Stand 8

The purpose of my project is to identify potent antimicrobial compounds in herbal plant extracts using high performance liquid chromatography (HPLC) to address the issue of antibiotic resistance.

Methicillin-Resistant Staphylococcus aureus (gram-positive bacteria), Staphylococcus epidermidis andCorynebacterium striatum were the antibiotic-resistant bacteria tested. The agar disk diffusion method was used to investigate herbal and vegetable extracts as natural, sustainable and economical antimicrobials against skin infections. They are not harmful or toxic chemicals, and some are locally abundant. Crude extracts of these herbal plants were prepared and filtered with ethanol to create concentrations of 25%, 50%, 75% and 100%.

For the investigation of S. aureus, S. epidermidis and C. striatum, agar disk diffusion methods were used by the addition of filter discs saturated in herbal extracts . Bacteria were grown in a CO₂incubator at 35 °C and then observed for a zone of inhibition.

My main results were that nelli/gooseberry extracts showed the strongest inhibition on the growth of S. aureus due to the zone of inhibitions shown.

I then used the high performance liquid chromatography (HPLC) method to analyse the active components in gooseberry extract that are effective against antibiotic-resistant bacteria. I compared the nelli from my homeland Sri Lanka and commercially bought in an Asian supermarket in Ireland to complete further comparisons and research.

After identifying compounds such as ascorbic acid and gallic acid, I tested them against S. aureus using the disk diffusion method again.