Knowledge atlas Nature

Bacterial nanocellulose (BNC)

Bacterial nanocellulose is nanoscale cellulose produced through fermentative processes of certain microorganisms. It holds enhanced and improved properties over the plant-based cellulose. It does not demand pre-treatment and is synthesized as pure cellulose with ultrafine network architecture. It has a significant level of application in biotechnological, pharmaceutical, medical, and food industries.

Name of Material in the local and Latin language: Bakterijska nanoceluloza
Type of Material: Organic
Commonly Found Locations: Laboratory environment
Major Industrial Producers or Suppliers: Axcelon Biopolymers Corporation (Canada)

Colour: Semi-transparent. Can reach the gradient of yellow and white, possibly violet and indigo (based on applied culture, feedstock, enzymes)
Density: Low
Hardness: BNC is characterized by high elasticity making it modular and adaptable in producing shapes, but mechanically it is a very resistant material.
Melting/Boiling Point: Depending on the bacteria used for production
Solubility: Water insoluble
Structure: BNC is assembled into a nanostructured network of glucan polymers.
Chemical Composition: Linear polysaccharide composed of β-D-glucopyranose monomers linked by β-1,4-glycosidic linkages.

Industrial and Crafts Applications: BNC finds its application in biotechnological, pharmaceutical, medical, and food industry. Its elasticity allows for it to be used for production of prosthetic blood vessels; due to its porosity it allows the passing of a medicament and keeps the pathogen outside.
Environmental Impact: Production of BNC is fully environment-friendly and produces non-remarkable carbon footprint. Its production is often based on degrading the already existing waste and pollutants, such as PET (polyethylene terephthalate) bottles.

Extraction Methods: BNC is produced in the fermentative process of Gluconacetobacter, Komagataeibacter, Enterobacter, Rhodococcus, and Sarcina bacterial genera. In the process, pure BNC with ultrafine network architecture is synthesised into characteristic ribbon-like microfibrils. Under static cultivation conditions, BNC is obtained as thick gel sheets, and under the dynamic ones BNC pellets are formed.
Processing Techniques: BNC is pure cellulose shaped according to the surroundings during the fermentative process. In simple words, BNC is shaped based on the dishes and elements placed in the surroundings in which bacterial culture is being cultivated. BNC gel is washed in KOH solution until it becomes white. By means of drying (air or at 50° C) BNC is obtained in film form, and by lyophilisation it appears as foam. BNC of certain properties can be activated by using different enzymes, depending on the final purpose of the object to be made.
Sustainability and Environmental Considerations: As all other biopolymers, BNC is fully biodegradable. However, due to its still developing mass production and applications, it is not entirely determined what the full extent of its impact on the environment is.
Recycling and Waste Management: Recycling BNC, as well as other bioplastics, results in the production of materials that are of wide use and high economic value. These materials can be used for creating the same object in the same material with the same or higher value. BNC waste can be reused as feedstock for the new fermentative process over and over again.

Current Research and Developments: Projects such as EcoPlastiC, conducted by a five-partner consortium, or BioICEP, as a pan European-Chinese collaboration, formed to reduce the burden of plastic waste, are resulting in new techniques and technologies for increased mass application of biomaterials. These projects are based on maintaining a sustainable cycle of waste degradation and the production of new materials. Links: BioICEP: https://www.bioicep.eu/project.php; EcoPlastiC: https://ecoplasticproject.eu/partners
Regulations or Restrictions: EU Bioeconomy Strategy (2018), EU Plastics Strategy (2018), EU Green Deal (2019), Single-Use Plastics Directive (2019) incl. restrictions on oxo-degradable plastics, New EU Circular Economy Action Plan (2020), EU Climate Law (2021) & EU Taxonomy (2020), Sustainable Carbon Cycles (2021), Packaging & Packaging Waste Directive (revision 2022), EU Regulation on recycled plastic materials and articles intended to come into contact with foods (2022), Substantiating Claims on environmental performance (2022), Sustainable Products Initiative (2022) / Proposal for a new Ecodesign for Sustainable Products Regulation, Policy Framework for biobased, biodegradable and compostable plastics (2022), Waste Framework Directive (revision 2023).
Relevant Organizations, Associations, Producers: Bioplastech, PerPETual, Axcelon Bioploymers Corporation