Gram Stain Lab Report

As many as 1 mL hydrogel preparations added in 1 mL of growth medium with stratified so that dilution dilution series made were 50%, 25%, 12.5%, 6.25%, 3.12%, 1.56%, 0.78%, 0.39%, 0.02%, and 0.01% by volume end of the tube was 1 mL. Then as much as 1 mL of bacterial culture equal Mc. Farland 0.5 added into the test tubes so that the final volume of the tubes were 2 mL. All test tubes were incubated at 37 °C for 18 h. Turbidity test observed in the media and determined MIC value preparations. Tube with negative results or does not indicate the presence of growth, then conducted subculture with solid growth media each bacteria as test assertion MIC value chloramphenicol preparations hydrogel. As many as 20 mL of growth medium was prepared and then given solids have zones for the variation of concentration with the method MIC macrodillution preparations showed the absence of growth.

Then, the test media is then incubated at 37 ° C, for 18-24 hours. Rinsing reusable instruments The samples were rinsed with 40 ml of pyrogen-free water using a glass beaker that is free from pyrogens. Endotoxin testing using STV

Discussion Bacteria from the provided master stock plate were used for the gram stain test. Bacteria were then streak and grown from the master stock plate onto a working plate. After an incubation time of 24 hours at 37°C, the working plate bacteria were then used to perform the catalase and red blood cell hemolysis tests. After conducting the three tests, it was concluded that unknown #5 was Streptococcus agalactiae. Gram Stain Test

The solidified gel was then removed from the chamber and placed under UV light. A digital image was then taken, allowing for analysis to be carried

The supernatant was then used as enzyme extract. • Hydrogen peroxide (H2O2, 2mM) in phosphate buffer (3.0ml) was taken in an experimental cuvette, followed by the rapid addition of 40μl of enzyme extract and mixed thoroughly. • The time required for a decrease in absorbance by 0.05 units was recorded at 240nm in a spectrophotometer (Genesys 10-S, USA). • The enzyme solution containing H2O2-free phosphate buffer

They were mounted in L blocks with molten paraffin and solidified. The solidified blocks were trimmed to small size and sectioned using microtome (Spencer U.S.A) 3 to 5-micron thickness. 5.2.3 Toluidine blue Staining: Toluidine blue is a metachromatic stain that stains nucleus which appears blue in color. The isolated rat's brain was fixed and processed as per the tissue processing procedure, and then brain tissue slices were prepared for toluidine blue staining.

The above solution converts of colorless to yellow suspension solution which produced TiO2 nanopowder by drying process at 85°C in anstove for 15 hours. Finally, TiO2 nanopowder obtained were treated in furnace at different temperatures (400°C-800°C) for 2 hours. The initial heating rate was maintained at 5 °C/min. 2.3. Characterization 2.3.1 UV- Visible diffuse reflectance spectroscopy (DRS)

In Part A of the experiment which is sterilisation technique, three types of technique is used. The first technique is dry-heat sterilisation. Dry heat sterilisation takes a long time and is done at a high temperature of about 160°C for 60 minutes. In dry-heat sterilisation, there is two parts which are heating and flaming. Heating is when the inoculating loop and the needle are burned in the direct flame until it turns red in colour while flaming is just passing the forceps and mouth of the culture tubes through the flame to prevent bacteria from entering.

Q1A: What is the mechanism of action of colistin? Colistin is an antibiotic that works best against Gram-negative bacteria. It works by binding to LPSs (lipopolysaccrides) and phospholipids in the outer cell membrane of the bacteria. This, in turn, disrupts the outer cell membrane by displacing cations and leaking the intracellular contents, combining it with outer cellular contents, causing the bacteria to be unable to differentiate the bacteria’s intra and outer cellular contents from one another.

Apparatus- Chromatography column: C18 (10 microns particle size), with Guard column Flow rate: 1.2ml/min Pressure: 30-40kgf Wavelength: 326nm Mobile phase: methanol : water (95:5 v/v) Internal standard: retinyl acetate Injection volume: 20µl Procedure for Retinol extraction from serum samples- 1) 100 µl of serum sample and 100 µl of Retinyl acetate were added into 12 X 100mm glass test tubes. Vortex-mixed for 30 seconds. Then, kept them at 4 C for 5 mins. 2) 1mL of hexane was added and vortex-mixed intermittently for 60 sec.

Each plate serves as a first step to identify the unknowns. The TSA (tryptic soy agar) can be used to do a gram stain, which differentiates gram-negatives from gram-positives, based on the structural make up of the cell wall (Carson, 2015). The blood agar plate is used to test for hemolytic activity, which is useful for distinguishing gram-positives. A MacConkey plate is selective by inhibiting the growth of gram-positives and differential due to the fermentation of lactose by certain gram-negative species. In the