美国研究人员:转基因玉米增加营养价值

编辑:给力英语新闻 更新:2017年10月12日 作者:美国之音(VOA News)

内布拉斯加州弗里蒙特的一处玉米地(资料照)
内布拉斯加州弗里蒙特的一处玉米地(资料照)

美国研究人员本星期说,他们发现了一种改造玉米基因的方式,可以生产出肉类所含有的氨基酸。玉米是世界上数量最多的大宗农作物。

这种基因改造的结果是产生出营养丰富的食品,可以造福全世界千百万人,同时还能减少动物饲料成本。同行审议刊物《国家科学院院刊》发表的一份报告宣布了这一突破。

研究人员说,转基因过程涉及把玉米与某种细菌相结合,以产生出蛋氨酸,这是一种通常只在肉类中发现的氨基酸。

罗格斯大学植物生物学系教授、研究报告的共同作者托马斯·劳斯特克(Thomas Leustek)对美国之音说:“我们改善了玉米的营养价值。这是地球上种植的最大宗的作物。多数玉米都用于动物饲料,但它缺乏蛋氨酸,这是一种关键的氨基酸,而我们发现了一种加入蛋氨酸的有效方式。“

新的方式是向玉米杆的基因组中加入大肠杆菌,这随后会导致玉米杆的叶子产生蛋氨酸。根据这项研究,玉米粒中的蛋氨酸随后增加了大约57%。

研究报告的共同作者乔奇姆·梅辛(Joachim Messing)说,科研人员在罗格斯大学用这种转基因玉米喂鸡,以显示其对鸡的营养价值。

报告作者在新闻稿中说,通常情况下,鸡饲料是用玉米和大豆混合制成的,但这种混合饲料缺乏蛋氨酸。

梅辛说:“添加蛋氨酸是因为没有它动物就无法生长。在许多发展中国家,玉米是主食,蛋氨酸对人类、特别是孩子,也很重要。它是关键的营养成份,和维生素一样。”

劳斯特克说,如果可以成功推广使用这种转基因玉米,发展中国家的民众“就不必购买蛋氨酸补充剂或者蛋氨酸含量更高的昂贵食品。”

US Researchers Genetically Modify Corn to Boost Nutritional Value

U.S. researchers said this week they have discovered a way to genetically engineer corn, the world's largest commodity crop, to produce a type of amino acid found in meat.

The result is a nutritionally rich food that could benefit millions worldwide, while also reducing the cost of animal feed. The breakthrough came in a report in the National Academy of Sciences, a peer-reviewed journal.

Researchers say the process involves infusing corn with a certain type of bacteria in order to produce methionine, an amino acid generally found in meat.

"We improved the nutritional value of corn, the largest commodity crop grown on Earth," Thomas Leustek, professor in the Department of Plant Biology at Rutgers University and co-author of the study, told VOA. "Most corn is used for animal feed, but it lacks methionine -- a key amino acid -- and we found an effective way to add it."

The new method works by adding an E. coli bacteria into the genome of the corn plant, which then causes the methionine production in the plants leaves. According to the study, methionine in the corn kernels then increases by about 57 percent.

The scientists fed the genetically modified corn to chickens at Rutgers University in order to show it was nutritious for them, co-author Joachim Messing said.

Normally, chicken feed is prepared as a corn-soybean mixture, the authors said in a press release, but the mixture lacks methionine.

"Methionine is added because animals won't grow without it. In many developing countries where corn is a staple, methionine is also important for people, especially children. It's vital nutrition, like a vitamin,” Messing said.

If the genetically modified corn can be successfully deployed, those who live in developing countries “wouldn't have to purchase methionine supplements or expensive foods that have higher methionine," Leustek said.

Victor Beattie contributed to this report.