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Growth medium (배지. Agar, broth) (MacConkey agar, Chocolate agar, VBC, SDA, Mycosel, Thioglycollate broth, Selenite F (SF))

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Growth medium (배지. Agar, broth)

 

Blood agar plate (BAP, 혈액한천배지)

Sheep blood 5-10% 함유.

Enriched, differential media used to isolate fastidious organisms and detect hemolytic activity.

β-Hemolytic activity will show lysis and complete digestion of red blood cell contents surrounding a colony.

Examples include Streptococcus haemolyticus.

α-Hemolysis will only cause partial lysis of the red blood cells (the cell membrane is left intact) and will appear green or brown, due to the conversion of hemoglobin to methemoglobin.

An example of this would be Streptococcus viridans.

γ-Hemolysis (or nonhemolytic) is the term referring to a lack of hemolytic activity.

BAPs also contain meat extract, tryptone, sodium chloride, and agar.

 

MacConkey agar

a selective and differential medium used to differentiate between Gram-negative bacteria while inhibiting the growth of Gram-positive bacteria.

The addition of bile salts and crystal violet to the agar inhibits the growth of most Gram-positive bacteria, making MacConkey agar selective.

Lactose and neutral red are added to differentiate the lactose fermenters, which form pink colonies, from lactose nonfermenters that form clear colonies.

An alternative medium, eosin methylene blue serves a similar purpose.

Bile salts, crystal violet이 포함되어 있는데, 이것이 Gram-positive 세균 증식 억제하고, 그람 음성 세균만 자라게 하는 선택배지.

Neutral red: 지시약 (pH indicator). pH6.8-8.0의 변색 영역. 산성이 되면 붉은색.

Lactose 발효하여 유기산을 생성하면 pH가 산성이 되어 붉은색이 된다.

(유당발효 세균은 붉은색 집락, 발효하지 않는 세균은 무색 집락)

 

Chocolate agar

a type of blood agar plate in which the blood cells have been lysed by heating the cells to 56 °C.

It is used for growing fastidious respiratory bacteria, such as Haemophilus influenzae.

No chocolate is actually contained in the plate; it is named for the coloration only.

RBC를 용해시켜서 RBC 내의 Hb, X factor (hemin), V factor (coenzyme nicotinamide adenine dinucleotide, NAD)를 유리시켜 만든 배지.

Haemophilus spp., Brucella spp., Neisseria spp. 배양에 사용.

 

VBC (Vancomycin Bacitracin Clindamycin) agar

Chocolate 배지에 3가지 항생제 첨가.

H. influenzae 검출률 높이기 위함 (URT flora가 포함된 검체를 Choco에 배양한 경우보다 H. influenza recovery rate 높음

 

Sabouraud Dextrose Agar (SDA)

Selective medium primarily used for the isolation of dermatophytes, other fungi and yeasts but can also grow filamentous bacteria such as Nocardia.

The acidic pH of this medium (pH about 5.0)  inhibits the growth of bacteria but permits the growth of yeasts and most filamentous fungi.

Peptone 함유 (nutrient media for growing bacteria and fungi)

 

Mycosel agar

Mycosel Agar is a highly selective medium containing cycloheximide and chloramphenicol.

It is recommended for the isolation of pathogenic fungi from materials having a large amount of flora of other fungi and bacteria.

 

Broth

Thioglycollate broth




증균배지

(https://microbeonline.com/thioglycollate-broth-principle-composition-preparation-uses/)

 

Selenite F (SF) 액체배지

증균배지.

변 배양에서 Salmonella의 분리율을 높이기 위해 사용



Reference: https://en.wikipedia.org/wiki/Growth_medium

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