CINBIO, Universidade de Vigo, Departament of Chemical Engineering, Faculty of Sciences, Campus Ourense, Edificio Politécnico, As Lagoas 32004 Ourense, Spain.
CINBIO, Universidade de Vigo, Departament of Chemical Engineering, Faculty of Sciences, Campus Ourense, Edificio Politécnico, As Lagoas 32004 Ourense, Spain.
Ultrason Sonochem. 2024 Dec;111:107072. doi: 10.1016/j.ultsonch.2024.107072. Epub 2024 Oct 1.
Sea lettuce, or Ulva spp., dominates global algal biomass and significantly contributes to "green tides.", representing a sustainable source for biomaterials. This study explores an innovative ultrasound-enzyme assisted extraction method with the novel Cellic® CTEC3 enzyme cocktail, applied for the first time in Ulva spp. succesfully enhancing ulvan release and extraction efficiency. Various processing methods, including ultrafiltration and dialysis, were employed to achieve higher ulvan purity. Dialyzation of ulvan resulted in a more purified product with a carbohydrate content up to 55.34 %, a sulfate content up to 21 %, and no glucose contamination. Liquid extracts were fractionated through ultrafiltration, with a 3 kDa MWCO yielding 93.51 % ulvan precipitate, representing 50.28 % of the total extractable ulvan. Sequential ultrafiltration concentrated ulvans but only partially modified their molecular weight distribution. Depolymerization using microwave and HO shifted ulvans towards lower molecular weights, reducing high molecular weight residue. HPSEC confirmed pH-dependent aggregation behavior, with all isolated ulvans having molecular weights above 786 kDa. Hydrolysis methods were compared, with 2-hour 1 M TFA hydrolysis at 121 °C providing the best monosaccharide profile of ulvan. FTIR and NMR analyses showed preservation of sulfation. Rheology indicated biopolymeric behavior and stable gel formation. Ulvans demonstrated nutraceutical potential, being suitable for a low Na and high K diet, with a Na:K ratio as low as 0.14, and were rich in Mg.
海白菜，或 Ulva 属，主导着全球藻类生物量，并对“绿潮”做出了重大贡献，是生物材料的可持续来源。本研究探索了一种创新的超声-酶辅助提取方法，使用新型 Cellic® CTEC3 酶混合物，首次应用于 Ulva spp.，成功提高了岩藻聚糖的释放和提取效率。采用超滤和透析等各种处理方法，以获得更高的岩藻聚糖纯度。岩藻聚糖的透析得到了更纯化的产物，其碳水化合物含量高达 55.34%，硫酸根含量高达 21%，且无葡萄糖污染。通过超滤对液体提取物进行分级，MWCO 为 3 kDa 时可得到 93.51%的岩藻聚糖沉淀，占总可提取岩藻聚糖的 50.28%。顺序超滤浓缩了岩藻聚糖，但仅部分改变了其分子量分布。微波和 HO 的解聚使岩藻聚糖向低分子量移动，减少了高分子量残留。HPSEC 证实了 pH 依赖性聚集行为，所有分离出的岩藻聚糖的分子量均高于 786 kDa。比较了水解方法，121°C 下 1M TFA 水解 2 小时提供了岩藻聚糖的最佳单糖谱。FTIR 和 NMR 分析表明硫酸酯化得到了保留。流变学表明其具有生物聚合物行为和稳定的凝胶形成。岩藻聚糖具有营养保健品的潜力，适合低钠高钾饮食，其钠钾比低至 0.14，并且富含镁。
