Biology Practicals

Supplemented with sodium pyruvate and sodium chloride, tryptone soya soup can be used for selective enrichment of Staphylococcus Aureus. 

Learn what lysogeny broth (LB) is, its composition and recipe, how to prepare LB medium, its major formulations, uses for E. coli, and how LB broth differs from LB agar.

If the broth medium is supplemented with agar-agar it is referred to as agar medium like the nutrient Agar Medium (NAM) for the cultivation of bacteria potato dextrose (PDA) medium for the cultivation and storage of general fungi Czapek Dox agar (CDA) medium for fungi, starch-casein (SCA) media for the cultivation of actinomycetes, and so on.

Ashdown’s medium can be described as a selective culture medium that allows for the identification and characterisation of Burkholderia pseudomallei (the bacteria which causes the disease melioidosis). The Ashdown’s Medium was initially identified by LR Ashdown in 1979.

Bird Seed Agar Bird Seed Agar is an effective solid medium to isolate selectively and differentially of Cryptococcus Neoformans from clinical specimens. It is utilized for the specific isolation from Cryptococcus neoformans as well as C. Gattii. C. Neoformans typically grows as yeast (unicellular) and reproduces via budding. Cryptococcus Neoformans is an enclosed yeast, which makes the enzyme phenoloxidase an enzyme that is essential to melanin production. 

The process of growing an organism in the surface of a medium is known as culture. The food source that supports the development of the organism is known as a culture medium. The media for culture are designed so that the organism will receive all the nutrition requirements. However, the media for culture are made in laboratories by weighing and dispensing particular ingredients or by purchasing ready-made media on the market. The majority of the media include organic as well as inorganic nutrients. However, to cultivate a variety of microorganisms, special media are created. If the media is to be solidified required, agar-agar can be mixed with other ingredients. The culture media can be classified into three categories that include semi-synthetic, natural and synthetic media each of which is employed for microbiological studies.

Coliforms are all facultative and aerobic rod-shaped, gram-negative, non-spore-forming bacteria that produce lactose by fermentation with gas and acid production within 48 hours, at temperatures of 35 degrees Celsius. Methods to identify, enumerate and presumedly identify coliforms are utilized in the testing of dairy and food products. One method of performing the presumptive test to identify coliforms employs the Violet Red Bile Agar (VRBA). The Violet Red Bile Aggar (VRBA) is an selec-tive medium that can be used to detect and quantify lactose-fermenting coliform microorganisms.

Tryptic Soy Agar can be used to grow microorganisms. These media are non-selective and general-purpose. They provide enough nutrients to support a variety of microorganisms. This medium can also be used to grow, store, maintain, and transport pure microorganism cultures.

Baird Parker Agar was created by Baird Parker using the Tellurite–glycine formulation of Zebovitz et al. It allows for a good differentiation between coagulase positive strains.

Yeasts, unicellular eukaryotes, are a well-studied model organism in molecular genomics. They are chemoorganotrophs because they use organic compounds for energy. Yeast extract peptone, or YEPD), Growth Agar is used to maintain and propagate yeasts. YPD is a complete medium that allows for yeast growth.