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    【题目】下列关于胡萝卜素的叙述，错误的是（ ）

    A．胡萝卜素可用于治疗幼儿生长发育不良、干皮症等

    B．胡萝卜素可从大面积养殖的岩藻中提取

    C．萃取过程中要采用水浴加热

    D．提取胡萝卜素时，可采用石油醚、苯、丙酮等作溶剂

    【答案】D

    【解析】胡萝卜素可以用来治疗因缺乏维生素A而引起的各种疾病，如夜盲症、幼儿生长发育不良、干皮症等；工业生产上，提取天然β—胡萝卜素的方法主要有三种，一是从植物中提取，二是从大面积养殖的岩藻中获得，三是利用微生物的发酵生产；萃取过程中需要避免明火加热，采用水浴加热，这是因为有机溶剂是易燃物，直接使用明火加热容易引起燃烧；提取胡萝卜素时，对于溶剂的要求为具较高沸点、能够充分溶解胡萝卜素且不与水混溶，此外还要考虑萃取效率、对人的毒性等，由于苯和丙酮均对人体有害。综上所述，石油醚是理想的溶剂。故D正确。

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