Rühs Patrick A, Storz Flavian, López Gómez Yuly A, Haug Matthias, Fischer Peter
1Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.
2Department of Bioengineering, UC Berkeley, Berkeley, CA 94702 USA.
NPJ Biofilms Microbiomes. 2018 Sep 5;4:21. doi: 10.1038/s41522-018-0064-3. eCollection 2018.
Bacterial cellulose is a remarkable fibrous structural component of biofilms, as it forms a mechanically strong hydrogel with high water adsorption capabilities. Additionally, bacterial cellulose is biocompatible and therefore of potential interest for skin regeneration and wound healing applications. However, bacterial cellulose produced through conventional production processes at water-air interfaces lack macroporosity control, which is crucial for regenerative tissue applications. Here we demonstrate a straightforward and efficient approach to form a macroporous bacterial cellulose foam by foaming a mannitol-based media with a bacterial suspension of . The bacterial suspension foam is stabilized with Cremodan as a surfactant and viscosified with Xanthan preventing water drainage. Further foam stabilization occurs through cellulose formation across the foam network. As bacterial cellulose formation is influenced by the viscosity of the growth media, we fine-tuned the concentration of Xanthan to allow for bacterial cellulose formation while avoiding water drainage caused by gravity. With this simple approach, we were able to design 3D bacterial cellulose foams without any additional processing steps. We argue that this templating approach can further be used to design foamy biofilms for biotechnological approaches, increasing the surface area and therefore the yield by improving the exchange of nutrients and metabolic products.
细菌纤维素是生物膜中一种引人注目的纤维结构成分，因为它能形成具有高吸水性的机械强度高的水凝胶。此外，细菌纤维素具有生物相容性，因此在皮肤再生和伤口愈合应用方面具有潜在的应用价值。然而，通过传统生产工艺在水 - 空气界面产生的细菌纤维素缺乏大孔控制，而这对于再生组织应用至关重要。在此，我们展示了一种直接且高效的方法，即通过将基于甘露醇的培养基与一种细菌悬浮液发泡来形成大孔细菌纤维素泡沫。细菌悬浮液泡沫用Cremodan作为表面活性剂进行稳定，并使用黄原胶增稠以防止排水。通过在泡沫网络中形成纤维素进一步实现泡沫稳定。由于细菌纤维素的形成受生长培养基粘度的影响，我们微调了黄原胶的浓度，以允许细菌纤维素形成，同时避免重力导致的排水。通过这种简单的方法，我们能够设计出无需任何额外加工步骤的三维细菌纤维素泡沫。我们认为这种模板方法可进一步用于为生物技术方法设计泡沫生物膜，通过增加表面积从而通过改善营养物质和代谢产物的交换来提高产量。
