Background: All plants can be infected by viruses and bacteria, but many of them have a defense mechanism. Isolating this antimicrobial molecule could give a possible medicine. Finding an active ingredient that has antimicrobial activity is a difficult process. Samples must be collected and tested for their ability to kill microbes and prove that it doesn’t cause bad effects in humans. The process for testing the plants are adding an extract-soaked filter paper disks to bacteria cultures on Petri plates. Then they see if there are clear halos in it. That means it inhibited the bacteria’s growth or killed it.
Purpose/Objective: What plant materials, found locally, contain active ingredients that will inhibit the growth of bacteria?
Materials:
Procedure:
Results:
Purpose/Objective: What plant materials, found locally, contain active ingredients that will inhibit the growth of bacteria?
Materials:
- Balance, weigh boat, lab scoops
- LB broth base
- Media bottles, 250 mL
- Sterilizer/autoclave
- Water bath
- Sterile LB agar
- Laminar flow hood and disinfectant
- Glasses
- Bunsen burner and gas lighter
- Inoculating hoop
- Petri dishes
- E. coli
- Plant specimen (white rose leaves)
- Mortar and pestle
- Pipet
- Plastic funnels
- Filter paper disks
- Beakers
- Syringe
- Reaction tubes and rack
- Methanol
- Dry block heater
- Forceps
- Ampicillin
- Glass spreader
- Incubator
Procedure:
- 2g of plant material were measured
- Using a mortar and pestle, 2 g of plant tissue were ground up with 10 ml of deionized water
- It sat for 3 minutes
- The sample was filtered through an 11 cm filter paper funnel
- The extract was filter-sterilized using a syringe filter
- 1 ml of extract was collected into a 1.7 ml microtube. The tube was labelled.
- Previous steps were repeated using methanol instead of water
- Flame-sterilized forceps were used to transfer filter squares into the water and Ampicilin control
- Each plate was labelled into 4 sections
- The E. Coli was dispensed into the plates
- The filter disks were placed in the plate
Results:
24 Hours:
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bacterial lawn not solid, no clearings around positive control, negative control or experimental disks, no signs of contamination
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bacterial lawn semi-solid, no clearings around positive control, negative control or experimental disks, no signs of contamination
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48 Hours:
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bacterial lawn semi-solid, small clearing around positive control, no clearings around negative control or experimental disks, no signs of contamination
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bacterial lawn solid, clearings around positive control, no clearings around negative control or experimental disks, no signs of contamination
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