Experiment on the preparation of blood agar medium
Experiment on the preparation of blood agar medium
Blood medium is a kind of beef paste peptone medium containing defibrillated animal blood (usually rabbit blood or sheep blood), so in addition to the various nutrients needed for the culture of bacteria, it can also provide coenzymes (such as factor V), hemoglobin (factor X) and other special growth factors. Therefore, blood culture medium is often used in the culture, isolation and preservation of certain pathogenic microorganisms with harsh nutritional requirements. In addition, this medium can also be used to determine the hemolytic effect of bacteria.
Operation method
Preparation of blood agar medium
Principle
Blood medium is a kind of beef paste peptone medium containing defibrillated animal blood (usually rabbit blood or sheep blood), so in addition to the various nutrients needed for the culture of bacteria, it can also provide coenzymes (such as factor V), hemoglobin (factor X) and other special growth factors. Therefore, blood culture medium is often used in the culture, isolation and preservation of certain pathogenic microorganisms with harsh nutritional requirements. In addition, this medium can also be used to determine the hemolytic effect of bacteria.
Materials and Instruments
Rabbit Sheep Move I. Blood culture medium formulations For more product details, please visit Aladdin Scientific website.
Beef Paste Peptone Medium
Triangular flasks Petri dishes Syringes
II. Equipment
1. Culture media
Beef paste peptone medium.
2. Instruments or other paraphernalia
Sterile triangular vials containing 5-10 glass beads, sterile syringes, bloodless flatware, etc.
3. Animals
Healthy rabbit or sheep.
III. Operational steps
1. Preparation of Beef Paste Peptone Agar Medium (see experiment) Beef paste peptone medium ).2. Preparation of sterile defibrinated rabbit (or sheep) blood
Use a syringe equipped with an 18-gauge needle to aseptically extract whole blood (see injection of experimental animals for aseptic blood collection), and immediately inject it into a sterile triangular vial containing sterile glass beads (about 3 mm), and then shake the triangular vial for about 10 min, and the fibrin clumps formed will be deposited on the glass beads, and then pour the supernatant containing blood cells and serum into the aseptic container, that is to say, we get the defibrinated rabbit blood (or goat blood) and put it in the refrigerator. Keep it in refrigerator.
The whole process must be strictly aseptic, when preparing defibrillated blood, it should be shaken for enough time to prevent coagulation.3. Dissolve the beef paste peptone agar medium and leave it to cool to 45 ℃, then aseptically add 10% sterile defibrinated rabbit blood (or sheep blood) to the medium, and shake immediately so that the blood and the medium are well mixed.
The addition of blood at 35-45 ℃ is to preserve some of the heat-resistant nutrients and to preserve the integrity of the blood cells so as to facilitate the observation of bacterial hemolysis. At the same time, the agar does not coagulate at this temperature.4. Pour quickly and aseptically into a sterile flat dish to make a blood agar plate. Be careful not to create air bubbles.
5. Leave at 37°C overnight and use if sterile.