Year 12 students experimented to see whether adding ingredients like garlic or curry powder could boost the anti-bacterial properties of toothpaste. They crushed up a variety of herbs and spices and the resulting pastes were smeared on sterile discs of paper and placed on bacteria-filled agar plates. After 24 hours the students will examine the plates under a microscope to see how effectively each compound has cleared the bacteria.
Teacher Mrs Annable said: ‘The students are investigating if there is a more effective anti-bacterial that we could use in toothpaste rather than mint. At the moment they are performing a core practical, something that potentially they may be examined on in their June exams. We have got a variety of herbs and spices, including sage, cloves, curry powder, mustard powder as well as essential oils like tea tree, just so we can see if there is any anti-bacterial action; a zone of clearing. The bigger the zone of clearing surrounding the little disc is then the better the anti-microbial action is. The initial stage is to see how well each compound works individually. Once the results are in the next stage would be to add two together and see if the results were better or worse.’
The students worked in small groups. Lena Sytchenko said: ‘I am grinding up some mint with ethanol to make a paste and we will also test the garlic as well to see which is the better anti-bacterial; we think it might be the garlic.’