The artificial culture procedures of bacteria are briefly described and the commonly used artificial

The artificial culture procedure of bacteria is as follows: specimens (specimens with small estimated bacterial load, first increase bacterial culture) According to the purpose of culture, inoculate in an appropriate medium and a suitable culture environment, observe the growth of bacteria for 35 -37 and 18-24 hours, and select suspicious colonies for isolation and identification. According to the demand for gas, the artificial culture methods of bacteria can be divided into:

1. Aerobic culture (aerobic bacteria and facultative anaerobic bacteria): it can be placed in the air, which is suitable for most bacteria; 2. Anaerobic culture (obligate anaerobic bacteria): it needs to be cultivated in an environment without free oxygen; 3. Carbon dioxide culture (a few bacteria such as Neisseria meningitidis, Brucella, Campylobacter jejuni, etc.):

It needs to be cultivated in an environment containing 5%-10; 4. Microaerophilic environment (culture of bacteria that can grow only in an environment with a low oxygen pressure of about 5%).

For some bacteria that are valuable to our scientific research, they are generally cultivated and preserved by artificial methods. So, how do you grow bacteria correctly? Different bacteria require different nutrient conditions and culture environments.

Some bacteria prefer an acidic environment, some prefer an alkaline environment, some bacteria can survive with sufficient oxygen, and some need an anaerobic environment. However, the medium used to grow bacteria requires sufficient water and is mostly incubated at a temperature of 37 degrees Celsius. Typical bacteria can live on a medium with moderate acidity and alkalinity for about a week.

When the medium dries or nutrients are depleted, the bacteria become dormant or die. Add a certain proportion of antifreeze to the culture medium and put the bacteria in the refrigerator at about minus 70 degrees Celsius to store the bacteria for a long time.

Different media have different preparation methods, which generally include the following steps:

1) Accurate weighing reagents According to different fungi and uses, choose the appropriate medium, and the reagents required for the medium must be pure.

2) Correct the pH value, put the various components of the weighed medium into the container, mark the line, heat and dissolve, replenish water, measure the pH, and measure the pH of the precision test strip or acidity meter. Adjust the pH to the appropriate range with 1nNaOH and 1nHCl.

3) Filter: Place the glass funnel on an iron frame, then put cotton with gauze or filter paper in the funnel, and pour the above medium into it and filter it until transparent.

4) Divide the filtered medium into a medium test tube or triangular bottle (5ml per tube; 100 150ml in a triangular bottle), plug the tampon and wrap it with kraft paper, and prepare it for sterilization.

5) Sterilization of sterilization medium, commonly used autoclave sterilization method. Generally, the vegetative cells of microorganisms are killed after boiling in water, but the spores of bacteria have strong heat resistance and must be sterilized by autoclaving to achieve the purpose of complete sterilization. According to the principle that the temperature of steam rises with the increase of pressure, that is, the higher the pressure, the higher the temperature of the steam.

Therefore, under the same temperature conditions, the use of autoclave sterilization is more effective than dry heat sterilization. Moreover, in the case of damp heat, after the bacteria absorb water, its protein is easy to coagulate and denature, because the penetration of steam is strong, and the sterilization effect is good.

After the first culture of the secretion, pick out the suspicious colonies, one ring is enough, and then inoculate to a new medium and then culture, this is the isolation and purification process of bacteria, that is, pure culture, the whole process must pay attention to aseptic operation, when selecting the colonies, we must pay attention to distinguish from miscellaneous bacteria.

Many bacteria cannot be cultured. Bacteria that can be cultured need to check its medium recipe and the conditions under which it is cultured. Viruses generally exist as binary cultures, i.e., infection susceptible bacteria. Of course, there are many that cannot be cultivated.

The general procedures for preparing culture media include: weighing, heating, dissolving, pH adjustment, filtration, guessing old sterilization, and aliquoting. Spike liters.

According to the use of Zhenghuai, it can be divided into basic medium, nutrient medium, identification medium, selection medium and anaerobic medium.

The life of bacteria and fungi requires certain conditions, such as moisture, suitable temperature, and organic matter Therefore, the first thing to prepare is to prepare a medium containing nutrients, you can use beef Chunhui juice and agar to boil, and then sterilize the medium and all utensils at high temperature after rough attack to prevent miscellaneous bacteria from interfering with the experiment, in order to prevent high temperature from killing bacteria and fungi, wait for cooling, and then inoculate, and put it in a warm place for constant temperature culture after inoculation Note: Observe regularly and record the experimental phenomenon in detail

In a sterile state, the process of putting the bacteria or fungi to be cultivated on the culture medium is called inoculation

So the answer is: vaccination

General methods and experimental procedures for culturing bacteria and fungi: (1) To prepare the medium, the medium containing the nutrient return material should be prepared first, and the bacteria should be born.

Answer: Nutrients are needed for living, not agar, which is a substance that can gelatinize into a solid after boiling and cooling, so A is not in line with the topic

2) High temperature sterilization, sterilization of the prepared medium and Petri dishes to prevent the invasion of other bacteria from affecting the experiment

3) Inoculate it after cooling, so c does not fit the topic

4) Cultivated in an incubator, the bacteria multiply faster in a place with a suitable temperature Note: Observe regularly and record in detail in the group So a does not fit the topic

Therefore, a

The general method and experimental procedure for culturing bacteria and eubais: (1) To prepare the medium, first of all, it is necessary to configure the DAO containing the camp.

The medium capacity of the nutrient substance, the reason is that the life of bacteria needs nutrients, not agar, which is a substance that can gelatinize into a solid after boiling and cooling, so a does not fit the topic

2) High temperature sterilization, sterilization of the prepared medium and Petri dishes to prevent the invasion of other bacteria from affecting the experiment

3) Inoculate it after cooling, so c does not fit the topic

4) Cultivated in an incubator, the bacteria multiply faster in a place with a suitable temperature Note: Observe regularly and record in detail so a does not meet the meaning of the topic Therefore, choose: a

1.Configure the medium.

2.High temperature sterilization.

3.Inoculate after cooling.

4.Isothermal culture.