Essential Oil Samples Research Articles

Essential oil from the stems of Croton kongensis Gagnep.: chemical composition, antimicrobial and anti-inflammatory activities

The current study describes the chemical compositions, antimicrobial and anti-inflammatory activities of the essential oil (EO) from the stems of Croton kongensis Gagnep., collected from two wild-growing populations in Thanh Hoa province, Vietnam, namely Nhu Xuan and Thuong Xuan. According to gas chromatography/mass spectrometry (GC/MS) analyses, the major components in the Nhu Xuan EO sample were (E)-caryophyllene (10.62%), bornyl acetate (9.81%), (E)-nerolidol (9.15%), and linalool (8.10%). In contrast, linalool (15.05%), bornyl acetate (9.52%), (E)-caryophyllene (7.91%), bicyclogermacrene (7.36%), 1,8-cineole (6.53%), and (E)-nerolidol (6.00%) were the dominant components in the Thuong Xuan EO sample. The two EO samples were screened for antimicrobial activity against a panel of pathogenic bacteria and fungi using a broth microdilution assay and showed promising antimicrobial activities with minimum inhibitory concentration (MIC) ≤ 200 μg/mL. Among them, the Nhu Xuan EO sample exhibited better activity against four bacteria and three fungi compared to the Thuong Xuan EO sample, which only showed activity against one bacterium and three fungi. Additionally, the anti-inflammatory study demonstrated that the EO samples from Nhu Xuan and Thuong Xuan inhibited nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells, with IC50 values of 105.71 ± 0.96 μg/mL and 94.93 ± 1.31 μg/mL, respectively. In conclusion, this is the first report describing the antimicrobial and anti-inflammatory effects of the EO from C. kongensis stems. Our results suggest that the EO from C. kongensis stems in both regions could be potentially utilized as new natural antimicrobial and anti-inflammatory ingredients in the medicine and food industries.

Evaluation of 60Co Irradiation on Volatile Components of Turmeric (Curcumae Longae Rhizoma) Volatile Oil with GC-IMS.

60Co irradiation is an efficient and rapid sterilization method. The aim of this work is to determine the changes in essential-oil composition under different irradiation intensities of 60Co and to select an appropriate irradiation dose with GC-IMS. Dosages of 0, 5, and 10 kGy of 60Co were used to analyze turmeric (Curcumae Longae Rhizoma) volatile oil after 60Co irradiation (named JH-1, JH-2, and JH-3). The odor fingerprints of volatile organic compounds in different turmeric volatile oil samples were constructed by headspace solid-phase microextraction and gas chromatography-ion mobility spectrometry (GC-IMS) after irradiation. The differences in odor fingerprints of volatile organic compounds (VOCs) were compared by principal component analysis (PCA). The results showed that 97 volatile components were detected in the volatile oil of Curcuma longa, and 64 components were identified by database retrieval. With the change in irradiation intensity, the volatile compounds in the three turmeric volatile oil samples were similar, but the peak intensity was significantly different, which was attributed to the change in compound composition and content caused by different irradiation doses. In addition, the principal component analysis showed that JH-2 and JH-3 were relatively correlated, while JH-1 and JH-3 were far from each other. In general, different doses of 60Co irradiation can affect the content of volatile substances in turmeric volatile oil. With the increase in irradiation dose, the peak area decreased, and so the irradiation dose of 5 kGy/min was better. It is shown that irradiation technology has good application prospects in the sterilization of foods with volatile components. However, we must pay attention to the changes in radiation dose and chemical composition.

Chemical composition and comparative analysis of lavender essential oil samples from Bulgaria in relation to the pharmacological effects

Lavender essential oil is economically important and widely used in aromatherapy perfumery, food industry and pharmacy. Bulgaria is a global leader in lavender cultivation overtaking countries such as France, UK, China, India, and Spain during the last few years. The aim of this research is: 1) to characterize a lavender essential oil sample obtained from agricultural plantation near Pomorie, Bulgaria; 2) to perform descriptive statistical test based on a data set of 13 samples available in 4 publications, 3) to compare the varieties regarding the quantity of the most important components such as linalool and linalyl acetate 4) to summarize the pharmacological effects of the main components. As a result of GS/MS analysis of the essential oil sample obtained from agricultural plantation near Pomorie, we identified 44 compounds. The major constituents were linalyl acetate (27.5%) linalool (24.1%),E-β-ocimene (7.0%), terpinen-4-ol (5.1%) caryophyllene (4.5%), carvacrol (4.4%), lavandulyl acetate (3.5%),Z-β-farnesene (3.3%), and -Z-β-ocimene (3.2%). Linalool and linalyl acetate are the main ingredients based on which the quality of the essential oil is evaluated. In the studied samples they fluctuated between varieties depending on the year of extraction and the locations of origin in Bulgaria. Some varieties were characterized by a more stable ratio of linalool – linalyl acetate, compared to others. The main other components of our sample as well as the other examined Bulgarian samples fit the standards according to the requirements of ISO (2002) and the of European Pharmacopoeia (10thedn., Council of Europe 2020) with few exceptions. Lavender oil has numerous pharmacological applications based on its anxiolytic, sedative, antioxidant, anti-inflammatory, antitumor and antimicrobial activities. Although linalool and linalyl acetate largely contribute to these effects, the overall efficacy of lavender oil is proven to be due synergistic relationships between the components.

Quality characteristics of white button mushrooms (Agaricus bisporus) affected by gamma irradiation and volatile oils during storage

Abstract Agaricus bisporus mushrooms contain various bioactive substances, the current study aimed to evaluate the effects of gamma-irradiation (1.5, and 2.0 kGy) and essential oils (EOs) fumigation treatments including; geranium (60, and 80 μL L−1) as well as lemongrass (40, and 60 μL L−1) on quality characteristics (color, weight loss, firmness), and microbial properties, as well as total and reducing sugars of mushrooms at 4 °C during storage for 12 days. It was found that 40 μL L−1 lemongrass (L1) showed the highest L* after 12 days of storage so, it gave the greatest impact on reducing browning of mushrooms. Geranium oil (G1) recorded the least increase in weight-loss (3.01 %) after 12 days of storage. Otherwise, the firmness was also significantly inceased in the EOs (60 μL L−1 of geranium and 40 μL L−1 of lemongrass) samples compared to the controls and gamma-rays. The EOs achieved slight increases in TSS% compared with other treatments. Also, total sugar content in all treatments showed an overall reduction with storage time. Gamma-irradiation (1.5, and 2.0 kGy) was more efficient in inhibiting the development of mesophilic and psychrophilic count. While, lemongrass treatment (L2) has the lowest count of fungi at the end of storage (0.5 log10 CFU g−1). The current findings suggest that and EOs (geranium & lemongrass) and gamma-irradiation are a promise process for maintaining the quality of A. bisporus through refrigeration preservation.

Chemical components of essential oils from aerial parts of Pycnanthemum virginianum and P. californicum (Lamiaceae) plants

Aim. The research is aimed at determining the qualitative and quantitative content of essential oils in the aerial part of two species of the genus Pycnanthemum Michx. (Lamiaceae) – P. virginianum (L.) T. Durand & B.D. Jacks. ex B.L. Rob & Fernald and P. californicum Norr. exDurand. The plants were introduced in the M. M. Gryshko National Botanical Garden of National Academy of Sciences of Ukraine (Forest-Steppe zone). These are representatives of the flora of North America, and they are little known in Ukraine. Plants have useful medicinal and nutritional properties, but the biochemical composition of their essential oils has not been sufficiently studied in the world.Materials and methods. In the experiment, the aerial herbal part of plants collected during the flowering phase was used. The quantitative content of the essential oil was determined by the hydrodistillation method, and its qualitative characteristics were found by the GC-MS analysis. The chromatographic profile was obtained on an Agilent Technologies 7890. The component composition of the essential oil was determined on a gas chromatograph with a HP 6890 mass spectrometric detector with a mass spectrometric detector 5973. We used a mass spectrometric detector 1.6 – 800 a.o.m., EI ionization, SIM & Scan mode, “Hewlett Packard”, USA. Identification of essential oil components was performed using the NIST mass spectrum library in combination with AMDIS content-time identification programs.Results and discussion. P. virginianum was found to produce 1.96 ± 0.17 % of essential oil, in which 12 compounds out of 13 were identified; P. californicum had 2.66 ± 0.13 % of essential oil, 13 compounds out of 15 were identified. The essential oil samples obtained have pulegone as the dominant component: P. virginianum – 44.65 %, P. californicum – 86.07 %. In addition to it, they also contain thymol, myrcene, 1.8-cineole, menthone, limonene and other compounds.Conclusions. For the first time, the qualitative and quantitative composition of the essential oils of plants of P. virginianum and P. californicum species introduced in Ukraine has been determined. The results obtained indicate that when introduced plants have a high biosynthesizing ability to produce essential oil. Pulegone has been found to be the dominant component; therefore, the essential oil can be classified as a pulegone-type essential oil. We believe that the raw material of P. virginianum and P. californicum are potentially suitable for use in perfumery, cosmetics, aromatherapy, personal care products, dentistry, and in the pharmaceutical and food industries.

Comparative Analysis of Quality of Essential Oil of Wormwood Herb Synanthropic Flora of Voronezh Region

Introduction. The formation and accumulation of biologically active substances in plants is a complex process associated with a number of environmental factors, including anthropogenic ones. The study of the characteristics of the qualitative composition of essential oil of wormwood grass of bitter different from the ecological point of view of the places of harvesting is relevant.Aim. The aim of this study study of the qualitative composition of essential oil of bitter wormwood grass, harvested in areas of the Voronezh region that are different from an ecological point of view.Materials and methods. In the Voronezh region, 4 points of raw materials procurement were selected, diverse in terms of anthropogenic impact. Isolation of essential oil from the raw materials was carried out according to the method of PS "Wormwood of bitter grass". Component composition of the obtained essential oils was determined using Agilent 7890B GC System (Agilent Technologies, USA) with Agilent 5977A MSD mass selective detector (Agilent Technologies, USA). Data analysis and processing was carried out on the basis of NIST11 databases (from 19.05.2011), MassHunter ver. B.06.00 and NIST MS Search ver. 2.0 software were used.Results and discussion. In a sample of essential oil obtained from reserved raw materials, monoterpene compounds account for more than 82 %, and sesquiterpene compounds – 16.6 %, about 2 % are organic impurities. Intensive biosynthesis of monoterpenes was noted in a sample collected in the area of agricultural fields of the Verkhnekhavsky district, its mass fraction is more than 73 %. In samples of raw materials with anthropogenic load (OJSC "Minudobreniya" and Highway M4), the share of monoterpene compounds is significantly lower (63.7 and 49 %, respectively). The increase in the proportion of sesquiterpene compounds in the last samples of wormwood essential oil may be due to the excessive acidity of the urbanized places of the workpiece. The sesquiterpene compound hamazulene, which stains essential oil blue, is identified in only two samples of gorse grass wormwood harvested along agricultural fields and in M4 tracks, which explains the presence of a blue hue in these oils.Conclusion. The chromato-mass spectrometric analysis of the essential oil of the studied samples of bitter wormwood grass made it possible to identify more than 70 different components in them, while the qualitative composition of the essential oil of the raw materials of different places of the workpiece was significantly different, which may indicate a significant influence of the place of growth of the species and anthropogenic factors on the features of the secondary metabolism of terpene compounds in the plant organism.

Integrated Analysis by GC/MS and 13C NMR of Moroccan Cladanthus mixtus Essential Oil; Identification of Uncommon Epoxyfarnesanes

Cladanthus mixtus (L.) Chevall., Asteraceae, also known as Moroccan chamomile, is a spontaneous, annual plant growing wild in North-Western Morocco. Economically, the essential oil of C. mixtus is of high interest, Morocco being the only supplier on the international market. Two essential oil samples (EO) were isolated from aerial parts of Cladanthus mixtus (L.) Chevall., and analyzed by a combination of chromatographic and spectroscopic techniques (gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC/MS), and 13C NMR spectroscopy). Computer matching against the in-house 13C NMR library allowed the identification of the eight components at appreciable contents, namely 3,6,6,9-bis-epoxy-farnesa-1,7(14),10-triene, and its 3-epi, 9-epi, and 3,9-diepi epimers, and 6,9-epoxy-farnesa-1,7(14),10-trien-3-ol and its 3-epi, 6-epi, and 3,6-diepi epimers. Our results confirm the tremendous chemical variability of Moroccan C. mixtus essential oil and the usefulness of 13C NMR analysis, in combination with GC(RI), for the identification of uncommon oxygenated sesquiterpenes that induce an original composition.

Lipase-catalysed changes in essential oils revealed by comprehensive two-dimensional gas chromatography

Candida antarctica lipase A (CALA) was applied for the chemo-selective enzymatic transesterification of terpene and phenyl alcohols in 35 different essential oil samples. Comprehensive two-dimensional gas chromatography with mass spectrometry (GC×GC‒MS) analysis enabled the separation and tentative identification of a cohort of 125 compounds, allowing the instant visualisation of the reaction process changes, amid the complex chemical background of the samples. The results indicate that 42 out of 79 alcohols so-identified were fully or partially esterified within 48 h of reaction, with primary alcohols being the substrates of preference of the enzyme (90–100% conversion), followed by secondary alcohols (mostly ~ 80–100% conversion). No significant conversion of tertiary alcohols and phenols was observed using the tested conditions. Overall, the enzyme’s performance was consistent for primary alcohol substrates identified in multiple samples of different compositions. The observed selectivity, efficiency, robustness, scalability (enzyme/substrate working concentration ratio > 1:160), potential reusability, mild reaction conditions, and other factors make this process a greener and more sustainable alternative for industry applications, particularly for the manufacture of novel flavours and fragrances.Graphical

Extinction Risk Assessment and Chemical Composition of Aerial Parts Essential Oils from Two Endangered Endemic Malagasy Salvia Species.

Seven essential oil samples of two endemic species of Malagasy sage, Salvia sessilifolia Baker and Salvia leucodermis Baker, were investigated via GC(RI), GC-MS and 13C NMR spectrometry. In total, 81compounds were identified accounting for 93.5% to 98.7% of the total composition. The main constituents for the both species were (E)-β-caryophyllene (29.2% to 60.1%), myrcene (1.2% to 21.7%), α-humulene (5.2% to 19.7%), (E)-nerolidol (0.8% to 15.5%) and caryophyllene oxide (1.4% to 10.8%). Ethnobotanical survey of 46 informants revealed that decoctions of leafy twigs and chewed leaves were usually used. Due to the repeated fires, over-harvesting and grazing, the populations of S. sessilifolia and S. leucodermis are drastically fragmented. These risk factors led to threats to the habitats of the target species. Salvia sessilifolia Baker and Salvia leucodermis Baker are proposed to be classified as endangered species.

The Impact of Environmental Stress on the Secondary Metabolites and the Chemical Compositions of the Essential Oils from Some Medicinal Plants Used as Food Supplements

This study aims to study the impact of environmental stresses on the chemical compositions of essential oils and the content of secondary metabolites of the plants most used by the rural population: Thymus vulgaris, Mentha pulégium and Rosmarinus officinalis. The results of the study indicate that the percentage of secondary metabolites increased in the second year when temperature and water pressure increased by 50%. Specifically, coumarin increased from 3.94% to 9.23%, saponins increased from 6.17% to 7.78%, tannins increased from 2.90% to 6.12%, alkaloids increased from 6.72% to 15.95%, and flavonoids increased from 7.42% to 12.90%. However, in the fourth year, the temperature continued to increase, and water availability decreased by 75%, leading to a decrease in the rate of secondary metabolites. Coumarin decreased from 9.22% to 6.15%, saponin decreased from 7.80% to 6.79%, tannin decreased from 6.11% to 4.16%, alkaloids decreased from 15.95% to 10.45%, and flavonoids decreased from 12.90% to 9.70%. Similar results were observed for the essential oil yield, which increased in year two from 3.57% to 3.84% and decreased in year four to 1.04%. The same pattern was observed for Mentha pulégium and Rosmarinus officinalis. The gas chromatography analysis of the three essential oil samples showed that the majority of the compounds of the three plants were modified under the conditions of climate change. For Mentha pulégium, pulegone was found to represent the highest proportion in sample two (73.3%), followed by sample one (71.1%), and finally, sample three (61.8%). For Rosmarinus officinalis, the majority of compounds were cineole and camphor, with cineole representing 36% in sample two, 45.89% in sample one, and 43.08% in sample three, and camphor representing 21.44% in sample two, 21.56% in sample three, and 17.44% in sample one. For Thymus vulgaris, the majority of the compounds were Thymol and Carvacrol, which underwent approximately the same modifications as the majority of compounds in the other two plants. The results indicate that environmental stresses can lead to significant changes in these compounds, which can affect the medicinal and aromatic properties of these plants. The findings of this study highlight the need for more research to understand the impacts of climate change on plant species and the potential implications for human health and well-being.

Terpenoid composition and antibacterial assay of whole aerial parts and roots of Plectranthus striatus Wight ex Hook. f.

Terpenoid composition and antibacterial assay of whole aerial parts and roots of <i>Plectranthus striatus</i> Wight ex Hook. f.

Chemical composition and biological activities of essential oils from the flowers and leaves of Celtis planchoniana K.I.Chr.

Most plant parts are used in traditional food and medicine. Plants are significant resources of potential phytochemicals. This study investigated the properties of essential oil, antioxidant, and antimicrobial activities of the flowers and leaves of the Celtis planchoniana plant. Based on the GC/MS-FID analysis of essential oils extracted from the flowers and leaves of C. planchoniana, 101 and 91 compounds were identified from their structures, respectively. Chemical classes with the highest percentage of compounds found in essential oils of plants were oil acids, with 31.51% in flowers, and aldehydes, with 32.89% in leaves. Hexadecanoic acid (29.94%) and (E)-2-hexenal (16.11%) compounds were determined as the main components in the plant’s flowers and leaves. Among the flower and leaf samples, the highest antioxidant levels were 132.77-80.10 mg AA eq./100 mL in TAC, 17.63-118.23 mg AA eq./100 mL in ABTS, 71.41-85.15 mg GA eq./100 mL in TPC, and 15.08-15.71 mg AA eq./100 mL in DPPH capacity. According to the TFC, TPC, ABTS, DPPH, and FRAP tests conducted to determine the antioxidant properties of C. planchoniana, the essential oil obtained from its leaves demonstrated more significant antioxidant properties than the essential oil obtained from its flowers. According to the antimicrobial activity analysis, the leaf and flower essential oil samples exhibited no antimicrobial activity against the microorganisms tested.

Chemical constituents and biological activities of the seed essential oil from Michelia tonkinensis grown in Thanh Hoa province, Viet Nam

AbstractEssential oils (EOs) from the seed of Michelia tonkinensis were extracted in four ways hydrodistillation (HD), microwave‐assisted hydrodistillation (MHD), ultrasound‐assisted hydrodistillation (UHD) and enzyme‐assisted hydrodistillation (EHD). The chemical constituents of these EOs were analysed by gas chromatography (GC‐FID) and gas chromatography/mass spectrometry (GC/MS). Phenylpropanoids were the main components in which safrole is the dominant constituent (82.98‐91.53%), followed by monoterpene hydrocarbons (5.26‐11.94%). In comparison with traditional hydrodistillation method (HD only), the EOs obtained from the MHD, UHD and EHD methods have the higher safrole contents (91.32%, 90.96% and 90.25%, respectively). The essential oils were also tested for their antioxidant, anti‐imflammatory, antimicrobial and cytotoxic activities. The HD essential oil sample showed inhibitory activity against 6/8 tested microorganisms, i.e., Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtillis, Candida albicans, and Saccharomyces cerevisiae. The MHD and EHD exhibited the inhibitory activity against three strains E. coli, A. niger and F. oxysporum. The UHD inhibited E. coli and F. oxysporum.

Influence of Season and Habitat on the Essential Oils Composition, Allelopathy, and Antioxidant Activities of Artemisia monosperma Delile

Plants belonging to the Artemisia genus (Asteraceae) are widely distributed worldwide and have many ethnopharmacological, traditional, therapeutic, and phytochemical aspects. Artemisia monosperma is an important aromatic plant due to its traditional and therapeutic uses and phytochemical diversity, including essential oils (EOs). The EO chemical profile of aromatic plants has been reported to be affected by exogenous and endogenous factors. Geographic and seasonal variations are crucial factors shaping the chemical composition of the EO. Herein, the variations of the yields, chemical profiles, and allelopathic and antioxidant activities of A. monosperma EOs collected from three regions in four seasons were assessed. A slight variation in the oil yields was observed among regions and seasons, while the chemical profile, characterized via GC-MS, exhibited significant quantitative and qualitative variation among either regions or seasons. Sesquiterpenes were the main components of all EOs, with significant variation in concentration. In most EO samples, the summer-plant samples had the highest concentration of sesquiterpenes, followed by spring, winter, and autumn. The 7-epi-trans-sesquisabinene hydrate, 6-epi-shyobunol, dehydro-cyclolongifolene oxide, isoshyobunone, diepicedrene-1-oxide, dehydro-aromadendrene, and junipene were the main compounds of all the EO samples. The extracted EOs of the A. monosperma samples showed considerable allelopathic activity against the weed Dactyloctenium aegyptium and the crop Lactuca sativa. A significant variation in allelopathic activity was observed among samples collected during different seasons, while the samples of the autumn and summer seasons had more potential. Also, L. sativa was more affected by the EO compared to D. aegyptium, reflecting that weeds are more resistant to allelochemicals. In this context, the EOs of A. monosperma samples exhibited substantial antioxidant activity with the same pattern of allelopathic activity, whereas the samples of the autumn and summer seasons showed higher antioxidant activity. These biological activities of the EOs could be ascribed to the higher content of oxygenated compounds. The present study revealed that seasons have a substantial effect on EO production as well as composition. In consequence, the biological activities varied with the variation of the chemical profile of the EO. These results show the importance of season/timing for sampling aromatic plants.

Study of the Component Composition of Essential Oil, Morphology, Anatomy and Ploidy Level of Hyssopus officinalis f. cyaneus Alef

Common hyssop (Hyssopus officinalis L.) is widely used as an aromatic and medicinal plant. In the component composition of the essential oil from the above-ground mass of H. officinalis f. cyaneus, from the collection of the Nikita Botanical Garden, the bicyclic monoterpene ketones isopinocamphone (50.99–64.41%) and pinocamphone (3.95–18.88%) predominate, which allows us to attribute this form to the isopinocamphone chemotype for use in pharmacology. An essential oil sample with a high content of isopinocamphone (70.74%) in complete absence of pinocamphone was determined, which made it possible to use the plant as a starting material for breeding. The objective of our work was to study the component composition of the essential oil of this form, and the morphology, anatomy and ploidy level of microshoots in vitro on a nutrient medium with BAP. This was compared with ex situ samples to develop a cultivation technique with the preservation of a valuable trait for use in task-oriented selection. Biotechnological methods are used for future mass propagation, study and the preservation of breeding forms. Morphological and anatomical features and ploidy of H. officinalis microshoots were studied in vitro. Using in vitro culturing of microshoots on MS medium containing BAP, a decrease in the cuticular layer and the degree of development of collenchyma near vascular bundles in leaves were shown compared to microshoots ex situ. Significant structural changes were found with a high increase in BAP concentration, while no changes in the ploidy level were detected.

Absorption of essential oils in Laponite: Stability enhancement and structural characteristics

The suitability of Laponite (Lap) for essential oils (EO) capture is investigated in this work by directly mixing both components (Lap–EO samples). This simple and green approach avoids the use of solvents and heat, which would otherwise compromise the EO's physical-chemical properties. Lavender, tea tree, and rosemary oils were used for this purpose, and the samples were produced with an initial 1:2 mass ratio of Lap to EO. Thermal stability of EO and absorption efficiency of Lap–EO composites were determined using thermogravimetric analysis (TGA), revealing a rapid degradation of the pure EO which was significantly diminished when molecules were incorporated into the Lap matrix. The EO absorption was quantified, and the results showed that all the samples had absorptions greater than 240 mg∙g−1. X-ray diffraction (XRD), scanning electron microscopy (SEM), and small- and wide-angle X-ray scattering (SAXS/WAXS) experiments were carried out in order to study the structure formed by the Lap–EO composites. The results showed an increase in the Lap interlayer d-spacing, indicating that molecules were successfully intercalated, conserving Lap's structure integrity, and forming larger grain aggregates. Even further, SAXS/WAXS data allowed for the determination of the specific surface area and porosity, important parameters for characterizing porous materials. For Lap−EO samples, there was a 160% increase in surface area and a 120% increase in porosity; this information allowed for the development of a geometric model of the Lap layers, in good agreement with experimental data.

Phytochemical Analysis of the Essential Oils From the Rhizomes of Three Vietnamese Curcuma Species and Their Antimicrobial Activity

Objective/Background The essential oils (EOs) of Curcuma species contain various volatile compounds with bioactivity. However, the phytochemical profile of Curcuma thorelii and the antimicrobial activities of Curcuma rhabdota, and Curcuma petiolata have received limited attention. This study aims to characterize and compare the major compounds and the antimicrobial activities of EOs extracted from the rhizomes of C. rhabdota, C. thorelii, and C. petiolata collected in Vietnam . Methods EOs were obtained by hydrodistillation of the rhizomes of three Curcuma species. The chemical profiles were determined using gas chromatography-mass spectrometry (GC-MS). The antimicrobial activities against bacteria and a pathogenic fungus were determined through the broth dilution method. Results The volatile profiles of C. rhabdota, C. thorelii, and C. petiolata EOs included 63 (97.1%), 47 (98.0%), and 50 (95.6%) compounds, respectively. The major compound in the EO of C. rhabdota rhizomes was 3-carene (16.6%), followed by camphene (9.8%), α-copaene (7.4%), γ-terpinene (7.3%), camphor (5.9%), and β-curcumene (5.7%). The predominant compounds of the EO extracted from C. thorelii rhizome were xanthorrhizol (40.7%), β-curcumene (20.7%), and α-curcumene (8.9%), while camphene (17.0%), ( E)- β-elemenone (16.8%), (E)-β-farnesene (13.6%), germacrone (8.9%), 1,8-cineole (7.2%), and camphor (6.0%) were the most abundant components in C. petiolata rhizomes. Except for Pseudomonas aeruginosa, which was less susceptible to the EOs with a minimum inhibitory concentration (MIC) value of 128 μg/mL, the three oil samples exhibited potent antimicrobial activities against all investigated strains with MIC values in the range of 2-32 μg/mL. Especially, the EO of C. thorelii rhizomes showed intense activity against Enterococcus faecalis, Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Candida albicans with a MIC value of 2 µg/mL. Conclusion The results showed the chemical variability of EOs from three Curcuma species and the prepared EO samples showed potent antimicrobial activities against several microbial strains, indicating a high potential application as a food preservative and in the pharmaceutical industry.

Yield and Composition of the Essential Oil of the Opopanax Genus in Turkey

The genus Opopanax W. Koch (Apiaceae) is represented by four species in Turkey. The composition of the essential oil of Opopanax genus members (Apiaceae) growing in Turkey was investigated in this study. GC-MS was used to analyze the composition of Opopanax essential oil samples that were taken from their natural environments. The Clevenger apparatus was used to hydrodistill the plant's aerial parts, and the yields were determined to be between 0.2% v/w (for O. siifolius) and 0.4% (for O. hispidus, O. chironium, and O. persicus). The results and the chemical data provided some information and clues on the chemotaxonomy of the genus Opopanax. In this study, γ-elemene, butanoic acid octyl ester, and cylopropane were the main compounds identified in the essential oils of O. chironium, O. hispidus, and O. persicus. In particular, hexynyl n-valerate was most abundant in the essential oil of O. chironium, cyclopropane in that of O. hispidus, γ-elemene in that of O. persicus, and n-hexadecanoic acid/palmitic acid in that of O. siifolius. In a chemotaxonomic approach, the essential oil analysis of the Opopanax species revealed that these species conformed in a cluster analysis with their morphological classification. The constituents of the essential oils of all examined in the genus Opopanax were determined in this study, which is the most thorough one to date. This study provides new information about the composition of the essential oils of the investigated species.

Chemical Composition of Essential Oils Obtained from Abies taxa in Türkiye and Investigation of Antimicrobial Activities

Aim of study: The aim of this study is to reveal the biochemical component and antimicrobial effects of essential oils obtained from different parts of Abies taxa in Türkiye. Material and methods: Essential oils were analyzed for their antibacterial and antifungal activities by using Steam Distillation Method and MIC test against nineteen microorganisms, In the wells where the effect was observed according to the MIC test, the MBC test was performed to determine that the effect was bactericidal or inhibitory (bacteriostatic). For determination of chemical composition; samples of essential oils obtained from plants with Hydrodistillation were analyzed with GC MS QP 2010 Ultra (Shimadzu). Main results: Beta-pinene, cis-Ocimene and Beta-Phellandrene were found to be the main components in all parts of the taxon when looking at the chemical compounds of A. cilicica subsp. isaurica taxon. There are differences in essential oil components in the branches and leaves of A. nordmanniana subsp. nordmanniana and A. cilicica subsp. cilicica taxa in the main components. Highlights: The results of the study reveal that the oils obtained from the leaves, branches and cones of Abies taxa can be used as a supportive health product and for medical purposes with additional studies.

Changes in the essential oil content and composition of pelargonium graveolens l’hér with different drying methods

In this study, the effect of various drying methods (fresh plant, shade-drying, sun-drying, and oven-drying at 30 and 60 °C) on the essential oil (EO) composition of rose-scented geranium were determined. Essential oil samples were extracted by hydrodistillation and analyzed by GC and GC-MS systems. The highest EO contents were obtained in the fresh plant (1.98%), followed by shade-drying (1.34 %) and oven-drying at 30 °C (1.20 %). The main components were citronellol (23.99-39.87%), geraniol (4.15-17.09%), menthone (4.48-8.34%), linalool (1.96-7.42%), β-caryophyllene (2.63-4.32%), geranyl tiglate (0.99-4.52%), citronellyl butyrate (0.53-5.31%) and cis-rose oxide (0.71-3.15%). The drying methods showed a marked impact on the constituents of the EO samples. The results demonstrated that drying the aerial parts of fresh geranium, and shade-drying and oven-drying at 30 °C were the best optimal methods to obtain the highest oil yield, and citronellol, geraniol, and linalool contents in the oil.