Preparation method of bacterial cellulose

Bacterial Cellulose (BC) is a polysaccharide material synthesized by fermentation by certain bacteria, such as glucosaccharides of the genus Acetococcus. Due to its excellent mechanical properties, biocompatibility and high purity, bacterial cellulose has a wide range of applications in medicine, food, cosmetics and other fields. Here are the general methods for preparing bacterial cellulose:

1. Selection and culture of strains:

Select the appropriate bacterial strain (such as glucosaccharides and soreness) for culture.

The strains were pre-cultured in liquid culture medium to obtain sufficient active bacteria.

2. Preparation of culture medium:

The commonly used medium is HS medium ( Hestrin-Schramm medium), which includes glucose, yeast extract, peptone, sodium citrate and potassium dihydrogen phosphate.

The composition of the culture medium can be adjusted as needed to optimize the yield and quality of bacterial cellulose.

3. Fermentation culture:

The pre-cultured bacteria are inoculated into the prepared medium.

Fermentation is carried out at an appropriate temperature (usually 25~30°C ) and at standstill conditions. Standal culture can promote the formation of thin films of bacterial cellulose on the liquid surface.

The fermentation time is usually 7-14 days, depending on the required cellulose thickness and quality.

4. Collection and purification of cellulose:

After fermentation is completed, the bacterial cellulose film is removed from the surface of the culture medium.

Wash the cellulose film multiple times with distilled water to remove media residues and bacteria.

The washed cellulose film is treated with a base (such as NaOH ) to completely remove bacterial cells and other impurities.

Finally, neutralize the lye with a lot of distilled water until the pH is close to neutral.

5.Dry and preserve:

The purified bacterial cellulose can be dried as needed (such as air drying, freeze-drying, etc.), or stored in a wet state.

These steps can be adjusted and optimized according to the specific application requirements to improve the yield and quality of bacterial cellulose.