The Efficiency of Toilet Seat Cleanser on Bacterial Growth - Lab Report Example

The efficiency of toilet seat cleanser on bacterial growth The research on efficacy of toilet seat cleanser was conducted by Wang Adrian, NOEL-CHAN Adele, WuSiu Man Cathy and NGHiu Tung Cheryl. The research questions being tackled were such as; does application of cleanser kill active bacteria? How efficient are cleansers in dealing with other pathogens? The sample collection and lab analysis was done under asceptic conditions to ensure no external factors affected the result. The experiment yielded positive findings, as most bacteria (excluding spores) and fungi were killed by the sanitizer. This led to the conclusion that sanitizers are effective at controlling bacterial growth on toilet seats. This has the implication that seat sanitizers need be included as part of proper hygiene to prevent infections and transmission of pathogens. Hypothesis ‘An effective toilet seat cleanser should eliminate most of the bacterial species inoculated unto toilet seats by users’ Materials Agar plates Sterile swab Liquid broth Sanitizer Prepared agar Reagents/stains; Chrystal violet, Safranin, alcohol, gram’s iodine Slides Bunsen burner Inoculation loops Distilled water Procedure 1) Obtaining and culture of bacteria The asceptic method was used throughout the experiment. This refers to measures that limit contamination by organisms other than the intended. This included the collection, inoculation, staining and microscopy. The collected samples were from 2 male and 2 female toilet seats. Sterile swabs were moistened with distilled water and used to swab the seats. The swabs were then dipped in the pre prepared broth. This was then repeated after application of the cleanser. All samples collected into the broths were then labeled and diluted as follows 20 microliters of all dilution of samples are subjected to the agar plate for plate count. The samples A1, C1, B1 and D1 are used to seed culture media with agar plate by using the streak plate method. All the plates were then cultured for 2 days. 2) Plate count and gram stain a) Plate count A1 – 8 A2 – 1 A3 – 1 A4 – 0 A5 – 3 B1.1 – 25 B2.1 – 0 B1.2 – 3 B2.1 – 0 B1.3 – 0 B2.3 – 0 B1.4 – 0 B2.4 – 0 B1.5 – 1 B2.5 – 0 C1.1 – 13 C2.1 – 1 C1.2 – 1 C2.2 – 0 C1.3 – 1 C2.3 – 0 C1.4 – 0 C2.4 – 0 C1.5 – 1 C2.5 – 1 D1.1 – 2 D2.1 – 3 D1.2 – 0 D2.2 – 1 D1.3 – 1 D2.3 – 0 D1.4 – 1 D2.4 – 0 D1.5 – 0 D2.5 – 0 The same procedure was repeated for the swabs taken on the sanitized seats. b) Gram stain and morphology To study the morphology of the bacteria obtained, the agar plates were first studied. This gave an overview of colony morphology. Then, bacterial samples from each plate were obtained, stained and viewed under a microscope at a magnification of X400. Gram stain procedure Obtain the bacteria from the agar with inoculation loop Streak and spread on a clean microscope slide Pass the loop through the Bunsen flame until red hot to sterilize (cool before repeating inoculation) Repeat for all other plates and carefully name respective slides Flood slide with crystal violet solution for a 60 seconds and proceed to wash off briefly with tap water Flood slide with Gram’s iodine solution for another minute and then wash off with tap water Flood Slide with alcohol and flood slide with Safranin solution for about a minute and then wash off with tap water Then place the slide under the microscope objective lens to identify and resolve the character of the bacteria. They were as follows; 2 Bacteria Samples from Agar plate A 3 Bacteria Samples from Agar plate B 2 Bacteria Samples from Agar plate C 2 Bacteria Samples from Agar plate D Results i) The morphology results of the culture were as follows; Plates A (1st) Bacteria – Circle, Flat, Milky White, Small colonies A (2nd) Bacteria – Yellow, Circular, Small colonies B (1st) Bacteria – Big Circular, White colonies B (2nd) Bacteria – Small White, Circular colonies B (3rd) Bacteria – Small Circular, yellow colonies C (1st) Bacteria – Small, has white border and yellow center C (2nd) Bacteria – Small Circular, White D (1st) Bacteria – Small circle dot, with white border D (2nd) Bacteria – Light white, small colonies Culture pictures Toilet seat A Toilet seat B B(C) Toilet seat C Toilet seat D ii) Microscopic morphology results A (1st) Bacteria – Coccus, gram positive A (2nd) Bacteria – Normal Flora (Seems like) candida, with single Coccus B (1st) Bacteria – Normal Flora (Seems Like), with coccus, B (2nd) Bacteria – Coccus- staphylococci B (3rd) Bacteria – Coccus- staphylococci C (1st) Bacteria – shape long rod- lactobacilli or hemophilus influenzae C (2nd) Bacteria –e coli D (1st) Bacteria – Coccus with normal flora- streptococcus aureus, s. epidermidis or s mutans D (2nd) Bacteria – -enterococcus faecalis The culture of the samples from the sanitized seats gave a negative result. This implies that no bacterial colonies grew due to lack of the colony forming units. Discussion It was expected that most of the cultured bacteria were obtained from seat contact with human bodies, excreta and clothing. These bacteria include the normal microbial flora of the skin, gut and bacteria found within the air and soil. These may have found their way unto clothing, and thus the seat as well. It was also possible that fungi may have been included in the cultures, as fungi are also normal flora that coexists with bacteria. The bacteria include; staphylococcus epidermidis, staphylococcus aureus, streptococcus mitis, proteus species, enterococcus faecalis, streptococcus pyogenes, the enterobacteriaceae, lactobacilli, actinomycetes, bacterioides fragilis, bifidobacterium bifidum (davies, 1996) The fungi include; candida albicans (davies, 1996) In essence, application of cleanser should kill all the microorganisms and leave only spores. This would be confirmed by microscopy and culture of the samples taken after application of the sanitizer. Most sanitizers are alcohol based, and may also be alcohol free. They may contain ethanol, n-propanol, providone iodine, benzalkonium chloride. The most effective contain a persistent antiseptic agent, or more than 60% alcohol content. These are effective against most bacteria, fungi and protozoa. Those with higher concentrations may also provide virucidal properties. As mentioned earlier, some bacteria produce spores. An example is the clostridium deficile whose spores are resistant to soap as well. Conclusion The sanitizer seemed to work efficiently killing most of the bacteria present on the seats. This is important for the prevention of transmission of infection from one individual to another even without the necessary hygiene procedures of hand washing. This is especially important in hospital settings where nosocomial infections are common. Furthermore, it is essential to note that even though the risk is minimal, spread of highly virulent pathogens such as viruses and some protozoa is also stemmed. References Davis CP. (1996). Normal flora. Retrieved from http://www.ncbi.nlm.nih.gov/books/NBK7617/ Read More