In this lab students will simulate tests done in the field to determine the active ingredients in plants. This is the first step in a series of biotechnology steps to search for the reactive agents in newly collected plants. Students will be able to test known plants collected locally and also include known herbs for their healing properties. Plants demonstrating clear areas on Petri plates of bacteria would be further screen for the specific ingredients. The presence of clear areas indicates an active ingredient in the plant tested.
Active ingredients can include antiseptics, astringents, antibiotics and toxins.
One day for teacher preparation of the inoculum of Escherichia coli. One period for students to prepare their agar plates and plant material discs. The plates will need to be incubated for 48 hours, and then a class period to observe and record results. Using a notebook paper punch, punch small discs of filter paper and sterilize. Teacher may want to collect various known herbs to be tested.