Chemistry, gelation, and enzymatic modification of seaweed food hydrocolloids
Chemistry, gelation, and enzymatic modification of seaweed food hydrocolloids
复制标题
DOI：
10.1016/j.tifs.2021.01.052
复制
发表时间：
2021-03
影响因子：
15.3
通讯作者：
Nanna Rhein-Knudsen;A. Meyer
中科院分区：
文献类型：
--
作者：
Nanna Rhein-Knudsen;A. Meyer
卡拉胶、琼脂和海藻酸盐是从海藻中提取的碳水化合物亲水胶体，由于其独特的凝胶性质，在食品、制药和生物技术应用中被用作增稠剂和胶凝剂。这些水胶体是从一组高产的栽培海藻(海洋大型藻类)中商业提取的。海藻生长过程中的海藻类型和生物环境因素决定了海藻水胶体的化学和流变性。对这些海藻水胶体的生物合成和微生物降解的新见解包括发现独特的酶，这些酶催化碳水化合物聚合物中影响水胶体性质的特定结构变化。范围和方法在本综述中，我们描述了海藻水胶体复杂的化学结构、凝胶机制和生物合成途径。我们概述了催化这些亲水胶体变化的新型酶和酶反应，并讨论了这一新的酶知识如何使海藻水胶体的加工和应用进一步技术进步。主要发现和结论海藻属和真海藻属的红色海藻是卡拉胶的主要商业来源，江豚属和石龙属的物种是琼脂的主要来源，海带属和巨囊藻属的棕色海藻目前是海藻酸盐的主要来源。最近的进展加深了我们对这些亲水胶体生物合成和微生物降解过程中所涉及的酶反应的理解，特别是发现了独特的下同分异构酶、脱脂酶和海藻酸盐裂解酶过程。这一新的认识为重新思考这些亲水胶体的来源和提取方案提供了基础，因为这些酶可以催化不同的分子变化来改善亲水胶体的物理性质。
BackgroundCarrageenan, agar, and alginate are seaweed-derived carbohydrate hydrocolloids which are used as thickening and gelling agents in foods, pharma and biotechnology applications due to their unique gelation properties. These hydrocolloids are extracted commercially from a set of high-yielding, cultivated seaweeds (marine macroalgae). The seaweed type and biological and environmental factors during seaweed growth determine the chemical and rheological hydrocolloid properties. New insight into biosynthesis and microbial degradation of these seaweed-derived hydrocolloids includes discovery of unique enzymes that catalyze specific structural changes in the carbohydrate polymers which affect the hydrocolloid properties.Scope and approachIn this review we describe the intricate chemical structures, gelation mechanisms and biosynthesis routes of seaweed hydrocolloids. We provide an overview of novel enzymes and enzyme reactions that catalyze changes in these hydrocolloids, and discuss how this new enzyme knowledge may enable further technological advancements in processing and applications of seaweed hydrocolloids.Key Findings and ConclusionsThe red seaweeds from the generaKappaphycusandEucheumaare key commercial sources of carrageenan, species from the genera Gracilaria andGelidiumare the main sources of agar, and brown seaweeds from the genera Laminaria and Macrocystis are currently the main sources of alginate. Recent progress has advanced our understanding of enzymatic reactions involved in the biosynthesis and microbial degradation of these hydrocolloids and especially uncovered unique epimerase, desulfatase, and alginate lyase processes. This new knowledge provides a basis for rethinking the sources and extraction protocols of these hydrocolloids because such enzymes can catalyze distinct molecular changes to improve the physical properties of the hydrocolloids.