Micro-organisms-microbicides

Antimicrobial substances will be referred to in this book as microbicides in as far as they kill micro-organisms and as microbistats in as far as they inhibit the multiplication of micro-organisms. Whether the action of a substance is microbicidal or microbistatic generally depends on the concentration at which the substance is used. 

The experts are fully conversant with these distinctions and take them for granted. Whenever appropriate, however, the same distinctions should be used more widely — not simply to prevent confusion, but also so that the general public is constantly reminded that modem active ingredients and those undergoing development are not intended to attack the entire bios , but only a limited part of it. Their effects — in other words — are specific microbicides, for example, are active only against micro-organisms. 

Anionic and non-ionic surface active compounds are not important as microbicides for the protection of materials. On the contrary, aqueous anionic or nonionic detergent solutions need the addition of in-tank/in-can preservatives for protection against contamination and proliferation of micro-organisms. 

Antibiotics may be defined as secondary metabolites of micro-organisms. In contrary to primary metabolites (proteins, carbohydrates, nucleic acids, lipids) which play an essential role in the growth and multiplication of cells secondary metabolites are of no importance in that respect. Antibiotics dispose of a relative low molecular mass and the ability to exhibit microbistatic or microbicidal efficacy in/on other microbe species by impairing the cell wall biosynthesis, the cytoplasmic membrane, the oxidative phophorylation. Because of there extremely high antimicrobial activity antibiotics are mainly used as chemotherapeuticals however, some antibiotics are also used in the food industry for the protection of food against deterioration e.g. Nisin (20.11.1.), Pimaricin (20.11.2.). But these applications will be more and more restricted or even completely banned as microbes may acquire resistance which represents a severe problem in chemotherapy with antibiotics. Acquired resistance is a consequence of the selection pressure on a microbe population in the presence of microbicides. Chemotherapy with an antibiotic the application of which has led to the selection of mutant resistant organisms is no longer successful. 

Masahiro, M. and Katsuhisa, I., 2000. Synergistic industrial microbicidal compositions containing 2,2-dibromo-2-nitroacetamide and control of micro-organisms. IP 2000044406. 

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