Antioxidant Capacity of the Essential Oils FromLavandula luisieri, L. stoechas subsp. lusitanica, L. stoechassubsp.lusitanicaxL. luisieriandL. viridisGrown in Algarve (Portugal)

In Vitro Propagation and Conservation of Lavandula stoechas subsp. luisieri and Pterospartum tridentatum, Two Important Medicinal and Aromatic Species from Portugal

Lavandula stoechas subsp. luisieri and Pterospartum tridentatum are two valuable aromatic and medicinal plants. Their biometric and morphological parameters, such as the number of new shoots, length of the longest shoot, multiplication rate, and fresh weight, were evaluated using the multiplication MS medium protocol. The rooting protocols involved immersing the explants in IBA (1 g L-1) and a commercial IBA (3.3 g L-1) preparation (Clonex®). Slow-growth conservation assays were carried out using two different sucrose concentrations (15 g L-1 and 30 g L-1), and a control, with the cultures kept at 4 °C for 12 months. The multiplication rate for L. stoechas subsp. luisieri was 6.8, and that of P. tridentatum was 13.3, achieved using the MS medium supplemented with 0.2 mg L-1 BAP, 1 mg L-1 BAP, and 0.5 mg L-1 IBA. The application of Clonex® showed the best ex vitro rooting results in L. stoechas subsp. luisieri (77%) and P. tridentatum (90%). In the slow-growth conservation assays, at 4 °C, in darkness for 12 months, an excellent survival rate was achieved in L. stoechas subsp. luisieri (>80%) and P. tridentatum (>90%), even at the reduced sucrose concentration. This study demonstrates the effectiveness of in vitro multiplication and ex vitro rooting protocols for two valuable aromatic and medicinal plants. These findings are significant for the ex situ conservation of these species, as they provide effective long-term preservation and utilization strategies.

Mediterranean Lavenders from Section Stoechas: An Undervalued Source of Secondary Metabolites with Pharmacological Potential

Globally, climate change and wildfires are disrupting natural ecosystems, thus setting several endemic species at risk. The genus Lavandula is widely present in the Mediterranean region and its species, namely, those included in the section Stoechas, are valuable resources of active compounds with several biological assets. Since ancient times lavenders have been used in traditional medicine and for domestic purposes. These species are melliferous, decorative, and essential oil-producing plants with a high economic interest in the pharmaceutical, flavor, fragrance, and food industries. The essential oils of Lavandula section Stoechas are characterized by high amounts of 1,8-cineole, camphor, fenchone, and specifically for L. stoechas subsp. luisieri one of the major compounds is trans-α-necrodyl acetate. On the other hand, the diversity of non-volatile components like phenolic compounds, such as phenolic acids and flavonoids, make these species an important source of phytochemicals with pharmacological interest. Rosmarinic, caffeic, and salvianolic B acids are the major phenolic acids, and luteolin and eriodictyol-O-glucuronide are the main reported flavonoids. However, the concentration of these secondary metabolites is strongly affected by the plant’s phenological phase and varies in Lavandula sp. from different areas of origin. Indeed, lavender extracts have shown promising antioxidant, antimicrobial, anti-inflammatory, and anticancer properties as well as several other beneficial actions with potential for commercial applications. Despite several studies on the bioactive potential of lavenders from the section Stoechas, a systematized and updated review of their chemical profile is lacking. Therefore, we carried out the present review that gathers relevant information on the different types of secondary metabolites found in these species as well as their bioactive potential.

Chemical Characterization of Three Artemisia tridentata Essential Oils and Multivariate Analyses: A Preliminary Investigation

Background/Objective: Big sagebrush ( Artemisia tridentata Nutt., Asteraceae) is a conspicuous shrub growing in arid and semi-arid regions of intermountain western North America, from eastern Washington and Oregon, through Nevada, Idaho, and Utah, into northern Arizona and New Mexico, and east as far as the western Dakotas, and Colorado. At least three subspecies of A. tridentata have been recognized, including A. tridentata subsp. tridentata Nutt. (basin big sagebrush), A. tridentata subsp. wyomingensis Beetle & A.L.Young (Wyoming big sagebrush), and A. tridentata subsp. vaseyana (Rydb.) Beetle (mountain big sagebrush). Although big sagebrush is an important food source and cover for several animal species, the volatile phytochemistry has shown wide variation in composition. The purpose of this work was to compare and contrast the essential oil compositions of the three subspecies of A. tridentata growing in southwestern Idaho. Methods/Results: Several samples of A. tridentata subsp. wyomingensis and A. tridentata subsp. vaseyana were collected, the essential oils obtained by hydrodistillation using a Likens-Nickerson apparatus in yields of 2.33%-4.45% and 0.90%-1.73%, respectively, and the essential oils analyzed by gas chromatographic techniques. Although A. tridentata shows wide variation in essential oil compositions, multivariate analysis (hierarchical cluster analysis and principal component analysis) indicated A. tridentata subsp. tridentata to be characterized by high concentrations of yomogi alcohol (5.8%-30.8%) and camphor (5.2%-20.1%), while camphor was the defining component in A. tridentata subsp. wyomingensis (10.0%-30.1%) and subsp. vaseyana (16.1%-40.2%). One sample of A. tridentata subsp. vaseyana was dominated by α-thujone (76.1%), however. Conclusion: There is much variation in essential oil compositions of A. tridentata, both within subspecies and between geographical locations; much additional investigation is necessary to more fully characterize the volatile phytochemistry of this plant.

Lavandula viridis L´Hér. Essential Oil Inhibits the Inflammatory Response in Macrophages Through Blockade of NF-KB Signaling Cascade

Lavandulaviridis L´Hér. is an endemic Iberian species with a high essential oil yield and a pleasant lemon scent. Despite these interesting features, this species remains unrecognized and poorly explored by the food and pharmaceutical industries. Nevertheless, it has been valued in traditional medicine being used against flu, circulatory problems and to relieve headaches. Since these disorders trigger inflammatory responses, it is relevant to determine the anti-inflammatory potential of L. viridis L´Hér. essential oil in an attempt to validate its traditional use and concomitantly to increment its industrial exploitation. Therefore, in the present study the chemical composition of this volatile extract as well as the effect on ROS production, inflammatory response and proteasome activity on LPS-stimulated macrophages were disclosed. Also, its safety profile on keratinocytes, hepatocytes and alveolar epithelial cells was depicted, envisioning a future human administration. The essential oil was characterized by high quantities of 1,8-cineole, camphor and α-pinene. From a pharmacological point of view, the essential oil showed a potent antioxidant effect and inhibited nitric oxide production through down-modulation of nuclear factor kappa B-dependent Nos2 transcription and consequently iNOS protein expression as well as a decrease in proteasomal activity. The anti-inflammatory activity was also evidenced by a strong inhibition of LPS-induced Il1b and Il6 transcriptions and downregulation of COX-2 levels. Overall, bioactive safe concentrations of L. viridis L´Hér. essential oil were disclosed, thus corroborating the traditional usage of this species and paving the way for the development of plant-based therapies.

Essential oils of spontaneous species of the genus Lavandula from Portugal: a brief review

Spontaneous lavender growing in uncultivated fields in Portugal have been used in traditional medicine for internal and external uses. The essential oils (EOs) of Lavandula stoechas subsp. luisieri are characterized by the presence of trans-α-necrodyl acetate and trans-necrodol. These EOs are able to prevent the generation and deposition of neurotoxic β-amyloid peptide in Alzheimer's disease. The EOs also present antibacterial, anti-fungal, anti-Leishmania, antioxidant, anti-inflammatory and antifeedant effects. In the case of hydrodistillation, the predominant compound of Lavandula viridis EO was 1,8-cineole, nevertheless in the case of supercritical fluid extraction, the main constituent was camphor. In in vitro shoots EOs, 1,8-cineole and α-pinene were the most important compounds. The EOs presented anti-fungal activity particularly against Cryptococcus neoformans and dermatophytes. The antioxidant and anti-protozoal activities of L. viridis EOs were lower than L. stoechas subsp. luisieri EOs, with hydrodistillation being the best method for obtaining samples with higher antioxidant and anti-acetylcholinesterase activities. The presence of fenchone, 1,8-cineole and camphor was a common trace of the Lavandula pedunculata subsp. pedunculata EOs and in in vitro axillary shoots EOs. Lavandula pedunculata subsp. lusitanica EOs were predominantly constituted of fenchone and camphor. The antioxidant activity of L. pedunculata subsp. lusitanica EOs was poorer than other Lavandula EOs from Portugal.

Effect of Essential Oils on the Release of TNF-α and CCL2 by LPS-Stimulated THP‑1 Cells

Plants and their constituents have been used to treat diverse ailments since time immemorial. Many plants are used in diverse external and internal formulations (infusions, alcoholic extracts, essential oils (EOs), etc.) in the treatment of inflammation-associated diseases, such as those affecting the respiratory tract or causing gastrointestinal or joint problems, among others. To support the traditional uses of plant extracts, EOs have been assessed for their alleged anti-inflammatory properties. However, the effect of EOs on the release of cytokines and chemokines has been much less reported. Considering their traditional use and commercial relevance in Portugal and Angola, this study evaluated the effect of EOs on the in vitro inhibition of the cytokine tumor necrosis factor-α (TNF-α) and the chemokine (C-C motif) ligand 2 (CCL2) by lipopolysaccharide (LPS)-stimulated human acute monocytic leukemia cells (THP-1 cells). Twenty EOs extracted from eighteen species from seven families, namely from Amaranthaceae (Dysphania ambrosioides), Apiaceae (Foeniculum vulgare), Asteraceae (Brachylaena huillensis, Solidago virgaurea), Euphorbiaceae (Spirostachys africana), Lamiaceae (Lavandula luisieri, Mentha cervina, Origanum majorana, Satureja montana, Thymbra capitata, Thymus mastichina, Thymus vulgaris, Thymus zygis subsp. zygis), Myrtaceae (Eucalyptus globulus subsp. maidenii, Eucalyptus radiata, Eucalyptus viminalis) and Pinaceae (Pinus pinaster) were assayed for the release of CCL2 and TNF-α by LPS-stimulated THP-1 cells. B. huillensis, S. africana, S. montana, Th. mastichina and Th. vulgaris EOs showed toxicity to THP-1 cells, at the lowest concentration tested (10 μg/mL), using the tetrazolium dye assay. The most active EOs in reducing TNF-α release by LPS-stimulated THP-1 cells were those of T. capitata (51% inhibition at 20 μg/mL) and L. luisieri (15-23% inhibition at 30 μg/mL and 78-83% inhibition at 90 μg/mL). L. luisieri EO induced a concentration-dependent inhibition of CCL2 release by LPS‑stimulated THP-1 cells (23%, 54% and 82% inhibition at 10, 30 and 90 μg/mL, respectively). These EOs are potentially useful in the management of inflammatory diseases mediated by CCL2 and TNF‑α, such as atherosclerosis and arthritis.

Essential Oils Extracted from Different Species of the Lamiaceae Plant Family as Prospective Bioagents against Several Detrimental Pests

On the basis of the side effects of detrimental synthetic chemicals, introducing healthy, available, and effective bioagents for pest management is critical. Due to this circumstance, several studies have been conducted that evaluate the pesticidal potency of plant-derived essential oils. This review presents the pesticidal efficiency of essential oils isolated from different genera of the Lamiaceae family including Agastache Gronovius, Hyptis Jacquin, Lavandula L., Lepechinia Willdenow, Mentha L., Melissa L., Ocimum L., Origanum L., Perilla L., Perovskia Kar., Phlomis L., Rosmarinus L., Salvia L., Satureja L., Teucrium L., Thymus L., Zataria Boissier, and Zhumeria Rech. Along with acute toxicity, the sublethal effects were illustrated such as repellency, antifeedant activity, and adverse effects on the protein, lipid, and carbohydrate contents, and on the esterase and glutathione S-transferase enzymes. Chemical profiles of the introduced essential oils and the pesticidal effects of their main components have also been documented including terpenes (hydrocarbon monoterpene, monoterpenoid, hydrocarbon sesquiterpene, and sesquiterpenoid) and aliphatic phenylpropanoid. Consequently, the essential oils of the Lamiaceae plant family and their main components, especially monoterpenoid ones with several bioeffects and multiple modes of action against different groups of damaging insects and mites, are considered to be safe, available, and efficient alternatives to the harmful synthetic pesticides.

Supercritical Carbon Dioxide Antisolvent Fractionation for the Sustainable Concentration of Lavandula luisieri (Rozeira) Riv.- Mart Antimicrobial and Antioxidant Compounds and Comparison with Its Conventional Extracts

Lavandula stoechas subsp. luisieri is a Spanish subspecies from the Lamiaceae family. Its essential oil has been traditionally used for several medical applications though little is known about other extracts. Similar to many other studies aiming to obtain traditional plant extracts to be used in different applications, this work evaluated the antioxidant and antimicrobial activities of Lavandula luisieri extracts and the correlation with their composition. Traditional hydrodistillation and ethanolic maceration were used to obtain the essential oil and the maceration extract, respectively. A green and sustainable methodology was applied to the maceration extract that was under a Supercritical Antisolvent Fractionation process to obtain a fine solid enriched in rosmarinic acid and the terpenes oleanolic and ursolic acids. Antimicrobial activities of all extracts and pure identified compounds (rosmarinic and ursolic acids) were evaluated against five bacterial strains; Listeria monocytogenes, Enterococcus faecium, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli and were compared with the pure compounds identified, rosmarinic and ursolic acids. All strains were sensitive against L. luisieri essential oil. The solid product obtained from the supercritical process was concentrated in the identified actives compared to the maceration extract, which resulted in higher antimicrobial and DPPH scavenging activities. The supercritical sustainable process provided L. luisieri compounds, with retention of their antimicrobial and antioxidant activities, in a powder exemptof organic solvents with potential application in the clinical, food or cosmetic fields.

Lavandula Essential Oils: A Current Review of Applications in Medicinal, Food, and Cosmetic Industries of Lavender

The global essential oil market has been steadily increasing in size over the past few years, and is estimated to reach ca. $7.5 billion USD per annum by 2018. Lavenders ( Lavandula; Lamiaceae) contribute significantly to this market, yielding ca. 1500 tons of essential oils which are primarily used in cosmetics, personal care products, and medicines. Recent literature indicates that these oils may also have applications in food preservation and pest control, among others. The medicinal and pharmaceutical properties of lavenders are chiefly due their essential oils, in particular the major essential oil constituents linalool and linalyl acetate, although certain activities have been attributed to the phenolic compounds. In addition, there is evidence that the major and minor essential oil constituents act synergistically to provide various biological effects. A substantial amount of current research focuses on evaluating the biological activities of lavender essential oils for potential use in traditional and complementary medicine, food systems, cosmetic and fragrance formulations, and insect control products. This review examines recent progress in these areas, and highlights the current and future implications for these economically and medicinally valuable plants.

Antibacterial and antioxidant activity of Portuguese Lavandula luisieri (Rozeira) Rivas-Martinez and its relation with their chemical composition

Lavandula luisieri (Rozeira) Rivas-Martinez is an endemic aromatic Labiatae the Iberian Peninsula, common in semi-arid regions of southern Portugal and southwestern Spain, that produces an active antibacterial essential oil from the leaves and flowers. This work presents the study of the chemical variation in various stages of growth of leaves and flowers of L. luisieri. It has been found that the essential oils are mainly constituted by 1,8-cineol, camphor, linalool and trans-α-necrodil acetate. It was also studied the total phenol content and the antioxidant activity on leaves and flowers. The ethanol extraction from de leaves contents the highest total phenol, important factor for the antioxidant activity of the plant, extract. It has been studied too, the antibacterial activity against Escherichia coli, Salmonella spp. and Staphylococcus aureus. In accordance with the obtained results, the antibacterial activities stand out against Staphylococcus, of the oil of L. luisieri (leaves and flowers).

Phytotoxic and Nematicidal Components of Lavandula luisieri

Several preparations were obtained from the aerial parts of predomesticated Lavandula luisieri, including the essential oil and ethanolic, hexane, and ethyl acetate extractives. Additionally, pilot plant vapor pressure extraction was carried out at a pressure range of 0.5-1.0 bar to give a vapor pressure oil and an aqueous residue. A chemical study of the hexane extract led to the isolation of six necrodane derivatives (1, 2, and 4-7), with four of these (1, 2, 5, and 7) being new, as well as camphor, a cadinane sesquiterpene (9), tormentic acid, and ursolic acid. The EtOAc and EtOH extracts contained a mixture of phenolic compounds with rosmarinic acid being the major component. Workup of the aqueous residue resulted in the isolation of the necrodane 3 and (1R*,2S*,4R*)-p-menth-5-ene-1,2,8-triol (8), both new natural compounds. The structures of the new compounds were established based on their spectroscopic data. The phytotoxic and nematicidal activities of these compounds were evaluated.

Lavender (Lavandula stoechas L.) essential oils attenuate hyperglycemia and protect against oxidative stress in alloxan-induced diabetic rats

BACKGROUND

The present study described the phytochemical profile of Lavandula stoechas essential oils, collected in the area of Ain-Draham (North-West of Tunisia), as well as their protective effects against alloxan-induced diabetes and oxidative stress in rat.

METHODS

Essential oils samples were obtained from the aerial parts of the plant by hydrodistillation and analyzed by GC-MS. Rats were divided into four groups: Healthy Control (HC); Diabetic Control (DC); Healthy + Essential Oils (H + EO) and Diabetic + Essential Oils (D + EO).Antidiabetic and antioxidant activities were evaluated after subacute intraperitoneally injection of Lavandula stoechas essential oils (50 mg/kg b.w., i.p.) to rats during 15 days.

RESULTS

The principal compounds detected are: D-Fenchone (29.28%), α-pinene (23.18%), Camphor (15.97%), Camphene (7.83%), Eucapur (3.29%), Limonene, (2.71%) Linalool, (2.01%) Endobornyl Acetate (1.03%). The essential oils also contained smaller percentages of Tricyclene, Cymene, Delta-Cadinene, Selina-3,7(11)-diene. Furthermore, we found that Lavandula stoechas essential oils significantly protected against the increase of blood glucose as well as the decrease of antioxidant enzyme activities induced by aloxan treatment. Subacute essential oils treatment induced a decrease of lipoperoxidation as well as an increase of antioxidant enzyme activities.

CONCLUSIONS

These findings suggested that lavandula stoechas essential oils protected against diabetes and oxidative stress induced by alloxan treatment. These effects are in partly due to its potent antioxidant properties.

Accumulation of phenolic compounds in in vitro cultures and wild plants of Lavandula viridis L'Hér and their antioxidant and anti-cholinesterase potential

In this study, we evaluated the phenolic profile, antioxidant and anti-cholinesterase potential of different extracts from wild plants and in vitro cultures of Lavandula viridis L'Hér. The HPLC-DAD analysis allowed the identification and quantification of 3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids, and luteolin and pinocembrin. Water/ethanol extract from in vitro cultures contained the highest amount of the identified phenolic compounds (51652.92 mg/kg). To investigate the antioxidant activity we used Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity, Fe(2+) chelation activity and the inhibition of Fe(2+)-induced lipid peroxidation in mouse brain homogenates (in vitro). Overall, all the extracts from both wild plants and in vitro cultures exhibited ability to scavenge free radicals, to chelate Fe(2+) and to protect against lipid peroxidation. In addition, the extracts from L. viridis were active in inhibiting both acetylcholinesterase and butyrylcholinesterase (Ellman's method). Our findings suggest that L. viridis in vitro cultures represent a promising alternative for the production of active metabolites with antioxidant and anti-cholinesterase activity.

Metabolic profile and biological activities of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco: studies on the essential oil and polar extracts

We investigated the metabolic profile and biological activities of the essential oil and polar extracts of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco collected in south Portugal. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that oxygen-containing monoterpenes was the principal group of compounds identified in the essential oil. Camphor (40.6%) and fenchone (38.0%) were found as the major constituents. High-performance liquid chromatography with diode array detection (HPLC-DAD) analysis allowed the identification of hydroxycinnamic acids (3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids) and flavones (luteolin and apigenin) in the polar extracts, with rosmarinic acid being the main compound in most of them. The bioactive compounds from L. pedunculata polar extracts were the most efficient free-radical scavengers, Fe(2+) chelators and inhibitors of malondialdehyde production, while the essential oil was the most active against acetylcholinesterase. Our results reveal that the subspecies of L. pedunculata studied is a potential source of active metabolites with a positive effect on human health.

Inhibitory effect of Lavandula viridis on Fe(2+)-induced lipid peroxidation, antioxidant and anti-cholinesterase properties

In this research, the total phenolic content of a Lavandula viridis methanol extract was evaluated and the phenolic identification and quantification was assessed. Rosmarinic acid and luteolin-7-O-glucoside were the two major compounds identified by HPLC-DAD (ca. 39 and 13g/kg, respectively). This extract showed a strong antioxidant activity in ORAC (2858.39±70.97μmolTE/gextract) and TEAC (967.18±22.57μmolTE/gextract) assays, as well as Fe(2+) chelating and OH scavenging abilities. Furthermore, the extract prevented Fe(2+)-induced lipid peroxidation, by reducing MDA content in mouse brains (in vitro), and inhibited AChE and BChE activities both in vitro and in vivo. These findings demonstrate that the methanol extract from L. viridis is a potential source of natural antioxidants and cholinesterase inhibitors.