Bacterial cellulose: 'Super Materials' in nature

What is bacterial cellulose？

Bacterial Cellulose (BC) is a natural polymer substance synthesized by specific bacteria, such as Acetobacter xylinum. Unlike plant cellulose, bacterial cellulose has a finer and more uniform structure, showing unique physical, chemical and biological characteristics, thus showing great application potential in many fields, especially in green and sustainable development. It has important significance.

Technical Parameters of Dibacterial Cellulose

parameter	unit	Technical indicators/typical values	illustrate
Appearance	-	White, slightly transparent film or glue	Bacterial cellulose is white or slightly transparent film/colloidal, with a smooth, soft appearance and high transparency.
Fiber diameter	nanometer	20-100 nm	Bacterial cellulose has fiber diameters usually 20-100 nanometers, and the extremely fine fiber structure provides high strength and stability.
Tensile strength	MPa	250-350 MPa	The tensile strength is much higher than most plant cellulose and is suitable for high-strength applications.
Elastic modulus	GPa	15-25 GPa	The elastic modulus is high and shows strong rigidity, and is suitable for applications with high strength and stability requirements.
Water content	%	60-80%	Bacterial cellulose has a high moisture content and maintains good performance in humid environments.
Moisture retention	%	80-90%	Bacterial cellulose can retain a lot of moisture and is suitable for use in humid environments.
proportion	-	1.5-1.6	The specific gravity of bacterial cellulose is low, making it easy to process and mold.
Crystallization degree	%	60-85%	Bacterial cellulose has a high crystallinity, giving it strong structural stability.
Tensile resistance	N/mm²	55-90 N/mm²	It has excellent tensile resistance and can withstand large external tension forces, and is widely used in various high-durability materials.
Breathability	cm³/m²·d·atm	3000-7000 cm³/m²·d·atm	It has good breathability and is suitable for breathable packaging, dressings and other environmental control applications.
Thermal stability	°C	170-210°C	Bacterial cellulose has high thermal stability and can maintain performance under high temperature environments.
pH stability range	pH	3-9	Chemically stable within the pH range of 3-9, suitable for application in different acid and alkali environments.
Biodegradability	-	Complete biodegradation	Bacterial cellulose can degrade naturally, meets environmental protection requirements, and will not cause pollution to the environment.
Chemical composition	-	Pure cellulose	The main component is glucose units, which are connected through β-1,4 glycosidic bonds, and have a high purity.
Surface area	m²/g	200-300 m²/g	The high surface area makes it widely used in adsorption, composite materials and catalyst support materials.
Solubility	-	Insoluble in water, slightly soluble in acid and alkali solutions	Bacterial cellulose is insoluble in water, but is partially soluble in acidic or alkaline solutions, showing strong chemical stability.
UV resistance	-	excellent	Bacterial cellulose can effectively resist ultraviolet rays and is suitable for use as an anti-ultraviolet material and is used in packaging and other fields.
Biocompatibility	-	High biocompatibility	Suitable for medical field, has good biocompatibility and does not trigger immune rejection reactions.
Antibacterial	-	Can be customized as needed	Antibacterial agents can be added to bacterial cellulose according to different application needs to improve the antibacterial effect.

Preparation method of three bacterial cellulose

The preparation methods of bacterial cellulose usually include liquid culture method, solid culture method and genetic engineering improvement, among which liquid culture method is the most commonly used one.

1 Liquid culture method

Liquid culture method refers to the synthesis of bacterial cellulose by culturing specific bacteria in liquid culture medium (such as Acetobacter xylinum). The process is as follows:

Culture medium preparation:

Main ingredients: glucose, nitrogen sources (such as amino acids or ammonia salts), mineral salts and trace elements.

pH regulation: usually between 4.5-6.0 to promote bacterial growth.

Inoculation and fermentation:

Acetobacter xylinum was inoculated into liquid culture medium and the fermentation process was initiated.

During fermentation, bacteria convert glucose into bacterial cellulose and accumulate in film or gelatinous form.

Fermentation conditions:

Temperature: 28-30°C.

pH: 4.5-6.0.

Incubation time: usually 5-7 days.

Harvest and post-processing:

After fermentation is completed, the bacterial cellulose is removed and washed with water to remove impurities in the culture medium.

The washed bacterial cellulose can be further dried and processed into films or other forms.

2. Solid culture method

Solid culture method uses solid culture medium, and bacteria will synthesize bacterial cellulose on solid surfaces or substrates. This method is relatively water-saving and suitable for large-scale production.

3. Genetic engineering improvement

Genetic engineering technology can be used to optimize the genome of bacteria and improve the production efficiency of bacterial cellulose. For example, by modifying the genes of C. acetate, it can improve its ability to synthesize cellulose, increase yield, and improve quality.

Application fields of four bacterial cellulose

Bacterial cellulose is widely used in the following fields due to its excellent mechanical properties, biocompatibility and environmental protection properties:

1. Medical field

Trauma dressing: Bacterial cellulose is widely used in trauma dressings in the medical field, which can effectively accelerate wound healing, and is especially suitable for burns, trauma and other diseases.

Artificial skin: Bacterial cellulose is used as artificial skin material to help burn patients repair their skin and provide temporary protective barriers.

Drug sustained-release system: Bacterial cellulose has a high nanostructure and can be used as a drug sustained-release carrier to improve the bioavailability of drugs and reduce side effects.

2. Environmental protection field

Water treatment: Bacterial cellulose can adsorb harmful substances in water, such as heavy metals, and is often used in the field of water treatment.

Air purification: In air purification equipment, bacterial cellulose is used as a filtering material to effectively remove pollutants and harmful gases in the air.

3. Food packaging

Bacterial cellulose has become a green and environmentally friendly food packaging material due to its excellent biodegradability. It can not only replace traditional plastic packaging, but also effectively extend the shelf life of food and reduce environmental pollution.

4. Nanotechnology

Due to its high specific surface area and good mechanical properties, bacterial cellulose is widely used in nanotechnology fields, such as as catalyst carriers, sensors and nanocomposite materials.

5. Textiles and composite materials

Bacterial cellulose

Conclusion

As an innovative natural polymer material, Compared with traditional plant cellulose, bacterial cellulose has significant advantages in structure, performance and sustainability, especially in industries such as medical, environmentally friendly and high-performance composites. It not only meets the requirements of green environmental protection and sustainable development, but also has high biodegradability and biocompatibility, which can effectively reduce environmental pollution and promote the recycling of resources.bacterial cellulose has a wide range of application prospects in many fields.

With the continuous advancement of production technology and the application of genetic engineering improvement, the production cost of bacterial cellulose will gradually decrease and industrial application will become more extensive. From trauma dressings to environmentally friendly packaging, from high-performance composite materials to nanotechnology, the diversified application of bacterial cellulose will promote innovative development in multiple industries and become an important part of the field of green materials in the future.

Looking ahead, bacterial cellulose is not only a breakthrough in materials science, but also an important force in promoting sustainable development, environmental protection and biomedical progress. With the increasing emphasis on ecological and environmental protection and green technology, bacterial cellulose will undoubtedly play its unique role in more fields and create a cleaner and healthier future for us.

References

Rinaudo, M. (2008). Biochemistry and applications of bacterial cellulose. Polymer, 49(12), 2727-2735.

This paper details the biochemical properties of bacterial cellulose and its applications in multiple fields, especially in the pharmaceutical and environmental fields.

Yamanaka, S., & Aiba, S. (2004). Bacterial cellulose: A masterpiece of nature's arts. Trends in Biotechnology, 22(5), 145-150.

This paper introduces the production process, structural characteristics and application of bacterial cellulose in industry, and analyzes its advantages as a new material.

Speranza, G., & Bortoluzzi, G. (2016). Bacterial cellulose as a novel green material for biomedical applications. Materials Science and Engineering: C, 60, 221-228.

The application of bacterial cellulose in the field of biomedical science was studied, and its potential as a trauma dressing, artificial skin and drug delivery system was explored.

Singh, AP, & Sharma, RK (2013). Sustainable production of bacterial cellulose: A critical review. Biotechnology Advanceds, 31(3), 442-451.

This review article analyzes the sustainable production methods of bacterial cellulose, especially technological advances in green production and low-cost production.

Nishida, H., & Fujiwara, N. (2010). The potential of bacterial cellulose as a sustainable resource for the textile industry. Journal of Industrial Ecology, 14(6), 991-1002.

This paper explores the application of bacterial cellulose in the textile industry, especially its potential as an alternative material in the context of sustainable development.

Liu, Y., & Chen, Y. (2015). Characterization and applications of bacterial cellulose-based materials. International Journal of Biological Macromolecules, 79, 129-135.

This article describes the properties of bacterial cellulose in detail, including its nanostructure, mechanical properties and its applications in composite materials.

Cheng, K., & Li, C. (2017). Bacterial cellulose in environmental applications: A review. Environmental Science and Pollution Research, 24(17), 15096-15106.

This study reviews the various applications of bacterial cellulose in environmental protection, especially innovative applications in the fields of water treatment and air purification.

Chen, Z., & Zhang, S. (2018). Bacterial cellulose and its applications in biocomposite materials: A review. Composites Part B: Engineering, 144, 186-196.

The application of bacterial cellulose in biological composite materials, especially in environmentally friendly materials, building materials and high-performance composite materials, is reviewed.

Pandey, A., & Sahoo, D. (2014). Applications of bacterial cellulose in the food and pharmaceutical industries. Carbohydrate Polymers, 101, 777-784.

The application of bacterial cellulose in the food and pharmaceutical industries was discussed, with an emphasis on its innovative application as a food packaging material and drug delivery vehicle.

He, J., & Zeng, L. (2020). Fabrication and characterization of bacterial cellulose-based nanocomposites for biomedical applications. Journal of Materials Science, 55(7), 2107-2116.