|
Casein Nutrient Agar
Casein nutrient agar (CN) is a growth medium used to culture isolates of lactic acid bacteria such as ''Streptococcus thermophilus'' and ''Lactobacillus bulgaricus ''Lactobacillus delbrueckii'' subsp. ''bulgaricus'' (until 2014 known as ''Lactobacillus bulgaricus'') is one of over 200 published species in the ''Lactobacillus'' genome complex (LGC) and is the main bacterium used for the production of yogurt. ...''. It is composed of standard nutrient agar with the added ingredient of skim milk powder, which contains casein. Lactic Acid Bacteria will precipitate casein out of the agar by lowering the pH. This will produce a cloudy appearance around the colonies that do this. This medium is not regarded as selective as it supports the growth of a wide variety of organisms. References * {{cite book , author = University of Minnesota, Medical School. , title = Biology of Microorganisms Laboratory Manual, year = 2006 Microbiological media ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptococcus Thermophilus
''Streptococcus thermophilus'' also known as ''Streptococcus salivarius ''subsp.'' thermophilus'' is a gram-positive bacterium, and a fermentative facultative anaerobe, of the '' viridans'' group. It tests negative for cytochrome, oxidase, and catalase, and positive for alpha-hemolytic activity. It is non-motile and does not form endospores. ''S. thermophilus'' is fimbriated. It is also classified as a lactic acid bacterium. ''S. thermophilus'' is found in fermented milk products and is generally used in the production of yogurt, alongside ''Lactobacillus delbrueckii'' subsp. ''bulgaricus''. The two species are synergistic, and ''S. thermophilus'' probably provides ''L. d. bulgaricus'' with folic acid and formic acid, which it uses for purine synthesis. ''S. thermophilus'' has an optimal growth temperature range of , while ''L. d. bulgaricus'' has an optimal range of . Classification At least 26 strains of ''S. thermophilus'' have been identified and had their genomes s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactobacillus Bulgaricus
''Lactobacillus delbrueckii'' subsp. ''bulgaricus'' (until 2014 known as ''Lactobacillus bulgaricus'') is one of over 200 published species in the ''Lactobacillus'' genome complex (LGC) and is the main bacterium used for the production of yogurt. It also plays a crucial role in the ripening of some cheeses, as well as in other processes involving naturally fermented products. It is defined as homofermentive lactic acid bacteria due to lactic acid being the single end product of its carbohydrate digestion. It is also considered a probiotic. It is a gram-positive rod that may appear long and filamentous. It is Motility, non-motile and does not form spores. It is also non-pathogenic. It is regarded as aciduric or Acidophile (organisms), acidophilic, since it requires a low pH (around 5.4–4.6) to grow effectively. In addition, it is Anaerobic organism, anaerobic. As it grows on raw dairy products, it creates and maintains the acidic environment that it needs to thrive via its produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
