Department of Chemistry, Federal Technological University of Paraná, Via do Conhecimento, km 01, Bairro Fraron, CEP: 85503-390 Pato Branco, PR, Brazil.
Department of Chemistry, Federal Technological University of Paraná, Via do Conhecimento, km 01, Bairro Fraron, CEP: 85503-390 Pato Branco, PR, Brazil.
Carbohydr Polym. 2015;127:390-9. doi: 10.1016/j.carbpol.2015.03.045. Epub 2015 Mar 28.
D-Glucans possess immunomodulatory activities and potential for the development of new therapeutic agents. Biological activities can be enhanced in these biopolymers through chemical derivatization, e.g., carboxymethylation. This work presents the carboxymethylation, characterization and the evaluation of antioxidant activities of the exocellular (1 → 6)-β-D-glucan produced by Lasiodiplodia theobromae MMPI. Thermal analysis indicated that the native and carboxymethylated polysaccharides presented four stages of mass-loss. The first stage occurred at 125°C (loss of water) with two consecutive events of mass loss (200-400°C) attributed to polymer degradation and the fourth stage between 425 and 620°C (final decomposition). Scanning electron microscopy analysis indicated that the gross morphological features of lasiodiplodan were ruptured following carboxymethylation. X-ray diffractometry analysis demonstrated that the native and carboxymethylated polysaccharides presented a non-crystalline structure. Carboxymethylation contributed to improving the polysaccharide's water solubility and antioxidant capacity.
D-葡聚糖具有免疫调节活性和开发新治疗药物的潜力。通过化学衍生化，例如羧甲基化，可以增强这些生物聚合物的生物活性。本工作对热带假丝酵母 MMPI 产生的胞外（1→6）-β-D-葡聚糖进行了羧甲基化、表征和抗氧化活性评价。热分析表明，天然和羧甲基化多糖在质量损失过程中表现出四个阶段。第一阶段发生在 125°C（失水），与聚合物降解相关的两个连续质量损失事件（200-400°C），第四阶段在 425 和 620°C 之间（最终分解）。扫描电子显微镜分析表明，拉氏多孢菌的宏观形态特征在羧甲基化后破裂。X 射线衍射分析表明，天然和羧甲基化多糖具有非晶结构。羧甲基化有助于提高多糖的水溶性和抗氧化能力。
