Bleach Lab

Microchemlab.com states that a zone of inhibition is a qualitative method used clinically to measure antibiotic resistance and industrially to test the ability of solids and textiles to inhibit microbial growth. Researchers who develop antimicrobial textiles, surfaces, and liquids use this test as a quick and easy way to measure and compare levels of inhibitory activity (“Zone of Inhibition Test for Antimicrobial Activity”). The control of the experiment is distilled water. The independent variable is the different house cleaning products, and the dependant variable is the amount of growth or decline in the bacteria. Time, temperature, and amount of household household item are all constants in this experiment. Time needs to remain the same for all the products because time affects how well the bacteria grows. The temperature is required to stay the same as well because it can directly manipulate the rate of growth in the bacteria, and large amounts of the household item can offset the bacteria’s growth as

THE EFFECT OF INCREASING THE CONCENTRATION OF DETTOL ANTISEPTIC LIQUID ON THE GROWTH OF E.COLI

“Ajax Spray ‘n’ Wipe” specifically states that it kills E. coli. This is because of the lactic acid in the spray, which is used as a natural antibacterial agent.” ("Colgate-Palmolive | Product Ingredients"). Lactic acid kills unwanted bacteria especially in food which is where E. coli is often found and transmitted, of which meat is the most common cause. Vinegar was chosen as a substance because “it can be used as a bleach alternative” (“Disinfectants: A Guide to Killing Germs the Right Way”) and bleach kills E. coli. It is also used as an everyday cleaning product. The last substance chosen was salty water because it is thought that salt kills bacteria. Much of the world’s population has access to salt and if the experiment proves that salt kills E. coli it would be a helpful factor for further treatment of the

(Biology Dept.). 0.1 ml of E.coli K or 0.1ml of E.coli B was added to the 10 fold dilution. Using soft agar technique, the growth media mixture with E.coli was plated and incubated.

10% bleach solution is used to clean small biological spills like organisms being released with no big splashes or mess in the area.

6 petri dishes were labeled, 3 petri dishes P 105 B, P 106 B, P 107 B, and the other 3 petri dishes P 10 K, P 102 K, P 103 K and they were set aside. A series of dilutions for the 1x bacteriophage T4 rII

70µL of competent E.coli are added to both test tubes; pUC18 and Lux (Alberte et al., 2012). Both test tubes are then tapped and placed back into the ice bath for 15 minutes. While waiting, another test tube is obtained, filled with 35µL of competent cells and labeled NP for no plasmid. A water bath is preheated to 37 degrees Celsius and all three labeled test tubes are inserted into the bath for five minutes (Alberte et al., 2012). Using a sterile pipet 300µL of nutrient broth are inserted into both the control and Lux test tubes and 150µL are inserted to the no plasmid test tube to increase bacterial growth. All three test tubes are then incubated at 37 degrees for 45 minutes. Six agar plates are obtained and labeled to correspond each test tube, three of the plates contain ampicillin. A pipet is used to remove 130µl from each test tube containing a plasmid and insert it into the corresponding agar plate. For this, a cell spreader is first

E.coli outbreaks have steadily grown over the last few decades. An expansion in big farming has led to E. coli not only being found in meat, but vegetation as well, due to waste runoff. This has increased our need for adequate antibiotics that can fight bacteria, like E. coli. The best way to pinpoint which antibiotics work is by measuring their ability to create antimicrobial agents or zones of inhibition. When a paper disc that has been saturated in an antibiotic is inserted in a solution of E.coli and medium, the zone of inhibition will be noted as the clear ring that forms around the disk. The antibiotics efficacy is then determined by measuring each disk zone of inhibition, and comparing these measurements to the zone measurements of an untreated specimen. If an antibiotic is to be deemed sufficient for treating E. coli it should show a zone of inhibition that is at least double the size of the untreated specimen.

The ‘LB –DNA’ plate had a lawn of growth of the HB101 E. coli bacteria with no inhibition. The ‘LB/Amp –DNA’ plate had no growth seen. The ‘LB/Amp +DNA’ plate had small amounts of colonies that transformed but did not glow under UV light. Finally, the ‘LB/Amp/Ara +DNA’ plate had some colonies that transformed and glowed under UV lamp; some of the smaller, tiny colonies did not glow. Discussion Interpretation

coli bacteria affects bacterial growth and gene expression in several environmental conditions. To begin, two micro test tubes were labeled; one with +pGLO and one with -pGLO. 250 µl of transformation solution was added to each microtube, with use of a sterile pipette. Afterwards, the pipette was placed in a bleach solution and the microtubes were placed into the foam rack and onto crushed ice. Next, a colony of bacteria was removed from the starter plate with a sterile loop and thoroughly mixed within the +pGLO microtube. This step was repeated with a second sterile loop and the -pGLO microtube. After their use, all loops were placed in the bleach solution for decontamination and the microtubes were returned to the foam rack and ice.

Figure xxx: The total plate count of the Escherichia coli from day one to seven.

This experiment is about bacterial growth. We will demonstrate a bacterial growth curve using a closed system. Bacterial growth usually takes up to 12-24 hours to get an accurate result so we will be monitoring this growth between two classes. We also used different methods to determine bacterial growth as well as a few different calculations. One way of receiving data is by using a spectrophotometer where we will record the absorption at a given time to create the bacterial growth curve. We also used the plate count method after performing a serial dilution to calculate the actual cell density at different times given. By using this method we can count the population number of the same given and see the maximum cell density

There was no difference between the control plates which proves that the lid on the plate serves as significant protection, potentially shielding the bacteria to the mutagenic effects the UV light. All three plates were incubated at 25 degree Celsius. The first Control plate showed lots of red and furry growth and the original pattern of swiping was observed in all the quadrants. The second control plate was also observed to have furry and pigmented red growth in all the quadrants, despite being exposed to UV light due to the plate lid during exposure. The experiment plate showed the most interesting results, in the 10 second UV exposure quadrant the bacteria had red pigmented growth but it is speckled, pinpointed and the original swipes were not observed. Moreover the growth seemed not as furry and robust as the control plates. The quadrant exposed to 20 sec of UV light showed significantly less growth than the 10 sec quadrant and the colonies are pinpointed with several beige colonies in between the red speckles. Original swipe pattern of the bacteria was not observed in this colony. In the quadrant exposed to 30 seconds of UV light, the differences are even more significant as the colonies are few and far in between and only several pinpoint red colonies found with a few beige colonies and some colonies with red centers surrounded by beige. The effects of UV light are very drastic in the 40 second quadrant as the growth is severely diminished with only a

Being able to control bacterial growth is something that is important in our everyday lives. As shown in the previous labs, bacteria can grow and create colonies extremely quickly especially in the right environments. By acknowledging this, it is then important to get an understanding of how bacterial growth can be controlled by humans. To control microorganisms it means to inhibit their growth (static) and or kill them (cidal) (Kenneth Todar, 2015); therefore since focusing on bacteria the terms bactericidal and bacteriostatic are both extremely important for this lab. One broad method we will use to control bacterial growth is heat. The amount of heat needed to control bacterial growth is different for different species of bacteria (Kenneth Todar, 2015). Bacteria can also respond differently depending if moist heating method such as an autoclave with steam is used, or a dry heating method such as inoculating a loop over a fire is used (Kenneth Todar, 2015). UV works by damaging the cells DNA, without proper DNA, the cells will die and the object

Joan Macey, the Rohm and Haas market manager for Metalworking Fluid Biocides, was reviewing the marketing approach for the recently introduced Kathon MWX maintenance biocide. Rohm and Haas is one of several manufacturers that develop liquid biocide chemicals for eliminating microorganisms in metalworking fluids. The company currently manufactures the Kathon 886 MW concentrate biocide, the leading biocide in the concentrate biocide market. Kathon 886 MW is a very powerful concentrate used for large-capacity reservoir systems (above 1,000 gallons) and is too powerful for small fluid reservoirs. As a result, the company developed the Kathon MWX maintenance biocide for use in