糖/人/天(印度)到126g糖/p/天(美国)用于计算可能的人类暴露。理论蛋白质摄入量估计是在“最坏情况”的情况下进行的,假设检测到1μg新表达的蛋白质/g原糖或精制糖;“合理情况”假设1ng蛋白质/g糖。“最坏的情况”情景是基于对巴西甘蔗加工的详细研究结果,该研究表明精制糖含有少于1μg总植物蛋白/g精制糖。“合理情况”方案是基于新表达蛋白在茎中的表达水平低于总茎蛋白的0.1%的假设。使用这些从糖消耗中计算出的蛋白质摄入量,连同四种代表性蛋白质的公认NOAEL水平,我们得出结论,“最坏情况”方案的安全范围为6.9×105至5.9×107,“合理情况”方案的安全范围为6.9×108至5.9×1010。由于这些无毒蛋白质的极低可能暴露和高NOAEL,这些安全裕度非常高。这种对高纯度食品成分(如糖)进行安全评估的通用方法表明,由巴西转基因品种加工而成的糖在全球代表性市场上是安全的。
Insect-protected sugarcane that expresses Cry1Ab has been developed in Brazil. Analysis of trade information has shown that effectively all the sugarcane-derived Brazilian exports are raw or refined sugar and ethanol. The fact that raw and refined sugar are highly purified food ingredients, with no detectable transgenic protein, provides an interesting
case study of a generalized safety assessment approach. In this study, both the theoretical protein intakes and safety assessments of Cry1Ab, Cry1Ac, NPTII, and Bar proteins used in insect-protected biotechnology crops were examined. The potential consumption of these proteins was examined using local market research data of average added sugar intakes in eight diverse and representative Brazilian raw and refined sugar export markets (Brazil, Canada, China, Indonesia, India, Japan, Russia, and the USA). The average
sugar intakes, which ranged from 5.1 g of added
sugar/person/day (India) to 126 g
sugar/p/day (USA) were used to calculated possible human exposure. The theoretical protein intake estimates were carried out in the \"Worst-
case\" scenario, assumed that 1 μg of newly-expressed protein is detected/g of raw or refined
sugar; and the \"Reasonable-
case\" scenario assumed 1 ng protein/g
sugar. The \"Worst-case\" scenario was based on results of detailed studies of sugarcane processing in Brazil that showed that refined sugar contains less than 1 μg of total plant protein /g refined sugar. The \"Reasonable-case\" scenario was based on assumption that the expression levels in stalk of newly-expressed proteins were less than 0.1% of total stalk protein. Using these calculated protein intake values from the consumption of sugar, along with the accepted NOAEL levels of the four representative proteins we concluded that safety margins for the \"Worst-case\" scenario ranged from 6.9 × 105 to 5.9 × 107 and for the \"Reasonable-case\" scenario ranged from 6.9 × 108 to 5.9 × 1010. These safety margins are very high due to the extremely low possible exposures and the high NOAELs for these non-toxic proteins. This generalized approach to the safety assessment of highly purified food ingredients like sugar illustrates that sugar processed from Brazilian GM varieties are safe for consumption in representative markets globally.