Nisin powder,works in synergy with chelating agents to inhibit bacteria

Nisin and chelating agents exhibit significant molecular mechanisms and synergistic antibacterial potential, as follows:

I. Molecular Mechanisms

Disrupting the integrity of the cell membrane: Nisin can act on the bacterial cell membrane. By binding to specific receptors on the cell membrane, it forms pores in the cell membrane, causing the leakage of intracellular substances and thus inhibiting bacterial growth. Chelating agents such as EDTA can bind to metal ions outside the bacterial cell membrane, making the structure of the cell membrane unstable. When Nisin is used in combination with a chelating agent, the chelating agent first disrupts the stability of the cell membrane, increasing its permeability. This makes it easier for Nisin to approach the target on the cell membrane and form more pores, exacerbating the leakage of intracellular substances and enhancing the antibacterial effect.

Enhancing the effect of Nisin: Some Gram-negative bacteria have a certain resistance to Nisin due to the presence of an outer membrane. Chelating agents can remove divalent metal ions such as calcium ions and magnesium ions in the outer membrane of Gram-negative bacteria, which are crucial for maintaining the stability of the outer membrane. After the structure of the outer membrane is damaged, Nisin can more effectively penetrate the outer membrane and reach the cell membrane to exert its antibacterial effect. For example, when EDTA is combined with Nisin, it can change the cell permeability of Gram-negative bacteria such as Escherichia coli, allowing Nisin to enter the cell and inhibit its growth.

Interfering with the synthesis of the cell wall: Nisin can inhibit the synthesis of peptidoglycan in the bacterial cell wall. Chelating agents, by chelating metal ions, may affect the activity of some enzymes required in the synthesis process of the bacterial cell wall, as these enzymes often require metal ions as cofactors. When Nisin acts in conjunction with a chelating agent, on the one hand, Nisin directly acts on the cell wall synthesis pathway, and on the other hand, the chelating agent indirectly interferes with the synthesis of the cell wall by affecting the activity of related enzymes. The synergistic effect of the two further hinders the normal synthesis of the bacterial cell wall, causing bacteria to lose the protection of the cell wall and making them more vulnerable to the external environment and more likely to die.

II. Synergistic Potential

Expanding the antibacterial spectrum: When used alone, Nisin mainly has an inhibitory effect on Gram-positive bacteria. When used in combination with a chelating agent, it can break through the barrier of the outer membrane of Gram-negative bacteria and also inhibit Gram-negative bacteria, thus expanding the antibacterial range. For example, the combined use of Nisin and EDTA can inhibit Gram-negative bacteria such as Escherichia coli and Salmonella, which is of great significance for food preservation and the control of foodborne pathogens.

Reducing the dosage: Due to the enhanced antibacterial effect of the synergistic action, the dosage of both Nisin and the chelating agent can be correspondingly reduced while achieving the same antibacterial effect. This not only reduces the production cost of Nisin but also reduces the potential risks associated with the chelating agent and alleviates the pressure on the environment. For example, when preserving milk, a high concentration of Nisin may be required to effectively inhibit bacterial growth when used alone. However, when combined with an appropriate amount of a chelating agent, the concentration of Nisin can be significantly reduced while still achieving a good preservation effect.

Improving the antibacterial efficiency: The synergistic effect of Nisin and the chelating agent can more quickly inhibit the growth and reproduction of bacteria and shorten the antibacterial time. In some food processing processes, the rapid and effective inhibition of bacterial growth can better ensure the quality and safety of food. For example, in meat processing, the combination of Nisin and a chelating agent can reduce the number of bacteria in a relatively short time and reduce the production of bacterial metabolites, thereby delaying the spoilage of meat.