4.3.4　Other novel disinfectants

1.Acidic oxidation potential water

Acidic oxidation potential water refers to a disinfectant made by adding a low concentration of sodium chloride solution to water and electrolyzed by electrochemical methods which includes slightly acidic electrolyzed water，weakly acidic electrolyzed water and strong acidic electrolyzed water.At present，it is generally believed that the bactericidal effect of acidic oxidation potential water is determined by its pH value，oxidation-reduction potential（ORP），available chlorine，and active oxygen.The low pH value and high ORP value of acidic oxidation potential water can change the cell membrane potential of microorganisms to enhance their cell permeability，making bacteria swell，destroying inner cell metabolic enzymes，and causing intracellular substances to overflow and dissolve to achieve the bactericidal effect.Acidic oxidation potential water has characteristics of broadspectrum，high-efficiency，non-toxic，non-irritating，non-drug-resistant，but has poor stability and is easily affected by organics and metal ions.

2.Biological disinfectants

Biological disinfectants mainly include plant disinfectants and microbial preparations.Compared with chemical disinfectants，biological disinfectants have characteristics of fast sterilization speed，strong specificity，low toxicity，mild，non-irritating，non-drug-resistant，and no harmful substances remain.The active ingredient is mainly essential oil.Several kinds of botanical extracts（e.g.，vegetable oil，sophora flavescens，chrysanthemum and dried ginger）can be formulated into bactericidal preparations.Microbial preparations have two categories：one is the direct use of microorganisms as bactericides；the other is the separation or synthesis of microbial metabolites.Microbial preparations mainly include bdellovibrio，biological enzymes and bacteriophage.Biological enzymes include lysozyme and staphylococcal enzyme，which have a strong ability to kill Gram-positive bacteria.Lysozyme has been used for disinfection and debridement of burn wounds.The bacteriophage is highly specific and can infect specific bacteria.(https://www.daowen.com)

3.Silver disinfectants

It is Ag+that finally plays the role of sterilization effect in all silver-containing disinfectants.The sterilization mechanisms of Ag+include：combine with the cell membrane to change the original structure and function；act on the proton pump to affect the material transmission and metabolism；combine with thiol，amino and carboxyl groups of intracellular proteins to destroy the structure and function of enzymes that can decompose glucose，sucrose，urea，etc.；combine with DNA to block reproduction and break chemical bonds to destroy the molecular structure.Compared with silver in the form of ions，silver NP is easily contacted with pathogenic microorganisms due to quantum effect，small size effect and a large specific surface area，thereby exerting a greater biological effect.Therefore，silver NP is more secure and durable with stronger antibacterial effect.The sterilization mechanism of silver NP is complex and diverse.As it belongs to non-antibiotic fungicides，it is not easy to develop drug resistance.However，in the setting of lacking protective agents，silver NP materials are prone to aggregate particles and lose nano-characteristics，or are oxidized into brown silver oxide，both affecting its sterilization effect.