Rodrigues Liliana A, Radojčić Redovniković Ivana, Duarte Ana Rita C, Matias Ana A, Paiva Alexandre
Food and Health Division, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal.
Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal.
ACS Omega. 2021 Oct 20;6(43):28729-28741. doi: 10.1021/acsomega.1c03402. eCollection 2021 Nov 2.
The versatility of chitin and its derivatives has allowed their utilization in a wide range of applications, from wastewater treatment to pharmaceutical or biomedical industries. However, even though the extraction method used industrially is extremely efficient, it involves the use of strong acids and bases and results in the disposal of large quantities of toxic effluents. Deep eutectic systems (DESs) have emerged as a promising new class of alternative solvents, including for chitin recovery. Yet, the assessment of their toxicity has often been neglected. Therefore, in this work, the phytotoxicity of choline chloride (ChCl)/organic acid-based DESs toward wheat seeds was evaluated by measuring different growth parameters and stress biomarkers. DESs were then explored for the efficient recovery of chitin contained in brown crab shell residues at varying conditions of temperature and processing time as well as with and without water addition. The obtained chitin was then characterized through different analytical techniques and compared to a standard as well as to chitin obtained by a conventional acid/alkaline hydrolysis. Results have shown that by applying a ChCl/lactic acid-based DES (which was the system that showed the least phytotoxic effects on wheat; EC50 ≥ 1.6 mg/mL) at 130 °C, it was possible to obtain pure chitin (up to 98%) with characteristics similar to those presented by commercial chitin or chitin recovered by conventional hydrolysis in a shorter time (more than 8-fold faster), thus suggesting that ChCl/organic acid-based DESs can truly represent a low-phytotoxic alternative extraction media for the recovery of chitin from the crab shell biomass.
几丁质及其衍生物的多功能性使其可用于广泛的应用领域，从废水处理到制药或生物医学行业。然而，尽管工业上使用的提取方法效率极高，但它涉及使用强酸和强碱，并导致大量有毒废水的排放。深层共晶体系（DESs）已成为一类有前景的新型替代溶剂，包括用于几丁质的回收。然而，它们的毒性评估常常被忽视。因此，在这项工作中，通过测量不同的生长参数和应激生物标志物，评估了氯化胆碱（ChCl）/有机酸基DESs对小麦种子的植物毒性。然后探索了DESs在不同温度和处理时间条件下以及添加和不添加水的情况下，从棕色蟹壳残渣中高效回收几丁质的方法。然后通过不同的分析技术对获得的几丁质进行表征，并与标准品以及通过传统酸/碱水解获得的几丁质进行比较。结果表明，通过在130℃下应用基于ChCl/乳酸的DES（该体系对小麦显示出最小的植物毒性作用；EC50≥1.6mg/mL），可以在更短的时间内（快8倍以上）获得特性与商业几丁质或通过传统水解回收的几丁质相似的纯几丁质（高达98%），因此表明基于ChCl/有机酸的DESs确实可以代表一种低植物毒性的替代提取介质，用于从蟹壳生物质中回收几丁质。
