Volatile Profiles and DNA Barcodes of Myrtaceae Species with Occurrence in the Brazilian Amazon.

Myrtaceae family includes many species with taxonomic challenges, making it one of the most complex families to identify. This study used DNA barcoding to find molecular markers for species authentication based on the Myrtaceae family's chemical composition and genetic diversity. Essential oils and genetic material were extracted from the leaves of six different species: Eugenia uniflora, E. patrisii, Myrcia splendens, Psidium guajava, P. guineense, and Psidium sp. The samples were analyzed based on compound classes and grouped into two categories. Group I included samples with high amounts of oxygenated sesquiterpenes (3.69-76.05 %) and fatty acid derivatives (0.04-43.59 %), such as E. uniflora, Myrcia splendens, and E. patrisii. Group II included samples P. guajava, P. guineense, and Psidium sp., which had a significant content of monoterpene hydrocarbons (0.69-72.35 %), oxygenated sesquiterpenes (8.06-68.1 %), phenylpropanoids (0.45-22.59 %), and sesquiterpene hydrocarbons (0.27-21.84 %). The PsbA-trnH gene sequences had a high genetic variability, allowing the species to be distinguished. A phylogenetic analysis showed two main clusters with high Bootstrap values corresponding to the subtribes Eugeniineae, Myrciinae, and Pimentinae. The results suggest a weak correlation between genetic and chemical data in these Myrtaceae species.

Antinociceptive and anti-inflammatory activities of Ayapana triplinervis essential oil rich in thymohydroquinone dimethyl ether from Brazil.

Ayapana triplinervis (M.Vahl) R.M.King & H.Rob. (Asteraceae), popularly known as japana, is a tropical, aromatic subshrub widely used as tea to combat some diseases. The essential oil was obtained from the leaves by hydrodistillation (3 h), and the chemical composition was analyzed by gas chromatography coupled to mass spectrometry. For in vivo assays, Mus musculus/Swiss mice were used to evaluate oral acute toxicological (at dose of 2000 mg/kg); peripheral and central analgesic for abdominal contortion (doses of 6.25, 12.5, 25, 50 and 100 mg/kg), hot plate test (12.5, 25, 50, and 100 mg/kg) and formalin (25, 50 and 100 mg/kg); open field test (100 mg/kg); and anti-inflammatory by ear swelling induced by xylene (6.25,12.5, 25, 50, and 100 mg/kg). The yield of A. triplinervis essential oil (AtEO) was 4.6%, and the oxygenated monoterpene 2,5-dimethoxy-p-cymene was the major compound in this study (63.6%). AtEO at a dose of 2,000 mg/kg orally did not change the behavior patterns or mortality of the animals; liver and kidney biochemical levels were similar to the control group, indicating no liver and kidney toxicity. Moreover, AtEO, at doses of 6.25, 12.5, 25, 50, and 100 mg/kg, reduced abdominal contortions by 21%, 54%, 91%, 58%, and 55%, respectively. In the hot plate test, AtEO showed a significant increase in latency time in the 60-min interval at doses of 25 mg/kg (11.3 ± 3.3 s) and 100 mg/kg (11.9 ± 0.9 s). In the first phase of the formalin test, AtEO decreased paw licking time at doses of 25, 50, and 100 mg/kg, with inhibition of 22%, 38%, and 83%; in the second phase, the same doses, decreased licking time with inhibition of 24%, 34%, and 76%. AtEO did not present a significant change in the spontaneous locomotor activity of the animals. Doses of 6.25, 12.5, 25, 50, and 100 mg/kg significantly reduced ear edema induced by topical application of xylene with percentages of 40%, 39%, 54%, 45%, and 45%, respectively. So, AtEO demonstrated low acute oral toxicity and exhibited significant antinociceptive and anti-inflammatory actions, consistent with the use of A. triplinervis in traditional medicine.

Antidepressant Effects of Essential Oils: A Review of the Past Decade (2012-2022) and Molecular Docking Study of Their Major Chemical Components.

Depression is a mental disorder that affects more than 300 million people worldwide. The medications available for treatment take a long time to exhibit therapeutic results and present several side effects. Furthermore, there is a decrease in the quality of life of people suffering from this affliction. Essential oils are traditionally used to relieve the symptoms of depression due to the properties of the constituents of these oils to cross the blood-brain barrier acting on depression-related biological receptors associated with reduced toxicity and side effects. In addition, compared to traditional drugs, they have several administration forms. This review provides a comprehensive assessment of studies on plants whose essential oil has exhibit antidepressant activity in the past decade and the mechanism of action of the major components and models tested. An additional in silico study was conducted with the frequent compounds in the composition of these essential oils, providing a molecular approach to the mechanism of action that has been reported in the past decade. This review is valuable for the development of potential antidepressant medications in addition to providing a molecular approach to the antidepressant mechanism of action of the major volatile compounds that have been reported in the past decade.

Stability and Antioxidant Activity of Pouteria macrophylla Fruit Extract, a Natural Source of Gallic Acid.

Pouteria macrophylla (cutite) fruits are rich in phenolic acids, resulting in antioxidant and skin depigmenting activity. The aim of this study, then, is to evaluate the cutite extract stability under three variations of light, time, and temperature using a Box-Behnken experimental design to analyze through the surface response the variations of the total phenolic content (TPC), antioxidant activity (AA), and gallic acid content (GA). A colorimetric assay was also performed, and a decrease in the darkening index was noticed due to the high phenolic coloration in the presence of light, indicating less degradation to extract stability. The experimental planning showed variations in all responses, and second-order polynomial models were calculated and considered predictable, as well as the effects were significant. The TPC exhibited a variation in less concentrated samples (0.5% p/v) at higher temperatures (90 °C). In contrast, the temperature was the only influential variable for AA, where only higher temperatures (60-90 °C) were able to destabilize the fruit extract. Differently, GA showed only the concentration as the influential variable, exhibiting that neither temperature nor time of exposure could affect the gallic acid content stability of P. macrophylla extract. For this, P. macrophylla extract was shown to be highly stable, providing a great perspective on cosmetic application.

The Volatile Profiles and DNA Barcodes of Lauraceae Species from the Ocotea Complex with Occurrence in the Brazilian Amazon.

The Ocotea complex accommodates most of the taxonomic diversity of Neotropical Lauraceae with economic importance and biological potential attributed to their essential oils (EOs) and extracts. However, the botanical taxonomy has had limitations due to the difficulty of identifying and delimiting species and genera. The chemical and molecular markers of Ocotea complex species in Pará state, Brazil, were assessed according to their EO compositions and DNA sequences of matK, trnL-trnF, and ITS regions. The multivariate analysis of EOs constituents has classified them into two main clusters characterized by oils rich in (I) terpenoids and phenylpropanoids and (II) sesquiterpenes. We conducted a phylogenetic analysis of species based on DNA barcode sequences on the Bayesian Inference (PP: 0.70-1,0) and Maximum Likelihood (BS: 72-100 %). The comparison between the volatile profiles and phylogenetic data indicates two main groups for these species collected from the Ocotea complex.

Variability in the Chemical Composition of Myrcia sylvatica (G. Mey) DC. Essential Oils Growing in the Brazilian Amazon.

Myrcia sylvatica (G. Mey) DC. is known as "insulin plant" because local communities use the infusions of various organs empirically to treat diabetes. The leaves of seven specimens of Myrcia sylvatica (Msy-01 to Msy-07) were collected in the Brazilian Amazon. Furthermore, the essential oils were extracted by hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry, and their chemical compositions were submitted to multivariate analysis (Principal Component Analysis and Hierarchical Cluster Analysis). The multivariate analysis displayed the formation of four chemical profiles (chemotypes), described for the first time as follows: chemotype I (specimen Msy-01) was characterized by germacrene B (24.5%), γ-elemene (12.5%), and ß-caryophyllene (10.0%); chemotype II (specimens Msy-03, -06 and -07) by spathulenol (11.1-16.0%), germacrene B (7.8-20.7%), and γ-elemene (2.9-7.6%); chemotype III (Msy-04 and -05) by spathulenol (9.8-10.1%), ß-caryophyllene (2.5-10.1%), and δ-cadinene (4.8-5.6%); and chemotype IV, (Msy-02) by spathulenol (13.4%), caryophyllene oxide (15.0%), and α-cadinol (8.9%). There is a chemical variability in the essential oils of Myrcia sylvatica occurring in the Amazon region.

Chemical Composition and Variability of the Volatile Components of Myrciaria Species Growing in the Amazon Region.

Myrciaria (Myrtaceae) species have been well investigated due to their chemical and biological relevance. The present work aimed to carry out the chemotaxonomic study of essential oils of the species M. dubia, M. floribunda, and M. tenella, sampled in the Brazilian Amazon and compare them with the volatile compositions from other Myrciaria species reported to Brazil and Colombia. The leaves of six Myrciaria specimens were collected (PA, Brazil) during the dry season, and their chemical compositions were analyzed by gas chromatography-mass spectrometer (GC-MS) and gas chromatography-flame ionization detector (GC-FID). The main compounds identified in the essential oils were monoterpenes with pinane and menthane skeletons, followed by sesquiterpenes with caryophyllane and cadinane skeletons. Among the sampled Myrciaria specimens, five chemical profiles were reported for the first time: profile I (M. dubia, α-pinene, 54.0-67.2%); profile II (M. floribunda, terpinolene 23.1%, α-phellandrene 17.7%, and γ-terpinene 8.7%); profile III (M. floribunda, γ-cadinene 17.5%, and an unidentified oxygenated sesquiterpene 15.0%); profile IV (M. tenella, E-caryophyllene 43.2%, and α-humulene 5.3%); and profile V (M. tenella, E-caryophyllene 19.1%, and caryophyllene oxide 41.1%). The Myrciaria chemical profiles showed significant variability in extraction methods, collection sites, plant parts, and genetic aspects.

Essential Oil Chemotypes and Genetic Variability of Cinnamomum verum Leaf Samples Commercialized and Cultivated in the Amazon.

Cinnamomum verum (Lauraceae), also known as "true cinnamon" or "Ceylon cinnamon" has been widely used in traditional folk medicine and cuisine for a long time. The systematics of C. verum presents some difficulties due to genetic variation and morphological similarity between other Cinnamomum species. The present work aimed to find chemical and molecular markers of C. verum samples from the Amazon region of Brazil. The leaf EOs and the genetic material (DNA) were extracted from samples cultivated and commercial samples. The chemical composition of the essential oils from samples of C. verum cultivated (Cve1-Cve5) and commercial (Cve6-c-Cv9-c) was grouped by multivariate statistical analysis of Principal Component Analysis (PCA). The major compounds were rich in benzenoids and phenylpropanoids, such as eugenol (0.7-91.0%), benzyl benzoate (0.28-76.51%), (E)-cinnamyl acetate (0.36-32.1%), and (E)-cinnamaldehyde (1.0-19.73%). DNA barcodes were developed for phylogenetic analysis using the chloroplastic regions of the matK and rbcL genes, and psbA-trnH intergenic spacer. The psbA-trnH sequences provided greater diversity of nucleotides, and matK confirmed the identity of C. verum. The combination of DNA barcode and volatile profile was found to be an important tool for the discrimination of C. verum varieties and to examine the authenticity of industrial sources.

Secondary Metabolic Profile as a Tool for Distinction and Characterization of Cultivars of Black Pepper (Piper nigrum L.) Cultivated in Pará State, Brazil.

This study evaluated the chemical compositions of the leaves and fruits of eight black pepper cultivars cultivated in Pará State (Amazon, Brazil). Hydrodistillation and gas chromatography-mass spectrometry were employed to extract and analyze the volatile compounds, respectively. Sesquiterpene hydrocarbons were predominant (58.5-90.9%) in the cultivars "Cingapura", "Equador", "Guajarina", "Iaçará", and "Kottanadan", and "Bragantina", "Clonada", and "Uthirankota" displayed oxygenated sesquiterpenoids (50.6-75.0%). The multivariate statistical analysis applied using volatile composition grouped the samples into four groups: γ-Elemene, curzerene, and δ-elemene ("Equador"/"Guajarina", I); δ-elemene ("Iaçará"/"Kottanadan"/"Cingapura", II); elemol ("Clonada"/"Uthirankota", III) and α-muurolol, bicyclogermacrene, and cubebol ("Bragantina", IV). The major compounds in all fruit samples were monoterpene hydrocarbons such as α-pinene, ß-pinene, and limonene. Among the cultivar leaves, phenolics content (44.75-140.53 mg GAE·g-1 FW), the enzymatic activity of phenylalanine-ammonia lyase (20.19-57.22 µU·mL-1), and carotenoids (0.21-2.31 µg·mL-1) displayed significant variations. Due to black pepper's susceptibility to Fusarium infection, a molecular docking analysis was carried out on Fusarium protein targets using each cultivar's volatile components. F. oxysporum endoglucanase was identified as the preferential protein target of the compounds. These results can be used to identify chemical markers related to the susceptibility degree of black pepper cultivars to plant diseases prevalent in Pará State.

Essential Oil Composition and DNA Barcode and Identification of Aniba species (Lauraceae) Growing in the Amazon Region.

Lauraceae species are widely represented in the Amazon, presenting a significant essential oil yield, large chemical variability, various biological applications, and high economic potential. Its taxonomic classification is difficult due to the accentuated morphological uniformity, even among taxa from a different genus. For this reason, the present work aimed to find chemical and molecular markers to discriminate Aniba species collected in the Pará State (Brazil). The chemical composition of the essential oils from Aniba canelilla, A. parviflora, A. rosaeodora, and A. terminalis were grouped by multivariate statistical analysis. The major compounds were rich in benzenoids and terpenoids such as 1-nitro-2-phenylethane (88.34-70.85%), linalool (15.2-75.3%), α-phellandrene (36.0-51.8%), and ß-phellandrene (11.6-25.6%). DNA barcodes were developed using the internal transcribed spacer (ITS) nuclear region, and the matK, psbA-trnH, rbcL, and ycf1 plastid regions. The markers psbA-trnH and ITS showed the best discrimination for the species, and the phylogenic analysis in the three- (rbcL + matK + trnH - psbA and rbcL + matK + ITS) and four-locus (rbcL + matK + trnH - psbA + ITS) combination formed clades with groups strongly supported by the Bayesian inference (BI) (PP:1.00) and maximum likelihood (ML) (BS ≥ 97%). Therefore, based on statistical multivariate and phylogenetic analysis, the results showed a significant correlation between volatile chemical classes and genetic characteristics of Aniba species.

Chemical composition and biological activities of two chemotype-oils from Cinnamomum verum J. Presl growing in North Brazil.

Chemical composition and antioxidant and antifungal action of the oils from leaves and wood bark of two chemotypes of Cinnamomum verum J. Presl were evaluated. Plants were sampled in the cities of São Luís and Santa Inês, state of Maranhão, Brazil. GC-MS and GC-FID, DPPH radical scavenging, and in vitro test against the phytopathogenic fungus Colletotrichum musae were used to perform these analyses. Cinnamomum verum is worldwide known as Cinnamon, highlighted for its extensive use in the cooking of diverse cultures of the world, and as a medicinal plant to treat environmental viral diseases. In the leaf oil of São Luís chemotype, eugenol (93.6%) was the main constituent, while in Santa Inês chemotype, it was benzyl benzoate (95.3%). In the bark wood oil of São Luís chemotype, (E)-cinnamaldehyde (89.3%) was the main constituent, while in Santa Inês chemotype, they were benzyl benzoate (23.3%), linalool (14.0%), (E)-caryophyllene (9.1%), caryolan-8-ol (7.2%) and borneol (4.7%). Leaf oils from both chemotypes showed strong to moderate antifungal activity, reaching 100% efficacy in eugenol-containing oils and above 70% in benzyl benzoate oils. In the antioxidant evaluation, the chemotype with a high eugenol content presented an inhibitory concentration higher than 80%, compared to Trolox. The leaf oils of the two C. verum chemotypes showed significant antifungal and antioxidant potential, considering their economic use as a functional and nutraceutical food supplement.

Volatiles of Black Pepper Fruits (Piper nigrum L.).

Black pepper (Piper nigrum) is historically one of the most important spices and herbal medicines, and is now cultivated in tropical regions worldwide. The essential oil of black pepper fruits has shown a myriad of biological activities and is a commercially important commodity. In this work, five black pepper essential oils from eastern coastal region of Madagascar and six black pepper essential oils from the Amazon region of Brazil were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The major components of the essential oils were α-pinene, sabinene, ß-pinene, δ-3-carene, limonene, and ß-caryophyllene. A comparison of the Madagascar and Brazilian essential oils with black pepper essential oils from various geographical regions reported in the literature was carried out. A hierarchical cluster analysis using the data obtained in this study and those reported in the literature revealed four clearly defined clusters based on the relative concentrations of the major components.

Variations in Essential Oil Compositions of Lavandula pubescens (Lamiaceae) Aerial Parts Growing Wild in Yemen.

Lavandula pubescens Decne. is one of five Lavandula species growing wild in Yemen. The plant is used in Yemeni traditional medicine, and the essential oil tends to be rich in carvacrol. In this work, L. pubescens was collected from eight different locations in Yemen, the essential oils obtained by hydrodistillation, and the oils analyzed by gas chromatography/mass spectrometry (GC/MS). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to differentiate between the L. pubescens samples. The essential oils were rich in carvacrol (60.9 - 77.5%), with lesser concentrations of carvacrol methyl ether (4.0 - 11.4%), caryophyllene oxide (2.1 - 6.9%), and terpinolene (0.6 - 9.2%). The essential oil compositions in this study showed very high similarity, but it was possible to discern two separate groups based on minor components, in particular the concentrations of terpinolene, carvacrol methyl ether, m-cymen-8-ol, and caryophyllene oxide.

Composition and cytotoxic and antioxidant activities of the oil of Piper aequale Vahl.

BACKGROUND: Piper aequale Vahl is a small shrub that grows in the shadow of large trees in the Carajás National Forest, Municipality of Parauapebas, Para state, Brazil. The local people have used the plant against rheumatism and inflammation. METHODS: The essential oil of the aerial parts was extracted and analyzed by GC and GC-MS. The MTT colorimetric assay was used to measuring the cytotoxic activity of the oil against human cancer lines. The determination of antioxidant activity of the oil was conducted by DPPH radical scavenging assay. RESULTS: The main constituents were δ-elemene (18.92 %), ß-pinene (15.56 %), α-pinene (12.57 %), cubebol (7.20 %), ß-atlantol (5.87 %), and bicyclogermacrene (5.51 %), totalizing 65.63 % of the oil. The oil displayed a strong in vitro cytotoxic activity against the human cancer cell lines HCT-116 (colon) and ACP03 (gastric) with IC50values of 8.69 µg/ml and 1.54 µg/ml, respectively. The oil has induced the apoptosis in a gastric cancer cells in all tested concentration (0.75-3.0 µg/ml), after 72 h of treatment, when compared to negative control (p < 0.001). Also, the oil showed a significant antioxidant activity (280.9 ± 22.2 mg TE/ml), when analyzed as Trolox equivalent, and a weak acetylcholinesterase inhibition, with a detection limit of 100 ng, when compared to the physostigmine standard (1.0 ng). CONCLUSION: The higher cell growth inhibition induced by the oil of P. aequale is probably due to its primary terpene compounds, which were previously reported in the proliferation inhibition, in stimulation of apoptosis and induction of cell cycle arrest in malignant cells.

Antibacterial action against food-borne microorganisms and antioxidant activity of carvacrol-rich oil from Lippia origanoides Kunth.

BACKGROUND: Lippia origanoides Kunth from Northeast Brazil is a plant of pleasant odor used by local people as a food seasoning in substitution the oregano where its carvacrol-rich oil has showed significant antimicrobial activity against human pathogens. METHODS: GC and GC-MS analyzed the plant oil composition and its antibacterial activity was evaluated by disk diffusion and microdilution broth methods. The determination of oil antioxidant activity was made by DPPH radical scavenging assay. Oil toxicity was performed on mice. RESULTS: The main constituents of the oil were carvacrol (47.2%), thymol (12.8%), p-cymene (9.7%), and p-methoxythymol (7.4%). The oil was active against the bacteria of Bacillus cereus, B. subtilis, and Salmonella typhimurium, except for Pseudomonas aeruginosa. The antioxidant activity has displayed a high dose-response (r(2) = 0.92), with the inhibition of DPPH radical from 15 to 82%, at concentrations from 5 to 50 µg/mL, and also by the ß-carotene bleaching assay, which showed a high inhibition of 85.2 ± 6.8 %, corresponding to about 80% of the inhibition of Trolox (93.4 ± 0.7%), used as a standard. The lethal dose (LD50) of the oil was determined in 1673.84 mg mL(-1). CONCLUSION: The results confirmed that the oil of L. origanoides could be utilized for the prevention of food bacterial growth, and as an antioxidative agent for retardation of food oxidation process. The oil has low toxicity, allowing its application in the food industry. Graphical Abstract Aerial parts of Lippia origanoides Kunth.

Antinociceptive Activity and Toxicity Evaluation of the Fatty Oil from Plukenetia polyadenia Mull. Arg. (Euphorbiaceae).

Seed oil (Pp-oil) of Plukenetia polyadenia is used by native people of the Brazilian Amazon against arthritis and rheumatism, spreading it on the arms and legs to reduce the pain and inflammation. Pp-oil was obtained by pressing dried seeds at room temperature to give a 47.0% yield of oil. It was then subjected to fatty acid composition analysis. The principal fatty acids were linoleic acid (46.5%), α-linolenic acid (34.4%) and oleic acid (13.9%). Then, it was evaluated for its antinociceptive activity in mice, using the acetic acid-induced abdominal writhing, hot plate and formalin test models. Additionally, its toxicity was determined. The Pp-oil proved to have no toxicological effects, showing dose-dependent antinociceptive effect under chemical stimulation. At oral doses of 25-100 mg/kg, Pp-oil significantly reduced the abdominal writhes in the writhing test. A higher oral dose of 200 mg/kg did not induce alterations in the latency time of the hot plate test when compared to the control, suggesting an analgesic activity of peripheral origin. At oral doses of 50 and 100 mg/kg, the Pp-oil significantly reduced the second phase of the algic stimulus in the formalin test. In addition, the antinociception of Pp-oil was reversed by naloxone in the evaluation of its mechanism of action. Therefore, the Pp-oil proved to be safe at very high doses and to show significant analgesic properties. The role of Pp-oil is still being investigated with respect the mechanism of action, but the results suggest that opiod receptors could be involved in the antinociception action observed for the oil of P. polyadenia.

Antifungal activity and computational study of constituents from Piper divaricatum essential oil against Fusarium infection in black pepper.

Fusarium disease causes considerable losses in the cultivation of Piper nigrum, the black pepper used in the culinary world. Brazil was the largest producer of black pepper, but in recent years has lost this hegemony, with a significant reduction in its production, due to the ravages produced by the Fusarium solani f. sp. piperis, the fungus which causes this disease. Scientific research seeks new alternatives for the control and the existence of other Piper species in the Brazilian Amazon, resistant to disease, are being considered in this context. The main constituents of the oil of Piper divaricatum are methyleugenol (75.0%) and eugenol (10.0%). The oil and these two main constituents were tested individually at concentrations of 0.25 to 2.5 mg/mL against F. solani f. sp. piperis, exhibiting strong antifungal index, from 18.0% to 100.0%. The 3D structure of the ß-glucosidase from Fusarium solani f. sp. piperis, obtained by homology modeling, was used for molecular docking and molecular electrostatic potential calculations in order to determine the binding energy of the natural substrates glucose, methyleugenol and eugenol. The results showed that ß-glucosidase (Asp45, Arg113, Lys146, Tyr193, Asp225, Trp226 and Leu99) residues play an important role in the interactions that occur between the protein-substrate and the engenol and methyleugenol inhibitors, justifying the antifungal action of these two phenylpropenes against Fusarium solani f. sp. piperis.

Chemical Compositions and Enantiomeric Distributions of Foliar Essential Oils of Chamaecyparis lawsoniana (A. Murray bis) Parl, Thuja plicata Donn ex D. Don, and Tsuga heterophylla Sarg.

As part of our continuing interest in the essential oil compositions of gymnosperms, particularly the distribution of chiral terpenoids, we have obtained the foliar essential oils of Chamaecyparis lawsoniana (two samples), Thuja plicata (three samples), and Tsuga heterophylla (six samples) from locations in the state of Oregon, USA. The essential oils were obtained via hydrodistillation and analyzed by gas chromatographic techniques, including chiral gas chromatography-mass spectrometry. The major components in C. lawsoniana foliar essential oil were limonene (27.4% and 22.0%; >99% (+)-limonene), oplopanonyl acetate (13.8% and 11.3%), beyerene (14.3% and 9.0%), sabinene (7.0% and 6.5%; >99% (+)-sabinene), terpinen-4-ol (5.0% and 5.3%; predominantly (+)-terpinen-4-ol), and methyl myrtenate (2.0% and 5.4%). The major components in T. plicata essential oil were (-)-α-thujone (67.1-74.6%), (+)-ß-thujone (7.8-9.3%), terpinen-4-ol (2.7-4.4%; predominantly (+)-terpinen-4-ol), and (+)-sabinene (1.1-3.5%). The major components in T. heterophylla essential oil were myrcene (7.0-27.6%), α-pinene (14.4-27.2%), ß-phellandrene (6.6-19.3%), ß-pinene (6.4-14.9%; >90% (-)-ß-pinene), and (Z)-ß-ocimene (0.7-11.3%). There are significant differences between the C. lawsoniana essential oils from wild trees in Oregon and those of trees cultivated in other geographical locations. The essential oil compositions of T. plicata are very similar, regardless of the collection site. There are no significant differences between T. heterophylla essential oils from the Oregon Coastal Range or those from the Oregon Cascade Range. Comparing essential oils of the Cupressaceae with the Pinaceae, there are some developing trends. The (+)-enantiomers seem to dominate for α-pinene, camphene, sabinene, ß-pinene, limonene, terpinen-4-ol, and α-terpineol in the Cuppressaceae. On the other hand, the (-)-enantiomers seem to predominate for α-pinene, camphene, ß-pinene, limonene, ß-phellandrene, terpinen-4-ol, and α-terpineol in the Pinaceae.

Polymer-Based Wound Dressings Loaded with Essential Oil for the Treatment of Wounds: A Review.

Wound healing can result in complex problems, and discovering an effective method to improve the healing process is essential. Polymeric biomaterials have structures similar to those identified in the extracellular matrix of the tissue to be regenerated and also avoid chronic inflammation, and immunological reactions. To obtain smart and effective dressings, bioactive agents, such as essential oils, are also used to promote a wide range of biological properties, which can accelerate the healing process. Therefore, we intend to explore advances in the potential for applying hybrid materials in wound healing. For this, fifty scientific articles dated from 2010 to 2023 were investigated using the Web of Science, Scopus, Science Direct, and PubMed databases. The principles of the healing process, use of polymers, type and properties of essential oils and processing techniques, and characteristics of dressings were identified. Thus, the plants Syzygium romanticum or Eugenia caryophyllata, Origanum vulgare, and Cinnamomum zeylanicum present prospects for application in clinical trials due to their proven effects on wound healing and reducing the incidence of inflammatory cells in the site of injury. The antimicrobial effect of essential oils is mainly due to polyphenols and terpenes such as eugenol, cinnamaldehyde, carvacrol, and thymol.

Lippia alba essential oil: A powerful and valuable antinociceptive and anti-inflammatory medicinal plant from Brazil.

ETHNOPHARMACOLOGICAL RELEVANCE: In Brazilian popular medicine, Lippia alba leaves are used in teas to treat pain and inflammatory diseases. AIM OF THE STUDY: to evaluate the chemical composition, antinociceptive, and anti-inflammatory activities of Lippia alba essential oil and its major compound geraniol. MATERIAL AND METHODS: Lippia alba leaves were collected in Pará state, Brazil. The leaf essential oil was obtained using a modified Clevenger-type extractor. Then, the oil was analyzed by GC and GC-MS analyses. To evaluate the toxicity of LaEO and geraniol, the doses of 50, 300, and 2000 mg/kg were used in a mouse model. For antinociception tests, abdominal contortion, hot plate, and formalin tests were used; all groups were treated with LaEO and geraniol at doses of 25, 50, and 100 mg/kg; and to evaluate inflammation using the ear edema model. RESULTS: The constituents identified in the highest content were oxygenated monoterpenes: geraniol (37.5%), geranial (6.7%) and neral (3.8%). The animals treated with LaEO and geraniol demonstrated atypical behaviors with aspects of lethargy and drowsiness, characteristics of animals in a state of sedation; the relative weights showed no significant difference compared to the controls. In the abdominal contortion test, LaEO at 25 mg/kg, 50 mg/kg doses, and 100 mg/kg reduced the number of contortions, representing a percentage reduction of 84.64%, 81.23%, and 66.21% respectively. In the hot plate test, LaEO and geraniol increased the latency time at doses of 25, 50, and 100 mg/kg in all test periods; there was no statistical difference between LaEO and geraniol. In the first phase of the formalin test, only doses of 25 mg/kg and 100 mg/kg of LaEO showed significant activity, reducing the latency time by 53.40% and 58.90%. LaEO at doses of 25 mg/kg and 100 mg/kg reduced the size of the edema, demonstrating an anti-inflammatory activity of 59.38% (25 mg/kg) and 50% (100 mg/kg). CONCLUSION: Lippia alba essential oil and geraniol showed central/peripheral analgesic and anti-inflammatory potential and can be used as an alternative or complementary treatment to conventional drugs. More studies are needed to evaluate its action mechanisms and its analgesic effects.