A candle and a spirit lamp were lit and placed on each side of the setup to prevent microorganisms from spreading. The petri dish was divided into five segments and labeled as Sample 1, Sample 2, Sample 3, + Control (chloramphenicol), and – Control (distilled water). The vial containing the salt solutions was heated over the flame several times before being opened. This was done to eliminate any microorganisms that might contaminate the area. A swab was dipped into the vial, ensuring it was completely wet. The petri dish was then swabbed using the wet swab while holding it close to the flame. After this, the petri dish was closed, heated several times, and the swab was disposed off. Using forceps, three pieces of filter paper were taken and placed on the petri dish where Sample 1 (strawberry), Sample 2 (citrus lemon), and Sample 3 (green apple) were designated, with one piece on the – Control segment. The forceps were flamed before being reused. A drop of chloramphenicol was placed on the + Control segment, and one drop of deionized water was placed on the – Control filter paper. Next, a micropipette was used to suck in small amounts of the samples (strawberry, citrus lemon, and green apple) and these were placed on the corresponding filter papers according to the labeled samples, while holding the petri dish close to the flame. The petri dish was then closed and sealed with parafilm tape. The initial time was recorded, and the setup was left for 24 hours. After 24 hours, 48 hours and 72 hours, the zone of inhibition on each segment was noted, and as shown in the results table.
note: objective
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Statements that describe the steps or actions needed to achieve the aim.
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Must not be more than three objective
1 answer
To assess the antimicrobial effect of strawberry, citrus lemon, and green apple extracts on microbial growth by measuring the zone of inhibition in a controlled environment.
To evaluate the effectiveness of chloramphenicol as a positive control and distilled water as a negative control in inhibiting microbial growth.
To maintain aseptic techniques throughout the experiment to prevent contamination and ensure the reliability of results.
