1. What is a Biofilm?
A biofilm is a biological layer formed by bacteria and other microorganisms on solid surfaces or in liquid environments. It is primarily composed of polysaccharides and proteins. Bacteria within a biofilm typically exhibit greater resistance to harsh environmental conditions and are more difficult to eliminate using antibiotics and conventional disinfection methods.
In the case of Vibrio species (such as Vibrio parahaemolyticus and Vibrio vulnificus), these are common pathogens in aquatic animals like shrimp and fish. When these bacteria form biofilms, they can adhere to the surfaces of aquatic animals, aquaculture equipment, or structures in the water, leading to diseases such as gastrointestinal disorders, septicemia, and wound infections.
Biofilm Formation (After clustering together, bacteria in a biofilm lose their ability to move as they did when they were in a free-floating (planktonic) state. The “tail” (flagellum) shown is only an illustration of the bacteria’s mobility in their free state) – Source: Institute of Plasma Technology Research
2. How to Disrupt Biofilms in Aquaculture
Disrupting bacterial biofilms—especially those formed by Vibrio species—is crucial for controlling and preventing infections. There are several methods to break down these bacterial biofilms:
2.1. Using Enzymes
Protease enzymes can be an effective solution because they are capable of breaking down the protein components of the biofilm structure. This reduces the biofilm’s adhesion and makes the bacteria more susceptible to elimination.
Additionally, combining protease with enzymes like amylase or cellulase can help degrade the polysaccharide layer of
the biofilm.
Some Protease Enzyme Products
2.2. Using Probiotics
Bacillus spp. and Lactobacillus are capable of secreting enzymes such as polysaccharidase and protease. These enzymes help break down the polysaccharide matrix of the biofilm, making the bacteria within it more vulnerable to elimination.
These microbial strains can also produce quorum sensing inhibitors (QSI), which interfere with the cell-to-cell communication among bacteria in the biofilm. This disruption prevents the development and formation of biofilms.
Using Lactobacillus combined with high-density probiotic like TPD CONTROL to break down bacterial biofilms
2.3. Organic Acids and Other Organic Compounds
Organic acids are effective in breaking down biofilms by lowering the environmental pH, which disrupts the biofilm structure and makes bacteria more vulnerable.
Examples include lactic acid, butyric acid, propionic acid, and especially formic acid. In aquaculture, formic acid can be used to clean systems, prevent biofilm formation, and reduce Vibrio growth.
| Farming Stage | Implementation |
| Before stocking | – Disinfect water using WIIKONC or SDIC. – Clean pond bottom, filtration system, and pipes with enzymes + organic acids (citric, formic, lactic). |
| First week after stocking | – Add probiotics + organic acids to stabilize microflora. – Maintain slightly acidic pH to limit pathogen adhesion. |
| Mid-cycle | – Apply biofilm-degrading enzymes weekly (or after rain/cloudy water). – Combine with water-soluble organic acids to reduce biofilm buildup. – Add Bacillus spp. to compete for surface attachment. |
| When fish/shrimp show weakness | – Use organic acids with enzymes to break bacterial biofilms. – Increase oxygen, siphon pond bottom to remove residues and broken biofilm. |
| Post-harvest | – Use a mix of organic acids + enzymes to clean tanks, ponds, and piping systems. |
Strategy for Controlling and Disrupting Biofilms
To find high-quality probiotics, enzymes, and organic acids, customers can refer to products from Truong Hai Tien Company. If you have any questions about the products, please do not hesitate to contact us. Our technical and sales team will provide detailed support and consultation.
Truong Hai Tien – Specialist supplier of quality products for aquaculture and livestock!
