What are the raw materials for producing bacterial cellulose films?

The raw materials for the production of bacterial cellulose films are mainly synthesized by glucose or other fermentable carbon sources through bacteria (such as Gluconacetobacter xylinus in the genus Acetic acid bacteria ) under suitable culture conditions. The following are the raw materials and culture medium ingredients commonly used in the production process of bacterial cellulose films:

1. Carbon source

• Glucose : The most commonly used carbon source, providing the main energy source for bacteria to synthesize cellulose.

• Sucrose : It can replace glucose as a carbon source.

• Fructose, glycerin, lactose, etc .: Other fermentable carbon sources can also be used for the synthesis of cellulose, but the efficiency may be different.

2. Nitrogen source

• Yeast extract : Provides nitrogen and other nutrients needed for bacterial growth.

• Peptone : Another commonly used nitrogen source, which can promote bacterial growth and cellulose synthesis.

• Ammonium nitrate, ammonium chloride : It can provide an inorganic nitrogen source.

3. Inorganic salt

• Potassium dihydrogen phosphate (K ₂ HPO ₄ ) : Provides phosphorus elements to bacteria and supports cell metabolic activities.

• Magnesium sulfate ( MgSO ₄ ) : Provides magnesium ions to bacteria and promotes the activity of enzymes.

• Calcium chloride ( CaCl ₂ ) : Sometimes added to improve cellulose yield and quality.

4. Other additives

• Acetic acid : As an acidic regulator, maintain the pH value of the culture medium within an appropriate range (usually 4.5-6.0) to facilitate the optimal growth of bacteria.

• Ethanol : Sometimes adding a small amount of ethanol can increase the yield of bacterial cellulose .

• Other vitamins and trace elements : Depending on the specific needs, some vitamins (such as vitamin B1) or trace elements may be added to promote bacterial growth.

5. Water

• Used to prepare culture medium to ensure that the raw materials can be fully dissolved and provide a suitable growth environment for bacteria.

During the production process, these feedstocks are usually mixed and prepared into liquid culture medium, followed by inoculation of appropriate bacteria. During fermentation, bacteria convert the carbon source into cellulose and form a thin film on the liquid surface. After this film is collected, cleaned and dried, it is a bacterial cellulose film。

This film has a wide range of applications in biomedical, food packaging, cosmetics and other fields, and has attracted much attention for its high purity, high strength and biocompatibility.