Objective: To investigate chemical constituents and new antimicrobial agents among essential oils from the rhizomes of Curcuma aeruginosa(C. aeruginosa) Roxb., Curcuma glans K. Larsen & J. Mood and Curcuma cf. xan...Objective: To investigate chemical constituents and new antimicrobial agents among essential oils from the rhizomes of Curcuma aeruginosa(C. aeruginosa) Roxb., Curcuma glans K. Larsen & J. Mood and Curcuma cf. xanthorrhiza Roxb.Methods: The essential oils were obtained by hydro-distillation and analyzed by gas chromatography/mass spectroscopy. Agar-well diffusion assay was used to study the antimicrobial activity and also broth-micro dilution techniques were examined for minimum inhibitory concentration(MIC) against four bacterial strains and yeast.Results: The gas chromatography/mass spectroscopy analysis showed monoterpenes predominantly(88.53%) in the rhizome oil of Curcuma cf. xanthorrhiza. Sesquiterpenes(50.10%) was the most abundant component in the essential oil of C. glans, while monoterpenes(45.55%) and sesquiterpenes(45.81%) were found in C. aeruginosa with a significant amount. The major components of C. aeruginosa were characterized as camphor(29.39%) and germacrone(21.21%). Germacrone(15.76%), b-pinene(9.97%)and camphor(9.96%) were found as major compounds in the rhizome oils of C. glans while a-terpinolene(24.86%) and p-cymen-7-ol(12.17%) were found as major compositions in Curcuma cf. xanthorrhiza. The essential oils were tested against four bacterial strains and yeast. As a result, the rhizome oil of C. aeruginosa exhibited potent activity against Staphylococcus aureus [inhibition zone(21.94 ± 0.24) mm, MIC 125 μg/mL],Bacillus cereus [inhibition zone(20.83 ± 0.36) mm, MIC 125 μg/mL], and Candida albicans [inhibition zone(11.60 ± 0.30) mm, MIC 250 μg/mL].Conclusions: The essential oils from three Curcuma species possessed greater activity against the gram-positive bacteria(Staphylococcus aureus and Bacillus cereus) than gram-negative bacteria(Escherichia coli and Pseudomonas aeruginosa). The results suggest that the essential oils from the fresh rhizome of Curcuma spp. might be a potential source of natural antimicrobial substances.展开更多
基金supported by the grants from the Biodiversity-Based Economy Development Office Public Organization -National Research Council of Thailand(Grant number.R000012298)Department of Pharmaceutical Sciences,the Faculty of Pharmacy and the Graduate School,Chiang Mai University,Chiang Mai,Thailand
文摘Objective: To investigate chemical constituents and new antimicrobial agents among essential oils from the rhizomes of Curcuma aeruginosa(C. aeruginosa) Roxb., Curcuma glans K. Larsen & J. Mood and Curcuma cf. xanthorrhiza Roxb.Methods: The essential oils were obtained by hydro-distillation and analyzed by gas chromatography/mass spectroscopy. Agar-well diffusion assay was used to study the antimicrobial activity and also broth-micro dilution techniques were examined for minimum inhibitory concentration(MIC) against four bacterial strains and yeast.Results: The gas chromatography/mass spectroscopy analysis showed monoterpenes predominantly(88.53%) in the rhizome oil of Curcuma cf. xanthorrhiza. Sesquiterpenes(50.10%) was the most abundant component in the essential oil of C. glans, while monoterpenes(45.55%) and sesquiterpenes(45.81%) were found in C. aeruginosa with a significant amount. The major components of C. aeruginosa were characterized as camphor(29.39%) and germacrone(21.21%). Germacrone(15.76%), b-pinene(9.97%)and camphor(9.96%) were found as major compounds in the rhizome oils of C. glans while a-terpinolene(24.86%) and p-cymen-7-ol(12.17%) were found as major compositions in Curcuma cf. xanthorrhiza. The essential oils were tested against four bacterial strains and yeast. As a result, the rhizome oil of C. aeruginosa exhibited potent activity against Staphylococcus aureus [inhibition zone(21.94 ± 0.24) mm, MIC 125 μg/mL],Bacillus cereus [inhibition zone(20.83 ± 0.36) mm, MIC 125 μg/mL], and Candida albicans [inhibition zone(11.60 ± 0.30) mm, MIC 250 μg/mL].Conclusions: The essential oils from three Curcuma species possessed greater activity against the gram-positive bacteria(Staphylococcus aureus and Bacillus cereus) than gram-negative bacteria(Escherichia coli and Pseudomonas aeruginosa). The results suggest that the essential oils from the fresh rhizome of Curcuma spp. might be a potential source of natural antimicrobial substances.
