Abstract The normal development and maintenance of central neural functions are highly correlated with the amount of docosahexaenoic acid (DHA; ω-3 fatty acid) accumulated in the brain. DHA incorporated at the sn-2 position of lipids is well absorbed by intestinal mucosa and utilized efficiently in vivo. However, modern consumers have a reduced direct intake of DHA and increased intake of saturated fats or ω-6 fatty acid oils, resulting in behavioral and neurophysiological deficits. To provide an understanding of the integrated beneficial effects of DHA on the human brain, this review introduces the positional difference (sn-2 and sn-1,3 positions) of DHA on a glycerol skeleton in natural fats and oils, and further discusses the possible functional mechanism regarding DHA supplementation and the gut-brain axis. The multiple bidirectional routes in this axis offer a novel insight into the interaction between DHA supplementation, the gut microbiota, and brain health. To achieve high sn-2 DHA in diets, it is suggested that sn-2 DHA lipids be enzymatically produced in more efficient and economical ways by improving the specific activities of lipases and optimizing the purification procedures. These types of diets will benefit individuals with strong needs for sn-2 ω-3 lipids such as infants, children, and pregnant and lactating women.

中文翻译：

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对大脑有益的高 Sn-2 二十二碳六烯酸脂质及其酶合成：综述

摘要 中枢神经功能的正常发育和维持与大脑中二十二碳六烯酸（DHA；ω-3 脂肪酸）的积累量高度相关。在脂质的sn-2位置掺入的DHA被肠粘膜良好吸收并在体内有效利用。然而，现代消费者的 DHA 直接摄入量减少，饱和脂肪或 ω-6 脂肪酸油的摄入量增加，导致行为和神经生理缺陷。为了了解 DHA 对人脑的综合有益作用，本综述介绍了 DHA 在天然油脂中甘油骨架上的位置差异（sn-2 和 sn-1,3 位置），并进一步讨论了关于 DHA 补充和肠脑轴的可能功能机制。该轴上的多条双向路径提供了对 DHA 补充剂、肠道微生物群和大脑健康之间相互作用的新见解。为了在饮食中实现高 sn-2 DHA，建议通过提高脂肪酶的比活性和优化纯化程序以更有效和经济的方式酶法生产 sn-2 DHA 脂质。这些类型的饮食将有益于对 sn-2 ω-3 脂质有强烈需求的个体，例如婴儿、儿童、孕妇和哺乳期妇女。建议通过提高脂肪酶的比活性和优化纯化程序，以更有效和经济的方式酶促生产 sn-2 DHA 脂质。这些类型的饮食将有益于对 sn-2 ω-3 脂质有强烈需求的个体，例如婴儿、儿童、孕妇和哺乳期妇女。建议通过提高脂肪酶的比活性和优化纯化程序，以更有效和经济的方式酶促生产 sn-2 DHA 脂质。这些类型的饮食将有益于对 sn-2 ω-3 脂质有强烈需求的个体，例如婴儿、儿童、孕妇和哺乳期妇女。