LWT - Food Science and Technology ( IF 6 ) Pub Date : 2020-07-20 , DOI: 10.1016/j.lwt.2020.109863 Xing Fu , Yunxue Guo , Yongguo Jin , Meihu Ma
Chitin waste, a highly insoluble biopolymer from sea food industry, can be converted into value-added products with chitinase (EC 3.2.1.14). Here, we purified a cold-adapted chitinase (EaChi39) from the marine bacterium Exiguobacterium antarcticum DW2. The enzyme was mostly activated at 30 °C and remained 35% of the maximal activity at 0 °C. It also showed a broad range of pH stability, high thermostability but low Km values, indicating the strong ability for chitin degradation. As an endo-type chitinase, EaChi39 completely converted colloidal chitin into N-acetylglucosamine (GlcNAc) and oligosaccharides with high yields, which was determined by HPLC (GlcNAc 9.9 mg mL−1, GlcNAc2 14.8 mg mL−1 and GlcNAc3 5.0 mg mL−1). As a novel chitinase from Exiguobacterium genus, EaChi39 displayed advantageous cold-adaptation and thermostability. It may be a superior candidate for bioconversion of seafood by-products in producing bioactive oligosaccharides.
中文翻译:
使用冷适应的几丁质酶对几丁质废物进行生物转化以产生几丁质寡糖
几丁质废物是一种来自海洋食品行业的高度不溶性生物聚合物,可通过几丁质酶转化为增值产品(EC 3.2.1.14)。在这里,我们从海洋细菌南极Exiguobacterium DW2中纯化了一种冷适应的几丁质酶(EaChi39)。该酶主要在30°C下激活,在0°C下仍保持最大活性的35%。它也显示出宽范围的pH稳定性,热稳定性高,但低的ķ米值,指示用于几丁质降解的能力强。作为内切型几丁质酶,EaChi39以高产率将胶体几丁质完全转化为N-乙酰氨基葡糖(GlcNAc)和寡糖,通过HPLC(GlcNAc 9.9 mg mL -1,GlcNAc 2 14.8 mg mL -1和GlcNAc 3 5.0 mg mL -1)。如从一个新颖几丁质酶微小杆菌属,EaChi39显示有利的冷适应和热稳定性。在生产生物活性寡糖中,它可能是海产品副产品生物转化的优良候选者。