Editorial Team

Editorial Team | Academic Writer

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Cetrimide Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 16 min readby Editorial Team

Cetrimide, a quaternary salt of ammonium, acts as a detergent that lowers the surface tension at the point-of-contact. It also has precipitant, complexing, and denaturing effects upon bacterial membrane proteins. It has inhibitory properties on many microorganisms, including Pseudomonas species that are not Pseudomonas. Lowburry was the first to develop cetrimide agar. It is a modified version of Tech Agar (developed in King et al. For the selective inhibition other than Pseudomonas, aeruginosa, 0.1% cetrimide (cetyltrimethyl ammonium bromide), was added. Cetrimide agar can be used to presumptive identify and selectively isolate Pseudomonas.aeruginosa species from both clinical and nonclinical specimens.

Middlebrook Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 15 min readby Editorial Team

Over the years, many media have been developed for mycobacteria cultivation. Early ones included egg-based formulations such as Lowenstein-Jensen Medium or Petragnani Medium. Later, Dubos, Middlebrook and Middlebrook created a variety of formulations that contained oleic and albumin as key components. These ingredients protect Mycobacterium against toxic agents and allow for the growth and development of tubercle bacteriailli. Cohn and Middlebrook improved the formulations of oleic acids-albumin agar to achieve a faster and more luxurious growth of Mycobacterium strains.

Endo Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 14 min readby Editorial Team

Endo created Endo Agar to distinguish gram-negative bacteria based on lactose fermentation and inhibit gram-positive bacteria. The latter were not inhibited by bile salts, as was traditional. Endo was able to inhibit gram-positive bacteria using sodium sulfite, basic fuchsin.

Bismuth Sulphite Agar (BSA) – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 14 min readby Editorial Team

Salmonellae are the most complex taxonomically diverse group of bacteria in Enterobacteriaceae. Salmonella infections in humans are usually caused by the consumption of food, milk, and water contaminated with animal or human excreta. S. Typhi is only found in humans.

Egg Yolk Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 15 min readby Editorial Team

Egg Yolk Agar modified is based upon the original Egg Yolk Agar formula developed by McClung & Toabe to isolate and differentiate organisms based in Lecithinase, lipase production, and proteolytic activities.

Brilliant Green Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 16 min readby Editorial Team

As a primary plating medium, Brilliant Green Agar medium should be used to isolate Salmonella species. Kristensen and colleagues first described it as a selective isolation medium to Salmonella species. Kristensen et al. first described it as a selective isolation medium for Salmonella species. Kauffmann modified the formula to make it a highly selective plating media for the isolation and identification from salmonellae in feces, other pathological material, food and dairy products. Brilliant Green Agar should always be used in conjunction with other selective plating media like Deoxycholate Citrate Agar and Hektoen Enteric Agar. Salmonella Typhi is treated with Bismuth Sulphite.

Hektoen Enteric Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 21 min readby Editorial Team

Hektoen Enteric Agar, a selective and differential medium, is used to distinguish Salmonella and Shigella species from other Enterobacteriaceae. Sylvia King, William I. Metzger introduced the medium in 1968. They developed HE Agar medium during their time at the Hektoen Institute, Chicago, in order to improve the recovery of Salmonella and Shigella from clinical specimens.

Yersinia Selective Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 15 min readby Editorial Team

Schiemann first described Yersinia selective agar as an alternative to MacConkey agar and other media commonly used for isolating Yersinia Enterocolitica, a causative organism of gastroenteritis. Yersinia Enterocolitica, a major food- or waterborne enteric pathogen, has been reported to cause epizootic outbreaks in animals such as diarrhea, lymphadenopathy and pneumonia. Yersinia Selective Agar, a selective and differentiated medium that supports the growth of Y. Enterocolitica and other Yersinia spp.

CLED Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 13 min readby Editorial Team

Cystine-Lactose-Electrolyte-Deficient (CLED) medium, first described by Sandys and later modified by Mackey and Sandys, is generally used for diagnostic routine urinary bacteriology as a non-selective medium capable of supporting the growth of most urinary pathogens. CLED Agar, a differential medium for the isolation and counting of bacteria from urine, is used. It supports the growth all potential urinary pathogens. The medium also provides distinct colony morphology. It is suitable for the growth of all urinary pathogens, contaminants, and provides good colonial differentiation. However, it does not allow for the spread of Proteus species because of its low electrolytes.

TCBS Agar – Composition, Principle, Preparation, Results, Uses

• Published on May 16, 2024 • 11 min readby Editorial Team

Thiosulfate-citrate-bile salts-sucrose (TCBS) Agar, is a type of selective agar that is used in microbiology laboratories to isolate Vibrio species. TCBS Agar can be used to cultivate Vibrio cholerae from clinical specimens or other materials. Kobayashi et. al. developed TCBS Agar, which modified the Nakanishi selective medium. This medium was originally intended to isolate V. cholerae from V. parahaemolyticus. However, Vibrios can grow healthy colonies with many different colonial morphologies.