Jia Xin Tang

• BSc (Hons) Biomedical Sciences (NUmed 2+ 1)
• Assessment of Antimicrobial Property of Hedyotis diffusa (White flower snake tongue grass) Extracts

As conventional antibiotics increasingly conferred bacterial antibiotic resistance, plant-derived antimicrobials have become potential alternatives. The project aims to investigate antimicrobial activity of H. diffusa, commonly used in Traditional Chinese Medicine for inflammation-related conditions, against opportunistic pathogen. Secondary metabolites of H. diffusa were extracted using three different solvents, namely ethanol, methanol and water through maceration. Kirby-Bauer disc diffusion assay and broth microdilution assay were used to test susceptibility of Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli K12 towards H. diffusa extracts. Disc diffusion assays of all three extracts returned negative antimicrobial activity. On the other hand, broth microdilution assay suggested possible antimicrobial activity of H. diffusa extract against S. aureus and S. epidermidis but not E. coli K12. Both ethanol and methanol extracts recorded a minimum inhibitory concentration (MIC) of 15 mg/ml against S. aureus and S. epidermidis whereas aqueous extracts has an MIC of 60 mg/ml against S. epidermidis.

Funded by: NUMed Malaysia

Project Supervisor: Dr James Woon