Phytochemical Compositions and Biological Activities of Essential Oils from the Leaves, Rhizomes and Whole Plant ofHornstedtia bellaSkornick

The rapid emergence of drug-resistant strains and novel viruses have motivated the search for new anti-infectious agents. In this study, the chemical compositions and cytotoxicity, as well as the antibacterial, antifungal, antitrichomonas, and antiviral activities of essential oils from the leaves, rhizomes, and whole plant ofHornstedtia bellawere investigated. The GC/MS analysis showed that beta-pinene,E-beta-caryophyllene, and alpha-humulene were found at high concentrations in the essential oils. The essential oils exhibited (i) inhibition againstStaphylococcus aureus,methicillin-resistantStaphylococcus aureus,Staphylococcus epidermidiswith minimum inhibitory concentrations (MIC) and minimum lethal concentration (MLC) values from 1 to 4% (v/v); (ii) MIC and MLC values from 2 to 16% (v/v) inCandida tropicalisandCandida parapsilosis; (iii) MIC and MLC values from 4 to 16% inEnterococcus faecalis; and (iv) MIC and MLC values from 8 to greater than or equal to 16% (v/v) in the remaining strains, includingEscherichia coli,Pseudomonas aeruginosa,Klebsiella pneumoniae,Candida albicans,andCandida glabrata. In antitrichomonas activity, the leaves and whole-plant oils ofHornstedtia bellapossessed IC50, IC90, and MLC values of 0.008%, 0.016%, and 0.03% (v/v), respectively, whilst those of rhizomes oil had in turn, 0.004%, 0.008%, and 0.016% (v/v).Besides, the leaf oil showed a weak cytotoxicity against Vero 76 and MRC-5; meanwhile, rhizomes and whole-plant oils did not exert any toxic effects on cell monolayers. Finally, these oils were not active against EV-A71.