Methodology:
The agar-well diffusion method was employed for determining the antibacterial activities using the following sequential processes:
1. Preparation of Agar containing Petri Dishes: Standard laboratory beaker was thoroughly cleaned and dried before any use. 100ml of tap water was poured into the beaker. The hot plate was switched onto number 1 and left for three minutes to prepare for heating. At the end of three minutes the beaker containing 100 ml of water was placed on hot plate. The water was allowed to heat to 100 °C which would effectively stop any bacterial growth in water. Thermometer was used to measure the temperature of water. 2.3g of Agar powder, measured by using a mass scale, was added to the water while it was being heated. The water was stirred with a rod to make it sure that the agar mixes well and forms a homogenous solution. Once the temperature of the solution rose up to 95°C, the hot plate was slowed down to 0.5 to allow the temperature to rise slowly to 100°C (Fig 3). Once the temperature reached 100°C, the beaker was moved away from the hot plate using a pair of tongs and placed onto the heatproof mat. The next step was to prepare 30 petri dishes which were provided by the lab in packed sterile form. Each petri dish was opened partially
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Filling the petri dishes with Agar solution without any consideration of bacteria exposure. Carefully open the petri dish cover however one must not expose the entire lid. It has to be improved as the exposure of the lid allows unwanted bacteria to grow in the petri dish thus creating an unfair experiment
The use of a pipette pump to insert solutions of extracts into holes. The use of a pipette pump may have been useful for larger holes, although in this case a smaller basic pipette should have been used. An unequal measurement of each solution creates an invalid experiment. There needs to be an equal amount of
We then took 1ml of the 1% solution from test tube 1 using the glucose pipette and added it to test tube 2, we then used the H2O pipette and added 9ml of H2O into test tube 2 creating 10ml of 0.1% solution
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
coli cells were grown at 37 degrees Celsius with calcium ions. These cells were then incubated in ice and placed into 4 polypropylene tubes. Each tube consisted of 25 microliters of E.coli cells. Two of the four were labeled with (+) while the other two were labeled (-). Positive was with samples that contained 100 pg/ microliter of pGLO, while negative was for the samples that did not. The 4 tubes were incubated in ice for 30 minutes, then heat shocked for 30 seconds at 42 degrees Celsius. The 4 tubes were then returned to the ice bath for 5 minutes. After the removal, .975 microliters of LB media was added to each tube at room temperature. The tubes were then shook at 225 RPM at 37 degrees Celsius for one hour. 300 microliters of cells were then extracted from the tubes and then placed in agar plates. The cells were spread across the plate and the incubated overnight at 37 degrees
Investigating the Effect of Concentration on the Rate of Diffusion Aim: To find out if concentration affects the rate of diffusion. Prediction: I predict that the higher the concentration of acid the faster the reaction will be. Hypothesis: Diffusion is the spreading out of a gas or liquid from an area of low concentration to another area where it has a lower concentration until the overall concentrations are balanced. The Hydrochloric acid (HCl) diffuses into the gelatine cube of which contains Sodium Hydroxide (NaOH), which is an alkali. When the Hydrochloric acid combines with the Sodium Hydroxide they form salt and water, which is neutral therefore turning the pink cube to clear.
a few of the germinating spores from the petri dish and put them under a
I identified the genus and species of an unknown bacterial culture, #16, and I applied the following knowledge of morphologic, cultural and metabolic characteristics of the unknown microorganism according to the laboratory manual as well as my class notes and power point print outs. I was given an incubated agar slant labeled #16 and a rack of different tests to either examine or perform myself; the tests are as follows: Gram Stain; Nutrient Gelatin Test; Carbohydrate Fermentation; Dextrose, Lactose and Sucrose; IMVIC tests; Citrate, Indole, Mythel-Red and Vogues Proskauer test; as well as a Urease and TSI Test. Materials and Methods/Results Upon receiving the Microorganism (M.O.) #16, I prepared a slide by cleaning and drying it. Then, using a bottle of water I placed a sterile drop of water on the slide and used an inoculating loop, flame sterilized, I took a small sample of the unknown growth in my agar slant and smeared it onto the slide in a dime sized circle and then heat fixed it for ten minutes.
- Each teaspoon may not have been equal. Measurements were made based on judgment and not exact measurements.
During the incubation, in an Erlenmeyer flask, 1X Tris Acetate EDTA (1 mL) and powder agarose (0.4 g) were dissolved in dH2O (49 mL). Then the solution was microwave for 2 minutes and allowed to cool to room temperature. Then SafeRed concentrate (2.5 µL) was added to the solution and it was poured into the gel box and allowed to solidify.
When evaluating the results from Investigations 1 and 2, it can be seen that the most influencing factor on the percentage of diffusion was the different surface area of the agar. As predicted in the second hypothesis, the 1cm cube had the highest diffusion percentage with 21.6% of the cube being affected in 8 minutes. This is a significant difference of 18.17% when compared to the 2cm cube’s diffusion percentage of 3.43 and a 20.38% difference from the 2.5cm cube’s result of 1.22%. Investigation 1’s results show that the most successful concentration of acid to diffuse through the phenolphthalein was the 1M with a percentage of 1.81. This is a 0.47% difference from the results of the 2M sulfuric acid. Graph 2 demonstrates that the diffusion percentage continued to incline when the concentration increased however starts to decrease past the 1.8 point. These results were unexpected and so a fifth trial was run in order
The next day, 100 µL of an overnight culture of Salmonella growth will be transfer onto the center of a Petri plate containing tryptic soy agar where taken out from refrigerator. Sprea...
Medicinal fumes emanating from the process of Agnihotra observed by researchers in the field of Microbiology clearly state that it is bacteriostatic in nature, which eradicates bacteria and micro-organisms, the root causes of illness and diseases. Hence, Agnihotra fumes may become the alternative way to combat the notorious microorganism present in air. Hence, the Agnihotra fumes can be used for disinfection of air also can be environmentally exploited for the physical, mental, intellectual and spiritual development(Pachori, Kulkarni, Sadar, & Mahajan,
There is also the potential of human error within this experiment for example finding the meniscus is important to get an accurate amount using the graduated pipettes and burettes. There is a possibility that at one point in the experiment a chemical was measured inaccurately affecting the results. To resolve this, the experiment should have been repeated three times.
Leboffe, M. J., & Pierce, B. E. (2010). Microbiology: Laboratory Theory and Application, Third Edition 3rd Edition (3rd Ed.). Morton Publishing
There were five test solutions used in this experiment, water being the control, which were mixed with a yeast solution to cause fermentation. A 1ml pipetman was used to measure 1 ml of each of the test solutions and placed them in separated test tubes. The 1 ml pipetman was then used to take 1ml of the yeast solution, and placed 1ml of yeast into the five test tubes all containing 1 ml of the test solutions. A 1ml graduated pipette was placed separately in each of the test tubes and extracted 1ml of the solutions into it. Once the mixture was in the pipette, someone from the group placed a piece of parafilm securely on the open end of the pipette and upon completion removed the top part of the graduated pipette.
Sewerage is the physical infrastructure, including pipes, pumps, screens, channels etc. used to convey sewage from its origin to the point of eventual treatment or disposal. Many bacteria can be found in wastewater. Relating the responsibility of bacteria on the phenomenon of biosorption and its presence on waste water, there are past studies venturing on the antimicrobial properties of essential oils and fruit parts. A study in 2013 by N.S. Al-Zoreky tested the antimicrobial activity against Listeria monocytogenes, S. aureus, Escherichia coli and Yersinia enterocolitica by various extracts from pomegranate fruit peels and was evaluated using both in vitro and in situ methods. According to Antimicrobial Resistance Learning Site (2013), an antimicrobial is any substance of natural, semisynthetic or synthetic origin that kills or inhibits the growth of microorganisms but causes little or no damage to the host. Antimicrobial destroys pathogenic microorganisms, in which one specific example is the Staphylococcus aureus. Staphylococcus aureus is a gram-positive, round-shaped bacterium that is a member of the Firmicutes, and is frequently found in the nose, respiratory tract, and on the skin. Skin infections are the most common form of S. aureus infection. This can manifest in