Vieira Cláudia Brandão, Sousa Juliana Rabelo, Do Vale Diego Alves, Guimarães Cybele Pinheiro, de Sousa Karolina Costa, Mattos Adriano Lincoln Albuquerque, Silva André Luís Coelho, de Sá Moreira Souza Filho Men, Souza Bartolomeu Warlene Silva
Department of Fishing Engineering, Federal University of Ceara, Campus do Pici, 825, 60356-000, Fortaleza, CE, Brazil.
Tropical Agroindustry / Embrapa, Rua Dr. Sara Mesquita, 2270, Planalto Pici, Fortaleza, CE, CEP: 60511-110, Brazil.
Carbohydr Res. 2025 Jun;552:109473. doi: 10.1016/j.carres.2025.109473. Epub 2025 Mar 28.
Sulfated polysaccharide (SP) was successfully extracted from rhodophyta Gracilaria birdiae cultivated in northeast Brazil. For the first time, edible SP films from G. birdiae were formulated by the casting method using an experimental design 3, in which the variables were SP concentration and glycerol concentration. A polysaccharide extraction yield of 26.4 % was obtained through hot aqueous extraction and purification by dialysis. The chemical composition indicated the quality of the SP due to the high total carbohydrate (85.1 %) and sulfate (8.1 %) contents and the absence of proteins. Structural characterization showed the presence, besides the sulfate group, of the methylated monosaccharide residues, namely 3,6-α-l-anhydrogalactose-2-O-methyl and β-d-galactose-6-O-methyl with methylation degree of 0.257. In addition, the polysaccharide chain was mainly composed of 3,6-α-l-anhydrogalactose → β-d-galactose, α-l-galactose-6-sulfate → β-d-galactose, β-d-galactose → 3,6-α-l-anhydrogalactose, and β-d-galactose → α-l-galactose-6-sulfato. SP was also considered thermostable, showing a thermal degradation pattern similar to that of galactans. Through experimental design, it was observed that the film formulation with 2 % SP and 0.2 % glycerol presented the best mechanical, physico-chemical and optical properties for application in food packaging.
硫酸化多糖（SP）成功地从巴西东北部养殖的红藻 Gracilaria birdiae 中提取出来。首次采用实验设计3通过流延法制备了来自 Gracilaria birdiae 的可食用SP薄膜，其中变量为SP浓度和甘油浓度。通过热水提取和透析纯化获得了26.4%的多糖提取率。化学组成表明该SP质量良好，因其总碳水化合物含量高（85.1%）、硫酸盐含量高（8.1%）且不含蛋白质。结构表征显示除硫酸基团外，还存在甲基化单糖残基，即3,6-α-L-脱水半乳糖-2-O-甲基和β-D-半乳糖-6-O-甲基，甲基化程度为0.257。此外，多糖链主要由3,6-α-L-脱水半乳糖→β-D-半乳糖、α-L-半乳糖-6-硫酸盐→β-D-半乳糖、β-D-半乳糖→3,6-α-L-脱水半乳糖和β-D-半乳糖→α-L-半乳糖-6-硫酸酯组成。SP也被认为具有热稳定性，其热降解模式与半乳聚糖相似。通过实验设计观察到，含有2%SP和0.2%甘油的薄膜配方在食品包装应用中表现出最佳的机械、物理化学和光学性能。
