Chemical composition, antioxidant, and antimicrobial activities of six commercial essential oils

Abstract

Essential oils (EOs) and their components extracted from medicinal and aromatic plants are used in several areas, such as perfumery and chemical, cosmetic, food, and pharmaceutical industries. Considering the different applications of EOs, this work aimed to screen the composition and the bioactivities properties of the EOs of Foeniculum vulgare, Helichrysum stoechas, Mentha pulegium, Pinus pinaster, Ruta graveolens, and Thymus mastichina. Gas chromatography–mass spectrometry revealed the presence of different compounds in EOs F. vulgare (12), H. stoechas (27), M. pulegium (8), P. pinaster (24), R. graveolens (8), and T. mastichina (16). All the EOs showed antioxidant activity acting through inhibition of lipid peroxidation, while only two EOs (H. stoechas and M. pulegium) scavenged the free radicals of DPPH. Mentha pulegium and T. mastichina EOs showed the strongest antimicrobial activity. Also, the effect on the fibroblast’s viability was directly proportional to the EOs concentration, and the highest cytotoxic effect was registered with R. graveolens EO. The present study revealed significant bioactive properties of different EOs, highlighting M. pulegium and T. mastichina EOs to be considered in further studies for potential use in the food and pharmaceutical industries, due to their antioxidant and antimicrobial properties.

Antioxidant Activity of Essential Oils from Pinaceae Species

“…For instance, spectrophotometric measurements are usually carried out after maintaining the prepared mixture of sample and free radicals (DPPH) for a particular duration. Although most often this duration was 30 min (e.g., [ 39 , 40 , 43 , 44 , 45 ]), in various published papers, it varied considerably: 10 min [ 46 ], 20 min [ 47 , 48 , 49 , 50 , 51 ], 25 min [ 52 ], 40 min [ 53 ], 50 min [ 42 ], 60 min [ 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ], or 70 min [ 62 ]. Very often, the period after which the spectrophotometric measurements were performed was not mentioned (e.g., [ 63 , 64 , 65 ]).…”

“…A variety of positive controls were used: ascorbic acid [ 47 , 52 , 58 , 70 , 71 , 72 , 73 , 74 ], alpha-tocopherol [ 45 , 52 , 64 , 75 , 76 , 77 ], BHA [ 45 , 55 , 74 , 78 , 79 ], BHT [ 42 , 44 , 45 , 54 , 58 , 67 , 76 , 78 , 80 , 81 ], beta-caryophyllene [ 64 ], caryophyllene oxide [ 64 ], quercetin [ 42 ], tannic acid [ 82 ], gallic acid [ 60 , 83 ], thymol [ 84 ], and even Thymus vulgaris essential oil [ 62 ].…”

“…The beta-carotene bleaching test was less widely used than DPPH, ABTS, or FRAP, but we identified at least eight publications in which it was used on Pinaceae EOs [ 52 , 60 , 62 , 64 , 67 , 68 , 77 , 101 ]. In one variant, the beta carotene–linoleic emulsion was prepared using 0.2 mL of the β-carotene solution (1.0 mg/mL with chloroform as the solvent), 20 μL of linoleic acid, 200 mg of Tween 40, and 50 mL of oxygen-enriched water (oxygen flow at 100 mL/min for 30 min) [ 77 ].…”

“…In addition to the baseline measurement, the UV absorption was measured at 30 and 60 min [ 77 ] and 60 [ 62 , 64 , 101 ], 100 [ 52 ], or 120 min [ 67 , 68 ]. A variety of substances were used as positive controls: ascorbic acid [ 52 , 77 ], alpha-tocopherol [ 52 , 64 , 77 ], BHA [ 67 , 68 ], BHT [ 60 , 67 , 68 ], rutin [ 101 ], Trollox [ 62 ], and Thymus vulgaris EO [ 62 ].…”

Evaluation of Antimicrobial and Cytotoxic Activity of Nanoformulated Chamomile and Green Tea-Based Mouthwash: An In Vitro Study

“…By combining these two, a synergistic effect can be harnessed [9]. Chamomile tea contains bioactive compounds, i.e., flavonoids and terpenoids, which have notable antimicrobial effects against numerous pathogens [10]. In addition, studies have demonstrated the inhibitory effects of chamomile extracts on bacterial growth, indicating their potential as a natural antimicrobial agent [11].…”