Journal of Applied Microbiology, Vol.125, No.5, 1276-1285, 2018
Antimicrobial activity and phytochemical screening of Alpinia malaccensis (Ran-kiriya) against food-borne bacteria
Aims Investigation of antimicrobial activity and phytochemicals of Alpinia malaccensis (Ran-kiriya) against foodborne bacteria Staphyloccocus aureus, Listeria monocytogenes, Escherichia coli and Salmonella Typhimurium. Methods and ResultsConclusionsAntibacterial activity was tested on the above four foodborne bacteria using agar disc diffusion and broth dilution assay. Alpinia malaccensis rhizome extract chemical composition was determined using gas chromatography-mass spectrometry (GCMS). Active compound was identified using thin-layer chromatography (TLC) and confirmed by nuclear magnetic resonance spectroscopy (NMR). The A. malaccensis rhizome hexane crude extract showed significantly (P<005) higher diameter of inhibition (DIZ) 40052, 38096 and 36 +/- 145mm for S. aureusSA113, MSSASS25D and methicillin-resistant S. aureus compared with other tested bacteria. The minimum inhibition concentration and minimum bactericidal concentration were 0625 and 5mgml(-1) for S. aureus 113. TLC showed DIZ 39 +/- 012mm only for one fraction. The crude extract showed 8287% a major compound by GCMS which is the active fraction. This purified active fraction was confirmed as 1acetoxychavicol acetate (1ACA) by NMR. No significantly different inhibition was observed for crude extract and purified compound. Bioactive 1ACA of A. malaccensis showed strong antibacterial activity against S. aureus strains including MRSA strain. Significance and Impact of the StudyThis study is the first to identify 1ACA from A. malaccensis. The crude or purified compound could potentially be developed as antimicrobials.