Chemical profiling and determination of antioxidant and antibacterial properties of selected essential oils

Abstract

Aromatherapy is a complementary therapy that is popularly known as massage treatment in the field of Somatology. Its holistic effects on emotional and physical well-being have gained interest in the cosmeceutical industry. Various studies have been conducted to search for advanced novel compounds with improved chemical composition and properties. The purpose of the present study was to assess the chemical composition of the essential oils extracted from Citrus var. arauntium, Lavendula augustofilia, Citrus arauntium var. bergamia, Artemisia afra, Petroselinum crispum, Matricaria chamomilla, Salvia stenophylla, and Ocimum basilicum. The composition of the oils of these plants was analysed using gas chromatography mass spectrometry (GC-MS). The results revealed a range of between 13-49 compounds in the eight oils tested, and these compounds represented between 97.24-100% of the oils. Some of the same compounds were detected in the eight the oils, but the percentages of their presence differed greatly. Some compounds were dominant in some oils, while they were present in minimal quantities in others. The overall profile of the compounds is as follows: • thujone (69%), thujene (14.8%), and pinene (0.18-0.87%) were detected in A. afra. • phenethyl alcohol (26.23%), linalyl anthranilate (26.56%), and D-limonene (7.33-27.4%) were detected in C. aurantium var. amara; • myrcene (0.17-0.27%), bisabalol (0.29-10.50%), cymene (0.19-2.81%), and eucalyptol (0.59-11.86%) were detected in S. stenophylla; • linalyl acetate (48.43%), D-limonene, and sabinene (0.14-0.53%) were detected in C. aurantium var. bergamia; while • linalyl butyrate (29.1%) was detected in lavender. • Both Ocimum bacilicum and Lavendula angustofolia contained estragole (79%) and linalool (3.9-27.9%); while • Petriselinum crispum contained salinene (6.14-26.33%) and apiole (11.82%). • M. chamomilla had 9-Amino-1-phenyl-3,6-diazahomoadamantane (10.59%) and some unknowns. The detection of these unknown dominant compounds could mean that the oil was adulterated or that the compounds were not available in the GC-MS library. The findings of these analyses may serve as a guide for the selection of ideal oils for an intended treatment. The chemical composition of oils extracted from lavender, neroli, bergamot, chamomile, and sweet basil have been investigated in earlier studies as well, and adulterants like linalool, linalyl acetate, terpineole, pimaric acid, and abietic acid have been reported.