Antimicrobial activity of Citrus hystrix and Citrus aurantifolia essential oils / Siti Muhayyah Omar

The composition of the essential oils extracted by solvent extraction from leaves and peels of Citrus hystrix (limau purut), was analyzed by gas chromatography-mass spectrometry (GC-MS). The major compounds in leaves extract of Citrus hystrix were citronellal (31.16%), (R)-citronellol (7.67%), and β-linalool (1.88%) meanwhile the major compounds in peels extract were limonene (12.43%), β-citronellal (4.87%), β- citronellol (4.23%) and linalool (1.49 %). The percentage yield of essential oil from leaves and peels of Citrus hystrix was 7.03% and 8.81% (w/v), respectively. Extracts of Citrus hystrix and Citrus aurantifolia were investigated for its antimicrobial activity against microorganisms: Escherichia coli (25922), Staphylococcus aureus (29213), Saccharomyces cerevisiae (itm: 3005) and Candida albicans (10231) using disc diffusion method. Moderate antimicrobial activity has been observed by using the hexane extract of leaf against Staphylococcus aureus, and Escherichia coli with zone inhibition of 25 mm and 20 mm, respectively. Antimicrobial inhibition was absent against Candida albicans and Saccharomyces cerevisiae species. Mild antimicrobial activity against Staphyloccocus aureus and Escherichia coli has been observed in Citrus aurantifolia extract with zone inhibition of 8 mm and 9 mm, respectively. Antimicrobial activity was absent against Candida albicans and Saccharomyces cerevisiae species.