Chemical Composition and Antimicrobial Activities of the Essential Oils from Ocimum Selloi and Hesperozygis myrtoides

Abstract

Ocimum selloi, a traditional medicinal plant from Brazil, is sold in open-air markets at Rio de Janeiro State. Hesperozygis myrtoides is a very aromatic small bush found in the State of Minas Gerais, Brazil, growing at an altitude of 1800m. The chemical composition of both essential oils was analyzed as well as their antimicrobial activity against fungi and bacteria. For all specimens of Ocimum selloi obtained at open-air markets, methylchavicol was major compound found (93.6% to 97.6%) in their essential oils. The major compounds identified in the oil of H. myrtoides were pulegone (44.4%), isomenthone (32.7%), and limonene (3.5%). Both oils displayed antimicrobial activity against all tested microorganisms but Candida albicans was the most susceptible one. Combinations of the two oils in different proportions were tested to verify their antimicrobial effect against C. albicans, which, however, was not modified in any of the concentrations tested. The minimum inhibitory concentration (MIC) was determined to confirm the antimicrobial activity against C. albicans as well as other clinical isolates (C. glabrata, C. krusei, C. parapsilosis and C. tropicalis).

Chemical characterization by GC-MS and in vitro activity against Candida albicans of volatile fractions prepared from Artemisia dracunculus, Artemisia abrotanum, Artemisia absinthium and Artemisia vulgaris

“…However in another study, davanone as single compound showed only very weak in vitro activity against C. albicans [ 29 ]. Candida albicans proved to be very susceptible against the essential oil from Ocimum selloi which contains more than 95% estragole (= methylchavicol) [ 30 ]. However, in another test series, estragole as single substance proved to be ineffective [ 31 ].…”

Chemical and Biological Diversity in Fourteen Selections of Four Ocimum Species

“…Essential oils of Ocimum species possess antibacterial and antifungal activities [3,[17][18][19][20][21][22], but differences in these have been observed [23,24]. Indian O. basilicum oil was not active against E. coli [25], while Congo oil was [26].…”

“…Ocimum oils are rich in oxygenated monoterpenes (camphor, linalool) and phenylpropanoids (eugenol, methyl eugenol, methyl chavicol, methyl cinnamate, and thymol) [15,16]. Essential oils of Ocimum species possess antibacterial and antifungal activities [3,[17][18][19][20][21][22], but differences in these have been observed [23,24]. Indian O. basilicum oil was not active against E. coli [25], while Congo oil was [26].…”

Structural characterization of vegetative organs of the endangered Brazilian native species Hesperozygis ringens (Benth.) Epling

“…In addition, the oxygenated monoterpenoid pulegone has been reported as its major compound and different authors attributed the activities detected for this extractive especially to this molecule (Von Poser et al 1996, Ribeiro et al 2010, Toni et al 2014, Pinheiro et al 2016, 2017. Studies regarding this species as well as other Hesperozygis representatives usually focus on essential oil production, describing their chemical characteristics and possible activities for the plant extractives (Von Poser et al 1996, González-Chavez et al 2011, Martini et al 2011, Castilho et al 2016. Despite the chemical importance of the genus, little information is known on the structural characterization of its species.…”