Humans are closely related to microorganisms. On the one hand, the right amount or beneficial microbes can give us a lot of favors. Condiments such as alcohol, yoghurt, vinegar and soy sauce, vitamins and antibiotics all benefit from microbes. On the other hand, excessive or pathogenic microorganisms can cause serious health hazards once they invade the human body. The microorganisms we usually refer to are mainly viruses, bacteria, fungi and molds that can adversely affect the human body. The various microorganisms involved in this section are closely related to the fiber products. They are attached to various kinds of fiber products such as underwear and home textiles, causing mildew, discoloration and even serious harm to the human body.

1. Types of microorganisms

Microorganism is a tiny group of organisms that exist in nature and are simple in structure and must be magnified hundreds of times, thousands of times or even tens of thousands of times by optical or electron microscopy.

Microorganisms can be divided into three categories according to structure and composition, including bacteria belonging to prokaryotic species, actinomycetes, mycoplasma, rickettsia, chlamydia and cyanobacteria (formerly known as cyanobacteria or blue-green algae), belonging to eukaryotes. Fungi (yeast and mold), protozoa and microalgae, as well as viruses, viroids and prions belonging to non-cellular types.

1) Bacteria

Bacteria are single-celled protozoa that grow very rapidly under warm and humid conditions. In addition, subgenus of the broad class of bacteria include Gram-positive bacteria (eg, Aureus genus), Gram-negative bacteria (eg, E. coli). Some bacterial types are pathogenic and cause cross-infection.

2) Fungi and mold

Fungi and mold are complex microorganisms that grow relatively slowly. They stain the fibers and can affect the appearance of the fabric. pH 6.5 is the optimum pH for fungal growth.

3) Algae

Algae are a class of multicellular microbes whose growth depends on continuous water and sunlight. It can grow on fabrics and form dark spots on the fabric. The optimum pH for algae growth ranges from 7.0 to 8.0.

4) Virus

A virus is a non-cellular organism whose core is made up of nucleic acids and the outside is tightly packed by protein shells. The genetic information of the virus is stored in the nucleic acid, which controls the inheritance, variation, reproduction and infectivity of the virus. Since the virus is an obligate parasite, it must pass through the adsorption to enter the host cell in order to survive and self-replicate. The attack of human viruses has its particularity and harmfulness, such as foot-and-mouth disease virus, hepatitis virus, influenza virus, SARS virus and so on. [4]

At present, antibacterial has formed a relatively mature industry, but in conquering infectious virus, it has always been an important issue that needs to be solved urgently in modern medical and health development. In this chapter, special sections will be used to discuss antiviral finishing and antiviral textiles.

2, the harm of microorganisms

Human skin is a good medium compared to nature. In general, on the surface of human skin, the number of normal bacteria and fungi is 100-2000 per square centimeter. Within this quantity range, they do not endanger human health and do not produce odors. Not only that, but some resident bacteria on the skin can also protect the skin from the harmful effects of pathogenic microorganisms. However, when the ambient temperature is high, the flora in the microorganisms is dysregulated, and a small number of pathogenic bacteria in them will rapidly multiply in a geometric manner, 1, 2, 4, 16, 256, etc., usually every 20 minutes. Breeding once, so within 8 hours, a bacterium can breed 1.6 million offspring. [5] and these bacteria and fungi spread through the skin, respiratory tract, digestive tract and genital mucosa, causing harm to the human body.

Common problems caused by microorganisms are mainly the following:

1) The proliferation of bacteria and fungi can cause odor and pollution problems

The breeding of bacteria and fungi requires three basic elements: nutrition, proper temperature and humidity. Most of the human and human life have these three conditions, so bacteria and fungi can grow and reproduce under suitable conditions.

Typical odors such as sweat odor, odor, and foot odor are caused by microorganisms that multiply in warm and humid environments. Microorganisms absorb nutrients from human skin secretions and sweat, and produce a pungent smell through metabolism.

We take the freshly washed clothes or bedding as an example, and should be clean and hygienic by daily standards. A clean body put on clean clothes and started a day of life. However, the clothes, the body and the air we breathe are not disinfected and contain some normal flora. In the next 8-12 hours, our body will sweat (which contains nutrients) and maintain a certain temperature. Most of the moisture and heat are lost to the atmosphere through clothing. Our skin and clothing provide an ideal environment for fungal/bacterial growth. Textiles are always an important medium in the propagation and spread of pathogenic bacteria. These clothes are contaminated with a lot of sweat, sebum and various other human secretions, and are also contaminated by dirt in the environment. After 8-12 hours of work, the amount of bacteria/fungi that absorbs a lot of nutrients increases dramatically, which leads to the production of odor.

For example, in the lifestyle of the staff, I leave home at 8 am and get off work at 5 pm, during which time it is 9 hours. In the case of shoes, if the moderate environment is reached, the number of bacteria in the shoes can be increased to more than 100,000 times. . In contrast to Figure 1, the body produces malodorous gases around noon, or about 4 hours. In the range of value-added curves 3 and 4, that is, in about 9 hours, there is no doubt that stench will occur. This is consistent with the experience of many people in their daily lives.

Figure 1. Breeding curve of bacteria

Even with daily washing, bacterial reproduction still causes many adverse conditions during the day. This can happen even if the socks and underwear are washed every day, not to mention the textiles that are less frequently washed, such as pajamas, sheets, and tweezers. In addition, clothes such as sweatshirts that are worn in a lot of sweating occasions, the bacteria multiply in a short time, and produce a lot of odors, resulting in an unpleasant mood. Antibacterial hygiene finishing can at least alleviate the unpleasantness caused by bad odor in people's daily life.

2) The proliferation of fungi causes mold and bath fungus infection in Hong Kong feet and bathrooms.

Fungi are widely distributed in nature, with more than 100,000 species. There are about 270 kinds of fungi known to cause human diseases, which cause various manifestations of diseases. Shallow fungi can invade hair, fingers and skin, while deep fungi can invade heart and liver. Spleen, lung, kidney, brain, blood, gastrointestinal, bone and other organs and systems, high mortality.

The proliferation of fungi causes a variety of skin diseases, and can cause mildew in bathrooms, mattresses, walls, and the like. This is because the growth of fungi requires a mild and humid environment. China's coastal areas and most of the inland areas are such climates. With the global warming effect and the increasing number of homes equipped with air conditioning, the temperature of the living room is suitable for fungal growth all year round. Another important reason is that most of the popular home textiles such as bedding are natural fiber products. For example, cotton fiber is more susceptible to microbes than chemical fiber, because the porous structure of cotton fiber can retain a large amount of water. , oxygen and nutrients, which provide a good environment for the growth of fungi.

In addition, fungi are slower to breed than bacteria, but are not easily washed away. Because they are resistant to ordinary washing, it is difficult to eradicate.

3. The common microorganisms that cause harm to the human body mainly include the following types:

1) Shigella

It is a Gram-negative, aerobic, spore-free, non-motivated bacterium. It is a pathogen causing bacterial dysentery in humans. Many outbreaks of bacterial dysentery are caused by contaminated food, milk and water. The bacterium belongs to a small dose of bacteria, and 10 bacteria can produce symptoms. When the concentration of bacteria is not high, it may cause infection in the population.

2) Escherichia and Enterobacter

The Escherichia bacterium that lives in the intestines of humans and animals is a Gram-negative bacillus and is an important spoilage organism in food. Both Escherichia and Enterobacter belong to the coliform group. E. coli is one of the major causes of diarrhea in infants. Pathogenic E. coli can cause human food poisoning.

The shape of the bacterium is rod-shaped, with flagella around the body, and it can move. It often enters the intestines after birth or a few hours after the animal is born. In addition to certain strains that produce enterotoxin, which causes gastroenteritis, it is generally not pathogenic. E. coli can synthesize vitamin B and vitamin K which are beneficial to the human body, but when the resistance of human or animal body declines or E. coli invades other parts of the human body, it can cause peritonitis, sepsis, cholecystitis, cystitis and diarrhea.

3) Salmonella

Salmonella is a group of Gram-negative bacilli with similar antigenic structures and biological characteristics. There are two types of infections of the human body by Salmonella. One is typhoid and paratyphoid caused by typhoid and paratyphoid bacillus, and these pathogenic bacteria are only pathogenic to humans. The other is acute gastroenteritis with fever symptoms caused by various Salmonella, such as food poisoning.

For many Salmonella, humans and a variety of animals have susceptibility, mainly through the digestive tract infection. Once infected, the human body can cause serious diseases such as typhoid fever, paratyphoid fever, food poisoning and sepsis. The pathogenic cause of Salmonella is the bacteria themselves, and the second is the toxins they produce. The disease caused by toxins is called food poisoning. After ingesting the toxin, the incubation period is very short, and it can be ill within a few hours. It is fierce, but it recovers quickly. The disease caused by bacteria has a long incubation period. It usually takes 3-4 days to start slowly, and the fever takes a long time. In addition to invading the stomach and intestines, it can also invade other organs, causing sepsis.

4) Pseudomonas

For Gram-negative Bacillus, aerobic or facultative anaerobic, single or hairy, motivated. The vast majority are attenuated or non-toxic bacteria, and only a part of them are pathogenic bacteria. It is widely distributed in nature, and is commonly found in soil, water, utensils, clothing, animal and plant surface, and various protein-containing foods. There are many kinds of bacteria in this genus, reaching more than 200 species. Only the Pseudomonas aeruginosa closely related to people's lives will be introduced below.

Pseudomonas aeruginosa can produce a variety of virulence-related substances, such as endotoxin, exotoxin A, elastase, collagenase, pancreatic peptidase, etc., among which exotoxin A is the most important. Pseudomonas aeruginosa infection can occur in any part of the body and tissues, common in burns or wounds, in the middle ear, cornea, urethra and respiratory tract. It can also cause endocarditis, gastroenteritis, empyema or even sepsis.

5) Micrococcus and Staphylococcus

It is a Gram-positive cocci. Individual, paired, irregular masses or piles. Usually no power, no spores are formed. Some bacteria can grow in low temperature environments, causing spoilage of frozen foods. Some strains produce pigments, and here mainly introduces Staphylococcus aureus.

After the human body is infected with Staphylococcus aureus, in a short period of time (about 1-8 hours, an average of 3 hours), enterotoxin is produced, causing food poisoning symptoms. The main symptoms are: vomiting (must occur), diarrhea, diarrhea, abdominal pain, collapse, most of them will not have fever. Symptoms last for 24 hours to several days, and the mortality rate is almost zero, but it is a threat to patients and the elderly.

6) Streptococcus

For Gram-positive cocci, they are arranged in short or long chains. No spores, no flagella, most without capsules. Aerobic or facultative anaerobic. Poor growth on common media.

Streptococcus type A is the most common type of streptococcus. In the United States, it causes 10 million cases of streptococcal laryngitis and mild skin infection every year. Streptococcal laryngitis can cause rheumatic fever or even rheumatic heart disease without treatment. There are 12 million people with rheumatic heart disease worldwide, and 400,000 people die each year, mostly in developing countries. The most severe Streptococcal A infection is a relatively rare streptococcal necrotizing fasciitis, commonly known as carnivorous disease, and toxic shock syndrome.

7) Candida albicans

Candida albicans is a fungus that is susceptible to humans. Once the infectious bacteria of Candida albicans invade the digestive system, the healthy microbial system will be disordered, nutrient absorption will be limited, and the immune system will be seriously damaged. The disease caused by Candida albicans is mainly thrush. This disease usually occurs in infants with unclean mouth and malnutrition, and can also occur in frail adults, mainly due to the low natural resistance of chronic diseases, or the long-term use of antibiotics to cause bacteria in the mouth. The group is out of tune, the natural balance of the microbes is disturbed, and the fungus will grow out of control.

[China Antibacterial Fabric Network ]