More Attention Has Been Paid To Antimicrobial Agents In The World.
With the development of society and the improvement of living standards, people's demand for durable consumer goods, such as clothing, sanitary products, daily necessities and commodity packaging, is getting higher and higher. Especially, the use of antibacterial materials in public facilities has become a trend in order to inhibit microbes and prevent the spread of diseases.
The production of antibacterial materials has become a new industry. More and more attention has been paid to antibacterial agents in the world.
Microorganism is the general name of all tiny creatures that can not be seen or seen clearly.
Prokaryotes: bacteria, actinomycetes and mycoplasma, etc.
Eukaryotes: Fungi
(
Yeast, mold
)
And protozoa, etc.
Non cell types: viruses and viroid.
One
Types of antibacterial agents
One
.
One
According to different degrees of inhibition of microbial growth.
Antimicrobial agents are classified into bactericides, disinfectants and bacteriocides according to their degree of inhibition of microbial growth.
Disinfectant, killing all microorganisms in organisms.
(
Including pathogens and non pathogenic bacteria.
)
Propagule and spores.
Disinfectants kill pathogens.
General disinfectants are effective only for the propagation of bacteria under normal concentrations, but no killing effect on spores.
Bacteriostat, also known as bacteriostatic agent or preservative, can prevent or inhibit microbial growth.
Generally speaking, antibacterial agents or antibacterial materials all have bactericidal or bacteriostatic effects.
Many drugs only have bacteriostatic action at low concentration, and can be bactericidal when the concentration increases or the action time is long.
One
.
Two
According to chemical composition
According to chemical composition, antibacterial agents can be broadly classified into two categories: inorganic and organic.
One
.
Two
.
One
Inorganic class
Inorganic antibacterial agent mainly refers to the silver, copper, zinc and other antibacterial or metal ions loaded on inorganic carriers on the carrier, has the advantages of heat resistance, durability, continuity and safety, but there are some shortcomings, such as silver resistance.
In the environment where the concentration of metal ions is relatively high, microbial survival is affected by many factors.
There are mainly two kinds.
1)
Inoculants are weak in mould resistance, high in dosage, high in cost and easy to discoloration.
At present, inorganic antibacterial materials are mainly used in the fields of textile, plastics, coatings and ceramics.
The antibacterial mechanism is that the metal element acts as an antibacterial form in its ionic form. When the metal cation exists outside the microbial membrane, it changes the polarization state inside and outside the normal biofilm, and causes new ion concentration to prevent or destroy the pportation of small molecules and macromolecular substances needed by cells to maintain physiology.
2)
Metal ions that enter cells can also bind to nucleic acids and destroy cell division and reproduction.
There are also photocatalytic antibacterial materials.
At present, photocatalytic antibacterial agents
L3
"
]
There are mainly
TiO2
,
ZnO
,
CdS
,
WOs
,
SnO2
and
Fe2O
。
etc.
N
Type semiconductor metal oxide, in which
Ti02
Its oxidation activity is high, its stability is strong, and it is nontoxic to human body.
TiO
。
Under the irradiation of light, the crystal can completely kill the microorganism in contact with it in a short time. It has the advantages similar to metal ions, which is effective, durable, and has no two pollution.
Its antibacterial mechanism is
TiO
。
The absorption of free radicals by near ultraviolet light can cause oxidation and degradation of organic matter, including penetrating cell membrane, destroying membrane structure, decomposing bacteria, viruses and cancer cells, and degrading the toxin produced by cells.
L2]
。
Because
TiO
。
It can act on organic matter, so its antibacterial spectrum is wider than that of metal ions.
One
.
Two
.
Two
Organic class
Organic antibacterial agents include natural and synthetic two major series.
(1)
Natural class
Natural antimicrobial agents are refined from plants and animals. They come from nature and are rich in natural resources.
People get many kinds of natural antibacterial agents through extraction and purification.
In recent years, with the enhancement of environmental awareness and the rapid improvement of biotechnology research, natural antimicrobial agents have attracted more and more attention.
According to the different sources of natural antimicrobial agents, they can be divided into plant sources, animal sources and microorganism sources.
At present, natural antimicrobial agents and their antibacterial mechanisms are the most natural antibacterial agents.
Its bacteriostatic mechanisms are as follows: secreting antibiotics, participating in the competition of nutrition and living space, inducing host to produce disease resistance.
Microbiologically induced hosts produce defense responses or directly infestate pathogens and inhibit pathogenic bacteria.
The antimicrobial agents of animal origin include amino acids, natural peptides, high molecular carbohydrates and so on, which are rich in resources, and its mechanism is to destroy the peptidoglycan of bacterial cell wall.
P1
,
Four
Glycosidic bond.
Antibacterial properties of Chitosan
Nine
More studies have been done.
Chitosan has strong antibacterial activity. Antibacterial mechanism generally includes two kinds: one is chitosan molecule.
NHs+
With positive electricity, it adsorbs on the cell surface; the other is infiltrating into the cell through osmosis, absorbing the anionic substances in the cell, disrupting the normal physiological activities of the cells, thereby killing the bacteria.
The development of natural food preservatives with strong antibacterial, safe, non-toxic and stable properties is a new research hotspot.
Protamine, chicken yolk immunoglobulin, propolis and lysozyme have wide application prospects in natural preservatives.
The water-soluble chitosan made by Liu Yanru overcomes the defect that it is insoluble in water.
But at present, restricted by production, natural antimicrobial agents can not achieve large-scale market production.
(2)
Synthetic class
The main types of synthetic organic antibacterial agents are quaternary ammonium salts, diguanidines, alcohols, phenols, organometallic, pyridines, imidazoles and thiophenes.
The mechanism of action is mainly to interact with the anion on the cell membrane surface of bacteria and mold, or react with sulfhydryl group, destroy the synthesis system of protein and cell membrane, and inhibit the propagation of bacteria and mold.
The synthetic organic antibacterial agent has the advantages of quick effect, mildew proof effect and long lasting efficacy, but it has the disadvantages of high toxicity and poor heat resistance.
The development of organic antibacterial agents has also made great progress in China.
Donghua University developed the Dow Corning company.
DC_A700
They belong to the same type of antibacterial agents.
CTU
-
I
Its antibacterial properties and
DC5700
Equivalent.
Shanghai Kang post industrial company uses halogenated aromatic compounds and their derivatives as antibacterial agents to produce antibacterial fabrics.
Organic antibacterial agents in foreign markets are mostly organic nitrogen containing compounds, and their structures are similar to antistatic agents, such as organic iodine compounds, organic chloride or their complexes, and metal salts of amino acids.
Organosilicon antibacterial agents used for antibacterial and deodorant in fiber products have been extensively studied in Japan and the United States, representing the products of Dow Corning company.
DC_A700
The trimethoxy silyl group can be well bound with the fibers, while the quaternary ammonium with eighteen alkyl is partially bactericidal.
Its safety is good, but the cost is high.
The so-called mildew proof antibacterial agent is the environment that can inhibit the propagation of bacteria and mold, cause the environment difficult to survive, and the effect can continue for a longer time.
A long time ago, people used various methods to prevent the multiplication of microbes. However, using chemical synthetic agents to make antibacterial materials to prevent the existence and reproduction of microorganisms on fibrous products began in Germany during the two World War, and used quaternary ammonium salts to impregnate military uniforms.
Japan is in
One thousand nine hundred and sixty-five
It began to deodorization and hygienic processing of fiber products in 2008.
Two
Leather antibacterial
Leather products are necessary for human life. With the improvement of people's living standards, the consumption of leather products is increasing.
However, the raw materials used in leather making are rich in protein, fat and other nutrients, which are very easy to be invaded by microorganisms in the process of preservation.
Although processed leather has increased resistance to microorganisms, mildew will still occur, especially in the leather production process, which attracts a large number of fatliquoring agents produced from natural oils. They are also hotbeds for microbial breeding.
In addition, the porous structure and polar structure of leather structure make it easy to absorb moisture and leather is acidic.
All the above reasons constitute the basic condition of moldy.
Mouldy leather products will appear white, blue, yellow and black colonies or patches. The mold on the surface will develop into leather, which will also affect the wearability, strength and elasticity of leather.
Therefore, mould can cause serious damage to the appearance and internal quality of leather and its products. Mould prevention is very important in leather industry.
Because leather is a natural polymer compound.
(
Collagen protein
)
The processed products are suitable for the growth of microbes, especially leather shoes. As the most consumed leather products, they are more conducive to the growth of fungi due to sweat and dust. Therefore, leather products, like textiles and public utilities, need to be endowed with antibacterial properties in order to inhibit the growth of bacteria, fungi and viruses and block the spread of diseases.
In order to prevent the occurrence of mold spots in leather and products, the most effective way is to add mildew proof agents.
There are three kinds of mould inhibitors: inorganic compounds.
(
Including chlorine, chlorine dioxide, etc.
)
Organic compounds such as phenols, alcohols, esters, quaternary ammonium salts, natural preservatives, such as deacetylated chitosan extracted from crabs and shrimp shells, and "bamboo beauty" extracted from bamboo.
Our country used to use pentachlorophenol sodium, ethyl naphthol, sodium arsenite and imported.
PIE
It is used as leather mould inhibitor.
Sodium pentachlorophenol is highly toxic, and it is short of anti mildew period and stimulates skin and skin cancer.
Domestic research on mould inhibitor is in the ascendant.
CJ
One
Eleven
,
A
One
Twenty-six
,
DSS
-
II
Mould inhibitor
B
One
200P
Mould inhibitor
PM
"Jie Mei" brand of leather mould inhibitor, high efficiency mildew proof agent, also used in the following areas: Jing Xiao Li, Fu Mei Bi, Mumei Jing; sterilization Dan, dehydro acetic acid, two thiocyanmethane, paraben ester, and chloro 1.
Three
,
Five
One or two cresol vitamin
K3
,
K4
Bai Yin Qing.
At present, there are commonly used leather mildew inhibitors in Japan.
SannittlOOO (
Organotin compounds
)
,
Bayer
Company
PreventolWB
,
Schill&Seilacher
Company
VinkolWK
,
AfrotinCRO
and
AfrotinE1101
The United States
Angu