Search Results (17)

Bluehead gilia or bluefield gilia (Gilia capitata Sims, Polemoniaceae) is an annual herbaceous plant widely distributed in the western regions of North America but cultivated as an ornamental flower in various regions to support pollinators. The comprehensive chemical composition of this plant has not been previously reported. Essential oils (EOs) were obtained by hydrodistillation from different parts of the gilia plants. The yield of EOs ranged from 0.42 to 1.97 mL/kg, with the largest yields being obtained from the seeds; smaller yields obtained from the flowers, fruits, and leaves; and the lowest quantity obtained from the stems, roots, and shells. Using the GC-MS method, we identified 116 compounds. Hexahydrofarnesyl acetone was dominant in most parts of the G. capitata. The EO of flowers was dominated by hexahydrofarnesyl acetone (19.1%), fruits by hexahydrofarnesyl acetone (18.2%), seeds by hexahydrofarnesyl acetone (15.2%), fruit by (+)-epi-bicyclosesquiphellandrene (15.4%), leaves by phytol (23.3%), stems by isomanool (8.3%), and roots by (-)-myrtenol (25.7%). Triterpenoid saponins were identified, and 21 compounds were quantified (by HPLC). Saponin levels were high in aerial parts (excluding stems) and the lowest in plant roots. Based on the contents of EO and saponins, the aerial parts of G. capitata may have pharmaceutical properties, but saponins might be the main value of G. capitata. Full article

The key objective of this study was to determine the yield and chemical composition of eight commercial samples and one collected sample of common vervain (Verbena officinalis L.) herb essential oil (EO) originating from seven different countries, and subsequently, to assess its potential for treating anxiety and depression. According to GC-MS analysis, 90 compounds were identified, 49 of which were discovered for the first time in V. officinalis EO. The plants with the highest oil content are from Greece (4.7 mL/kg) and South Carolina, USA (5.2 mL/kg). The chemical markers for the studied chemotypes of EO of V. officinalis are the terpenoids o-cymene, p-cymene, L-carvone, thymol, carvacrol, α-curcumin, hexahydrofarnesyl acetone, phytol, (E)-β-ionone, and phenylpropene anethole. The chemotype from the UK demonstrated the greatest affinity to the continuum under study; it has the highest levels of similarity—85.2% with the chemotype from Greece, 69.4% with the chemotype from the USA, 68.2% with the chemotype from Estonia (2), 58.7% with the chemotype from Germany, and 58.6% with the chemotype from Hungary. The chemotypes identified have the potential for use in the treatment of anxiety and depression. Full article

Essential oils (EOs) are advised by traditional medical systems for the treatment of a variety of disorders worldwide. In many ancient medical systems around the world, Polygonum herbs have been employed as remedies including P. equisetiforme Sm. The EO profile of P. equisetiforme and its bioactivities have yet to be discussed in depth. As a result, the current study aims to investigate the chemical profile and free radical scavenging capacity of P. equisetiforme EO. Hydrodistillation was used to obtain the EO from P. equisetiforme, and gas chromatography–mass spectrometry (GC-MS) was used for analysis. A total of forty-three compounds, including terpenes and sesquiterpenes as the main components (76.13% and 69.06%, respectively), were identified in the oil using the GC-MS analysis. The main constituents of the oil were hexahydrofarnesyl acetone (29.45%), 7-epi-selinene (14.45%), isospathulenol (8.35%), and n-docosane (6.79%). The chemosystematic significance of the plant was established via multivariate assessing, comprising principal component analysis (PCA), hierarchical clustering, and constellation plot, of the EO principal components of the various Polygonum plants. The P. equisetiforme exhibited different associations with the studied Polygonum spp. Then, the scavenging of the free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) was used to evaluate the radical scavenging abilities of EO compared with those of vitamin C, a reference antioxidant. P. equisetiforme EO exhibited the scavenging capacity of the DPPH and the ABTS free radical with respective IC₅₀ values of 470.01 and 113.74 mg L⁻¹ compared with vitamin C, and with IC₅₀ values of 39.06 and 26.09 mg L⁻¹, respectively. The in silico studies revealed that the oxygenated sesquiterpenes, especially ar-turmerone, hexahydrofarnesyl acetone, and 5E,9E-farnesyl acetone, exhibited the best fitting with hematopoietic cell kinase (Hck) and human Peroxiredoxin 5 proteins with ΔG values of −6.14 and −4.93, −6.83 and −5.34, and −7.08 and −5.47 kcal/mol, respectively. The major components’ combined or individual effects may be responsible for the antioxidant properties. Therefore, additional extensive studies are advised to characterize the essential compounds as radical scavenger agents, either individually or in combination. Full article

(1) Background: The purpose of this study was to compare the free volatile compounds of 18 Veronica species (Plantaginaceae), as previously analyzed by gas chromatography coupled with mass spectrometry, with their DNA sequences for internal transcribed spacers ITS2 and ITS1-5.8S-ITS2 of the nuclear ribosomal DNA. (2) Methods: Two sets of DNA sequence data were generated and used for phylogenetic analysis: ITS2 sequences (~360 bp) obtained by next-generation sequencing and ITS1-5.8S-ITS2 sequences (~580 bp) sequenced by the Sanger sequencing method. Clustering from previously analyzed free volatile compounds was performed by Ward’s method. (3) Results: Both sets of DNA sequence data showed that the 18 analyzed Veronica species were grouped into eight main groups corresponding to the following subgenera: Pentasepalae, Pocilla, Chamaedrys, Veronica, Beccabunga, Cochlidiosperma, Stenocarpon and Pseudolysimachium. Results of the clustering analysis of free volatile compounds showed better clustering when using microwave-extracted volatiles. Three clusters were detected with the following main compounds: hexahydrofarnesyl acetone, hexadecanoic acid, phytol, caryophyllene oxide and (E)-caryophyllene. (4) Conclusion: The phylogenetic analysis of ITS2 data obtained by NGS technology and ITS1-5.8S-ITS2 data obtained by Sanger sequencing resulted in the grouping of 18 Veronica species into eight subgenera, which is in accordance with the existing classification. Statistical testing showed that there was no correlation between such clustering of Veronica species and clustering that was based on free volatile compounds. The achieved results can be viewed in the light of parallel evolution among some of the species of the Veronica genus as well as the fact that volatile compound composition can be influenced by environmental factors or epigenetic modifications. Full article

Supercritical carbon dioxide extraction was used for the extraction of Parrotia persica yellow and amber leaves. The lipophilic phytochemicals present in the analyzed leaves were as follows: neophytadiene, hexahydrofarnesyl acetone, octadecanal, 1-octadecanol, phytol, squalene and α-tocopherol. α-cadinol was present in yellow and β-sitosterol in amber leaves. The Box–Behnken design was used for the optimization of pressure, temperature and CO₂ flow rate and response surface methodology for the total extraction yield and α-tocopherol relative amount. The total extraction yield was 1.62% for yellow and 1.52% for amber leaves. The α-tocopherol relative amount was 80.03 mg per 100 g of dry plant material for yellow leaves and 315.30 mg per 100 g of dry plant material for amber leaves. The effects of temperature and CO₂ flow rate were found to have a significant influence on the total extraction yield for both plant materials analyzed. The effects of pressure and temperature significantly influenced the α-tocopherol relative amount in both plant materials used. The optimum extraction conditions for the total extraction yield were 30 MPa, 40 °C and 3 kg·h⁻¹ CO₂ flow rate for both plant samples. In the case of the α-tocopherol relative amount, the optimum temperature was 40 °C, while the pressure and CO₂ flow rate were slightly different. The predicted values matched well with the experimental values for the total extraction yield and α-tocopherol relative amount in all plant materials used for the experiment. Full article

Free volatile compounds were isolated from 21 Croatian Veronica species studied by hydrodistillation (HD) and microwave extraction (ME) and analyzed by gas chromatography coupled with mass spectrometry. Principal Component Analysis (PCA) distinguished some clusters based on the relative proportion of major compounds, such as hexadecanoic acid, hexahydrofarnesyl acetone, phytol, E-caryophyllene, and caryophyllene oxide, which were identified in all species studied by both isolation methods. In addition to these compounds, germacrene D, δ-selinene, and eicosane were also identified in five samples from dry habitats isolated using ME. Allo-aromadendrene and β-ionone are particularly abundant in five species from wet habitats isolated by both methods. The peculiarities of Veronica species from moderate habitats isolated with HD are benzene acetaldehyde, n-nonanal, and the identification of significant compounds from the hydrocarbon class, while the peculiarity of ME is (E)-β-damascenone. In this article, we present new results on the phytochemical characterization of Veronica species from different habitats. The biological potential of these compounds should be further investigated for a better understanding and utilization of the specialized plant metabolites. Full article

The exploration of new bioactive compounds from natural resources as alternatives to synthetic chemicals has recently attracted the attention of scientists and researchers. To our knowledge, the essential oil (EO) of Kickxia aegyptiaca has not yet been explored. Thus, the present study was designed to explore the EO chemical profile of K. aegyptiaca for the first time, as well as evaluate its antioxidant and antibacterial activities, particularly the extracts of this plant that have been reported to possess various biological activities. The EO was extracted from the aerial parts via hydrodistillation and then characterized by gas chromatography-mass spectrometry (GC-MS). The extracted EO was tested for its antioxidant activity via the reduction in the free radicals, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). In addition, the EO was tested as an antibacterial mediator against eight Gram-negative and Gram-positive bacterial isolates. Forty-three compounds were identified in the EO of K. aegyptiaca, with a predominance of terpenoids (75.46%). Oxygenated compounds were the main class, with oxygenated sesquiterpenes attaining 40.42% of the EO total mass, while the oxygenated monoterpenes comprised 29.82%. The major compounds were cuminic aldehyde (21.99%), caryophyllene oxide (17.34%), hexahydrofarnesyl acetone (11.74%), ar-turmerone (8.51%), aromadendrene oxide (3.74%), and humulene epoxide (2.70%). According to the IC₅₀ data, the K. aegyptiaca EO revealed considerable antioxidant activity, with IC₅₀ values of 30.48 mg L⁻¹ and 35.01 mg L⁻¹ for DPPH and ABTS, respectively. In addition, the EO of K. aegyptiaca showed more substantial antibacterial activity against Gram-positive bacterial isolates compared to Gram-negative. Based on the minimum inhibitory concentration (MIC), the EO showed the highest activity against Escherichia coli and Bacillus cereus, with an MIC value of 0.031 mg mL⁻¹. The present study showed, for the first time, that the EO of K. aegyptiaca has more oxygenated compounds with substantial antioxidant and antibacterial activities. This activity could be attributed to the effect of the main compounds, either singular or synergistic. Thus, further studies are recommended to characterize the major compounds, either alone or in combination as antioxidants or antimicrobial agents, and evaluate their biosafety. Full article

The composition of free volatile compounds of essential oils (EO) and hydrosols (Hy) from four different localities of the species Veronica austriaca ssp. jacquinii (Baumg.) Eb. Fisch. were analyzed by gas chromatography coupled with mass spectrometry. In the EOs, the most abundant compounds identified were hexahydrofarnesyl acetone (23.34–52.56%), hexadecanoic acid (palmitic acid, 26.71–58.91%) and octadecanol acetate (0–6.24%). The hydrosols were characterized by high abundance of methyl eugenol (23.35–57.93%), trans-p-mentha-1(7),8-dien-2-ol (5.24–7.69%) and thymol (3.48–9.45%). Glandular trichomes were analyzed using SEM (Scanning Electron Microscopy), as they are the sites of synthesis of free volatile compounds. We have detected glandular trichomes, consisting of a one stalk cell and two elliptically shaped head cells, and non-glandular (unbranched, bi-cellular to multicellular) trichomes on stems, leaves and the sepals. Data for volatile compounds from EOs and hydrosols were analyzed using Principal Component Analyses (PCA) to demonstrate variations in the composition of the volatile compounds identified. Isolated samples of EO and hydrosols were analyzed for their antioxidant activity using two methods, DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (Oxygen Radical Absorbance Capacity). The essential oils showed higher antioxidant activity than the hydrosols in ORAC method, but lower activity by the DPPH method. The isolates were also tested for their antiproliferative activity on different types of cancer cells and also on two lines of healthy cells, and the results showed that the extracts were not toxic to the cell lines tested. Total polyphenols, total tannins, total flavonoids and total phenolic acids were also analyzed and determined spectrophotometrically. The free volatile compounds of Veronica austriaca ssp. jacquinii can be considered as a safe natural product. Full article

The Asteraceae (Compositae) family is one of the largest angiosperm families that has a large number of aromatic species. Pulicaria undulata is a well-known medicinal plant that is used in the treatment of various diseases due to its essential oil (EO). The EO of both Saudi and Egyptian ecospecies were extracted via hydrodistillation, and the chemical compounds were identified by GC–MS analysis. The composition of the EOs of Saudi and Egyptian ecospecies, as well as other reported ecospecies, were chemometrically analyzed. Additionally, the phytotoxic activity of the extracted EOs was tested against the weeds Dactyloctenium aegyptium and Bidens pilosa. In total, 80 compounds were identified from both ecospecies, of which 61 were Saudi ecospecies, with a preponderance of β-pinene, isoshyobunone, 6-epi-shyobunol, α-pinene, and α-terpinolene. However, the Egyptian ecospecies attained a lower number (34 compounds), with spathulenol, hexahydrofarnesyl acetone, α-bisabolol, and τ--cadinol as the main compounds. The chemometric analysis revealed that the studied ecospecies and other reported species were different in their composition. This variation could be attributed to the difference in the environmental and climatic conditions. The EO of the Egyptian ecospecies showed more phytotoxic activity against D. aegyptium and B. pilosa than the Saudi ecospecies. This variation might be ascribed to the difference in their major constituents. Therefore, further study is recommended for the characterization of authentic materials of these compounds as allelochemicals against various weeds, either singular or in combination. Full article

The integration of green natural chemical resources in agricultural, industrial, and pharmaceutical applications allures researchers and scientistic worldwide. Cleome amblyocarpa has been reported as an important medicinal plant. However, its essential oil (EO) has not been well studied; therefore, the present study aimed to characterize the chemical composition of the C. amblyocarpa, collected from Egypt, and assess the allelopathic, antioxidant, and anti-inflammatory activities of its EO. The EO of C. amblyocarpa was extracted by hydrodistillation and characterized via gas chromatography–mass spectrometry (GC-MS). The chemometric analysis of the EO composition of the present studied ecospecies and the other reported ecospecies was studied. The allelopathic activity of the EO was evaluated against the weed Dactyloctenium aegyptium. Additionally, antioxidant and anti-inflammatory activities were determined. Forty-eight compounds, with a prespondence of sesquiterpenes, were recorded. The major compounds were caryophyllene oxide (36.01%), hexahydrofarnesyl acetone (7.92%), alloaromadendrene epoxide (6.17%), myrtenyl acetate (5.73%), isoshyobunone (4.52%), shyobunol (4.19%), and trans-caryophyllene (3.45%). The chemometric analysis revealed inconsistency in the EO composition among various studied ecospecies, where it could be ascribed to the environmental and climatic conditions. The EO showed substantial allelopathic inhibitory activity against the germination, seedling root, and shoot growth of D. aegyptium, with IC₅₀ values of 54.78, 57.10, and 74.07 mg L⁻¹. Additionally, the EO showed strong antioxidant potentiality based on the IC₅₀ values of 4.52 mg mL⁻¹ compared to 2.11 mg mL⁻¹ of the ascorbic acid as standard. Moreover, this oil showed significant anti-inflammation via the suppression of lipoxygenase (LOX) and cyclooxygenases (COX1, and COX2), along with membrane stabilization. Further study is recommended for analysis of the activity of pure authentic materials of the major compounds either singularly or in combination, as well as for evaluation of their mechanism(s) and modes of action as antioxidants or allelochemicals. Full article

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is the most important pest of cruciferous vegetables worldwide. In this study, we evaluated the properties of selected farnesyl derivative compounds against P. xylostella. The toxicity and sublethal concentration (LC₅₀) of farnesyl acetate, farnesyl acetone, farnesyl bromide, farnesyl chloride, and hexahydrofarnesyl acetone were investigated for 96 h. The leaf-dip bioassays showed that farnesyl acetate had a high level of toxicity against P. xylostella compared to other tested farnesyl derivatives. The LC₅₀ value was 56.41 mg/L on the second-instar larvae of P. xylostella. Then, the sublethal effects of farnesyl acetate on biological parameters of P. xylostella were assessed. Compared to the control group, the sublethal concentration of farnesyl acetate decreased pupation and emergence rates, pupal weight, fecundity, egg hatching rate, female ratio, and oviposition period. Furthermore, the developmental time of P. xylostella was extended after being exposed to farnesyl acetate. Moreover, the application of farnesyl acetate on P. xylostella induced morphogenetic abnormalities in larval–pupal intermediates, adults that emerged with twisted wings, or complete adults that could not emerge from the cocoon. These results suggested that farnesyl acetate was highly effective against P. xylostella. The sublethal concentration of farnesyl acetate could reduce the population of P. xylostella by increasing abnormal pupal and adults, and by delaying its development period. Full article

Herbicides are natural or synthetic chemicals used to control unwanted plants (weeds). To avoid the harmful effects of synthetic herbicides, considerable effort has been devoted to finding alternative products derived from natural sources. Essential oils (EOs) from aromatic plants are auspicious source of bioherbicides. This review discusses phytotoxic EOs and their chemical compositions as reported from 1972 to 2020. Using chemometric analysis, we attempt to build a structure-activity relationship between phytotoxicity and EO chemical composition. Data analysis reveals that oxygenated terpenes, and mono- and sesquiterpenes, in particular, play principal roles in the phytotoxicity of EOs. Pinene, 1,8 cineole, linalool, and carvacrol are the most effective monoterpenes, with significant phytotoxicity evident in the EOs of many plants. Caryophyllene and its derivatives, including germacrene, spathulenol, and hexahydrofarnesyl acetone, are the most effective sesquiterpenes. EOs rich in iridoids (non-terpene compounds) also exhibit allelopathic activity. Further studies are recommended to evaluate the phytotoxic activity of these compounds in pure forms, determine their activity in the field, evaluate their safety, and assess their modes of action. Full article

Chemical profile and antioxidant activity of the species Veronica saturejoides Vis. ssp. saturejoides (Plantaginaceae)—which is endemic to Croatia, Bosnia and Herzegovina and Montenegro —were investigated. Volatile compounds produced by glandular trichomes (composed of one stalk cell and two elliptically formed head cells according to scanning electron microscope investigation) were isolated from the plants collected in two locations. Additionally, as a part of specialized metabolites, total polyphenols, total tannins, total flavonoids and total phenolic acids were determined spectrophotometrically. In the lipophilic volatile fractions-essential oils, the most abundant compounds identified were hexahydrofarnesyl acetone, caryophyllene oxide and hexadecanoic acid. In total, the class of oxygenated sesquiterpenes and the group of fatty aldehydes, acids and alcoholic compounds dominated in the essential oils. In the hydrophilic volatile fractions-hydrosols, the most abundant compounds identified were trans-p-mentha-1(7),8-dien-2-ol, allo-aromadendrene and (E)-caryophyllene. A group of oxygenated monoterpenes and the sesquiterpene hydrocarbons dominated in the hydrosols. Antioxidant activity of essential oils and hydrosols was tested with two methods: 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC). Essential oils showed higher antioxidant activity than hydrosols and showed similar antioxidant activity to Rosmarinus officinalis essential oil. Obtained results demonstrate that this genus is a potential source of volatiles with antioxidant activity. Full article

The variation in habitat has a direct effect on the plants and as a consequence, changes their content of the bioactive constituents and biological activities. The present study aimed to explore the variation in the essential oils (EOs) and phenolics of Heliotropium curassavicum collected from the coastal and inland habitats. Additionally, we determined their antioxidant and allelopathic activity against the weed, Chenopodium murale. Fifty-six compounds were identified as overall from EOs, from which 25 components were identified from the coastal sample, and 52 from the inland one. Sesquiterpenes were the main class in both samples (81.67% and 79.28%), while mono (3.99% and 7.21%) and diterpenes (2.9% and 1.77%) represented minors, respectively. Hexahydrofarnesyl acetone, (-)-caryophyllene oxide, farnesyl acetone, humulene oxide, farnesyl acetone C, and nerolidol epoxy acetate were identified as major compounds. The HPLC analysis of MeOH extracts of the two samples showed that chlorogenic acid, rutin, and propyl gallate are major compounds in the coastal sample, while vanilin, quercetin, and 4′,7-dihydroxyisoflavone are majors in the inland one. The EOs showed considerable phytotoxicity against C. murale with IC₅₀ value of 2.66, 0.59, and 0.70 mg mL⁻¹ for germination, root, and shoot growth, respectively from the inland sample. While the coastal sample attained the IC₅₀ values of 1.58, 0.45, and 0.66 mg mL⁻¹. MeOH extracts revealed stronger antioxidant activity compared to the EOs. Based on IC₅₀ values, the ascorbic acid revealed 3-fold of the antioxidant compared to the EO of the coastal sample and 4-fold regarding the inland sample. However, the ascorbic acid showed 3-fold of the antioxidant activity of the MeOH extracts of coastal and inland samples. Although H. curassavicum is considered as a noxious, invasive plant, the present study revealed that EO and MeOH extracts of the H. curassavicum could be considered as promising, eco-friendly, natural resources for antioxidants as well as weed control, particularly against the weed, C. murale. Full article

Impatiens parviflora is non-native invasive plant species occupying large areas all over the Europe and threatens native communities by altering their species composition and reducing native biodiversity. The factor responsible for its spreading could be explained by releasing biochemical to the environment. On the other hands, high demand on secondary metabolites as potential source of new ecofriendly biocides could be beneficial. The analysis of I. parviflora essential oil (EO) led us to identify more than 60 volatiles. The main compound was hexahydrofarnesyl acetone, other dominant components were phytol, carvacrol, germacra-4(15),5,10(14)-trien-1-α-ol, and pentacosane. The potential phytotoxic effect of I. parviflora EO collected in two vegetation periods (summer and autumn) was evaluated on seed germination and root elongation of three dicot species (Raphanus sativus, Lepidum sativum, and Lactuca sativa) and on one monocot species (Triticum aestivum). The seed germination of only one dicot species, L. sativa, was affected by both EOs. In contrast, seed germination of monocot species T. aestivum was influenced only by the highest doses of EOs isolated from I. parviflora in autumn. The root elongation of tested plant species was less influenced by I. parviflora EOs. L. sativum showed sensitivity to one dose of EOs hydrodistilled in summer, while the monocot species was influenced by both EOs samples in highest doses. Our findings revealed that I. parviflora contained phenolics that were phytotoxic to the germination of some plant species, mainly at higher EOs doses, while root elongation of tested plants was not suppressed by essential oils. Full article