International Center of Excellence in Seafood Science and Innovation, Faculty of Agro-Industry, Prince of Songkla University, Hat Yai, Thailand.
Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.
J Food Biochem. 2021 Jan;45(1):e13569. doi: 10.1111/jfbc.13569. Epub 2020 Nov 29.
Chitin was isolated from Pacific white shrimp (Litopenaeus vannamei) shell by demineralization and deproteinization using 1 M HCl (1:20, w/v) for 2 hr and 1 M NaOH (1:30 w/v) for 80 min at 70ºC, respectively, with 29.96% optimum yield. Thereafter, the chitin was deacetylated at various temperatures for different times, in which the chitosan prepared at 130ºC for 4 hr (CS-130-4) showed higher yield (73.11%), crystallinity index (19.75%), and 85.28% degree of deacetylation (DDA) as measured by H-NMR. CS-130-4 was then conjugated to epigallocatechin gallate (EGCG) at various concentrations (2-8%, w/w of chitosan). CS-130-4 was grafted with 8% EGCG (CE-8) had the higher conjugation efficiency (92.63%) and antimicrobial/antioxidant activities as compared to other conjugates (p < .05). H-NMR analysis also confirmed the successful conjugation of CE-8. All the conjugates were completely water soluble. Therefore, CE-8 may be used as the natural antimicrobial and antioxidant agents in various food products. PRACTICAL APPLICATIONS: Shrimp shells are generally considered as processing by-products of the shellfish industries and can cause environmental pollution when improperly disposed. Chitosan from shrimp shells has been widely produced but it is soluble mainly in acidic solutions, which limits its applications. However, grafting of epigallocatechin gallate (EGCG) onto chitosan yielded water-soluble conjugates with enhanced antioxidant and antimicrobial properties. Although several preservatives have been applied in foods, their health hazards have been a major concern. To mitigate this limitation, chitosan-EGCG conjugates could be employed as alternative natural preservatives or additives for shelf-life extension of various foods.
从太平洋白虾（凡纳滨对虾）壳中通过使用 1 M HCl（1:20，w/v）在 70°C 下脱矿质和用 1 M NaOH（1:30 w/v）脱蛋白 2 小时和 80 分钟分别分离甲壳素，产率为 29.96%。此后，在不同温度下将甲壳素脱乙酰化不同时间，其中在 130°C 下 4 小时制备的壳聚糖（CS-130-4）显示出更高的产率（73.11%）、结晶度指数（19.75%）和 85.28%脱乙酰度（DDA），通过 H-NMR 测量。然后将 CS-130-4 与不同浓度（壳聚糖的 2-8%，w/w）的表没食子儿茶素没食子酸酯（EGCG）缀合。CS-130-4 与 8% EGCG（CE-8）接枝具有更高的缀合效率（92.63%）和抗菌/抗氧化活性，与其他缀合物相比（p<.05）。H-NMR 分析也证实了 CE-8 的成功缀合。所有缀合物均完全溶于水。因此，CE-8 可作为各种食品中的天然抗菌和抗氧化剂。实际应用：虾壳通常被认为是贝类工业的加工副产品，如果处理不当，会造成环境污染。虾壳中的壳聚糖已经得到广泛生产，但主要溶解在酸性溶液中，这限制了它的应用。然而，将表没食子儿茶素没食子酸酯（EGCG）接枝到壳聚糖上可得到具有增强的抗氧化和抗菌性能的水溶性缀合物。尽管已经在食品中应用了几种防腐剂，但它们的健康危害一直是一个主要问题。为了减轻这一限制，可以将壳聚糖-EGCG 缀合物用作各种食品的替代天然防腐剂或添加剂，以延长保质期。
