2011-01-012024-05-15https://scholars.lib.ntu.edu.tw/handle/123456789/662337摘要：建立基改作物食品安全性的評估以及非預期效應之平台，是推動國內基因改造作物商品化之當務之急。基因改造食品的非預期效應通常包括食品本身的安全性、種植基改作物對環境的衝擊，以及產品本身的性質三方面。世界蔬菜中心(即前稱亞蔬中心)已開發出第二代抗胡瓜嵌紋病毒基改番茄，此第二代基改番茄對胡瓜嵌紋病毒之抗病性可達 100%，可減少番茄生產因病毒與真菌感染所造成之損失，耐熱性高並且抗萎凋病及青枯病之多抗非停心型櫻桃番茄，使產量提昇15~20 %，更可減少農藥之使用量，增加農民之收益與每年之生產經濟效益。對消費者而言，消費者亦可吃到清潔安全的新鮮番茄。另一方面，目前該基改番茄已完成環境影響評估中，轉殖基因轉移至其他近緣野生種的可能性評估，並不會轉殖至其他近緣作物之中。由於該基改番茄之生理及抗病性狀良好，產量豐富，非常具有推廣使用之潛在價值，因此世蔬中心計畫未來將於南亞、中亞多國推廣利用。本計畫擬以兩年時間，以此世蔬中心所開發之第二代基改番茄為材料，評估其安全性及非預期效應。內容包括國產基因改造蕃茄果實對沙門氏菌回復突變致變異性之 Ames 試驗以及大鼠口服急毒性試驗 2. 分析第二代基改番茄及非基改番茄加工製品之理化性質等同性 3.分析第二代基改蕃茄之寒害臨界溫度及寒害徵狀影響。<br> Abstract: Tomato is one of the most typical climacteric horticulture crops, which means there are dramatic changes in physiology between before and after mature. Therefore, evaluation of unexpected effects on the post-harvest and processing properties of genetically modified tomato is necessary. In this study, we have evaluated the safety and unexpected effects of a newly developed genetically modified (GM) tomato (variety 620), which is established by World Vegetable Center (AVRDC) with heat tolerant and multi diseases resistant properties. This study will establish a typical model for the evaluation of unexpected effects of climacteric GM fruits in their post-harvest stages, and the results will be helpful to the understanding of the ripening physiology, unexpected effects, safety and commercial utilization of GM foods. In the safety evaluation, three approaches for genetic safety were conducted by following the DOH guidelines, including in vitro gene mutation in bacteria (Ames test), chromosomal aberration test and in vivo micronuclear assay in mice. Results revealed that both non-GM and GM tomatoes fruits were negative in genotoxicity. The acute oral toxicity and 28-day feeding toxicity in rats were performed in the GM (620) or non-GM 1558 tomato fruits in rats. Rats were conducted to gavage single dose 5 g/kg bw, and showed the level of oral LD50 of GM (620) or non-GM 1558 tomato fruits is greater trhan 5 g/kg bw in rats. Furthermore, the low-dose (1 g/kg) and high-dose (2 g/kg) of GM (620) or non-GM 1558 tomato fruits were also gavaged consecutively for 28 days in rats. Results revealed that both GM (620) or non-GM 1558 tomato fruits caused slight to significant decreases of feed consumption and body weight gains in the high dose groups at the end of experiment. No significant changes of hematology, biochemistry, and pathology data and suggested that decreases of feed consumption and body weight gains might be related to nutritional imbalance of energy. However, the mechanisms need to elucidate in the future. In conclusion, the food safety of GM (620) and non-GM 1558 tomato fruits are substantial equivalent in rats.To evaluate the post-harvest responses of GM tomatoes, standard protocols used in the evaluation of post-harvest response of typical climate horticulture crops shall be adapted including the evaluation of respiration and ethylene production rate, natural and artificial ripening pressure, composition analysis of various processing products, etc. The experimental results gave the following investigations, (1) the cultivation growth of GM (620) tomato showed capable in naturally ripening. (2) Under 100 ppm ethylene treatment for forced ripening, GM (620) tomatoes showed a similar ethylene and carbon dioxide producing capability (p > 0.05), compared to non-GM 1558 tomato fruits. (3) All the postharvest related genes showed a normal expression within GM 620 tomatoes. (4) The total reducing sugar content and total acid content within GM 620 tomatos are similar to those of the control tomatoes. (5) GM 620 tomatoes showed similar responses to chilling injury. (6) The color changes of GM 620 tomatoes during ripening showed no significant difference to the non-GM 1558 tomatoes. These results indicated that the post-harvest responses and physiology of GM (620) and non-GM 1558 tomato fruits are substantial equivalent. To evaluate the substantial equivalence in chemical compositions of GM tomatoes, their basic nutrients, including carbohydrate, fatty acid, amino acid, mineral elements, vitamins and other items, were analyzed and determined. The results demonstrated that GM (620) tomatoes have similar physical and chemical characteristics to the non-GM 1558 tomatoes. The differences between GM (620) and non-GM 1558 tomatoes were lowered than 20 % in their moisture content, ash content, crude proteins, crude lipid content, dietary fiber content, levels of soluble solids, pH value, levels of titratable acids, levels of reducing sugars, content of ascorbic acids (Vit. C) and tocopherols (Vit. E), which could be resulted from common cultivation and individual variations between fruits. These results suggested that the chemical compositions of GM 620 and non-GM 1558 tomatoes were substantial equivalent.The physical and chemical characteristics of tomato pulp, puree and juice after 21 days cold storage have been investigated. The results demonstrated that the pulp, puree and juice made from GM (620) tomatoes have similar moisture content, ash content, soluble content, pH value and viscosity to those of non-GM 1558 tomatoes. There was no significant increase and decrease in these events during 21 days cold storage. However, the level of total titratable acids from GM (620) tomatoes was lower to that of non-GM 1558 puree and juice. In conclusion, the GM (620) tomatoes showed no unexpected effects on their safety evaluation, post-harvest physiology and response studies, chemical characteristics and storage changes investigation. These results could contribute to the extension and utilization of the GM (620) tomatoes with heat tolerant and multi diseases resistant properties, to developing countries and other Asia and Africa areas.基因改造番茄生物安全非預期效應