Disifectant lab - Assignment Example

Microbiology Lab 10 May Disinfection Lab Various disinfectants exert their effects in various ways dependingon the chemical compositions of their molecules (McDonnell and Russell 147). For example, Lysol acts by interfering with cell membranes and denaturation of bacterial proteins and enzymes. It is effective against Gram positive S. aureus (inhibition diameter of 30mm) and Gram negative bacteria (P. aureginosa and E. coli at inhibition diameters of 30 and 20 mm). Spic and span contains various chemicals including octyl decyl dimethyl ammonium chloride and dioctyl dimethyl ammonium chloride, which work by destroying the structure of the cell membrane.

It was highly effective in Gram positive S. aureus (inhibition diameter of 20mm) compared to the Gram negative bacteria (P. aureginosa and E. coli at inhibition diameters of 0 and 6 mm). Chlorox, which contains sodium hypochlorite works by unfolding and permanently aggregating vital bacterial proteins hence killing bacteria. Fabuloso is a cleaning agent without antimicrobial properties. However, it inhibited the growth of S. aureus and P. aureginosa (at inhibition diameter s of 25 mm and 36 mm respectively) by acting as a detergent and interfering with the cell membrane. 2. Each disinfectant worked as it did due to its chemical composition and interaction with the cell membranes of bacteria. 3. The disinfectants worked differently on different organisms because certain microbes such as E.

coli and P. aureginosa were Gram negative while S. aureus was Gram positive. All disinfectants were effective against S. aureus because they were able to traverse the thick peptidoglycan layer of its cell wall. In addition, the disinfectants contained different active ingredients, which had different chemical properties. 4. The disinfectant of choice for use in the kitchen, laboratory or on myself would be Clorox. I would choose Clorox because it showed the largest inhibition distance in the growth of the three microbes at inhibition diameters of 55 mm 54 mm and 46 mm for E. coli, P. aureginosa and S.

aureus respectively. Therefore, it would be an effective disinfectant because it would destroy an array of bacteria. In addition, it is relatively safe for human use since it contains chemicals that are used in the treatment of drinking water. Works CitedMcDonnell, Gerald and Denver A. Russell. “Antiseptics and Disinfectants: Activity, Action, and Resistance.” Clinical Microbiology Reviews. 12.1 (1999): 147–179.