Fat-soluble vitamins are vitamins that are insoluble in water, soluble in fat, and organic solvents; they are found in minute amount in various foods. Fat-soluble vitamins, including vitamins A, D, E, and K, have been widely used in food, cosmetics, health care products, and pharmaceutical industries. Fat-soluble vitamins are currently produced via biological and chemical synthesis. In recent years, fat-soluble vitamin production by biotechnological routes has been regarded as a very promising approach. Based on biosynthetic pathways, considerable advances of α-tocopherol and β-carotenes have been achieved in transgenic plants and microalgae. Microbial fermentation, as an alternative method for the production of vitamin K and β-carotenes, is attracting considerable attention because it is an environment friendly process. In this review, we address the function and applications of fat-soluble vitamins, and an overview of current developments in the production of fat-soluble vitamins in transgenic plants, microalgae, and microorganisms. We focus on the metabolic and process engineering strategies for improving production of fat-soluble vitamins, and we hope this review can be useful for the people who are interested in the production of fat-soluble vitamins by biotechnological routes.

中文翻译：

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脂溶性维生素生产的代谢工程：进展和观点。

脂溶性维生素是不溶于水，可溶于脂肪和有机溶剂的维生素。它们在各种食物中的含量很少。脂溶性维生素，包括维生素A，D，E和K，已广泛用于食品，化妆品，保健品和制药行业。脂溶性维生素目前是通过生物和化学合成生产的。近年来，通过生物技术途径生产脂溶性维生素被认为是非常有前途的方法。基于生物合成途径，在转基因植物和微藻中已经取得了α-生育酚和β-胡萝卜素的显着进步。微生物发酵作为生产维生素K和β-胡萝卜素的替代方法，由于它是一种环境友好的方法，因此引起了极大的关注。在这篇评论中 我们将探讨脂溶性维生素的功能和应用，并概述转基因植物，微藻类和微生物中脂溶性维生素生产的最新进展。我们专注于代谢和工艺工程策略，以改善脂溶性维生素的生产，我们希望这篇评论对那些对通过生物技术途径生产脂溶性维生素感兴趣的人们有用。