What is a Microbivore?

Microorganisms include: a large group of biological groups including bacteria, viruses, fungi, and some small protozoa, microalgae, etc., which are small in size and closely related to humans. It covers a wide range of beneficial and harmful species, including food, medicine, industry and agriculture, environmental protection, sports and many other fields. In Chinese textbooks, microorganisms are divided into the following eight categories: bacteria, viruses, fungi, actinomycetes, rickettsia, mycoplasma, chlamydia, and spirochaete. Some microorganisms are visible to the naked eye, such as mushrooms, ganoderma, and shiitake mushrooms, which are fungi. Microbes are a class of "non-cellular organisms" composed of a few components such as nucleic acids and proteins, but their survival must depend on living cells.

[wi shng wù]
A collective term for all tiny creatures that are difficult for an individual to see with the naked eye. [3]
kind
Prokaryotic;
Eukaryotic:
The largest microorganism currently known in the world: in 1985, Fishelson, Montgomery and Myrberg discovered a microorganism, Epulopiscium fishelsoni, that grows in the small intestine of tropical fish (surgeonfish) growing in red sea It was the largest microorganism found in the world at that time. It looks exactly like
Agricultural microorganisms
Studying the variability, virulence and pathogenicity of microbial pathogens at the molecular level is a revolution for traditional microbiology. Microbial genome research represented by the Human Genome Project has become the forefront of life science research, and microbial genome research is an important branch of it. The world's leading magazine "Science" once ranked microbial genome research as one of the world's major scientific advances. Genome research reveals the genetic mechanism of microorganisms, discovers important functional genes, and develops vaccines based on this. The development of new antiviral, antibacterial, and fungal drugs will effectively control the epidemic of new and old infectious diseases and promote the health of medical services. Rapid development and growth! Genomic research of microorganisms at the molecular level provides new clues and ideas for exploring the mysteries of microbial individual and intergroup interactions. [13]
Before human beings discovered and studied microorganisms, they divided all living things into two distinct worlds-the animal world and the plant world. With the gradual deepening of people's understanding of microorganisms, the two-world system has experienced the three-world system, the four-world system, the five-world system and even the six-world system. Until the late 1970s, Americans Woese and others discovered the third on the earth
In 1989, some experts from several universities and the Department of Energy in the United States
Ecological studies show that the earth is the cradle of all things, including natural ecosystems such as terrestrial ecosystems, water ecosystems, and the atmospheric ecosystem that surrounds the earth. The microorganisms that can survive in the atmospheric environment constitute the atmospheric microbial ecosystem in nature. The atmosphere is divided into troposphere, stratosphere and ionosphere. As the atmosphere rises with height, the temperature drops quickly (the temperature of the troposphere is only -43--83 degrees Celsius), and chemical and physical factors (ozone, microgravity, UV rays, etc.) that are not conducive to life activities are also enhanced, so The only microorganisms in this ecosystem are stress-resistant dormant bodies and dust, mist droplets, animal respiration, and excreta derived from microbial cells or spores. Once microorganisms enter or transcend the ionosphere in the natural ecosystem, it is difficult to survive due to the effects of space environmental factors such as strong radiation formed by galactic rays and geomagnetic trapped radiation and microgravity. Nonetheless, a new science, Exobiology, is being developed to study life beyond Earth, including life on other planets. In this field of research, outer space biologists use various space vehicles (high-altitude balloons, orbiting satellites, space stations, space shuttles, etc.) to explore the response of living organisms to the effects of space environmental factors (ie, biological effects) and conquer humanity. Space provides theoretical knowledge and technical basis, and the main content of Space Biology research: On the other hand, more and more scientists are also trying to recover rocks and dust from other planets including Mars, Moon, Jupiter, etc. Testing of samples to find possible life forms outside the earth. [12]
Biochemical technology
PCR technology
Microorganisms exist in a mixed state in nature, and in order to obtain the required species, they must be separated from them. Inadvertently contaminated bacteria during storage should also be separated. There are many methods for the isolation and purification of microorganisms, but the basic principle is similar. The sample to be separated is diluted to a certain extent, and the cells (or spores) of the microorganisms are kept in a dispersed state as much as possible, and then they are grown into pure species Single colony. However, the above work is inseparable from the process of inoculation, that is, the process of moving one microorganism to another sterilized medium. [10]
Microbial inoculation classification material tool
Constant temperature incubator
2.Vaccination ring, glass rod, straw, alcohol lamp
3. Medium
4.E. coli, Bacillus subtilis, Staphylococcus aureus, yeast, etc.

Microbiological method steps

Vaccination method
Slant inoculation (with Staphylococcus aureus)
(1) Before operation, wipe your hands with 75% alcohol, and light the alcohol lamp after the alcohol evaporates.
(2) Hold the bacteria tube and the bevel between the thumb of the left hand and the other four fingers, so that the bevel and the side with the bacteria are facing up and in a horizontal position.
(3) Rotate the strain and the tampon on the slant surface first, so that it can be easily pulled out during inoculation.
(4) Take the inoculation ring (like holding a pen) with your left hand, first burn the ring end to sterilize with flame, and then extend it into the rest of the test tube and sterilize it.
(5) Use the ring finger, pinky finger and palm of your right hand to pull out the cotton tube and the cotton plug or test tube cap of the oblique interview tube to be connected at the same time, and then let the test tube mouth slowly overheat and sterilize (do not burn or burn).
(6) Extend the burned inoculation loop into the bacteria tube, and contact the inoculation ring on the inner wall of the test tube or the medium without growing moss and let it cool down sufficiently. Then gently scrape a little moss and remove the bacterial Remove the inoculation loop from the seed tube.
(7) Promptly inoculate the inoculation ring with bacteria into another oblique interview tube to be connected. From the bottom of the bevel, make a dense zigzag back and forth. Sometimes it is also possible to use a seeding needle to draw a line only in the center of the medium for slanted inoculation in order to observe the growth characteristics of the bacteria.
(8) After the inoculation is completed, the inoculation ring of the inoculation ring is withdrawn and the cotton plug is plugged.
(9) Sterilize the inoculation ring. Lower the loop and tighten the cotton plug. [10]
Liquid inoculation
(1) The liquid culture medium is connected from the slant culture medium. This method is used to observe the growth characteristics and biochemical reaction of the bacteria. The operation method is the same as before, but the test tube mouth is tilted upwards to prevent the culture fluid from flowing out of the bacteria body. Rub the inoculation ring and the inner wall of the tube a few times to wash the bacteria on the ring. After inoculation, plug the tampon and tap the test tube in the palm of the hand to make the bacteria fully dispersed.
(2) When the liquid medium is inoculated from the liquid medium, when the strain is a liquid, a sterile pipette or a dropper is used in addition to the inoculation ring. When inoculating, just pull out the cotton plug next to the flame, pass the nozzle through the flame, use a sterile pipette to suck the bacteria solution into the culture solution, and shake it. [10]
Plate inoculation
The bacteria were streaked and coated on a plate.
(1) See the separation streak method for streaking inoculation.
(2) Coating and inoculation After sucking the bacterial solution into the plate with a sterile pipette, the surface of the plate is evenly coated with a sterilized glass rod. [10]
Puncture vaccination
Bacteria are inoculated into solid deep culture medium. This method is used for inoculation of anaemic bacteria or for observing physiological performance when identifying bacteria.
(1) The operation method is the same as above, but the inoculation needle used should be straight.
(2) Insert the inoculation needle from the center of the culture medium and pierce it directly to the bottom of the tube, but do not penetrate, and then slowly pull out the original puncture route. [10]
Separation operation method
Dilution separation
The separated sample is dispersed to the minimum by continuous dilution, and then a certain amount is injected into the plate and mixed with an agar medium suitable for melting, so that the dispersed bacteria are fixed in place to form a single colony.
(1) A bacterial suspension is prepared from E. coli or yeast with sterile water.
(2) Take several sterile test tubes, each containing 9ml of sterile water.
(3) Pipette 1ml of the prepared bacterial suspension and place it in the first test tube containing 9ml of sterile water, so that it is diluted 10 times, which is 10-2.
(4) Aspirate 1ml from the first test tube (10-2) and inject it into the second test tube containing sterile water, which will be diluted 100 times, which is 10-2.
(5) Operate in the same way until it is diluted to 10-5-10-6.
(6) Precisely pipette 0.2ml of each of 10-5-10-6 dilutions of bacterial solution into the numbered empty sterile dishes, and repeat the same dilution to three dishes.
(7) Pour the agar medium that has been melted and cooled to 45 ° C into each of the above dishes, gently rotate to fully mix the culture medium and the suspension of bacteria, and then place it in a 37 ° C or 38 ° C incubator after solidification. 24-48 hours, observe the colony growth and distribution on the plate. [10]
Plate scribing
The plate streak separation method is a method for separating microorganisms by dividing the inoculation ring on the surface of the plate culture medium by partitioning. The principle is to dilute the microbial sample "point to line" multiple times on the surface of the solid medium to achieve the purpose of separation.
(1) Invert the plate to dissolve the beef extract peptone agar medium, invert the plate, and leave it to stand horizontally to be coagulated.
(2) Burn the inoculating ring on the flame of alcohol and wait for the cold to take a mixture of Staphylococcus aureus and E. coli.
(3) Hold the agar plate with your left hand slightly lift the lid of the dish, and at the same time near the flame, hold the inoculation ring into the dish with your right hand, and draw a line in the shape of an area on the plate. Gently touch at -40 °, and use the wrist force to make a brisk slide on the surface. Do not scratch or embed the surface of the plate into the base.
(4) Burn the inoculation cup to kill the remaining bacterial solution on the inoculation ring. After cooling, extend the inoculation ring into the dish, and touch it at the place where the line crosses in the first area, and turn it 90 °. , Continue to draw lines in the second area.
(5) After inoculation, burn the inoculation cup. After cooling, use the same method to draw lines in other areas.
(6) After all the lines have been marked, indicate the bacteria, date, group, and name with a special crayon at the bottom of the dish. Place the entire petri dish upside down in a constant temperature incubator.
(7) Take out and observe after incubating at 37 ° C for 24-48 hours. Pay attention to the characteristics of colony switch, size, color, edge, surface structure, transparency, etc. [10]

Microbiological precautions

(1) The inoculation room should be kept clean, scrub the countertops and walls with pulverized coal phenol soap solution, and fumigate regularly with lactic acid or formaldehyde. Before each use, it should be sterilized with a UV lamp. Periodically check the sterility of the inoculation room.
(2) Before entering the vaccination room, do personal hygiene first, and change working shoes, hats, work clothes, and masks in the buffer room. Work clothes, work shoes and masks are only allowed in the vaccination room. Do not wear it to other places, and it must be replaced and disinfected regularly.
(3) The inoculated test tubes, triangles and bottles should be marked with the name and date of the culture medium and bacteria. All items moved into the vaccination room must be wiped clean with 70% alcohol in the buffer room.
(4) Before inoculation, sterilize both hands with 70% alcohol or Xinjieer. Do not leave the flame of the alcohol lamp during operation; tampons should not be placed randomly; flame sterilization is required before and after using the inoculation tool.
(5) The incubator should be cleaned and disinfected frequently. [10]

IN OTHER LANGUAGES

Was this article helpful? Thanks for the feedback Thanks for the feedback

How can we help? How can we help?