This review provides an overview of the current status of the chemistry and biology of di-D-fructose dianhydrides (DFAs) with a focus on their potential as functional foods. The history of this family of cyclic ketodisaccharides has expanded for almost 100 years and offers a paradigmatic example of artificial synthetic molecules that were identified as natural products later on and finally encountered in our own table. Issued from fundamental investigations on the reactivity of carbohydrates in strongly acidic media, DFAs remained laboratory curiosities for decades. Early reports on their isolation from plants raised doubts, until the formation of some DFA representatives by the action of microorganisms on fructans was reported in the middle 1980s. Since then, research on DFAs has run in parallel in the areas of microbiology and carbohydrate chemistry. Evidence of the potential of these compounds as functional food was accumulated from both sides, with the development of biotechnological processes for mass production of selected candidates and of chemical methodologies to prepare DFA-enriched products from sucrose or inulin. In 1994 a decisive discovery in the field took place in the laboratory of Jacques Defaye in Grenoble, France: the presence of DFAs in a commercial sucrose caramel was evidenced in a quite significant 18% mass proportion! The development of an efficient analytical protocol for DFAs and the stereoselective synthesis of individual standards allowed one to demonstrate that DFAs and their glycosylated derivatives (glycosyl-DFAs) are universally formed during caramelization reactions. They are not potential food products; they have actually always been in our daily food. Most important, they seem to exert beneficial effects: they are acariogenic, low-caloric, and promote the growth of beneficial microflora in the gut. Most recent evidence indicates that DFAs can even protect the intestinal tract against agressive agents favor the assimilation of antioxidants, and act as a drug-like food for the treatment of colon ailments such as inflammatory bowel disease (Crohn disease). The development of efficient methodologies for the preparation of DFA-enriched caramels, compatible with the food and agricultural industry regulations, may lead to new natural functional foods and nutraceuticals based on DFAs in the near future.

中文翻译：

---

双果糖二酐（DFA）和富含DFA的产品作为功能食品。

本文对二-D-果糖二酐（DFA）的化学和生物学现状进行了概述，重点介绍了其作为功能食品的潜力。该环状酮二糖家族的历史已有近100年的历史，提供了人工合成分子的典范实例，这些分子后来被鉴定为天然产物，并最终在我们自己的餐桌上遇到。DFA源自对强酸性介质中碳水化合物反应性的基础研究，数十年来一直是实验室的好奇心。关于它们与植物分离的早期报道引起了人们的怀疑，直到1980年代中期，有人报道了微生物对果聚糖的作用形成了一些DFA代表。自那以后，DFA的研究在微生物学和碳水化合物化学领域并行进行。双方都积累了这些化合物作为功能性食品的潜力的证据，同时还发展了用于批量生产选定候选物的生物技术工艺和从蔗糖或菊粉制备富含DFA的产品的化学方法。1994年，在法国格勒诺布尔的雅克·迪法耶（Jacques Defaye）的实验室中进行了决定性的发现：商用蔗糖焦糖中DFA的含量非常高，为18％！对DFA的高效分析规程的开发和各个标准品的立体选择性合成，使人们能够证明DFA及其糖基化衍生物（糖基-DFA）是在焦糖化反应过程中普遍形成的。它们不是潜在的食品；他们实际上一直是我们的日常饮食。最重要的是，它们似乎发挥了有益的作用：它们具有诱因性，低热量，并促进肠道有益菌群的生长。最新的证据表明，DFA甚至可以保护肠道免受侵害剂的侵害，有利于抗氧化剂的同化，并且可以作为类药物的食物来治疗结肠疾病，例如炎症性肠病（克罗恩病）。与食品和农业行业法规兼容的高效的制备富含DFA的焦糖的方法学的发展，可能会导致在不久的将来基于DFA的新型天然功能食品和保健食品。它们似乎发挥了有益的作用：它们是成因的，低热量的，并促进肠道有益菌群的生长。最新的证据表明，DFA甚至可以保护肠道免受侵害剂的侵害，有利于抗氧化剂的同化，并且可以作为类药物的食物来治疗结肠疾病，例如炎症性肠病（克罗恩病）。与食品和农业行业法规兼容的高效的制备富含DFA的焦糖的方法学的发展，可能会导致在不久的将来基于DFA的新型天然功能食品和保健食品。它们似乎发挥了有益的作用：它们是成因的，低热量的，并促进肠道有益菌群的生长。最新的证据表明，DFA甚至可以保护肠道免受侵害剂的侵害，有利于抗氧化剂的同化，并且可以作为类药物的食物来治疗结肠疾病，例如炎症性肠病（克罗恩病）。与食品和农业行业法规兼容的高效的制备富含DFA的焦糖的方法学的发展，可能会导致在不久的将来基于DFA的新型天然功能食品和保健食品。最新的证据表明，DFA甚至可以保护肠道免受侵害剂的侵害，有利于抗氧化剂的同化，并且可以作为类药物的食物来治疗结肠疾病，例如炎症性肠病（克罗恩病）。与食品和农业行业法规兼容的高效的制备富含DFA的焦糖的方法学的发展，可能会导致在不久的将来基于DFA的新型天然功能食品和保健食品。最新的证据表明，DFA甚至可以保护肠道免受侵害性物质的侵害，这些物质有利于抗氧化剂的同化，并且可以作为类药物的食物来治疗结肠疾病，例如炎症性肠病（克罗恩病）。与食品和农业行业法规兼容的高效的制备富含DFA的焦糖的方法学的发展，可能会导致在不久的将来基于DFA的新型天然功能食品和保健食品。