Thomas Juanit, Roy Payel, Ghosh Arabinda, Mete Megha, Sil Samir Kumar, Das Deeplina
Department of Bioengineering, NIT Agartala, Tripura, 799046, India.
Department of Computational Biology and Biotechnology, Mahapurusha Srimanta Sankaradeva Viswavidyalaya, Assam, 781032, India.
Carbohydr Res. 2024 Apr;538:109075. doi: 10.1016/j.carres.2024.109075. Epub 2024 Mar 23.
The global demand for therapeutic prebiotics persuades the quest for novel exopolysaccharides that can retard the growth of pathobionts and healthcare-associated pathogens. In this regard, an exopolysaccharide (3.69 mg/mL) producing strain showing prebiotic and antibiofilm activity was isolated from indigenous pineapple pomace of Tripura and identified as Bacillus subtilis PR-C18. Zymogram analysis revealed EPS PR-C18 was synthesized by levansucrase (∼57 kDa) with a maximal activity of 4.62 U/mg. Chromatography techniques, FTIR, and NMR spectral data revealed the homopolymeric nature of purified EPS with a molecular weight of 3.40 × 10 Da. SEM and rheological study unveiled its microporous structure and shear-thinning effect. Furthermore, EPS PR-C18 showed remarkable emulsification, flocculation, water retention, water solubilization, and antioxidant activity. DSC-TGA data demonstrated its high thermostability and cytotoxicity analysis verified its nontoxic biocompatible nature. In addition, the antibiofilm activity of EPS PR-C18 was validated using molecular docking, molecular simulation, MM-GBSA and PCA studies, which exhibited its strong binding affinity (-20.79 kcal/moL) with PelD, a virulence factor from Pseudomonas aeruginosa. Together, these findings support the future exploitation of EPS PR-C18 as an additive or adjuvant in food and pharmaceutical sectors.
全球对治疗性益生元的需求促使人们寻求能够抑制病原菌和医疗保健相关病原体生长的新型胞外多糖。在这方面，从特里普拉当地菠萝果渣中分离出一株具有益生元和抗生物膜活性的胞外多糖产生菌株（3.69毫克/毫升），并鉴定为枯草芽孢杆菌PR-C18。酶谱分析表明，EPS PR-C18是由果聚糖蔗糖酶（约57 kDa）合成的，最大活性为4.62 U/mg。色谱技术、傅里叶变换红外光谱（FTIR）和核磁共振（NMR）光谱数据显示，纯化后的EPS为均聚物，分子量为3.40×10 Da。扫描电子显微镜（SEM）和流变学研究揭示了其微孔结构和剪切变稀效应。此外，EPS PR-C18表现出显著的乳化、絮凝、保水、增溶和抗氧化活性。差示扫描量热法（DSC）-热重分析法（TGA）数据表明其具有高耐热性，细胞毒性分析证实了其无毒的生物相容性。此外，通过分子对接、分子模拟、MM-GBSA和主成分分析（PCA）研究验证了EPS PR-C18的抗生物膜活性，其与铜绿假单胞菌的毒力因子PelD具有很强的结合亲和力（-20.79千卡/摩尔）。总之，这些发现支持了未来将EPS PR-C18用作食品和制药行业的添加剂或佐剂。
