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现货|Desoxycholate Lactose Agar|脱氧胆酸乳糖琼脂
用途：
Desoxycholate Lactose Agar is a slightly selective and differential
plating medium used for isolating and differentiating gram-
negative enteric bacilli and for enumerating coliforms from
water, wastewater, milk and dairy products.
原理：
Peptone provides nitrogen and carbon for general growth
requirements. Lactose is a fermentable carbohydrate. Sodium
chloride maintains the osmotic balance of the medium.
Sodium desoxycholate and sodium citrate inhibit growth of
gram-positive bacteria. Neutral red is a pH indicator. Agar is
the solidifying agent.
Differentiation of enteric bacilli is based on fermentation of
lactose. Bacteria that ferment lactose produce acid and, in
the presence of neutral red, form red colonies. Bacteria that
do not ferment lactose form colorless colonies. The majority
of normal intestinal bacteria ferment lactose (red colonies)
while Salmonella and Shigella species do not ferment lactose
(colorless colonies). |