Sabroso Esteban, Martínez José M, Sánchez-León Enrique, Rodríguez Nuria, Amils Ricardo, Abrusci Concepción
Department of Molecular Biology, Faculty of Sciences, Autonomous University of Madrid (UAM), Cantoblanco, 28049 Madrid, Spain.
Molecular Ecology of Extreme Environments, Scientific Program Interactions with the Environment, Centro de Biología Molecular Severo Ochoa (UAM-CSIC), 28049 Madrid, Spain.
Polymers (Basel). 2025 Aug 30;17(17):2362. doi: 10.3390/polym17172362.
The extremophilic strain Zn11_249 was isolated from Salar de Uyuni, an environment with high salinity, among other extreme factors. This study researched the optimised production, characterisation, antioxidant activity, and cytotoxicity of exopolysaccharides (EPS) produced by this strain under different ionic stresses. Zn11_249 was cultured in a minimal medium with glucose as the sole carbon source as a control, and under kosmotropic (NaCl, 1 M) and chaotropic (LiCl, 0.3 M) conditions, yielding EPS, EPS, and EPS, respectively. Maximum EPS production (336 mg/L) occurred under chaotropic conditions after 96 h. EPSs were characterised using the following techniques: Gas chromatography (GC-MS); Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR); Thermogravimetric Analysis (TGA); and Differential Scanning Calorimetry, (DSC). The results showed differences between the molecular weights for EPS (3.9 × 10 Da), EPS (3.9 × 10 Da), and EPS (5.85 × 10 Da). Their monosaccharide molar ratios (%) were 40/25/25/10 in EPS, 10/30/30/30 in EPS, and 25/25/25/25 in EPS, composed of mannose, galactose, rhamnose, and glucose, respectively. Functional group analysis confirmed their heteropolysaccharide nature. Thermal profiles suggest the potential of these exopolysaccharides as biomaterials. Antioxidant tests demonstrated significant activity against DPPH, OH, and O radicals, while cytotoxicity assays showed no toxicity. These results highlight the biotechnological potential of EPSs from Zn11_249 for biomedical and cosmetic uses.
嗜极菌株Zn11_249是从乌尤尼盐沼分离得到的，该环境除了其他极端因素外，还具有高盐度。本研究探讨了该菌株在不同离子胁迫下产生的胞外多糖（EPS）的优化生产、表征、抗氧化活性和细胞毒性。Zn11_249在以葡萄糖作为唯一碳源的基本培养基中培养作为对照，并在促溶剂（1 M NaCl）和离液剂（0.3 M LiCl）条件下培养，分别产生EPS、EPS和EPS。在离液剂条件下培养96小时后，EPS产量最高（336 mg/L）。使用以下技术对EPS进行表征：气相色谱（GC-MS）；衰减全反射傅里叶变换红外光谱（ATR-FTIR）；热重分析（TGA）；以及差示扫描量热法（DSC）。结果显示，EPS（3.9×10 Da）、EPS（3.9×10 Da）和EPS（5.85×10 Da）的分子量存在差异。它们的单糖摩尔比（%）在EPS中为40/25/25/10，在EPS中为10/30/30/30，在EPS中为25/25/25/25，分别由甘露糖、半乳糖、鼠李糖和葡萄糖组成。官能团分析证实了它们的杂多糖性质。热分析表明这些胞外多糖具有作为生物材料的潜力。抗氧化测试表明对DPPH、OH和O自由基具有显著活性，而细胞毒性试验表明无毒性。这些结果突出了Zn11_249产生的EPS在生物医学和化妆品用途方面的生物技术潜力。
