- Tryptic soy agar (TSA) is general-purpose growth medium that is made through enzymatic digestion of casein and soybean. It supports growth of a wide range of microorganisms including the nonfastidious and semifastidious bacteria. However, fastidious bacteria that have particular nutrient requirements would not grow in TSA. An example of such a microbe is Neisseria gonorrhea, which needs several amino acids, blood, and vitamins to culture. Other examples include Helicobacter spp. And Campylobacter spp., which require high levels of carbon dioxide. Such microbes can only thrive in their own ecological niche with particular temperature and nutrient needs. TSA lacks the primary nutrients for these microorganisms and therefore fail to support their growth (Robinson, 2014). Regardless, the digests of soybean and casein in the medium makes it nutritious enough for most the nonfastidious microorganisms.
Sabouraud agar is selective for dematophytes and other fungi as well as filamentous bacteria such as Nocardia. Therefore, any other microorganism would not grow in this medium. It is produced by enzymatic digestion of casein and animal tissue to provide a nitrogen source for the growth of yeasts and fungi. The carbon and energy source is in form of dextrose. Besides, it contain antibiotics that impede the growth of a wide range of gram-positive and gram-negative bacteria. It has an acidic pH that that promotes the growth of filamentous fungi while inhibiting bacteria. A high concentration of dextrose and acidic pH promotes the growth of fungi and inhibit bacterial growth (Hare, 2013). The medium would not support growth of conidiospores and basidiospores because it does not support the conidiation of filamentous fungi. Besides, it would not be appropriate for isolation of fastidious fungi, especially most of the dimorphic fungi because it is not sufficiently enriched.
- Tryptic soy agar is a general growth medium that supports the isolation and cultivation of a wide range of microorganisms. It is non-selective and general-purpose. It is used in the growth, storage, and maintenance as well as transportation of pure culture of various microorganisms. Some of these microorganisms include Aspergillus brasiliensis, Candida albicans, Staphylococcus aureus, Bacillus subtilis, Pseudomonas, aeruginosa, Escherichia coli, and Salmonella Typhimurium (Robinson, 2014). Besides, of the microorganisms with that are non-selective in terms of nutrients and other growth conditions can grow on tryptic soy agar.
Sabouraud agar supports the growth of fungi, especially the filamentous type. Dematophytes can be isolated using this medium. Their incubation require long periods. Example of these microorganisms include Rhodotorula species, which appears as pinkish-orangish creamy colonies, Aspergillus fumigatus, which are blue – green, powdery, Trichosporon mucoides, which are whitish and wrinkled, and Aspergillus nidulans, which are greenish-blue with whitish edges. The medium is being used to perform mycological evaluation of cosmetics, food, and in the diagnosis of fungal and yeast infections (Hare, 2013). Besides, the medium can promote the growth of filamentous fungi such as Nocardia.
If MacConkey agar had been use instead of TSA and SAB, the organisms that would have grown would be gram-negative bacteria. It is a selective as well as a differential medium that facilitate the distinction between lactose-fermenting gram-negative and non-lactose fermenting gram negative bacteria. The microorganisms that would primarily grow in the medium include Pseudomonas spp. and enterobacteriaceae (Jung and Hoilat, 2020). If Mannitol Salt agar had been used, the type of microorganisms that would grow include Staphylococcus aureus and Staphylococcus epidermidis. It is selective for gram-positive bacteria (Kateete et al., 2010). Besides, it is differential for mannitol fermenters.
- Maquat 128-PD is one of the disinfectant used against SARS-CoV-2 and is made by Mason Chemical Company. Its EPA number is 10324-105. The active ingredient is quaternary ammonium. The contact time that is recommended to deactivate SARS-CoV-2 is 10 minutes. It is dilutable and is recommended for use in health facilities and at home. While the efficacy of the product on SARS-CoV-2 that causes COVID-19 has not been tested, it is expected to be effective because it has been tested and proven to be effective on another human coronavirus that is genetically and morphologically similar to SARS-CoV-2 (United States Environmental Protection Agency, n.d.). Besides, the product is effective on deactivating Methicillin-resistant Staphylococcus aureus (MRSA), thereby reducing the spread of the infections among human beings.
Maquat 128-PD is recommended for use in all facilities including hospitals, institutions, and residents. It is efficient in disinfecting hard surfaces as well as organic surfaces such as hands. Therefore, it can be able as a sanitizer to curb the spread of the pandemic. Mason Chemical Company has produced a number of disinfectants that have been approved by both EPA and OSHA in terms on their safety and non-toxicity. It is in the frontline in providing solutions towards the containment of the pandemic. The active ingredient of Maquat 128-PD is a membrane-active agent that interact with the lipids of the virus, thereby destroying it. The product has been shown to destroy the virus as long as the appropriate contact time of ten minutes is allowed to elapse before a surface can be used or the disinfectant is wiped off from hands.
