Application Status of Fungicide

fungicides can be divided into inorganic fungicides (such as chlorine dioxide, sodium hypochlorite) and organic fungicides (such as chlorophenols, quaternary ammonium salts) according to chemical composition; according to the mechanism of killing agents can be divided into oxidized fungicide (chlorine, sodium hypochlorite ) And non-oxidizing fungicides (chlorophenols and their derivatives, quaternary ammonium salts, etc.).

All fungicidal mechanism can be summarized as followed:

     (1) Impede the respiratory activity of the cells, inhibit the activity of respiratory enzymes to                     interrupt the energy metabolism or reduce it.

     (2) Inhibit the synthesis of protein , inhibit the activity of various enzymes, RNA, amino acids and           other substances to destroy the protein synthesis or destroy the water film of protein to                    inactivate the protein.

     (3) Destroy the cell wall (membrane), to break its internal and external balance.

     (4) Hinder nucleic acid synthesis, inhibit the corresponding enzymes, DNA, RNA and so on to                 destroy the growth and reproduction of bacteria. A wide variety of fungicides, the mechanism           is different, with one of the above conditions can make bacteria be inhibited or lethal.

According to its effects, surfactants, especially cationic and zwitterionic quaternary ammonium compounds, are one of the most widely used fungicides in the field, such as dodecyltrimethyl Ammonium chloride, dodecyldimethylbenzylammonium chloride,dodecyldimethylbenzylammonium bromide, polymeric quaternary ammonium salts and so on.

Quaternary ammonium salts are cationic surfactants. In addition to a strong bactericidal effect, quaternary ammonium compounds also have a strong sludge peeling effect, which can kill the anaerobic SRB grown below the slime. Due to strong chelating ability, when used with other agents it may have a synergistic effect. It can be described as a multi-performance treatment agent.

However, the long-term using of DDBAC/BKC（1227） and other fungicides will play a role in the sorting of microorganisms. As a result, the sterilization efficiency will decrease, and the dosage of pharmaceuticals will be increased. The price of quaternary ammonium salt fungicide is not so cheap, thus the cost will increase. In a addition, such kind of fungicides is easy to foam, in the case of high water hardness will also reduce its bactericidal effect. Therefore, the development of new fungicides is imperative.