Open access peer-reviewed chapter

Essential Oils High in 1,8-Cineole of Mediterranean Flavoring Plants: Health Benefits

Written By

Sílvia Macedo Arantes, Ana Teresa Caldeira and Maria Rosário Martins

Submitted: 11 February 2022 Reviewed: 21 February 2022 Published: 02 June 2022

DOI: 10.5772/intechopen.103831

From the Edited Volume

Essential Oils - Advances in Extractions and Biological Applications

Edited by Mozaniel Santana de Oliveira and Eloisa Helena de Aguiar Andrade

Chapter metrics overview

291 Chapter Downloads

View Full Metrics

Abstract

Aromatic flavoring plants are important ingredients of the Mediterranean diet, one of the healthiest and most sustainable dietary forms, often associated with greater longevity as well as contributing to the reduction of some chronic pathologies with high mortality and morbidity. Their essential oils (EOs) are increasingly used as therapeutic agents and food supplements, due to their antioxidants, anti-inflammatory or anti-tumoral properties. The Health benefits of essential oils are closely related with their chemical constituents. The 1,8-cineole, a naturally cyclic oxygenated monoterpene, has been attributed several biological properties such as antioxidants, anti-inflammatory or antitumoral. Nevertheless, the EO properties are attributed not only to their main components but also to the synergistic effect of minor components. This review chapter focused on the chemical composition and antioxidant and anti-inflammatory potential of EOs of flavoring Lamiaceae plants, with high content in 1,8-cineole, including chemotypes of genera Lavandula, Calamintha, Rosmarinus, and Thymus, often used in the Mediterranean diet.

Keywords

  • natural products
  • 1
  • 8-cineole
  • antioxidants
  • anti-inflammatory properties

1. Introduction

Aromatic plants are increasingly used as therapeutic agents and as food supplements, along with industrial synthesis products. The World Health Organization (WHO) estimates that more than 80% of the world population uses products based on plant extracts and/or their active components for various purposes, including health care and phytotherapy [1, 2, 3].

Essential oils (EOs) are volatile compounds, products of secondary metabolic processes of aromatic plants and despite being practically insoluble in water, can be carried away by water vapor. They are largely obtained by water distillation or using steam distillation, from different parts of the plant, including the whole plant or just the wood, roots, leaves or flowers [4, 5]. Other processes to obtain oils from plants include expression, solvent extraction, CO2 extraction, maceration, cold pressure extraction [6]. Indeed, the species, the plant geographical conditions, and the part of the plant used as well as the extraction method used will be determinants for the EOs chemical profile [7, 8, 9, 10, 11]. Otherwise, in the distillation process, thermal degradation of sensitive compounds, the photo-oxidation of light-sensitive compounds or the hydrolysis of esterified compounds are factors that can affect the chemical profile of EOs [7, 8, 9, 10, 11, 12].

Aromatic, spice and medicinal plants are part of the Mediterranean diet, recognized by the WHO as a healthy and health-promoting type of diet [1, 2]. They also represent a growing interest in the food industry and are often used in alternative or complementary therapies in conventional medicine [13, 14]. Due to their effectiveness and, mainly, due to the lower number of adverse effects, when compared to synthetic drugs, the use of aromatic plants as functional foods as well their EOs may be an important role in the prevention of pathologies with high mortality and morbidity, such atherosclerosis, neurodegenerative diseases, diabetes, several infections, chronic inflammatory diseases, cancer and autoimmune diseases [15, 16, 17, 18, 19, 20]. Some flavoring plants used in the Mediterranean diet are frequently used in Alentejo (South of Portugal) as food additives or flavors. Most of them belong to the Lamiaceae family and include Lavandula spp., Calamintha spp., Rosmarinus spp. and Thymus spp., in which EOs show chemical polymorphism with high content in 1,8-cineole and that are recognized for their antioxidant and anti-inflammatory potential [21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36].

The genus Lavandula comprises about 32 species, commonly known as lavender, such as L. angustifolia and L. latifolia, as well as Mediterranean L. stoechas, L. pedunculata and L. viridis, often found in the southern region of Portugal. Due to their great diversity, some species have a difficult taxonomic classification due to their hybridization capacity and morphological diversity, being important to characterize them by the composition of their OEs due to their great economic importance. Lavandula EOs are generally produced by distillation, either from the flower spike or from the leaves [37, 38, 39]. Lavandula. stoechas L. subsp. luisieri (Rozeira) Rozeira, Lavandula pedunculata (Mill.) Cav. and Lavandula. viridis L’Hér, are endemic to the Iberian Peninsula and wild growth in some regions the southern region of Portugal [40]. L. luisieri and L. pedunculata can be distinguished mainly by the shapes of the bracts the length of the stalks of the ears as well as by the diversity of their EOs components [21, 41, 42]. L. viridis, known as green lavender or white lavender, and their EOs showed antioxidant and anti-inflammatory activities, depending on the plant polymorphism and the EO chemotype [4, 21, 43, 44, 45, 46].

The genus Calamintha consists of eight native species belonging to the Lamiaceae family, of which six species are extremely polymorphic [47]. Calamintha nepeta subsp. nepeta (syn. Clinopodium nepeta (L.) Kuntze) commonly known as neveda or calamint, is a perennial and quite aromatic plant and is widely distributed in the Mediterranean area [4, 40]. It is well known as a spice used in food flavoring and as an antiseptic and diuretic stimulant [48]. It is traditionally used in medicine as an antitussive and expectorant; it also has spasmolytic and anti-flatulence properties [49, 50]. Some studies report that its EO has antifungal and antibacterial activity, due to the high content of terpene derivatives [48]. It has also been reported that the EOs of this species have antioxidant, antimicrobial, anti-inflammatory and sedative properties [51, 52, 53, 54].

The genus Rosmarinus (Lamiaceae) that grows wild in the western Mediterranean region is composed of three different species: Rosmarinus officinalis, Rosmarinus eryocalix and Rosmarinus tomentosus [55, 56]. Rosmarinus officinalis L. (Syn: Salvia rosmarinus Schleid and Rosmarinus angustifolius Mill) commonly known as rosemary is widely used worldwide and is indigenous from the Mediterranean region, spontaneous in heaths, thickets and pine forests in the Center and South of the Continent [57, 58, 59]. Hepatoprotective, antioxidant and antimicrobial effects are attributed to this medicinal plant, as well as action in rheumatic diseases and digestive problems [59, 60].

The genus Thymus (Lamiaceae), also widely distributed in the Iberian Peninsula, is a taxonomically complex group of aromatic plants, traditionally used for medicinal purposes and contains about 214 species throughout the world [61, 62, 63, 64, 65, 66, 67]. Thymus mastichina (L.) is an endemic species of the Iberian Peninsula and it is found from north to south of Portugal (generally at the interior north and at the south) [4]. Commonly known as mastic thyme or Spanish marjoram, it is characterized by simple and opposite leaves and zygomorphic and bilabial flowers. Thymus mastichina L. subsp. mastichina has great ecological plasticity and is usually present in clearings of xerophytic bushes, roadsides, and slopes, abandoned fields, pine forests, cork oaks, stony areas and rocky outcrops. They prefer removed substrates, generally siliceous, quite sandy, and also schist and limestone substrates [68]. It is widely used for its medicinal properties, including antiseptic, digestive, antirheumatic, antispasmodic, expectorant and antitussive effects, and is also used as a flavoring plant in perfume and cosmetics industry [4, 68, 69]. Thymus capitellatus Hoffmanns & Link, commonly known as “wild-thyme”, is an aromatic species endemic to the southern of Portugal, growing in sandy substrates of the Tagus and Sado basins (Extremadura, Ribatejo and Alentejo provinces of Iberian Peninsula) [70].

Advertisement

2. Inter- and intra-specific differences in EOs compositions

EOs are an important source of bioactive compounds with application in phytotherapy and traditional medicine. They are volatile complex compounds characterized by a strong odor and are rich in terpene compounds, namely monoterpenes (C10) and sesquiterpenes (C15), although diterpenes (C20) may also be present, as well as a variety of low molecular weight aliphatic hydrocarbons, acids, alcohols, aldehydes, acyclic esters or lactones and, exceptionally, compounds containing nitrogen (N) and sculpture (S), coumarins and phenylpropanoid homologs [6, 71, 72].

Among the different terpenes present in EOs, 1,8-cineole or eucalyptol (1,3,3-trimethyl-2-oxabicyclo [2.2.2] octane) in cyclic monoterpene oxide with a strong odor well known as the major constituent (>70%) of diverse eucalyptus species [73, 74, 75, 76, 77, 78]. Some studies have demonstrated the high pharmacological potential of 1,8-cineole, namely as an antioxidant and anti-inflammatory compound [73, 74, 75, 76, 77, 78, 79, 80, 81]. With no negative effects in animal experiments, 1,8-cineole is considered safe when administered at normal doses (very high value of LD50 in rats - between 1.5 and 2.5 g/kg) [82]. Nevertheless, EOs of some Lamiaceae flavoring plants showed high content in 1,8-cineole, such as some lavenders (Lavandula ssp.) [21, 22, 23, 25, 42, 43, 45, 83, 84, 85, 86, 87, 88, 89, 90], rosemary (Rosmarinus officinalis) [29, 30, 58, 91], Calamintha nepeta [26, 27, 50, 92, 93] and some thymes (Thymus mastichina [26, 27, 36, 94, 95] and Thymus capitellatus [70, 96]).

Due to their natural function, the chemical composition of EOs is determined not only by the genus, species, and subspecies of an aromatic plant but also by external factors such as geographic location, environmental conditions of the region, cultivation conditions, season and time of harvest [7, 8, 9, 10]. In addition, it is also necessary to consider some procedures, such as techniques of plant collection or post-harvest conservation, part of the plant used, and the EOs extraction method also affects the chemical composition of EOs [7, 8, 9, 10].

Table 1 presents some of the main components of EOs of aromatic plants from the Mediterranean region of the genera Lavandula, Calamintha, Rosmarinus and Thymus, described in the bibliography. EOs of these flavoring plants present polymorphisms and, consequently, it is possible to find at least two or three chemotypes.

EOCountryPart usedMajor volatile compoundsRef.
Lavandula luisieriPortugal (Algarve)Flowering aerial parts1,8-Cineole (26–34%);
α-Necrodyl acetate (11–18%)
[21]
Portugal (Penamacor)Flowers1,8-Cineole (3–4%); Camphor (8–21%); Linalool (1.4–3%); α-Necrodil acetate (2–20%)[22]
Portugal (Penamacor)Leaves1,8-Cineole (13.9–16.4%); Camphor (1–3%);
Linalool (1–2%); α-Necrodil acetate (8–19%)
[22]
Portugal (Alentejo)Flowering aerial parts1,8-Cineole (19%); α-Necrodyl acetate (16%);
Lavandulol (12%); α-Necrodol (11%);
β-Caryophyllene (6%)
[23]
Portugal
(Piódão region)
Flowering aerial parts1,8-Cineole (6.4%); α-Necrodyl acetate (17%)[83]
Portugal
(Algarve)
Flowering aerial parts1,8-Cineole (34%); Fenchone (18%);
α-Necrodyl acetate (3%)
[83]
Spain
(Toledo; Sevilha)
Flowering aerial parts1,8-Cineole (0.4–21%); Fenchone (1.4–22%);
Camphor (2–54%)
[84]
Spain
(Sevilha)
Flowering aerial partsα-Necrodol, α-Necrodyl acetate and 1,8-Cineole, (>50%)[85]
SpainLeaves flowersCamphor (81%); 1,8-Cineole (77%)
Camphor (88%); 1,8-Cineole (85%)
[86]
Spain
(Sevilha)
Flowering aerial parts1,8-Cineole (16%); α-Necrodyl acetate (23%)[87]
PortugalFlowering parts1,8-cineole (6–34%); fenchone (0–18%); α-Necrodyl acetate (3–17%);[88]
Lavandula pedunculataPortugal (Algarve)Flowering aerial partsFenchone (42–44%); Camphor (35–36%)[21]
Portugal (Algarve)Flowering aerial partsCamphor (41%); Fenchone (38%)[25]
Portugal
(Santarém)
Flowering aerial partsFenchone (62–70%); 1,8-Cineole (6–28%)[89]
Portugal
(Trás-os-Montes)
Flowering aerial parts1,8-Cineole (24%); Camphor (32.4%)[42]
Portugal (Coimbra)Flowering aerial partsFenchone (49%); α-Pinene (5%); α-Cadinol (4%)[42]
Portugal (North and Center)Flowering aerial parts1,8-Cineole (2.4–56%); Fenchone (1.3–60%);
Camphor (4–48%)
[90]
PortugalFlowering parts1,8-Cineole (12–34%); fenchone (6–50%); Camphor (10–34%);[88]
Lavandula viridisPortugal (Algarve)Flowering aerial parts1,8-Cineole (35%); Camphor (13%);
α-Pinene (9%)
[45]
Portugal (Algarve)Flowering aerial parts1,8-Cineole (33%); Camphor (20%)[21]
Portugal (Algarve)Flowering aerial parts;1,8-Cineole (18–25%); Camphor (9–12%);
Borneol (4–5%); α- terpineol (1–4%)
[43]
Calamintha nepetaPortugal (Algarve)Aerial parts1,8-Cineole (30%); Isopulegone (36%)[26]
Portugal (Alentejo)Flowering aerial parts1,8-Cineole (28%); Menthone (22%);
Menthol (16.3%)
[27]
Italy (Basilicata region)Flowering aerial partsPulegone (45%); Menthone (16%);
Piperitenone (13%); Piperitone (6%)
[92]
Italy (Sardinia Island)Flowering aerial partsPulegone (40–64%); Piperitenone (6–8%); Piperitenone oxide (2.5–19%)[50]
PortugalFlowering aerial partsIsomenthone (36–51%);
1,8-Cineole (21%);
trans-Isopulegone (6–8%)
[50]
SerbiaFlowering aerial partsPulegone (76%)[93]
Rosmarinus oficinallisSi Chuan Province, ChinaAerial parts1,8-Cineole (27%); α-Pinene (19%); Camphor (14%); Camphene (12%); β-Pinene (7%)[29]
IranAerial partsα-Pinene (15%); 1,8-Cineole (7%);
Linalool (15%),
[30]
Portugal (Vila Real)Aerial parts1,8-Cineole (23–67%)[58]
AlgeriaLeaves and stems1,8-Cineole (leaves: 54%,stem: 30%)[91]
Thymus mastichinaPortugal (Algarve)Flowering aerial parts1,8-Cineole (47–61%)[94]
Portugal (Algarve)Aerial parts1,8-Cineole (41%)[26]
ItalyMicropropa-gated plantlets1,8-Cineole (58%); Linalool (25%)[95]
Spain (Murcia)Flowering aerial parts1,8-Cineole (39–74%); Linalool (2.2–43%)[36]
Portugal (Alentejo)Flowering aerial parts1,8-Cineole (71%)[27]
Thymus capitellatusPortugal (Ribatejo)Aerial parts
(flowering)
1,8-Cineole (59%); Borneol (10%)[96]
Portugal
(Porto Alto)
Aerial parts1,8-Cineole (48%)[70]
Portugal (samora Correia)Aerial parts1,8-Cineole (29%); Borneol (29%)[70]
Portugal (Poceirão)Aerial parts1,8-Cineole (28%); Linalyl acetate (20%);
Linalool (17%)
[70]

Table 1.

Main components present in some EOs of flavoring plants.

Some studies report that L. luisieri EOs has a unique composition in the Plantae kingdom, containing irregular cyclopentene monoterpenes derived from necrodane, such as α-necrodol, α-necrodyl acetate; in addition to, 1,8-cineole, lavandulyl acetate, α-pinene, linalool, camphor and fenchone [83, 86, 87, 97]. However, the chemical compositions of the EOs of L. stoechas subsp. stoechas and L. stoechas subsp. luisieri are quite distinct [85, 87], so this classification has been controversial studies carried out with the EOs of L. luisieri from southern Portugal, revealed a chemical profile rich in oxygenated monoterpenes (>50%) and hydrocarbons sesquiterpenes (5–11%), of which 1,8-cineole (18.8%), trans-α-necrodyl acetate (16.2%), lavandol (11.7%), trans-α-necrodol (10.6%), and β-caryophyllene (6.0%) [23]. Recently, a study with EOs of L. luisieri and L. pedunculata from Portugal reported EOs of L. luisieri with 1,8-cineole (6–34%); fenchone (0–18%) and α-Necrodyl acetate (3–17%); and L. pedunculata with major compounds 1,8-Cineole (12–34%); fenchone (6–50%) and camphor (10–34%) (three chemotypes: 1,8-cineole, fenchone and camphor) [88]. In studies carried out by Garcia-Vallejo, et al. [98] and Lavoine-Hanneguelle and Casabianca [87] with L. luisieri from Spain, the EOs presented as main compounds 1,8-cineole, lavandulol, lavandulyl acetate, linalool and their acetates, also present in other species of the genus Lavandula, in addition to some necrodane compounds. According to Miguel et al. [21] the populations of Spain showed high levels of 1,8-cineole, fenchone, camphor and necrodane derivates and, in the south of Portugal, the majority compound it was always the 1,8-cineole [84, 86].

EO of L. pedunculata showed high content of oxygenated monoterpenes, although with quantitative differences regarding the percentages of the various compounds [21, 90]. Studies carried out with L. pedunculata from central Portugal [90] indicate that its EO consists mainly of oxygenated monoterpenes (69–89%) and hydrocarbons monoterpenes (4.25–22.5%), with fenchone as the main constituents (1.3–59.7%), 1.8-cineole (2.4–55.5%) and camphor (3.6–48.0%). The EOs of L. pedunculata from central Portugal have been categorized into three chemotypes: 1,8-cineole, 1,8-cineole/camphor and fenchone [35], while the EO of L. pedunculata from the Algarve (Portugal) expresses the camphor/camphene chemotype [25].

Analysis of the EO of L. viridis revealed a chemical composition with a predominance of terpenoids, namely oxygenated monoterpenes (>50%) and hydrocarbons monoterpenes (>20%) and sesquiterpenes (<5%), presenting as majority: 1,8-cineole, camphor, α-pinene and linalool, the leaves of which are used, dried, in medical applications in Madeira, Portugal [43, 44, 45, 46]. Some authors relate that the EO of the aerial part (leaf and flower) of this species contains mostly oxygenated monoterpenes (>50%), hydrocarbons monoterpenes (>20%) and sesquiterpenes (<5%), presenting as major compounds: 1,8-cineole (22–42%), camphor (2.9–31.5%), α-pinene (0.3–14.4%) and linalool (0.2–7.8%) [21, 43, 44, 45].

Depending on the variety and region, Calamintha EOs showed as major components carvacrol (45–65%), β-pinene, geraniol, α-caryophyllene and pulegone [48, 49, 50]. Previous studies with EOs oils from C. nepeta indicate the presence of a remarkable chemical polymorphism, suggesting the existence of two chemotypes: one characterized by the predominance of pulegone and menthone, menthol and/or its isomers, piperitenone, piperitone and their oxides [93, 99, 100, 101, 102, 103, 104, 105], and the other type characterized by the predominance of piperitenone oxide and/or piperitone oxide [93, 106]. Marongiu et al. [50], in a study comparing the chemical profile carried out with Portuguese and Italian C. nepeta, reported that the EO of Portuguese C. nepeta presented as major components isomenthone, 1,8-cineole and isopulegone, while the Italian EO presented pulegone as a major component. Studies carried out with C. nepeta from southern Portugal reported that this EO had 1,8-cineole, isopulegol and isopulegone as major components [26]. Studies carried out with C. nepeta EOs from Alentejo (Portugal) have shown a peculiar chemical profile predominantly composed of isomenthone (35.8–51.3%), 1,8-cineole (21.1–21.4%) and trans-isopulegone (7.8–6.0%) [27, 28, 107, 108, 109].

Rosmarinus EOs present α-pinene (up to 30%), β-pinene, camphene, limonene, myrcene, β-caryophyllene, cineole (15–30%), camphor (15–25%) as major compounds [4, 34]. The EO of R. officinalis presents a chemical polymorphism. In studies carried out by Ribeiro et al. [58], Wang et al. [29] and Boukhobza et al. [91] with the EO of R. officinalis from Portugal, China and Algeria, respectively, the EO presented as the majority compound 1,8-cineole. The EO of R. officinalis from Iran presented, as major components, α-pinene and linalool, with 14% each [30].

Thymus vulgaris, a flowering plant from genus Thymus and originating in southern Europe, is characterized by chemical component polymorphism according to the main volatile, with known six EOs chemotypes: geraniol, linalool, α-terpineol, tujanol-4, thymol and carvacrol [110]. T. mastichina is a related species to the Thymus genus but it presents a chemical polymorphism, with 1,8-cineole, limonene and β-terpinol as main constituents [4]. According to Salgueiro et al. [111], the EOs of some thyme species were characterized by a high content of 1.8-cineole and variable content of linalool, which varies with the geographical origin. Another study with EOs from T. mastichina reported 1,8-cineole (64%) as a major component, followed by α-terpineol (6%) and β-pinene (5%) [4, 112]. Moreover, Portuguese thyme from the T. mastichina section has also 1,8-cineole as the main constituent (often higher than 60%) [111]. Studies with a related species, T. capitellatus reveal the existence of polymorphisms in their EOs, reporting three chemotypes: the 1,8-cineole; the 1,8-cineole/borneol and the 1,8-cineole/linalyl acetate/linalool chemotypes [70].

Advertisement

3. Health benefits of EOs

Plants and their extracts have been used by mankind since the beginning of history and their secondary metabolites have traditionally played an important role in human health and well-being [71], increasingly important in therapeutics, due to their efficacy and, above all, due to the lower number of adverse effects when compared to synthetic drugs.

Table 2 reports some pharmacological activities (antioxidant analgesic, anti-inflammatory and cholinesterase inhibition) of EOs of some Lavandula spp., Calamintha nepeta, Rosmarinus officinallis and Thymus mastichina chemotypes high in 1,8-cineole. Depending on their chemical composition, either major and minor constituents, studies report antioxidant, antitumor, analgesic and anti-inflammatory, sedative or antispasmodic effects of these EOs [72, 113].

EOsBiological activitiesRef.
Lavandula luisieriAntioxidant and analgesic or anti-inflammatory potential[21, 22, 23, 24, 88]
Lavandula pedunculataAntioxidant activity and cholinesterases inhibition[21, 25, 88]
Lavandula viridisAntioxidant activity[21]
Calamintha nepetaAntioxidant and Antitumoral potential[26, 27, 28]
Rosmarinus oficinallisAntioxidant activity and acetylcholinesterase inhibition; Antiproliferative activities[29, 30, 31, 32, 33, 34, 35]
Thymus mastichinaAntioxidant potential and Acetylcholinesterase inhibition, Lipoxygenase inhibition and anti-tumoral activities[26, 27, 36]

Table 2.

Biological properties of EOs with high content in 1,8-cineole.

3.1 Antioxidant activity of EOs

The adverse effects of oxidative stress on human health have become a serious issue. This results from the imbalance between oxidant and antioxidant molecules, which can induce cellular damage by free radicals and promote the development of many current disease conditions, including inflammation, autoimmune diseases, cataracts, cancer, Parkinson’s disease, arteriosclerosis and aging [1, 114]. Reactive oxygen species (ROS) are constantly generated and play important roles in a variety of normal biochemical functions as well as irregular or pathological processes. Furthermore, ROS can be produced by a family of mitochondrial membrane-bound enzymes, such as NAD(P)H oxidases, which appear to affect cell proliferation and apoptosis [115].

A broad definition of an antioxidant is “any substance which, present in low concentrations compared to that of the oxidizable substrate, effectively delays or inhibits the oxidation of that substrate”. EOs are important antioxidants able to prevent or minimize the development of degenerative diseases, including cardiovascular diseases, cancer, neurodegenerative and inflammatory diseases [1].

Many of the medicinal plants belonging to the Lamiaceae family have antioxidant potential. Studies carried out with medicinal plants suggest that their antioxidant activity is due to the redox reactions of phenolic compounds, which allow them to act as reducing agents, donating hydrogen atoms and capturing singlet oxygen [116].

Some studies carried out with species of the genus Lavandula suggests that EOs from the aerial parts of these plants have antioxidant activity in protecting the lipid substrate and capturing free radicals, depending on their chemical constituents [21, 22, 37, 117, 118].

EOs of C. nepeta from Portugal have in vitro antioxidant capacity either to capture free radicals and to reduce Fe3+ or inhibit lipid oxidation [26, 27, 28]. Also, the EO of R. officinallis with high content of 1,8-cineole reported that it could inhibit lipid peroxidation and capture free radicals [29, 31, 32, 34]. Studies carried out with T. mastichina EOs from Spain and Portugal showed that their EOs have shown low antioxidant activity by the DPPH radical method [26, 36, 119].

EOs are an important source of potentially useful antioxidants to prevent oxidative stress and promote human health [120]. According to the literature, the antioxidant activity of EOs is related to their high content of monoterpenes, namely limonene, 1,8-cineole, γ-terpinene, α-terpinene, linalool, 4-terpineol [60, 121, 122]. Additionally, the synergistic potential of minority constituents is often proposed to explain the differences between estimated and observed values for antioxidant capacities [123, 124]. Antioxidant properties of EOs also suggest their potential as anti-inflammatory agents, since the capture and elimination of free radicals is one of the mechanisms involved in the prevention of inflammation [125, 126]. Additionally, due to their high activity in protecting the lipid substrate, EOs have the potential to prevent neurodegenerative and cancerous diseases [35, 127].

3.2 Anti-inflammatory activity of EOs

The inflammatory response is one of the most important defense mechanisms of the body, responsible for removing and neutralizing invading microorganisms and/or repairing tissues, involving, in its processes, immune cells of the hematopoietic system, such as macrophages. Cyclooxygenases (COX) play an important role in mediating the body’s inflammatory response [128, 129, 130]. Cytokines released in the anti-inflammatory processes (IL-1, IL-2, IL-6, IL-8 and TNF or tumor necrosis factor) are also associated with other body responses, including immune and anti-inflammatory responses or anti-tumoral and apoptosis processes [131, 132, 133, 134].

EOs of several plants promote anti-inflammatory activity due to the presence of bioactive compounds such as oxygen monoterpenes that mediate the capture of free radicals generated by neutrophils and macrophages as well as for their ability to inhibit the cyclooxygenase pathway, having an important role in the regulation of inflammatory mediators [126, 135]. There is evidence that the association of chronic inflammation and oxidative stress with the aging process, indicating a subclinical chronic response. Additionally, the presence of reactive species in inflammatory processes are present in the etiology of several pathologies, including those resulting from metabolic disorders, demonstrating the central role of the reciprocal interaction between oxidative stress and inflammation [136, 137, 138, 139, 140, 141].

The anti-inflammatory activity of EOs can be attributed not only to their antioxidant properties but also to interactions with signaling cascades involving cytokines and transcriptional regulatory factors and in the expression of pro-inflammatory genes [126, 142]. Some studies carried out in animal models with terpenes present in EOs, such as linalool, limonene, myrcene, 1,8-cineole, demonstrated that these compounds showed analgesic activity [143, 144, 145, 146, 147, 148, 149, 150, 151, 152]. The analgesic and anti-inflammatory potential of OEs are preferentially attributed to the high content of terpene compounds [143, 145, 146, 153, 154, 155, 156] as well as to the synergetic effect of minor components that can influence the pharmacokinetics and bioavailability of compounds with pharmacological action [157].

The anti-inflammatory effects observed for the EOs of Lavandula species can be attributed to their monoterpene content, namely 1,8-cineole, fenchone, linalool [143, 144, 145, 146, 147, 152]. For example, a study with EO from the leaves of L. angustifolia, high in 1,8-cineole (65%), borneol (12%) and camphor (10%) reported EO anti-inflammatory activity of 48% at a dose of 200 mg/kg [38]. In another case, Cardia et al. [158] demonstrated that the EO of L. angustifolia has anti-inflammatory activity by the method of paw edema induced by carrageenan, being able to inhibit, at a dose of 100 mg/kg, the inflammation in 54%, 56% or 45% after 30, 60 or 120 min, respectively. Recently, Zuzarte et al. [88] evaluated the anti-inflammatory activity of EOs of L. luisieri (high content in 1,8-cineole and fenchone and low quantities of necrodane derivatives) and three different EOs chemotypes of L. pedunculata (1,8-cineole, fenchone and camphor chemotypes) from Portugal and reported that EOs of L. luisirei, rich in 1,8-cineole and fenchone, was the EO with the highest anti-inflammatory potential and also was more active than its major compounds when assessed alone or in combination, confirming the synergetic effect of minor components.

Regarding the species of the genus Thymus, the most studied species is T. vulgaris, being widely recognized for the potential of its EOs and their major components as anti-inflammatory agents [159, 160, 161]. On the other hand, the literature reports that the monoterpenes 1,8-cineole, anethole and fenchone, major components present in the EOs of C. nepeta and T. mastichina may be also responsible for the anti-inflammatory effect [77, 143, 144, 147, 148, 149, 150, 151, 152, 162].

Advertisement

4. Conclusions

EOs are increasingly used as therapeutic agents, cosmetics and food additives, along with industrial synthesis products, with application in phytotherapy. However, several factors can affect the biological properties of OEs, such as genera and species, time and region of harvest, extraction method, as well as the polymorphisms of each species. Correlation study between the biological properties of EOs and their chemical composition allows to evaluate its phytopharmaceutical potential and, together with traditional knowledge and practices, scientifically validate it, to allow an adequate, effective and safe use.

The biological activities of EOs are often related with its high content of some monoterpenes, such as 1,8-cineole which is an oxygenated monoterpene frequently found as one of the major components in the EOs of some plants of genera Lavandula, Calamintha, Rosmarinus and Thymus, autochthonous to the Mediterranean region. Several biological properties of EO of these plants have been attributed, including antioxidant (capacity to capture of free radicals or ability to protect the lipid substrate) and anti-inflammatory properties. These EOs properties are often attributed to their major components, however, the synergistic potential of minor constituents is often proposed to explain the differences between estimated and observed values.

Advertisement

Acknowledgments

This work was supported by the UIDB/04449/2020 and UIDP/04449/2020 projects, funded by Fundação para a Ciência e Tecnologia (FCT).

Advertisement

Conflict of interest

The authors declare no conflict of interest.

References

  1. 1. Krishnaiah D, Sarbatly R, Nithyanandam R. A review of the antioxidant potential of medicinal plant species. Food and Bioproducts Processing. 2011;89(C3):217-233
  2. 2. Ssegawa P, Kasenene JM. Medicinal plant diversity and uses in the Sango bay area, Southern Uganda. Journal of Ethnopharmacology. 2007;113(3):521-540
  3. 3. Kumar V, Marković T, Emerald M, Dey A. Herbs: Composition and dietary importance. In: Caballero B, Finglas PM, Toldrá F, editors. Encyclopedia of Food and Health. Oxford: Academic Press; 2016. pp. 332-337
  4. 4. Cunha AP, Ribeiro JA, Roque OR. Plantas aromáticas em Portugal: Caracterização e Utilizações. Lisboa, Portugal: Fundação Calouste Glubenkian; 2007
  5. 5. Dixon RA. Natural products and plant disease resistance. Nature. 2005;411:843-847
  6. 6. Ríos J-L. Chapter 1 - Essential oils: What they are and how the terms are used and defined. In: Preedy VR, editor. Essential Oils in Food Preservation, Flavor and Safety. 1st ed. Academic Press; 2016. pp. 3-10
  7. 7. de Morais LAS. Influência dos fatores abióticos na composição química dos óleos essenciais. Horticultura Brasileira. 2009;27(2):S4050-S4S63
  8. 8. Lima HRP, Kaplan MAC, Cruz A. Influência dos fatores abióticos na produção e variabilidade de terpenóides em plantas. Floresta e Ambiente. 2003;10(2):71-77
  9. 9. Figueiredo AC, Barroso JG, Pedro LG, Scheffer JJC. Factors affecting secondary metabolite production in plants: Volatile components and essential oils. Flavour and Fragrance Journal. 2008;23(4):213-226
  10. 10. Dhifi W, Bellili S, Jazi S, Bahloul N, Mnif W. Essential oils’ chemical characterization and investigation of some biological activities: A critical review. Medicines (Basel). 2016;3(4):1-16
  11. 11. Baptiste Hzounda Fokou J, Michel Jazet Dongmo P, Fekam Boyom F. Essential oil’s chemical composition and pharmacological properties. In: El-Shemy HA, editor. Essential Oils: Oils of Nature. IntechOpen; 2020
  12. 12. Turek C, Stintzing FC. Stability of essential oils: A review. Comprehensive Reviews in Food Science and Food Safety. 2013;12(1):40-53
  13. 13. Cragg GM, Newman DJ. Natural products: A continuing source of novel drug leads. Biochimica et Biophysica Acta. 2013;1830(6):3670-3695
  14. 14. Tepe B, Daferera D, Sokmen A, Sokmen M, Polissiou M. Antimicrobial and antioxidant activities of the essential oil and various extracts of Salvia tomentosa Miller (Lamiaceae). Food Chemistry. 2005;90(3):333-340
  15. 15. Yang SM, Feskanich D, Willett WC, Eliassen AH, Wu TY. Association between global biomarkers of oxidative stress and hip fracture in postmenopausal women: A Prospective Study. Journal of Bone and Mineral Research. 2014;29(12):2577-2583
  16. 16. Lykkesfeldt J, Svendsen O. Oxidants and antioxidants in disease: Oxidative stress in farm animals. Veterinary Journal. 2007;173(3):502-511
  17. 17. Nunes XP, Silva FS, JRGdS A, LAdA R, JTd L, LJQ J, et al. Biological oxidations and antioxidant activity of natural products. In: Rao DV, editor. Phytochemicals as Nutraceuticals: Global Approaches to Their Role in Nutrition and Health. Vol. 2012. Brazil: InTech; 2012. p. 278
  18. 18. Paur I, Carlsen MH, Halvorsen BL, Blomhoff R. Antioxidants in herbs and spices: Roles in oxidative stress and redox signaling. In: IFF B, Wachtel-Galor S, editors. Herbal Medicine: Biomolecular and Clinical Aspects. 2nd ed. Boca Raton (FL): CRC Press; 2011
  19. 19. Bakkali F, Averbeck S, Averbeck D, Idaomar M. Biological effects of essential oils: A review. Food and Chemical Toxicology. 2008;46(2):446-475
  20. 20. Brenes A, Roura E. Essential oils in poultry nutrition: Main effects and modes of action. Animal Feed Science and Technology. 2010;158(1-2):1-14
  21. 21. Miguel MG, Matos F, Duarte J, Venancio F, Moiteiro C, Correia AID, et al. Antioxidant capacity of the essential oils from Lavandula luisieri, L. stoechas subsp. lusitanica, L. stoechas subsp. lusitanica x L. luisieri and L. viridis grown in Algarve (Portugal). Journal of Essential Oil Research. 2009;21(4):327-336
  22. 22. Pombal S, Rodrigues CF, Araujo JP, Rocha PM, Rodilla JM, Diez D, et al. Antibacterial and antioxidant activity of Portuguese Lavandula luisieri (Rozeira) Rivas-Martinez and its relation with their chemical composition. Springerplus. 2016;5(1):1711
  23. 23. Arantes S, Candeias F, Lopes O, Lima M, Pereira M, Tinoco T, et al. Pharmacological and toxicological studies of essential oil of Lavandula stoechas subsp. luisieri. Planta Medicine. 2016;82(14):1266-1273
  24. 24. Rufino AT, Ferreira I, Judas F, Salgueiro L, Lopes MC, Cavaleiro C, et al. Differential effects of the essential oils of Lavandula luisieri and Eryngium duriaei subsp. juresianum in cell models of two chronic inflammatory diseases. Pharmaceutical Biology. 2015;53(8):1220-1230
  25. 25. Costa P, Goncalves S, Valentao P, Andrade PB, Almeida C, Nogueira JM, et al. Metabolic profile and biological activities of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco: Studies on the essential oil and polar extracts. Food Chemistry. 2013;141(3):2501-2506
  26. 26. Galego L, Almeida V, Goncalves V, Costa M, Monteiro I, Matos F, Miguel G. Antioxidant activity of the essential oils of Thymbra capitata, Origanum vulgare, Thymus mastichina, and Calamintha baetica. In: Gardner G, Craker LE, editors. XXVII International Horticultural Congress - IHC2006: International Symposium on Plants as Food and Medicine: The Utilization and Development of Horticultural Plants for Human Health Seoul, Korea ISHS Acta Hortic; 2008. pp. 325-334
  27. 27. Arantes SM, Picarra A, Guerreiro M, Salvador C, Candeias F, Caldeira AT, et al. Toxicological and pharmacological properties of essential oils of Calamintha nepeta, Origanum virens and Thymus mastichina of Alentejo (Portugal). Food and Chemical Toxicology. 2019;133:110747
  28. 28. Bozovic M, Ragno R. Calamintha nepeta (L.) Savi and its main essential oil constituent Pulegone: Biological activities and chemistry. Molecules (Basel, Switzerland). 2017;22(2):290-340
  29. 29. Wang W, Wu N, Zu YG, Fu YJ. Antioxidative activity of Rosmarinus officinalis L. essential oil compared to its main components. Food Chemistry. 2008;108(3):1019-1022
  30. 30. Gachkar L, Yadegari D, Rezael MB, Taghizadeh M, Astaneh SA, Rasooli I. Chemical and biological characteristics of Cuminum cyminum and Rosmarinus officinalis essential oils. Food Chemistry. 2007;102(3):898-904
  31. 31. Galovičová L, Borotová P, Valková V, Kačániová M. Antibiofilm and antioxidant activity of Rosmarinus officinalis essential oil. Potravinarstvo Slovak Journal of Food Sciences. 2021;15:1093-1103
  32. 32. Hussain AI, Anwar F, Chatha SA, Jabbar A, Mahboob S, Nigam PS. Rosmarinus officinalis essential oil: Antiproliferative, antioxidant and antibacterial activities. Brazilian Journal of Microbiology : [publication of the Brazilian Society for Microbiology]. 2010;41(4):1070-1078
  33. 33. Erkan N, Ayranci G, Ayranci E. Antioxidant activities of rosemary (Rosmarinus Officinalis L.) extract, blackseed (Nigella sativa L.) essential oil, carnosic acid, rosmarinic acid and sesamol. Food Chemistry. 2008;110(1):76-82
  34. 34. Rašković A, Milanović I, Pavlović N, Ćebović T, Vukmirović S, Mikov M. Antioxidant activity of rosemary (Rosmarinus officinalis L.) essential oil and its hepatoprotective potential. BMC Complementary and Alternative Medicine. 2014;14(1):225
  35. 35. Mata AT, Proenca C, Ferreira AR, Serralheiro MLM, Nogueira JMF, Araujo MEM. Antioxidant and antiacetylcholinesterase activities of five plants used as Portuguese food spices. Food Chemistry. 2007;103(3):778-786
  36. 36. Cutillas AB, Carrasco A, Martinez-Gutierrez R, Tomas V, Tudela J. Thymus mastichina L. essential oils from Murcia (Spain): Composition and antioxidant, antienzymatic and antimicrobial bioactivities. PLoS One. 2018;13(1):e0190790
  37. 37. Cavanagh HM, Wilkinson JM. Biological activities of lavender essential oil. Phytotherapy Research : PTR. 2002;16(4):301-308
  38. 38. Hajhashemi V, Ghannadi A, Sharif B. Anti-inflammatory and analgesic properties of the leaf extracts and essential oil of Lavandula angustifolia Mill. Journal of Ethnopharmacology. 2003;89(1):67-71
  39. 39. Upson T, Andrews S. The taxonomy of the genus Lavandula L. In: Lis-Balchin M, editor. Lavander, the Genus Lavandula, Medicinal and Aromatic Plants- Pndustrial profiles. Londres and Nova Iorque: Taylor and Francis; 2002. p. 2
  40. 40. Castroviejo S, Iberica F. Plantas vasculares de la Península Ibérica e Islas Baleares. Madrid: Real Jardín Botánico, CSIC; 2010
  41. 41. Franco JA. Nova Flora de Portugal (Continente e Açores). Portugal: Lisboa Editora; 1984
  42. 42. Zuzarte MR, Dinis AM, Cavaleiro C, Salgueiro LR, Canhoto JM. Trichomes, essential oils and in vitro propagation of Lavandula pedunculata (Lamiaceae). Industrial Crops and Products. 2010;32(3):580-587
  43. 43. Nogueira JM, Romano A. Essential oils from micropropagated plants of Lavandula viridis. Phytochemical Analysis. 2002;13(1):4-7
  44. 44. Goncalves S, Serra H, Nogueira JMF, Almeida R, Custodio L, Romano A. Headspace-SPME of in vitro shoot-cultures and micropropagated plants of Lavandula viridis. Biologia Plantarum. 2008;52(1):133-136
  45. 45. Zuzarte M, Goncalves MJ, Cavaleiro C, Canhoto J, Vale-Silva L, Silva MJ, et al. Chemical composition and antifungal activity of the essential oils of Lavandula viridis L'Her. Journal of Medical Microbiology. 2011;60(Pt 5):612-618
  46. 46. Costa P, Grosso C, Gonçalves S, Andrade PB, Valentão P, Bernardo-Gil MG, et al. Supercritical fluid extraction and hydrodistillation for the recovery of bioactive compounds from Lavandula viridis L’Hér. Food Chemistry. 2012;135:112-121
  47. 47. Ćavar S, Vidic D, Maksimović M. Volatile constituents, phenolic compounds, and antioxidant activity of Calamintha glandulosa (Req.) Bentham. Journal of the Science of Food and Agriculture. 2013;93(7):1758-1764
  48. 48. Negro C, Notarnicola S, De Bellis L, Miceli A. Intraspecific variability of the essential oil of Calamintha nepeta subsp. nepeta from Southern Italy (Apulia). Natural Product Research. 2013;27(4-5):331-339
  49. 49. Hammer K, Laghetti G, Pistrick K. Calamintha nepeta (L.) Savi and Micromeria thymifolia (Scop.) Fritsch cultivated in Italy. Genetic Resources and Crop Evolution. 2005;52(2):215-219
  50. 50. Marongiu B, Piras A, Porcedda S, Falconieri D, Maxia A, Goncalves MJ, et al. Chemical composition and biological assays of essential oils of Calamintha nepeta (L.) Savi subsp. nepeta (Lamiaceae). Natural Product Research. 2010;24(18):1734-1742
  51. 51. Araniti F, Lupini A, Sorgona A, Statti GA, Abenavoli MR. Phytotoxic activity of foliar volatiles and essential oils of Calamintha nepeta (L.) Savi. Natural Product Research. 2013;27(18):1651-1656
  52. 52. Araniti F, Grana E, Reigosa MJ, Sanchez-Moreiras AM, Abenavoli MR. Individual and joint activity of terpenoids, isolated from Calamintha nepeta extract, on Arabidopsis thaliana. Natural Product Research. 2013;27(24):2297-2303
  53. 53. Formisano C, Oliviero F, Rigano D, Saab AM, Senatore F. Chemical composition of essential oils and in vitro antioxidant properties of extracts and essential oils of Calamintha origanifolia and Micromeria myrtifolia, two Lamiaceae from the Lebanon flora. Industrial Crops and Products. 2014;62:405-411
  54. 54. Pacifico S, Galasso S, Piccolella S, Kretschmer N, Pan S-P, Marciano S, et al. Seasonal variation in phenolic composition and antioxidant and anti-inflammatory activities of Calamintha nepeta (L.) Savi. Foodservice Research International. 2015;69(1):121-132
  55. 55. Hernández MD, Sotomayor JA, Hernández Á, Jordán MJ. Rosemary (Rosmarinus officinalis L.) Oils. In: Preedy VR, editor. Essential Oils in Food Preservation, Flavor and Safety. San Diego: Academic Press; 2016. pp. 677-688
  56. 56. Alu’datt MH, Rababah T, Alhamad MN, Gammoh S, Al-Mahasneh MA, Tranchant CC, et al. Chapter 15 - Pharmaceutical, nutraceutical and therapeutic properties of selected wild medicinal plants: Thyme, spearmint, and rosemary. In: Grumezescu AM, Holban AM, editors. Therapeutic, Probiotic, and Unconventional Foods. Academic Press; 2018. pp. 275-290
  57. 57. Cunha AP, Ribeiro JA, Roque OR. Plantas aromáticas em portugal Caracterização e Utilização. Lisboa, Portugal: Fundação Calouste Gulbenkian; 2007
  58. 58. Ribeiro BS, Ferreira MdF, Moreira JL, Santos L. Simultaneous distillation–Extraction of essential oils from Rosmarinus officinalis L. Cosmetics. 2021;8(4):117-127
  59. 59. Jordan MJ, Lax V, Rota MC, Loran S, Sotomayor JA. Effect of bioclimatic area on the essential oil composition and antibacterial activity of Rosmarinus officinalis L. Food Control. 2013;30(2):463-468
  60. 60. Martins MR, Tinoco MT, Almeida AS, Cruz-Morais J. Chemical composition, antioxidant and antimicrobial properties of three essential oils from Portuguese flora. Journal of Phcog. 2012;3(1):39-44
  61. 61. Tohidi B, Rahimmalek M, Trindade H. Review on essential oil, extracts composition, molecular and phytochemical properties of Thymus species in Iran. Industrial Crops and Products. 2019;134:89-99
  62. 62. Stahl-Biskup E, Laakso I. Essential oil polymorphism in finnish thymus species. Planta Medica. 1990;56(5):464-468
  63. 63. Sostaric I, Arsenijevic J, Acic S, Stevanovic ZD. Essential oil polymorphism of Thymus pannonicus All. (Lamiaceae) in Serbia. Journal of Essential Oil-Bearing Plants. 2012;15(2):237-243
  64. 64. Salgueiro LR, Vila R, Felix T, Figueiredo AC, Barroso JG, Canigueral S, et al. Variability of essential oils of Thymus caespititius from Portugal. Phytochemistry. 1997;45(2):307-311
  65. 65. Salgueiro LR, Vila R, Tomas X, Canigueral S, Paiva J, Proenca da Cunha A, et al. Chemotaxonomic study on Thymus villosus from Portugal. Biochemical Systematics and Ecology. 2000;28(5):471-482
  66. 66. Salgueiro LMR. Essential oils of endemic Thymus species from Portugal. Flavour and Fragrance Journal. 1992;7(3):159-162
  67. 67. Li X, He T, Wang X, Shen M, Yan X, Fan S, et al. Traditional uses, chemical constituents and biological activities of plants from the Genus Thymus. Chemistry & Biodiversity. 2019;16(9):e1900254
  68. 68. FLORA-ON. Flora de Portugal Interativa. Sociedade Portuguesa de Botânica [Available from: http://www.flora-on.pt
  69. 69. Mendez-Tovar I, Martin H, Santiago Y, Ibeas A, Herrero B, Asensio-S-Manzanera MC. Variation in morphological traits among Thymus mastichina (L.) L. populations. Genetic Resources and Crop Evolution. 2015;62(8):1257-1267
  70. 70. Salgueiro LR, Pinto E, Gonçalves MJ, Costa I, Palmeira A, Cavaleiro C, et al. Antifungal activity of the essential oil of Thymus capitellatus against Candida, Aspergillus and dermatophyte strains. Flavour and Fragrance Journal. 2006;21(5):749-753
  71. 71. Benchaar C, Calsamiglia S, Chaves AV, Fraser GR, Colombatto D, McAllister TA, et al. A review of plant-derived essential oils in ruminant nutrition and production. Animal Feed Science and Technology. 2008;145(1-4):209-228
  72. 72. Chiang HM, Chiu HH, Lai YM, Chen CY, Chiang HL. Carbonyl species characteristics during the evaporation of essential oils. Atmospheric Environment. 2010;44(18):2240-2247
  73. 73. Jori A, Bianchetti A, Prestini PE, Gerattini S. Effect of eucalyptol (1,8-cineole) on the metabolism of other drugs in rats and in man. European Journal of Pharmacology. 1970;9(3):362-366
  74. 74. Moss M, Oliver L. Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma. Therapeutics Advances in Psychopharmacology. 2012;2(3):103-113
  75. 75. Murata S, Shiragami R, Kosugi C, Tezuka T, Yamazaki M, Hirano A, et al. Antitumor effect of 1, 8-cineole against colon cancer. Oncology Reports. 2013;30(6):2647-2652
  76. 76. Juergens UR. Anti-inflammatory properties of the monoterpene 1.8-cineole: Current evidence for co-medication in inflammatory airway diseases. Drug Research (Stuttg). 2014;64(12):638-646
  77. 77. Brown SK, Garver WS, Orlando RA. 1,8-cineole: An underappreciated anti-inflammatory therapeutic. Journal of Biomolecular Research & Therapeutics. 2017;06(01):154-160
  78. 78. Vuuren SFV, Viljoen AM. Antimicrobial activity of limonene enantiomers and 1, 8-cineole alone and in combination. Flavour and Fragrance Journal. 2007;22(6):540-544
  79. 79. Santos FA, Rao VS. 1,8-cineol, a food flavoring agent, prevents ethanol-induced gastric injury in rats. Digestive Diseases and Sciences. 2001;46(2):331-337
  80. 80. Khan A, Vaibhav K, Javed H, Tabassum R, Ahmed ME, Khan MM, et al. 1,8-cineole (eucalyptol) mitigates inflammation in amyloid Beta toxicated PC12 cells: Relevance to Alzheimer's disease. Neurochemical Research. 2014;39(2):344-352
  81. 81. Cai ZM, Peng JQ, Chen Y, Tao L, Zhang YY, Fu LY, et al. 1,8-Cineole: A review of source, biological activities, and application. Journal of Asian Natural Products Research. 2021;23(10):938-954
  82. 82. Bhowal M, Gopal M. Eucalyptol: Safety and pharmacological profile. Journal of Pharmaceutical Sciences. 2015;5:125-131
  83. 83. Zuzarte M, Goncalves MJ, Cruz MT, Cavaleiro C, Canhoto J, Vaz S, et al. Lavandula luisieri essential oil as a source of antifungal drugs. Food Chemistry. 2012;135(3):1505-1510
  84. 84. Gonzalez-Coloma A, Martin-Benito D, Mohamed N, Garcia-Vallejo MC, Soria AC. Antifeedant effects and chemical composition of essential oils from different populations of Lavandula luisieri L. Biochemical Systematics and Ecology. 2006;34(8):609-616
  85. 85. Baldovini N, Lavoine-Hanneguelle S, Ferrando G, Dusart G, Lizzani-Cuvelier L. Necrodane monoterpenoids from Lavandula luisieri. Phytochemistry. 2005;66(14):1651-1655
  86. 86. Sanz J, Soria AC, Garcia-Vallejob MC. Analysis of volatile components of Lavandula luisieri L. by direct thermal desorption-gas chromatography-mass spectrometry. Journal of Chromatography. A. 2004;1024(1-2):139-146
  87. 87. Lavoine-Hanneguelle S, Casabianca H. New compounds from the essential oil and absolute of Lavandula luisieri L. Journal of Essential Oil Research. 2004;16(5):445-448
  88. 88. Zuzarte M, Sousa C, Cavaleiro C, Cruz MT, Salgueiro L. The Anti-Inflammatory Response of Lavandula luisieri and Lavandula pedunculata Essential Oils. Plants. 2022;11(3):370-376
  89. 89. Feijao MD, Teixeira G, Vasconcelos T, Rodrigues L, Correia AI, Sanches J, et al. Essential oil variability and trichomes morphology from Lavandula pedunculata (Mill.) Cav. grown at Mata Experimental do Escaroupim (Portugal). Planta Medica. 2011;77(12):1297
  90. 90. Zuzarte M, Goncalves MJ, Cavaleiro C, Dinis AM, Canhoto JM, Salgueiro LR. Chemical composition and antifungal activity of the essential oils of Lavandula pedunculata (Miller) Cav. Chemistry & Biodiversity. 2009;6(8):1283-1292
  91. 91. Boukhobza Z, Boulenouar N, AbdelkrİM C, Kadrİ Z. Essential Oil of Rosmarinus officinalis L. from West Highlands of Algeria: Chemical Composition and Antifungal Activity against Fusarium oxysporum f. sp. albedinis. Natural Volatiles and Essential Oils. 2021;8(3):44-45
  92. 92. Ambrico A, Trupo M, Martino M, Sharma N. Essential oil of Calamintha nepeta (L.) Savi subsp. nepeta is a potential control agent for some postharvest fruit diseases. Organic. Agriculture. 2019;10(1):35-48
  93. 93. Kitic D, Stojanovic G, Palic R, Randjelovic V. Chemical composition and microbial activity of the essential oil of Calamintha nepeta (L.) Savi ssp nepeta var. subisodonda (Borb.) Hayek from Serbia. Journal of Essential Oil Research. 2005;17(6):701-703
  94. 94. Miguel MG, Duarte F, Venancio F, Tavares R. Chemical composition of the essential oils from Thymus mastichina over a day period. Proceedings of the International Conference on Medicinal and Aromatic Plants Possibilities and Limitations of Medicinal and Aromatic Plant Production in the 21st Century. 2002;576:87-90
  95. 95. Fraternale D, Giamperi L, Ricci D, Rocchi MBL, Guidi L, Epifano F, et al. The effect of triacontanol on micropropagation and on secretory system of Thymus mastichina. Plant Cell, Tissue and Organ Culture. 2003;74(1):87-97
  96. 96. Machado M, Dinis AM, Santos-Rosa M, Alves V, Salgueiro L, Cavaleiro C, et al. Activity of Thymus capitellatus volatile extract, 1,8-cineole and borneol against Leishmania species. Veterinary Parasitology. 2014;200(1-2):39-49
  97. 97. Delgado F. Conservação e valorização de Asphodelus bento-rainhae P.Silva e Lavandula luisieri (Rozeira) Rivas -Martínez da Beira Interior. Lisboa, Portugal: Universidade Técnica de Lisboa; 2010
  98. 98. Garcia-Vallejo MI, Garcia-Vallejo MC, Sanz J, Bernas M, Velasco– Negueruela A. Necrodane (1,2,2,3,4-pentamethylcyclopentana) derivaties in Lavandula luisieri, new compounds to the plant kingdom. Phytochemistry. 1994;36:43-45
  99. 99. Negueruela AV, Perez-Alonso MJ, Maria J, Rico MM. Essential oil of Iberian Lamiaceae with pulegone as basic component. Anales de Bromatologia. 1987;39:357-372
  100. 100. Akgül A, Pooter HL, Buyck LF. The essential oils of Calamintha nepeta subsp. nepeta and ssp. glandulosa and Ziziphora clinopodioides from Turkey. Journal of Essential Oil Research. 1991;3:7-10
  101. 101. Risstorcelli D, Tomi F, Casanova J. Essential oils of Calamintha nepeta subsp. nepeta and subsp. glandulosa from Corsica (France). Journal of Essential Oil Research. 1996;8:363-366
  102. 102. Flamini G, Cioni PL, Puleio R, Morelli I, Panizzi L. Antimicrobial activity of the essential oil of Calamintha nepetaand its constituent pulegone against bacteria and fungi. Phytotherapy Research: PTR. 1999;13(4):349-351
  103. 103. Cozzolino F, Fellous R, Vernin G, Parkanyi C. GC/MS Analysis of the Volatile Constituents of Calamintha nepeta (L.) Savi ssp. nepeta from Southeastern France. Journal of Essential Oil Research. 2000;12(4):481-486
  104. 104. Couladis M, Tzakou O. Essential oil of Calamintha nepeta subsp glandulosa from Greece. Journal of Essential Oil Research. 2001;13(1):11-12
  105. 105. Kitic D, Jovanovic T, Ristic M, Palic R, Stojanovic G. Chemical composition and antimicrobial activity of the essential oil of Calamintha nepeta (L.) Savi ssp. glandulosa (Req.) P.W. Ball from Montenegro. Journal of Essential Oil Research. 2002;14(2):150-152
  106. 106. Fraternale D, Giamperi L, Ricci D, Manunta A. Composition of the essential oil as a taxonomic marker for Calamintha nepeta (L.) Savi ssp. nepeta. Journal of Essential Oil Research. 1998;10:568-570
  107. 107. Arantes SM, Picarra A, Guerreiro M, Salvador C, Candeias F, Caldeira AT, Martins MR. Toxicological and pharmacological properties of essential oils of Calamintha nepeta, Origanum virens and Thymus mastichina of Alentejo (Portugal). Food and Chemical Toxicology. 2019;133:110747-110755
  108. 108. Arantes S, Picarra A, Candeias F, Caldeira AT, Martins MR, Teixeira D. Antioxidant activity and cholinesterase inhibition studies of four flavouring herbs from Alentejo. Natural Product Research. 2017;31(18):2183-2187
  109. 109. Macedo-Arantes S, Picarra A, Caldeira AT, Candeias AE, Martins MR. Essential oils of Portuguese flavouring plants: Potential as green biocides in cultural heritage. European Physical Journal Plus. 2021;136(11):1-15
  110. 110. Galovičová L, Borotová P, Valková V, Vukovic NL, Vukic M, Štefániková J, et al. Thymus vulgaris essential oil and its biological activity. Plants (Basel, Switzerland). 2021;10(9):1959-1976
  111. 111. Salgueiro LR, Vila R, Tomas X, Canigueral S, DaCunha AP, Adzet T. Composition and variability of the essential oils of Thymus species from Section Mastichina from Portugal. Biochemical Systematics and Ecology. 1997;25(7):659-672
  112. 112. Moldão-Martins M, Beirão-da-Costa S, Neves C, Cavaleiro C, Lg S. Luı́sa Beirão-da-Costa M. Olive oil flavoured by the essential oils of Mentha × piperita and Thymus mastichina L. Food Quality and Preference. 2004;15(5):447-452
  113. 113. Chiu HH, Chiang HM, Lo CC, Cheri CY, Chiang HL. Constituents of volatile organic compounds of evaporating essential oil. Atmospheric Environment. 2009;43(36):5743-5749
  114. 114. Ghasemzadeh A, Ghasemzadeh N. Flavonoids and phenolic acids: Role and biochemical activity in plants and human. Journal of Medicinal Plant Research. 2011;5(31):6697-6703
  115. 115. Pelicano H, Carney D, Huang P. ROS stress in cancer cells and therapeutic implications. Drug Resistance Updates. 2004;7(2):97-110
  116. 116. Moyo M, Ndhlala AR, Finnie JF, Van Staden J. Phenolic composition, antioxidant and acetylcholinesterase inhibitory activities of Sclerocarya birrea and Harpephyllum caffrum (Anacardiaceae) extracts. Food Chemistry. 2010;123(1):69-76
  117. 117. Albano SM, Miguel MG. Biological activities of extracts of plants grown in Portugal. Industrial Crops and Products. 2011;33(2):338-343
  118. 118. Gonzalez-Coloma A, Delgado F, Rodilla JM, Silva L, Sanz J, Burillo J. Chemical and biological profiles of Lavandula luisieri essential oils from western Iberia Peninsula populations. Biochemical Systematics and Ecology. 2011;39(1):1-8
  119. 119. Miguel MG, Falcato-Simoes M, Figueiredo AC, Barroso JMG, Pedro LG, Carvalho LM. Evaluation of the antioxidant activity of Thymbra capitata, Thymus mastichina and Thymus camphoratus essential oils. Journal of Food Lipids. 2005;12(3):181-197
  120. 120. Smeriglio A, Alloisio S, Raimondo FM, Denaro M, Xiao J, Cornara L, et al. Essential oil of Citrus lumia Risso: Phytochemical profile, antioxidant properties and activity on the central nervous system. Food and Chemical Toxicology. 2018;119:407-416
  121. 121. Ruberto G, Baratta MT. Antioxidant activity of selected essential oil components in two lipid model systems. Food Chemistry. 2000;69(2):167-174
  122. 122. Shahat AA, Ibrahim AY, Hendawy SF, Omer EA, Hammouda FM, Abdel-Rahman FH, et al. Chemical composition, antimicrobial and antioxidant activities of essential oils from organically cultivated fennel cultivars. Molecules (Basel, Switzerland). 2011;16(2):1366-1377
  123. 123. Lobo AP, García YD, Sánchez JM, Madrera RR, Valles BS. Phenolic and antioxidant composition of cider. Journal of Food Composition and Analysis. 2009;22:644-648
  124. 124. Podsedek A. Natural antioxidants and antioxidant capacity of Brassica vegetables: A review. LWT- Food Science and Technology. 2007;40(1):1-11
  125. 125. Raut JS, Karuppayil SM. A status review on the medicinal properties of essential oils. Industrial Crops and Products. 2014;62:250-264
  126. 126. Miguel MG. Antioxidant and anti-inflammatory activities of essential oils: A short review. Molecules (Basel, Switzerland). 2010;15(12):9252-9287
  127. 127. Dohi S, Terasaki M, Makino M. Acetylcholinesterase inhibitory activity and chemical composition of commercial essential oils. Journal of Agricultural and Food Chemistry. 2009;57(10):4313-4318
  128. 128. Li CJ, Chang JK, Wang GJ, Ho ML. Constitutively expressed COX-2 in osteoblasts positively regulates Akt signal transduction via suppression of PTEN activity. Bone. 2011;48(2):286-297
  129. 129. Utar Z, Majid MI, Adenan MI, Jamil MF, Lan TM. Mitragynine inhibits the COX-2 mRNA expression and prostaglandin E(2) production induced by lipopolysaccharide in RAW264.7 macrophage cells. Journal of Ethnopharmacology. 2011;136(1):75-82
  130. 130. Calvello R, Panaro MA, Carbone ML, Cianciulli A, Perrone MG, Vitale P, et al. Novel selective COX-1 inhibitors suppress neuroinflammatory mediators in LPS-stimulated N13 microglial cells. Pharmacological Research. 2012;65(1):137-148
  131. 131. Jeon J, Park KA, Lee H, Shin S, Zhang T, Won M, et al. Water extract of Cynanchi atrati Radix regulates inflammation and apoptotic cell death through suppression of IKK-mediated NF-kB signaling. Journal of Ethnopharmacology. 2011;137:626-634
  132. 132. Rios JL. Effects of triterpenes on the immune system. Journal of Ethnopharmacology. 2010;128(1):1-14
  133. 133. Kumar N, Drabu S, Mondal SC. NSAID’s and selectively COX-2 inhibitors as potential chemoprotective agents against cancer. Arabian Journal of Chemistry. 2013;6(1):1-23
  134. 134. Suresh V, Sruthi V, Padmaja B, Asha VV. In vitro anti-inflammatory and anti-cancer activities of Cuscuta reflexa Roxb. Journal of Ethnopharmacology. 2011;134(3):872-877
  135. 135. Homnan N, Thongpraditchote S, Chomnawang M, Thirapanmethee K. In vitro Anti-inflammatory effects of Thai herb essential oils. Asiaweek. 2020;47(2):153-163
  136. 136. Valacchi G, Virgili F, Cervellati C, Pecorelli A. OxInflammation: From subclinical condition to pathological biomarker. Frontiers in Physiology. 2018;9:858
  137. 137. Rohleder N. Stress and inflammation: The need to address the gap in the transition between acute and chronic stress effects. Psychoneuroendocrinology. 2019;105:164-171
  138. 138. Monti D, Ostan R, Borelli V, Castellani G, Franceschi C. Inflammaging and human longevity in the omics era. Mechanisms of Ageing and Development. 2017;165(Pt B):129-138
  139. 139. Franceschi C, Campisi J. Chronic inflammation (inflammaging) and its potential contribution to age-associated diseases. The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences. 2014;69(Suppl 1):S4-S9
  140. 140. Fulop T, Witkowski JM, Olivieri F, Larbi A. The integration of inflammaging in age-related diseases. Seminars in Immunology. 2018;40:17-35
  141. 141. Baylis D, Bartlett DB, Patel HP, Roberts HC. Understanding how we age: Insights into inflammaging. Longevity & Healthspan. 2013;2(8):1-8
  142. 142. de Lavor EM, Fernandes AWC, de Andrade Teles RB, Leal A, de Oliveira Junior RG, Gama ESM, et al. Essential oils and their major compounds in the treatment of chronic inflammation: A review of antioxidant potential in preclinical studies and molecular mechanisms. Oxidative Medicine and Cellular Longevity. 2018;2018:6468593
  143. 143. de Sousa DP. Analgesic-like activity of essential oils constituents. Molecules (Basel, Switzerland). 2011;16(3):2233-2252
  144. 144. Schabauer L, Steflitsch W, Buchbauer G. Essential oils and compounds against pains in animal studies. Natural Product Communications. 2017;12(7):1137-1143
  145. 145. Sarmento-Neto JF, do Nascimento LG, Felipe CF, de Sousa DP. Analgesic potential of essential oils. Molecules (Basel, Switzerland). 2015;21(1):E20
  146. 146. da Silveira ESR, Lima TC, Nobrega FR, Brito AEM, Sousa DP. Analgesic-like activity of essential oil constituents: An update. International Journal of Molecular Sciences. 2017;18(12):1-40
  147. 147. Lenardão EJ, Savegnago L, Jacob RG, Victoria FN, Martinez DM. Antinociceptive effect of essential oils and their constituents: An update review. Journal of the Brazilian Chemical Society. 2015;27(3):435-474
  148. 148. Santos FA, Rao VS. Antiinflammatory and antinociceptive effects of 1,8-cineole a terpenoid oxide present in many plant essential oils. Phytotherapy Research : PTR. 2000;14(4):240-244
  149. 149. Peana AT, D'Aquila PS, Panin F, Serra G, Pippia P, Moretti MD. Anti-inflammatory activity of linalool and linalyl acetate constituents of essential oils. Phytomedicine. 2002;9(8):721-726
  150. 150. Miller SG, Pritts TA. Linalool: A novel natural anti-inflammatory agent?: Commentary on "Anti-inflammatory effects of linalool in RAW 264.7 macrophages and lipopolysaccharide-induced lung injury model". The Journal of Surgical Research. 2013;185(1):e69-e70
  151. 151. da Silveira R, Andrade LN, de Sousa DP. A review on anti-inflammatory activity of monoterpenes. Molecules (Basel, Switzerland). 2013;18(1):1227-1254
  152. 152. Guimaraes AG, Quintans JS, Quintans LJ Jr. Monoterpenes with analgesic activity: A systematic review. Phytotherapy Research : PTR. 2013;27(1):1-15
  153. 153. Loizzo MR, Tundis R, Menichini F, Saab AM, Statti GA, Menichini F. Cytotoxic activity of essential oils from Labiatae and Lauraceae families against in vitro human tumor models. Anticancer Research. 2007;27(5A):3293-3299
  154. 154. Dragomanova S, Tancheva L, Georgieva M, Klisurov R. Analgesic and anti-inflammatory activity of monoterpenoid myrtenal in rodents. Journal of Imab. 2019;25(1):2406-2413
  155. 155. Pergolizzi JV, Taylor R, JA LQ, Raffa RB, Group NR. The role and mechanism of action of menthol in topical analgesic products. Journal of Clinical Pharmacy and Therapeutics. 2018;43(3):313-319
  156. 156. Sengupta R, Sheorey SD, Hinge M. Analgesic and anti-inflammatory plants: An updated review. International Journal of Pharmaceutical Sciences Review and Research. 2012;12:114-119
  157. 157. Padhan DK. Topical analgesic activity of essential oil extracted from Spharenthus Indicus (Asteraceae). Asian Journal of Pharmaceutical and Clinical Research. 2017;10(5):275-277
  158. 158. Cardia GFE, Silva-Filho SE, Silva EL, Uchida NS, Cavalcante HAO, Cassarotti LL, et al. Effect of Lavender (Lavandula angustifolia) essential oil on acute inflammatory response. Evidence-based Complementary and Alternative Medicine. 2018;2018:1413940
  159. 159. Juhas S, BujnaKova D, Rehak P, Cikos S, Czikkova S, Vesela J, et al. Anti-inflammatory effects of thyme essential oil in mice. Acta Veterinaria Brno. 2008;77(3):327-334
  160. 160. Fachini-Queiroz FC, Kummer R, Estevao-Silva CF, Carvalho MD, Cunha JM, Grespan R, et al. Effects of thymol and carvacrol, constituents of Thymus vulgaris L. essential oil, on the inflammatory response. Evidence-based Complementary and Alternative Medicine. 2012;2012:657026
  161. 161. Goncalves JC, de Meneses DA, de Vasconcelos AP, Piauilino CA, Almeida FR, Napoli EM, et al. Essential oil composition and antinociceptive activity of Thymus capitatus. Pharmaceutical Biology. 2017;55(1):782-786
  162. 162. Juergens LJ, Worth H, Juergens UR. New perspectives for mucolytic, anti-inflammatory and adjunctive therapy with 1,8-cineole in COPD and asthma: Review on the new therapeutic approach. Advances in Therapy. 2020;37(5):1737-1753

Written By

Sílvia Macedo Arantes, Ana Teresa Caldeira and Maria Rosário Martins

Submitted: 11 February 2022 Reviewed: 21 February 2022 Published: 02 June 2022