Lactic acid bacteria can not block the growth and reproduction of Vibrio in aquaculture.

Teng's Fisheries Business Network-exclusive report by Contemporary Aquatic Magazine:

Lactic acid bacteria are a kind of non-spore and gram-positive bacteria that ferment sugars and the main products are lactic acid. All bacteria that can produce lactic acid from glucose or lactose fermentation are called lactic acid bacteria. Lactic acid bacteria is a very complex group of bacteria, which can be divided into at least 18 genera and more than 200 species.

1. Types

Although there are many properties and types of lactic acid bacteria, we can clearly divide lactic acid bacteria into two categories from their sources:

(1) Lactic acid bacteria of animal origin

Taken from animals, because the bacteria are often in a relatively unstable state, its biological efficacy is also unstable, and when eaten in large quantities, it is easy to lead to human animal protein allergy, that is, rejection.

(2) botanical lactic acid bacteria

Because the plant is easy to be absorbed by the human body, no matter how much it is ingested, the human body will not produce allogeneic protein rejection, and the plant-derived lactic acid bacteria are more active than those of animal origin and can be colonized in the human small intestine 8 times more than that of animal sources. in order to play its strong and stable biological effect.

Human beings have been using lactic acid bacteria since 5000 years ago, and the application of lactic acid bacteria is not discovered by modern people.

2. Functional characteristics

A good microbial ecological preparation produced by lactic acid bacteria is applied to aquaculture. Its main functions are to change the composition of intestinal flora of aquatic organisms, improve gastrointestinal function, maintain the balance of intestinal flora, and form an antibacterial biological barrier.

What do you mean by blocking? Interrupting the progress or progress of (something) because of a substance is called blocking.

What is a blocking drug? Blocking drugs refer to the substrates or competitive inhibitors that the virus plays a leading role in the process of transcription, thus preventing virus replication. These drugs are mainly divided into the following five categories. (1) nuclides. The main treatment of immunodeficiency disease and related syndrome, there are serious adverse reactions, need long-term or lifelong medication. (3) protease inhibitors. (4) invasive inhibitors. (5) integrase inhibitor.

At present, there are few drugs for blocking therapy in both humans and animals, and the drugs used for blocking therapy are used for viruses, not bacteria. The drugs used to block DNA synthesis of bacteria are antibiotics. However, lactic acid bacteria and their metabolites do not block the growth and reproduction of Vibrio in aquaculture water or aquatic products.

3. The principle of action

The principle that lactic acid bacteria can play a role in aquatic animals is biological antagonism and has no function of blocking the growth and reproduction of Vibrio.

What is biological antagonism? Biological antagonism refers to the struggle between microorganisms to resist each other, repel each other, compete with each other for living space and conditions, and even kill each other. A stable and biologically balanced normal microflora has obvious bioantagonistic effect on foreign bacteria in aquaculture water and aquatic products. The cause of biological antagonism is the role of microorganisms and a variety of secretory substances produced by them, among which anaerobes play an important role.

Biological antagonism has the following forms:

The main results are as follows: (1) change the culture water body and aquatic microenvironment. The organic acid produced in the process of bacterial growth reduces the pH value of culture water and aquatic biological environment, inhibits foreign bacteria, promotes intestinal peristalsis and removes foreign bacteria.

(2) occupying space. Bacteria closely combine with the mucosal epithelial cells of aquatic organisms to form "space occupying" protection (biological barrier), thus repelling foreign bacteria.

(3) Nutrition contention. Due to the large number of anaerobes (mostly beneficial bacteria) in their specific aquatic biological environment, they have an advantage in competing for nutrition with foreign bacteria, thus limiting the growth and reproduction of foreign bacteria.

(4) secreting antibacterial substances. In the process of biological fermentation, the role of antibacterial substances produced by microorganisms is very important, which has a strong inhibition and lethality to foreign bacteria.

(5) immunity. The combination of normal microbiota and host immunity can also produce very effective biological antagonism.

4. Application of lactic acid bacteria in aquaculture.

Lactic acid bacteria are a large class of bacteria used by human as food microorganisms, especially in enhancing the health function of milk, improving the quality of silage, improving the production performance of livestock and poultry, and reducing the effect of animal product storage on meat flavor. It is widely used in food, medicine, light industry and animal husbandry and other fields.

At present, the reports on lactic acid bacteria in aquatic products mainly focus on the habitat of lactic acid bacteria in the intestines, stomach and other visceral organs of aquatic animals. Lactic acid bacteria are widely used in aquaculture, mainly mixed with feed to feed animals, or as the dominant bacteria of EM bacteria to sprinkle in the water.

Put lactic acid bacteria into the aquaculture water body to improve the aquaculture water environment, inhibit the reproduction and growth of harmful bacteria in the water body, adjust the balance of algae, and control harmful bacteria and algae.

No matter from the functional characteristics of lactic acid bacteria or the principle of action, it is proved that lactic acid bacteria can not block the growth and reproduction of Vibrio in aquaculture water or aquatic organisms.

This article is selected from the March 2015 issue of Contemporary Aquatic products. The article is an exclusive report of Teng's Aquatic Business Network. Reprint please mark the source, violators will be investigated for legal liability, thank you for your cooperation.