Common bacterial culture preparation

diagnosis of infectious diseases lies in the isolation and identification of pathogens, artificial
ceditation
method provides bacteria with the necessary conditions for growth, so that they grow and reproduce in-body. This chapter focuses on the preparation of commonly used bacteria
fultural base
, the method of inoculation of bacteria and the identification of
national and chemical
reactions, and finally introduces the detection of endotoxins. Students are required to understand the principles and methods of the production of culture, and master the separation and culture technology of bacteria.
is a product that provides nutrients necessary for bacteria to grow and reproduce when they are artificially cultured. The nutrients contained in the basic culture can meet the nitrogen sources, carbon sources and inorganic salts needed for the growth and reproduction of common pathogens. Adding some special ingredients (e.g. sugars, blood, inhibitors, etc.) to the base culture base can be made into nutritional culture, identifying the culture base and selecting the culture base.(i) Broth culture base
Broth culture is a commonly used liquid culture base, but also the preparation of commonly used bacterial separation culture and some other cultures.

fresh beef (de-fat and tendon), protein , sodium chloride, pH
test paper
, 10% sodium bicarbonate,
test tube
, triangular burners, distilled water, etc.
Method:
1. Cut or crush 500g of fresh beef, add water to 1000ml, soak overnight in a 4C fridge or cold place, then boil 30min, cool, so that the remaining fat solidifies, and then use a velvet or filter
filter
, fill the filter to the original amount. This solution is called meat water or meat immersion.
2． 1000ml of meat water with protein10g, sodium chloride 5g,
heating
dissolve and cool.
3． The acidity and alkalinity were measured with precision pH test paper, and the pH was about 7.2 with 10% sodium bicarbonate. When over-alkali, it can be corrected with 10% acetic acid.
4． Packed in test tubes or triangulation bottles, 15 pounds (121 degrees C) of high-pressure vapor sterilization 20 to 30min.
such as the use of commercially available beef paste instead of fresh meat, beef paste can be dissolved into 0.3 to 0.5% of the aqueous solution, and then as the rule of law into a culture base.(ii) Ordinary
gascide
Fase
Common agar cultures are commonly used solid cultures, including ordinary agar plates and ordinary agar slopes, the former for the separation of pure bacteria, the latter for the proliferation of purebred bacteria or the preservation of strains.

(1) Meat water 200ml
(2) protein2g
(3) sodium chloride 1g
(4) agar 5g
(5) sterile flat dish, sterilized test tube, triangular bottle, etc.
Method:
1. Put the meat, protein, sodium chlorideagar in a triangular can, and heat it to melt, according to the quantity noted above.
2． The acidity and alkalinity were measured with pH test paper while hot, and the pH was corrected with 10% sodium bicarbonate to be about 7.2.
3． 15 pounds of high-pressure vapor sterilization 20 to 30min.
4． Pour the dissolved culture base into the sterilized flat dish while it is hot, pour each flat dish into about 15 ml, solidify it into a normal agar plate culture base, if the culture base is poured into the sterilization test tube while hot, and then tilt the test tube into the test bench, solidified into a normal agar slope culture base.
, a polysaccharide extracted from seaweed, commonly known as ocean powder, has the characteristics of melting at 100 degrees C and solidified at 40 degrees C. Bacteria can not break down agar, so there is no nutritional effect, only solid culture base of the shape agent.
common agar media can also be prepared using commercially available nutritional agar powder (containing various ingredients of ordinary agar media and pH) for use in the product description.(iii) Blood agar culture
some bacteria have higher nutritional requirements, poor growth on ordinary agar culture, can be cultured with blood agar culture.
(material)
(1) ordinary agar culture base 200ml
(2) blood (defibreed sheep blood or rabbit blood) 10 to 20ml
method
1. Heating dissolves ordinary agar mediums.
2． When cold to about 50 degrees C, add sterile defiber blood and mix well (take care not to foam).
3． It is divided into sterilized test tubes or flat dishes to make a blood ramp and plate culture medium.