Main Components Of Essential Oil Research Articles

Essential oil analysis of Rhaponticum repens (L.) Hidalgo, and its application in green synthesis of iron nanoparticles to remove Cr (VI) ions from aqueous solutions

Acroptilon repens is a widespread weed in Asia, and has a complicated taxonomy. Recent taxonomical treatment explored that Acroptilon species must be classified in the genus Rhaponticum. Therefore, the scientific name of this species has been converted into Rhaponticum repens. In the current study, essential oil composition, and its ability to green synthesis of iron nanoparticles for future use to adsorb Cr (VI) ions pollution of aquatic solution were evaluated for the first time. The GC-MS analysis revealed oxygenated monoterpenes constituted great proportion of the essential oil, with 1,8-cineole and camphor as the main essential oil components. Several appropriate methods, including UV-Vis, FTIR, XRD, SEM, DLS, and VSM revealed the green synthesis of a mixture of Fe3O4 and Fe2O3 nanoparticles by the extracted essential oil. Sizes of the produced nanoparticles were not equal and detected in the range of 3 to 50 nm, with an average size of 31.5 nm and the magnetic property of 15 emu/g. The green-synthesized nanoparticles could adsorb Cr (VI) ions pollution from aquatic solutions. However, under an optimum condition, the Cr (VI) ions adsorption capacity and removal were 167.6 mg/g and 91%, respectively. Findings revealed the major essential oil composition highly differed from those reported in the previous phytochemical studies. Although the synthesized nanoparticles were not uniform, they could remove Cr (VI) ions pollution.

The effect of different hydrodistillation times on the composition and yield of bergamot (Citrus bergamia Risso) peel essential oil and a comparison of the cold‐pressing method

AbstractBergamot (Citrus bergamia Risso) is not consumed as fresh fruit as other members of Citrus. Bergamot essential oil has a unique aroma. Bergamot essential oil is a very valuable product used in perfumery, cosmetics, aromatherapy and food industry due to its beautiful scent and functional properties. As with other Citrus species, the composition of bergamot essential oil can vary according to harvest time, climate and extraction technology. Bergamot essential oil could be obtained by cold press extraction or distillation method. Within the scope of the study, the effect of four different hydrodistillation (HD) times (5, 10, 60 and 120 min) on the composition of bergamot essential oil obtained from Turkish fruits was investigated. In the first 60 min, 96.11% of the total essential oil was obtained. Research findings have shown that the distillation time is quite effective in the composition of bergamot essential oil. Limonene, linalool and linalyl acetate, which are the main components of bergamot essential oil, varied in the range, 42.36%–53.25%, 5.59%–12.18% and 20.84%–26.73%, respectively, with respect to distillation time. In cold press method, bergamot essential oil has lower linalool/linalyl acetate ratio (0.15) compared to HD method and a higher quality essence was obtained.

Contributions of γ-Aminobutyric Acid (GABA) Receptors for the Activities of Pectis brevipedunculata Essential Oil against Drosophila suzukii and Pollinator Bees.

The γ-aminobutyric acid (GABA) receptors play pivotal roles in the transmission of neuronal information in the nervous system of insects, which has led these proteins to be targeted by synthetic and natural products. Here, we assessed the insecticidal potential of the essential oil of Pectis brevipedunculata (Gardner) Sch. Bip., a neotropical Asteraceae plant used in traditional medicine, for controlling Drosophila suzukii (Matsumura) adults by feeding exposure. By using in silico approaches, we disentangle the contribution of GABA receptors and other potential neuronal targets (e.g., acetylcholinesterase, glutathione-S-transferases) in insects that may explain the essential oil differential activities against D. suzukii and two essential pollinator bees (Apis mellifera Linnaeus and Partamona helleri Friese). Neral (26.7%) and geranial (33.9%) were the main essential oil components which killed D. suzukii with an estimated median lethal concentration (LC50) of 2.25 µL/mL. Both pollinator forager bee species, which would likely contact this compound in the field, were more tolerant to the essential oil and did not have their diet consumptions affected by the essential oil. Based on the molecular predictions for the three potential targets and the essential oil main components, a higher affinity of interaction with the GABA receptors of D. suzukii (geranial -6.2 kcal/mol; neral -5.8 kcal/mol) in relation to A. mellifera (geranial -5.2 kcal/mol; neral -4.9 kcal/mol) would contribute to explaining the difference in toxicities observed in the bioassays. Collectively, our findings indicated the involvement of GABA receptors in the potential of P. brevipedunculata essential oil as an alternative tool for controlling D. suzukii.

Comparison of the cytotoxicity and zebrafish embryo toxicity of insect repellent ingredients: p-Menthane-3,8-diol synthesized by green chemistry from Eucalyptus citriodora and N,N-diethyl-meta-toluamide

Bio-sourced insect repellents are becoming more popular due to their safer applications. Known for its strong fly-repellent property, Cis, trans-para-menthane-3,8-diol (PMD) is the main component of the lemon eucalyptus essential oil and is synthesized from citronellal. In April 2005, US Centers for Disease Control approved two fly repellents that do not contain N,N-diethyl-meta-toluamide (DEET), including PMD. Due to the intentional and pervasive human exposure caused by DEET as insect repellent, concerns have been raised about its toxicological profile and potential harm to people. We hypothesized PMD would have a different toxicological profile than DEET. We synthesized PMD from Eucalyptus citriodora using green chemistry methods and analyzed its structures by 1H-NMR,13C-NMR, and GC/MS spectral methods. We used MTS assay to determine the percentage inhibition of PMD and DEET on keratinocyte (human epidermal keratinocyte [HaCaT]) cells. The xCelligence system was used and followed at real time. Effects of PMD and DEET on zebrafish embryo development were monitored and levels of lipid peroxidation, glutathione-S-transferase (GST), superoxide dismutase (SOD), and acetylcholinesterase (AchE) were evaluated at 72 h post-fertilization using spectrophotometric methods. Our results showed that while DEET inhibited human keratinocyte cell growth, while imporved cell viability and proliferation was exposed in PMD exposed group. In zebrafish embryos, PMD was less toxic in terms of development, oxidant-antioxidant status, and AChE activities than DEET. Based on these results we suggest an efficient method using green chemistry for the synthesis of PMD, which is found to be less toxic in zebrafish embryos and human keratinocyte cells.

Identification and variation analysis of the composition and content of essential oil and fragrance compounds in Phoebe zhennan wood at different tree ages.

Wood essential oil and wood products with special fragrances are high value-added forest products. Despite the availability of essential oil and volatile organic compounds (VOCs) from Phoebe zhennan wood, their variation and dependence on tree age have not been examined. After essential oil extraction and wood processing, the yields and compositions of essential oils and VOCs in wood from P. zhennan trees of different ages (10a, 30a, and 80a) were determined. The yield of essential oil from 30a wood was significantly greater than that from 10a and 80a wood. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) revealed 672 and 41 volatile compounds, respectively, in the essential oil and wood, the majority of which exhibited large fluctuations in relative content and composition depending on tree age. Sesquiterpenoids, fatty acids and conjugates may greatly contribute to the main components of essential oil from wood. Almost all major sesquiterpenoid compounds, such as caryophyllene α-oxide, eudesmo, and cubebene, were identified in the essential oils from the 30a and 80a wood, and their relative contents were much greater than those in the 10a wood. The main components of the wood fragrance were sesquiterpenoids. The types and relative contents of sesquiterpenoids from wood increased with tree age. These results suggest that choosing wood from trees of a suitable age will significantly improve the efficiency of wood utilization.

Artificial Biosynthetic Pathway for Efficient Synthesis of Vanillin, a Feruloyl-CoA-Derived Natural Product from Eugenol.

Eugenol, the main component of essential oil from the Syzygium aromaticum clove tree, has great potential as an alternative bioresource feedstock for biosynthesis purposes. Although eugenol degradation to ferulic acid was investigated, an efficient method for directly converting eugenol to targeted natural products has not been established. Herein we identified the inherent inhibitions by simply combining the previously reported ferulic acid biosynthetic pathway and vanillin biosynthetic pathway. To overcome this, we developed a novel biosynthetic pathway for converting eugenol into vanillin, by introducing cinnamoyl-CoA reductase (CCR), which catalyzes conversion of coniferyl aldehyde to feruloyl-CoA. This approach bypasses the need for two catalysts, namely coniferyl aldehyde dehydrogenase and feruloyl-CoA synthetase, thereby eliminating inhibition while simplifying the pathway. To further improve efficiency, we enhanced CCR catalytic efficiency via directed evolution and leveraged an artificialvanillin biosensor for high-throughput screening. Switching the cofactor preference of CCR from NADP+ to NAD+ significantly improved pathway efficiency. This newly designed pathway provides an alternative strategy for efficiently biosynthesizing feruloyl-CoA-derived natural products using eugenol.

Towards Sustainable Pest Management: Toxicity, Biochemical Effects, and Molecular Docking Analysis of Ocimum basilicum (Lamiaceae) Essential Oil on Agrotis ipsilon and Spodoptera littoralis (Lepidoptera: Noctuidae)

Over the last decade, essential oils (EOs) have become potential ingredients for insecticide formulations due to their widespread availability and perceived safety. Therefore, this study aimed to evaluate the toxicity and biochemical efficacy of basil (Ocimum basilicum) (Lamiaceae) against two destructive pests Noctuidae, Agrotis ipsilon (Hufnagel) and Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae). In addition, a molecular docking study was performed to gain insight into the binding pattern between glutathione S-transferase (GST) and linalool, the main component of EO. GC–MS analysis of O. basilicum EO revealed that linalool is the most abundant compound (29.34%). However, the toxicity tests showed no significant difference between the values of LC50 of O. basilicum EO to A. ipsilon and S. littoralis. On the other hand, the sublethal experiments indicated that treating the second instar larvae with LC15 or LC50 values of O. basilicum EO significantly prolonged the larval duration in both insects, compared to the control. Regarding the biochemical effect of O. basilicum EO, the treatments significantly impacted the activity of detoxification enzymes. A notable elevation in glutathione S-transferase (GST) activity was recorded in A. ipsilon larvae compared with a reduction in S. littoralis larvae. The molecular docking analysis revealed that linalool bonded with the amino acid serine (SER 9) of GST, indicating its binding affinity with the enzyme. The obtained results could offer valuable insights into the mode of action of O. basilicum and can encourage the adoption of sustainable pest control practices that incorporate essential oils.

RELATIONSHIP BETWEEN BIOCHEMICAL INDICATORS AND PHENOTYPICAL CHARACTERISTICS OF THYME (THYMUS VULGARIS L.)

Introduction. Thyme (Thymus vulgaris L.) is a sought-after medicinal crop, the raw materials of which are included in the Pharmacopoeias of several countries and are widely used in scientific medicine. Due to the presence of strong intraspecific diversity in thyme, it seems interesting to identify phenotypic characteristics that most likely indicate the presence of certain pharmacologically significant compounds. The presence of such information will allow targeted selection both in natural populations and during the hybridization of cultivars and the development of new varieties. The purpose of the work was to identify phenotypic traits indicating a high content of essential oil and thymol in thyme, the amount of phenolic compounds, flavonoids and tannins. Material and methods. Samples and varieties of thyme from different geographical origins were selected as objects. Biometric, anatomical indicators and yield were determined in the flowering phase. The essential oil content was determined by Clevenger hydrodistillation method. Component composition was determined by gas chromatography. The amount of phenolic compounds and tannins according to the Folin-Ciocalteu method in aqueous-alcoholic extract calculated as gallic acid. The determination of flavonoids in the aqueous-alcoholic extract was carried out using the spectrophotometryс method calculated as rutin. Results. As a result of the research, no signs were found indicating a high content of essential oil. Flavonoid content calculated as rutin had a negative correlation (−0.72) with stomatal density. A negative relationship was noted between the intensity of coloring of the pistil and anthers and the content of the total phenolic compounds calculated as gallic acid (0.71 and 0.72, respectively). Large stomata on both the underside and upper side of the leaf may indicate a high tannin content (0.8 and 0.88). All studied components of common thyme belonged to the thymol type, and the content of this component ranged from 37.6 to 80.8%. An increased content of thymol in essential oil is observed such signs as an elongated leaf shape (leaf index R = 0.78), lack of downward curling of the edges of the leaf blade (R = –0.78) and pronounced veins on the underside of the leaf (R = 0.92). Large stomata on the lower epidermis also indicate an increased proportion of thymol in the essential oil (R = 0.78). When analyzing the interdependence between the content of the main components of essential oil, it was noted that there is a close negative correlation between the content of p-cymene and thymol (R = –0.91) and carvacrol (R = –0.88). Conclusion. As a result of the research, phenotypic and anatomical characteristics were identified that make it possible to diagnose promising samples of common thyme, which will help speed up the selection process.

Full-Length Transcriptome Sequencing and RNA-Seq Analysis Offer Insights into Terpenoid Biosynthesis in Blumea balsamifera (L.) DC.

Blumea balsamifera (L.) DC., an important economic and medicinal herb, has a long history of being used as a traditional Chinese medicine. Its leaves have always been used as a raw material for the extraction of essential oils, comprising large amounts of terpenoids, which have good therapeutic effects on many diseases, such as eczema, bacterial infection, and hypertension. However, the genetic basis of terpenoid biosynthesis in this plant is virtually unknown on account of the lack of genomic data. Here, a combination of next-generation sequencing (NGS) and full-length transcriptome sequencing was applied to identify genes involved in terpenoid biosynthesis at five developmental stages. Then, the main components of essential oils in B. balsamifera were identified using GC-MS. Overall, 16 monoterpenoids and 20 sesquiterpenoids were identified and 333,860 CCS reads were generated, yielding 65,045 non-redundant transcripts. Among these highly accurate transcripts, 59,958 (92.18%) transcripts were successfully annotated using NR, eggNOG, Swissprot, KEGG, KOG, COG, Pfam, and GO databases. Finally, a total of 56 differently expressed genes (DEGs) involved in terpenoid biosynthesis were identified, including 38 terpenoid backbone genes and 18 TPSs, which provide a significant amount of genetic information for B. balsamifera. These results build a basis for resource protection, molecular breeding, and the metabolic engineering of this plant.

Content analysis, nanoparticle forming potential and acaricidal effects on Tick (Hyalomma marginatum) of essential oils from two common Thymbra species

In this study, the fatty acid, essential oil and aroma composition of Thymbra sintenisii Bornm. & Aznav. subsp. sintenisii Bornm. & Aznav (TSS) and Thymbra sintenisii Bornm. & Azn. subsp. isaurica P.H.Davis (TSI) were determined by GC-MS. The cytotoxic activity was determined with MTT assay and antioxidant activities were determined with DPPH, ABTS, CUPRAC methods. Urease, acetyl, butyryl, angiotensin, α-amylase, tyrosinase, elastase, and collagenase enzyme inhibition activities of these species were also determined. The acaricidal effects of essential oils from aerial parts of TSS and TSI on ticks and the nanoparticle formation potential of their essential oils with AgNO3 were determined and compared. The main components of TSS essential oil and aroma were determined as carvacrol and o-cemen (66.78 and 35.44%, respectively), the major components of TSI essential oil and aroma were carvacrol and γ-terpinene (63.78 and 31.44%, respectively). The species exhibited remarkably high antioxidant activity, particularly in the ABTS and CUPRAC methods. It was also determined that the butyrylcholinesterase and acetylcholinesterase enzyme inhibition activities (Inhibition%: 76.12±0.83 and 74.13±0.33, respectively) of the species were quite high. Moderate antimicrobial activity against the bacteria was observed for both essential oils, with MIC values ranging from 312 to 1250 μg/mL. Moreover, essential oils of these species showed good acaricidal activity on Hyalomma marginatum (LC50: 11.82 μg/mL for TSS; LC50: 57.64 μg/mL for TSI). The high antioxidant, anticholinesterase, and acaracidal activities observed in both species are attributed to the presence of carvacrol in their essential oils. The species have potential to be used in food supplements-preservatives, pharmaceutical industry.

Effects of Inhaled Linalool on the Autonomic Nervous System in Awake Mice

Objective/background A previous study showed that geranium essential oil predominantly affects the parasympathetic nervous system. This article examined the effects on the autonomic nervous system of linalool, one of the main components of geranium essential oil. Methods Mice were placed on a narrow elevated open platform and pulse wave measurements were taken while they were awake, with behaviors restricted. Heart rate and heart rate variability were analyzed from the pulse waves obtained and the effects on the parasympathetic and sympathetic nerves were examined. Results The results showed that linalool (5 μL/L air, inhaled) resulted in parasympathetic dominance before and after administration. Conversely, a tendency toward sympathetic dominance was observed with fluoxetine (1 mg/kg, intraperitoneal) as the positive control in the elevated open-platform test. Conclusion These results suggest that linalool and essential oils containing linalool regulate the autonomic nervous system by promoting dominance of the parasympathetic nervous system.

Selenium content, chemical composition and volatile components of essential oil and hydrosol from flowers of Cardamine violifolia.

Cardamine violifolia is a unique selenium hyperaccumulating vegetable in China, but its flowers are commonly wasted in large-scale cultivation. To better utilize this resource, this study explored the selenium content, chemical composition, and volatile organic compounds (VOCs) of hydro-distilling essential oil (EO) and hydrosol from C. violifolia flowers. ICP-MS results indicated that the EO and hydrosol contained selenium reaching 13.66±2.82 mg/kg and 0.0084±0.0013 mg/kg, respectively. GC-MS analysis revealed that organic acids, hydrocarbons, and amines were the main components of EO. Additionally, benzyl nitrile, benzaldehyde, benzyl isothiocyanate, benzyl alcohol, megastigmatrienone, and 2-methoxy-4-vinylphenol also existed in considerable amounts. The hydrosol extract had fewer components, mainly amines. HS-SPME-GC-MS corresponded to the composition analysis and aromatic compounds were the prevalent VOCs, while HS-GC-IMS primarily identified C2-C10 molecular alcohols, aldehydes, ethers, and sulfur-containing compounds. This study first described the chemical composition and VOC profiles of EO and hydrosol from selenium hyperaccumulating plant.

Developmental Toxicity of C10 Massoia Lactone, the Main Constituent of Cryptocarya massoia, on Zebrafish (Danio rerio) Embryos

C10 massoia lactone (C10) is the main component of massoia essential oil derived from Cryptocarya massoia plant bark, which is used as natural flavoring agent of “generally recognized as safe” status. In this study, the developmental toxicity of C10 was evaluated on zebrafish (Danio rerio) embryos at an exposure level of 0–2000 µg·L−1, and acute toxicity was determined with respect to lethal effects, hatching rates, and morphological changes. Additionally, morphological changes were determined for the endpoints as the occurrence of yolk edema, pericardial edema, spine curvature, and shortened body length after treatment until 96 h post-fertilization (hpf). The complete lethality of C10 was achieved with embryos treated at 2000 µg·L−1, and most embryos treated at 1000 µg·L−1 developed pericardial edemas with some spine curvature. Some embryos exhibited delayed development with shortened body length when compared with the control. Hatchability was completely accomplished at the tested dose of 1000 µg·L−1, and cardiac malformation was observed using a transgenic zebrafish line Tg(cmlc:EGFP), with a lower heartbeat rate in embryos treated with C10 for 72 hpf. After 96 hpf, heartbeat rates were normalized when compared with the control group, and two cardiac development-related genes such as nppa and canca1 were differently expressed in C10-treated embryos by 2.3-fold and 0.4-fold, respectively. Therefore, C10 must be studied further in other higher organisms for its risk.

An Integrative Approach to Selected Species of Tanacetum L. (Asteraceae): Insights into Morphology and Phytochemistry.

In this work, we studied Tanacetum vulgare, Tanacetum parthenium, and Tanacetum corymbosum (Asteraceae) cultivated at the Ghirardi Botanic Garden (Toscolano Maderno, Brescia, Northern Italy) of the University of Milan. An integrative research approach was adopted: microscopic and histochemical, with special focus on the secretory structures responsible for the productivity of secondary metabolites; phytochemical, with the analysis of the essential oil (EO) profiles from the air-dried, flowered aerial parts collected in June 2021; bio-ecological, with emphasis, based on literature data, on the ecology and biological activity of the main EO components. In all three species, two basic trichome morphotypes (flagellar non-glandular and biseriate glandular) occurred with different distribution patterns. The glandular ones produced terpenes, along with flavonoids. A high level of chemical variability in the EO compositions emerged, specifically for qualitative data. T. vulgare profile was more complex and heterogeneous than those obtained from T. parthenium and T. corymbosum, with camphor as the predominant compound, followed by farnesol and α-santalone, respectively. Finally, the obtained scientific findings were made available to the visitors of the botanic garden through new dissemination labeling that highlights the "invisible", microscopic features of the plants, from an Open Science perspective ("Botanic Garden, factories of molecules…work in progress"-Lombardy Region Project Lr. 25/2016, year 2021).

Phytochemical Screening of Essential Oils and Ethanolic Extracts of Elsholtzia griffithii Fruits for Cosmeceutical Bioactivity

ABSTRACT The purpose of this study was to examine the chemical composition of essential oil and crude ethanolic extract from the fruits of Elsholtzia griffithii, and to evaluate their cosmeceutical bioactivities such as anti-acne, antioxidant, and anti-tyrosinase effects using in vitro experimental models. The main components of essential oils were neral (48.72%) and geranial (37.34%). Kaempferol, a dietary flavonoid, was found (0.45%) in crude ethanolic extract. The essential oil inhibited Propionibacterium acnes strongly, whereas the crude ethanolic extract demonstrated modest antibacterial action. The essential oil and crude ethanolic extract demonstrated antioxidant and anti-tyrosinase effects.

New insights into the chemical composition of Piper spp. collected in the northern region of Vietnam

Our study aimed to compare the essential oil composition of Piper species (Piperaceae) collected in the northern region of Vietnam and find possible fingerprints of different species. The aerial parts of seven Piper species including P. mutabile, P. leptostachyum, P. laosanum, P. boehmeriifolium, P. carnibracteum, P. albispicum, and P. longum were collected, shade-dried and chopped into small pieces before being submitted to the hydrodistillation of essential oils. The yields of essential oils ranged from 0.12 to 0.85%. GC-MS analysis of the essential oils led to the identification of 99 volatile components, accounting for 92.5–99.6% of the total oils. Sesquiterpenes (40.3–93.0%) were commanding in all essential oils while monoterpenes were only dominant in essential oils from P. albispicum (29.8%) and P. longum (29.4%). The distances between groups of seven Piper essential oils were measured using multivariate analysis. Elemene isomer seems to be the characteristic compound of all seven Piper essential oils. Besides, the essential oil from P. mutabile in the present study was characterized by the very high content of safrole (20.9%) while epi-γ-eudesmol (15.9%), cis-caryophyllene (14.4%), trans-caryophyllene (10.6%), guaiol acetate (10.1%), eremophilene (9.6%) were main components in essential oil from P. laosanum. Essential oil of P. boehmeriifolium was dominated by elemene isomer (15.6%), eremophilene (14.2%), and trans-caryophyllene (9.3%). Essential oil from P. albispicum in our study featured by high contents of eremophilene (11.1%) and β-pinene (10.1%). In the other hand, essential oil from P. carnibracteum was characterized by the dominant amount of trans-caryophyllene (21.7%), α-muurolene (21.1%), bicyclo[4.3.0]nonane,7-methylene-2,4,4-trimethyl-2-vinyl- (17.8%) while aromadendrene (25.7%), γ-cadinene (20.3%) were ascendant in essential oil from P. leptostachyum. To the best of our knowledge, this is the first time that the essential oil composition of P. leptostachyum and P. carnibracteum were investigated. Besides, the volatile components in the essential oils from P. albispicum, P. laosanum, and P. mutabile showed some differences in the comparison to the data published previously on the chemical composition of these aforesaid species which could depend on many factors.

Essential oil profiles, improvement of enzymatic and non-enzymatic antioxidant systems in different populations of Salvia subg. Perovskia by irrigation management

Salvia subg. Perovskia is an aromatic medicinal plant from the Lamiaceae family. Essential oil (EO) content and composition, along with enzymatic and non-enzymatic antioxidants, were evaluated in 18 plant populations under three levels of irrigation for two consecutive years. Based on the GC-MS analysis, the main components of EO were borneol (1.18–36.53%), followed by camphor (0.54–32.17%), 1,8-cineole (12.44–29.26%), δ-3-carene (0.39–21.20%), myrcene (0.59–16.28%), and α- pinene (0.79–12.87%) in the studied treatment. Except for malondialdehyde and hydrogen peroxide in leaves and roots, all the examined parameters showed lower values in the first harvest year compared to those of the second year. The activities of antioxidant enzymes, total phenolics, and flavonoids of the extracts were substantially enhanced as stress intensified to reach maximum values in leaves under severe stress and in roots under moderate stress conditions. The maximum root tanshinones content was observed under moderate water deficit conditions, while the highest EO content was obtained in plants exposed to severe stress conditions. Taking into account the evidence provided by this study, it can be inferred that the use of water deficit stress can serve as an effective method to stimulate and improve antioxidant properties, as well as the quantity and quality of secondary metabolites in Salvia subg. Perovskia.

Examination of the main chemical components of essential oil of Syzygium aromaticum as a corrosion inhibitor on the mild steel in 0.5 M HCl medium

The study delves into the versatile applications of essential oils, natural aromatic compounds derived from plants through hydro-distillation or cold extraction, across industries such as cosmetics, fragrances, food processing, traditional medicine, and agriculture. Notably, these plant-derived compounds have gained prominence as corrosion inhibitors for metals and alloys in acidic environments. The research focuses on evaluating the inhibitory capacity of Suzygium aromaticuim on regular steel submerged in an acidic medium, employing various concentrations of essential oil (1.5 g/L to 6 g/L). The inhibitory effectiveness was evaluated using electrochemical techniques, including potentiodynamic polarization curves and electrochemical impedance spectroscopy. Electrochemical measurements and optical microscope analyses were used to examine the effect of cloves' essential oils on the corrosion resistance of mild steel in a 0.5 M HCl media. NMR and IR spectroscopy were used to learn about the two isolated chemicals (eugenol and β-caryophyllene). The corrosion-inhibiting properties of β-caryophyllene at 2 g/L in an acidic media were studied. Density functional theory (DFT) computations and molecular dynamics simulations were used to isolate the essential oil component of cloves responsible for the corrosion inhibition of mild steel. Inhibition effectiveness peaked at 94 % at 4 g/L, leading the researchers to infer that the natural substance is a mixed-type inhibitor. Optical microscope analysis confirmed the protection offered at the optimum concentration, while β-caryophyllene demonstrated noteworthy inhibitor efficiency, especially when compared to Eugenol. DFT analysis further supported the corrosion inhibition potential of β-caryophyllene in aggressive solutions.

Diversity, distribution of the ginger family (Zingiberaceae) in West Sumatra based on herbarium specimens and its potency for genetic resources essential oil

Zingiberaceae is popular plant family that is widely used for medicinal purposes, as cooking spices, and as a source of essential oils. The Zingiberaceae family is characterized by its significant reliance on essential oils. This study aims to inventory, analyze distribution, and review the potential of essential oils from Zingiberaceae species. The species inventory is based on observations of herbarium specimens, and the potential of essential oils is known through a literature review. A total of 2,500 herbarium specimens stored at the Andalas University Herbarium (ANDA) and the Bogoriense Herbarium (BO) were identified. The results showed 100 species belonging to 20 genera of Zingiberaceae in West Sumatra. Zingiberaceae are found administratively in almost all cities and districts in West Sumatra, with Padang City and Mentawai Islands District. Geographically, Zingiberaceae are distributed in secondary and mixed forests in the lowland, medium elevation, and hilly to montane zones. Based on a literature review, 12% of Zingiberaceae species have been commercialized, 24% have potential for essential oil production, and the rest have not been studied for their essential oil content. The main components of essential oils found in Zingiberaceae are monoterpenes and sesquiterpenes.

Antimicrobial activity of limonene: Integrative review

Limonene is the main component of citrus essential oils, and can reach a concentration of up to 96%. Popularly known for its potential therapeutic effects on the body, among these we point out its broad antimicrobial activity against various types of pathogens. Therefore, the purpose of this study was to address the antimicrobial and antifungal properties of limonene compared to microorganisms of interest in dentistry, based on a bibliometric study and literature review. The following databases were analyzed: PubMed, Google Scholar, SciELO and Science Direct, from which ten articles published between 2011-2021 were selected. Most of results indicate a satisfactory antimicrobial potential, besides providing important data and perspectives regarding the indication and clinical use, in addition to innovative therapeutic modalities for diseases that affect the oral cavity, such as tooth decay, periodontal disease and candidosis.