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The chemical composition and in vitro anti-inflammatory, antioxidant and antimicrobial activities of the leaf essential oil of Machils konishii has been investigated. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Sixty-six compounds were identified, representing 100% of the oil. The main components identified were a-pinene (33.9%), α-pinene (13.9%), and thymol (12.0%); The leaf oil was able to reduce nitric oxide production by lipopolysaccharide-activated murine macrophages RAW 264.7 without reducing the cell viability. In addition, the leaf oil showed strong antioxidant and antimicrobial activities. The major ingredient of the oil that was responsible for the anti-inflammatory, antioxidant and antimicrobial activities was thymol.

Epoxides are relatively reactive compounds and may undergo decomposition or rearrangement reactions at elevated temperatures, and gas chromatographic analysis of essential oils may cause thermal decomposition or rearrangement of epoxide components at gas chromatographic temperatures. Density functional theory (DFT) calculations were carried out using the B3LYP functional at the 6-31 1++G**//6-3 IG* level of theory on the Meinwald rearrangements of α- pinene oxide (two different mechanisms leading to transpinocamphone and a-campholenal), cis-limonene oxide (leading to trans-dihydrocarvone), tran s- limonene oxide (leading to cisdihydrocarvone), 6,7-epoxymyrcene (leading to 2-methyl-6-methylene-7-octen-3-one), and 1,2-epoxy-2,5-dimethyl-3-viny4- hexene (two mechanisms leading to 5-methyl-3-vinyl-4-hexenal and 8-methyl-5,7-nonadien-2-one). Free energies of activation for the uncatalyzed Meinwald rearrangement of common monoterpene epoxides are relatively large, being of the order of 70 kcal/mol, and are, therefore, not predicted to be important reactions at gas chromatographic temperatures.

The in vitro and in vivo antioxidant activities and its potential to protect against amyloid-P toxicity of essential oils from Zelkova serrata (Thunb.) Makino were investigated in the model organism Caenorhabditis elegans. The results revealed that the essential oil of Z serrata heartwood exhibited great radical scavenging activities and high total phenolic content. In vivo assays showed significant inhibition of oxidative damage in wild-type C. elegans under juglone- indueed oxidative stress and heat shock. Based on results from both in vitro and in vivo assays, the major compound in essential oil of heartwood, (-)-(S, 4S)- 7-hydroxycalamenene (IS, 4S-7HC), may contribute significantly to the observed antioxidant activity. Further evidence showed that IS, 4S-7HC significantly delayed the paralysis phenotype in amyloid beta-expressing transgenic C. elegans. These findings suggest that IS, 4S-7HC from the essential oil of Z serrata heartwood has potential as a source for antioxidant or Alzheimer's disease treatment.

Kabuchii (Citrus keraji var. kabuchii hort. ex Tanaka, Rutaceae) is a peculiar Okinawan citrus fruit. Local farmers cultivating various Citrus fruits say that the fragrance of Kabuchii is the most relaxing, but, there are few reports on the biological effects of the essential oil of Kabuchii and its chemical components [1]. In this study, the sedative effects of inhalation of the vaporized Kabuchii essential oil in open field, Rotarod, and pentobarbital sleep tests are compared with diazepam, as a positive control. In the open field test, both Kabuchii essential oil and diazepam decreased the spontaneous motor activity dose-dependently. The reduction in spontaneous motor activity in the 0.3 mg/cage (ca. 0.0278 mg/L) Kabuchii essential oil group was greater than that in the 1 mg/kg diazepam group. In the Rotarod test, Kabuchii did not affect the motor performance, even at the highest dosage tested (3 mg/cage), whereas diazepam decreased it dose-dependently. The effects of the major or characteristic components of Kabuchii, d-limonene, γ-terpinene, thymol, and p-cymene, were also evaluated in the open field and Rotarod tests. γ-Terpinene and thymol significantly decreased spontaneous motor activity at a dosage of 0.3 mg/cage, without affecting motor performance. Thus, γ-terpinene was estimated to be the main active component. Reduction in spontaneous motor activity by γ-terpinene in the open field test was not observed in intranasal zinc sulfate irrigation-induced anosmic mice. In the pentobarbital sleep test, both Kabuchii essential oil and diazepam potentiated pentobarbital-induced loss of the righting reflex (LRR). The LRR duration prolonging effects of both treatments were inhibited by pretreatment with flumazenil, a benzodiazepine receptor antagonist. The LRR latency reducing effect of Kabuchii was not affected by flumazenil, while that of diazepam was suppressed by it. γ-Terpinene showed similar potentiating effects on pentobarbital-induced sleep. Thus, vaporized Kabuchii essential oil and its active component, γ-terpinene, have sedative effects comparable with diazepam without inducing motor incoordination, which is a well-known side effect of diazepam.

The chemical composition of the essential oil (EO), microwave extract (ME) and hydrolate extract (HE) from the same batch of leaves of Fortunella japonica, was investigated: by combination of chromatographic (GC, CC) and spectroscopic techniques (GC-MS, 13C NMR). F. japonica essential oil and extracts are complex mixtures of 28-60 compounds being mainly oxygenated sesquiterpenes. The EO composition was dominated by germacrene D (14.9%), β-elemol (9.1%), cis-guai-6-en-10β-ol (6.3%), β-eudesmol (5.5%), and δ-elemene (5.2%). Limonene was the unique monoterpene identified at appreciable amount (7.1%). The extract obtained by microwave assisted hydrodistillation contained as main components: β-elemol (12.4%), germacrene D (9.9%), cis-guai-6-en- 10β-ol (9.0%), β-eudesmol (8.2%), germacra-l(l0),5-dien-4α-ol (7.1%) and α-eudesmol (6.4%). Finally, the highest content of oxygenated sesquiterpenes (near 92%) was found in the hydrolate extract displaying cryptomeridiol (23.3%, but totally absent in the EO and ME), β-eudesmol (20.6%) and α-eudesmol (10.7%). Combined analysis by chromatographic and spectroscopic techniques appeared useful for identification of various sesquiterpenols bearing a tertiary alcohol function.

The present study evaluates the chemical composition and olfactory description of the essential oils of Asarum glabrum Merr., Calocedrs macrolepis Kurz, Cunninghamia lanceolata (Lamb.) Hook. and Glyptostrobus pensilis (Stainton ex D.Don) K. Koch. The essential oils were obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-FID and GC-MS. Concerning their chemical composition, 66, 42, 57 and 21 volatile compounds were identified from dried leaves in the case of Asarum glabrum Merr. and wood for the other three, representing 98.7%, 67.2%,,92.0% and 87.5 % of the total composition, respectively. The main compounds of Asarum glabrum oil were safrole (38.1%), apiole (10.8%) and myristicin (8.0%); of Calocedrus macrolepis verbenone (9.3%), piperitone (8.6 %), a-terpineol (6.0%) and (Z)-p-terpineol (5.3%); of Cunninghamia lanceolata oil cedrol (26.3%), a-terpineol (24.1%) and camphor (7.0%); and of Glyptostrobus pensilis oil dihydro-eudesmol isomer (assumed) (18.3%), cedrol (16.4%), occidentalol (13.2%) and elemol (9.0%).

Treating inflammatory conditions .such as vaginosis, vaginitis, and vulvovaginitis in pregnancy is- a special problem due to limitations. of available drugs. However, possible treatment options can be found also in naturally originated products, such as essential oils (EOs) of different plants. The aim of this study was to evaluate in -vitro antimicrobial and toxic activities of the commercial EO of Rosmiarinus officinalis L. (Lamiaceae) against five Gram-positive and Gram-negative bacterial strains and two Candida strains obtained from pregnant women with Vaginal infection. Gas chromatography-mass spectrometry of the tested EO revealed oxygenated monoterpenes to be the major ingredients, while microdilution assay showed the highest activity on Staphylococcus aureus II strain at 6.2 mg/mL. After 24 hours, toxicity was determined at 19.4 mg/mL on Artemia salina nauplii. The obtained results show this EO to be a promising alternative therapy for vaginal infections, although further toxicity and safety research is required.

Essential oils (EO) from leaves and branches of Nectandra puberda Schott (Nees) and from leaves of N. cuspidata NeesMart. were obtained by hydrodistillation and their chemical compositions determined by gas chromatography - mass spectrometry (GC-MS). The main compounds identified from N. puberula EO were apiole (22.2%), β-caryophyllene (15.1%), β-pinene (13.3%), germacrene D (8.3%), pogostol (6.6%) and bicyclogermacrene (6.4%) in the leaves; and apiole (28.1%), pogostol (19.8%) and guaiol (11.2%) in the branches. The EQ of N. cuspidata leaves showed β-caryophyllene (26.9%), bicyclogermacrene (16.0%) and spathulenol (5.2%) as the main compounds. The EOs were subjected to antibacterial screening and displayed promising activity against Escherichia coli (MIC = 19.5 μg.mL⁻¹). In addition, the EOs were tested for cytotoxic activity against MCF-7 breast tumor cells and the IC₅₀ values were 64.5 ± 1.6 and 117.1 ± 11.9 μg.mL⁻¹ for the leaf EOs of N. puberula and N. cuspidata, respectively.

The essential oil of aerial parts of Helichrysum conglobatum (Viv.) Steudel. (Asteraceae) from Cyprus was analyzed by GC and GC-MS. The essential oil yield was 0.01, v/w. Forty five compounds were identified in the oil comprising 96.1% of the total. The essential oil was mainly composed of sesquiterpene type compounds and oxygenated sesquiterpene derivatives. The main components of the oil were P-caryophyllene (14.6%), Y-curcumene (14.1%), hexadecanoic acid (13.5%), tetradecanoic acid (7.5%), rosifoliol (5.4%) and 6-cadinene (5.3%). This is the first report on the essential oil composition of H. conglobatum from Cyprus.

The aim of the present study was the chemical analysis of the essential oils from Juniperus phoenicea and J. drupacea female cones and evaluation of their biological effects. Fresh samples, collected in Greece, were subjected separately to hydrodistillation and the oils obtained analyzed by GC-FID and GC-MS. The oils Were assessed using the CAM (chorioallantoic membrane) assay to evaluate their anti-angiogenic potential and the lack of irritant effects in topical application. GC analysis showed that mainly quantitative differences among the samples were observed: limonene was the most abundant compound in J. drupacea (27.0%) compared with J. phoenicea oil (1.6%); the content of a-pinene was high in both essential oils (J. phoenicea 22.1%, J. drpacea 26.1%) followed by germacrene D (J. phoenicea 7.4%, J. drpacea 7.1%, respectively). Nevertheless, qualitative differences were also detected as the diterpene 4-epi-abietal was present in a considerable amount (13.2%) in J. phoenicea essential oil, but was not detected in J. drupacea oil. In the CAM assay, only J. phoenicea. essential oil evidenced a rather weak anti-angiogenic activity compared with the standard retinoic acid, but no irritant effect was observed for either essential oil suggesting their safety for topical application.

Essential oils from the two most representative shrub species from the Iberian Peninsula (namely Cistus ladanifer L. and Erica arborea L.) have been characterized by Fourier transform infrared spectroscopy (FTIR) and thermoanalytical techniques (TG/DTG and DSC). Vibrational spectra have been compared with those of components of the plants, and with those of oils, gums and resins from other species. The different content in terpenoids of C. ladanifer oil (mainly mono- and- sesquiterpenoids) and E. arborea oil (mainly triterpenoids) is reflected in the ATR-FTIR by the position of the bands at around 2873 cmf⁻¹, 1730 cm-⁻¹ and 1678 cm⁻¹ As regards their thermal behavior, C. ladanifer-derived oil evinced higher thermal stability than that of obtained from E arborea: the pyrolysis of the former was sensitized at 210°C, whereas for the later it occurred at 143°C. These temperatures are high enough to state that thermolabile constituents such as terpenoids are conserved in the hydrodistillation and that this extraction process ensures the recovery of the main constituents of both-essential oils.

The chemical composition and mosquito larvicidal and adulticidal activity of five essential oils (EOs), Dracocephalum ruyschiana L. (DR), D. foetidum Bunge (DF), D. moldavica L. (DM), D. fruticulosum Steph. ex Willd. (DFr) and D. peregrinum L. (DP) were evaluated. Simultaneous GC-FID and GC-MS analyses revealed in the EOs of DR, DF and DM an unidentified compound (1) ([M'122], 5.4%, 57.9% and 74.0%, respectively). Therefore, we aimed to isolate compound 1 using Preparative Capillary GC (PCGC) connected to a Preparative Fraction Collector (PFC) system. Structure determination of 1 was determined by 'H- and 3C-NMR as p-mentha-1,8-dien-10-al (1, limonen-10-al). Other detected major constituents were thymol (34.0%) and carvacrol (6.1%) in DR; limonene (28.8%) in DF; cis-chrysanthenol acetate (29.1%) and trans-verbenol (5.0%) in DFr; and linalool (17.9%), trans-o-bergamotene (7.9%), (E)- nerolidol (7.7%) and eugenol (5.5%) in DP. The DFr, DP, DR and DM EOs produced 100% mortality to 1st instar larvae of Aedes aegypti L. at 250 ppm and DR and DM EO exhibited the strongest activity and killed 100% 1st instar larvae at 62.5 ppm. No adulticidal activity was observed against female Ae. aegypti. In the scope of the present study, for the first time isolation of limonen-I0-al (1) from DR, DM, and DP EOs and larvicidal activity of five Dracocephalum EOs were reported.

Plants and their extracts are the new field of interest for many scientists and also of some pharmaceutical industries. In order to provide more information for their usage in the prevention and treatment of diseases many clinical trials and researches are being carried out. In this review the biological activities and the mechanism of action of volatile phenylpropanoids (PPs) found in essential oils (EOs) are presented. The aim of this overview is to show that volatile PPs found in EOs can exert many of the biological activities which are generally attributed to EOs. Almost all of the PPs possess antimicrobial, anti-inflammatory and anticancer activities. These are related to the different substitution of the phenylpropane molecule. For each isolated group not only one, but more pharmacological activities can be credited.

Malaria is one of the most important public health problems worldwide. This illness is controlled, mainly, by combating the vector mosquitoes using chemical insecticides, but this use has caused environmental impact and the emergence of tolerance in adult mosquitoes. Herein, we report the larvicidal activity of nine chemical constituents found in essential oils against third-instar larvae of Anopheles gambiae. All the tested compounds showed larval toxicity. Among the nine effective components, citronellol exhibited a pronounced larvicidal effect against the larvae of An. gambiae, with LC₅₀ values of 96.1 and 55.6 ppm after 12 and 24 hours of treatment, respectively; however, hydroxycitronellal was the most potent compound after 48 and 72 h of exposure (LC₅₀=3.7 and 2.3 ppm, respectively), followed by citronellol (LCso= 16.7 and 6.3 ppm, respectively). Moreover, larval mortality was concentration- and time-dependent.

Essential oil of Mentha spicata L. var. viridis 'Ganga', an indigenously developed variety, was chemically profiled using various gas chromatographic techniques. Piperitenone oxide was characterized as the most exclusive constituent (69.7%) along with a new C₃-oxygenated p-menthane alcohol,- diosphenolene (1.6%). Enantiomeric discrimination revealed (4S)-(-)-limonene, (R)-(-)-linalool and (lS,2S)-(+)-piperitenone oxide as predominant enantiomers. The oil contained mainly C₃-oxygenated p-menthane monoterpenoids, which are distinctive of peppermint, instead of the characteristic C₆-oxygenated class of spearmint. The present findings will aid in understanding the pathway and cause of C₃-oxygenation in a spearmint taxon. The essential oil and pure piperitenone oxide showed growth inhibiting properties and thus, may be utilized in antifungal preparations for disease management of medicinal and aromatic plants.

The chemical constituents and anti-inflammatory activity of the essential oil from the leaf of Jatropha curcas L (Euphorbiaceae) collected from Nigeria are reported. The analysis of the chemical constituents of the essential oil was achieved by using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). All constituents of the essential oil, namely neophytadiene (35.8%), phytol (23.1%), trans-pinane (12.7%), 6,10,14-trimethyl-2- pentadecanone (12:3%) and citronellyl propanoate (11.2%), were present in significant amounts. The anti-inflammatory activity of the leaf oil was determined on Wistar rats using egg-albumin as phlogistic agent; significant inhibition (P0.05) was shown at a dose of 2%, v/v. Percentage inhibition of the anti- inflammation increased steadily to 76.6% in the 4th hour.

The composition of the volatile fraction of Malva sylvestris var. mauritiana (L.) Boiss. (Malvaceae) was investigated. This plant species was cultivated in the southeastern Alps as an ingredient for herbal teas and infusions. Flowers and leaves were collected at the end of the summer season and separately steam- distilled to obtain two volatile oils, the yields of which were 0.019% for leaves and 0.012% for flowers. After GC-FID and GC-MS analyses, the two oils -revealed differences in the nature and especially in the proportion of their components, which were aldehydes, alcohols, phenolics, esters, hydrocarbons and acids. Eugenol was the single most abundant compound in the leaves, totalling 46.7% of the total oil, followed by phytol with 34.4%. Flowers showed a predominance of hydrocarbons, among which the anteiso branched-chain saturated hydrocarbon, 3-methyl tricosane, was the most abundant compound, accounting for 14.9% of the total volatiles. Eugenol ranked second with 10.3%, followed by the two linear-chain saturated hydrocarbons pentacosane and tricosane forming 8.2 and 7.7% of the total oil, respectively. The occurrence and the relative abundance of compounds from various chemical classes such as phenolics, hydrocarbons and aromatic aldehydes and alcohols are discussed, together with some of their ecological implications. The obtained volatile oils were than tested against two major honeybee (Apis mellifera) pathogens, namely Paenibacillus larvae and Melissococcus plutonius, the causative agents of the American and the European foulbrood, respectively.

The compositions of hydrodistillated essential oils of Laser trilobum (L.) Borkh. rhizomes and fruits from Serbia, were investigated using GC and GC/MS. In the dark-blue rhizome oil forty-six compounds (93.1% of the total oil) were identified, with α-pinene (31.5%), γ-terpinene (9.0%), p-cymene (7.9%), β-pinene (6.1%) and 1,4-dimethylazulene (6.0%) as the major components. In the colorless fruits oil, twenty components (96.8% of the total oil) were identified, and the main constituents were limonene (51.6%) and perillaldehyde (26.8%). The antimicrobial activity of the oils was tested using the broth microdilution method against nine bacterial and two fungal strains. The oils revealed significant antimicrobial effect, mainly better than that of thymol, used as a reference compound. The strongest activity was recorded for the rhizome oil against Escherichia coli, Klebsiella pneumoniae and Candida albicans (MICs=25 μg/mL), and the fruit oil against C. albicans ATCC 10259 (MIC=12.5 μg/mL).

A water-distilled essential oil (E) from the aerial parts of Pimpinella cypria Boiss. (Apiaceae), an endemic species in northern Cyprus, was analyzed by GC- FID and GC-MS. Forty-five compounds were identified in the oil, which comprised 81.7% of the total composition. The compound classes in the oil were oxygenated sesquiterpenes (33.9%), sesquiterpenes (22.0%), monoterpenes (11.4%), oxygenated monoterpenes (2.6%), and phenylpropanoids (7.5%). The main components of the oil were (Z)-β-farnesene (6.0%), spathulenol (5.9%), ar-curcumene (4.3%), and 1,5-epoxy-salvial(4)14-ene (3.8%). The P. cypria EO deterred yellow fever mosquitoes (Aedes aegypti) from biting at a concentration of 10 μg/cm2 in in vitro bioassays. The oil was tested for repellency in assays using human volunteers. The oil had a minimum effective dosage (MED) for repellency of 47 ± 41 μg/cm² against Ae. aegypti, which was less efficacious than the positive control NN-diethyl-3-methylbenzamide (DEET). In larval bioassays, P. cypria EO showed an LC₅₀ value of 28.3 ppm against 1st instar Ae. aegypti larvae. P. cypria EO demonstrated dose dependent repellency against nymphs of the lone star tick, Amblyomma americanum. Between 45.0% and 85.0% repellency was observed at concentrations ranging from 26 to 208 μg/cm². However, P. cypria EO was less effective compared with DEET in the tick bioassays. Cytotoxicity assays showed that the P. cypria EO did not exhibit significant effects up to the maximum treatment concentration of 50 μg/mL on HEK293, PC3, U87MG, and MCF cells. P. cypria EO also demonstrated moderate antimicrobial activity against Gram-negative and -positive bacteria with MICs ranging from 15.6 to 62.5 μg/mL, except for Candida albicans, which showed the same MIC value of 7.8 μg/mL as the positive control, flucytosine. This is the first report on the chemical composition of P. cypria EO and its insecticidal, toxicant, cytotoxic, and antimicrobial activity.

In this study, the changes caused by variation of altitude to the essential oils (EOs), fatty acid methyl esters (FAMEs), and antimicrobial activities of Primula vulgaris Huds. subsp. vulgaris ( Pvv) and P. vulgaris Huds. subsp. sibthorpii (Hoffmanns) W.W. Sm. & Forrest ( Pvs)) grown in Turkey were investigated. Major fluctuations in the composition of Pvv and Pvs oils included methyl-4-methoxy salicylate (4.5–35.3%; Pvv and 3.2–37.2%; Pvs), ( Z,Z,Z)-7,10,13-hexadecatrienal (5.1–21.8%; Pvv and 4.4–15.2%; Pvs) and flavone (5.5–14.9%; Pvv and 1.6–18.0%; Pvs). Fatty acid profile (C6:0–C26:0) changes were noted in Pvv and Pvs. Methyl hexadecanoate (2.4–9.3%) and methyl octadecanoate (1.0–4.7%) were present in all the FAME samples of the plants. The antimicrobial activity of the EOs of Pvv and Pvs were tested against nine bacterial species, which showed activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) varying from 8.5 to 59.2 μg/mL in all samples, respectively, depending on the altitude at which the oils were obtained.

Species of Narcissus (family Amaryllidaceae) are a potential source for large-scale extraction of alkaloids and fragrances. The bulbs typically accumulate a large number of alkaloids, including galantamine, a benzazepine alkaloid proven to be a cholinesterase inhibitor and which is used in the treatment of Alzheimer's disease. The presence of galantamine in N. poeticus L. collected in Abruzzo (Italy) was assessed and several levels of alkaloid were found in all parts of the plant (flower, stem, bulb and root) and not only in the bulb. The amount of galantamine obtained was tested by using two different extraction solvents. Extraction of N. poeticus absolute from the flowers was also performed, as this product is an important floral note in perfumery, and the distribution of allergenic compounds in the coronas and in the tepals was assessed. Moreover, the in vitro propagation of N. poeticus was tested as it may be a valuable resource from which to produce biomolecules, as an alternative to chemical synthetic processes.

The absorption and metabolism of phytogenic feed additives in poultry is studied related to the metabolism and deposition of their main compounds in tissues intended for food production. Fifty-six non-sexed Ross 308 broilers were allocated to seven dietary treatments and fed a diet containing graded levels of thyme (Thymus vulgaris L.) essential oil (EO) (0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.1%, w/w). Thymol concentration was measured in plasma, liver, kidney and breast muscle tissue using solid phase micro-extraction followed by gas chromatography/mass spectrometry. We found the highest concentrations of thymol in kidney and plasma, and the lowest in breast muscle and liver. Thymol content in plasma and kidney significantly increased when 0.05 and 0.1%, w/w, EO and in liver and breast muscle only when 0.1%, w/w, EO was added to the diet (p0.05). Our results indicate intensive metabolism of thymol in liver and its accumulation in kidney tissue. We confirm low deposition of thymol in the muscle tissue. It is necessary to.-keep in mind the selection of a sufficient concentration of EO in the feed additive for animals without the risk of thymol residues in edible tissues.

Leaves of Juglans regia L. collected from two different locations [Adana (A) and Ankara (B)] from Turkey were subjected to hydrodistillation in a Clevenger type apparatus to yield the essential oils (EOs). GC/MS and GC-FID analyses revealed that the A EO was rich in thymol (23.1%), while caryophyllene oxide (33.8%) was found as the main constituent of B EO. Both contained P-eudesmol (1.4% - 9.5 %), (E)-geranyl acetone (3.7% - 5.8%) and the eudesmane type constituent juglaterpene A (3.1% - 11.0%). Using a HP Innowax preparative capillary column connected to a preparative fraction collector, an unknown constituent, juglaterpene A (1, 1 l-hydroxy-2,4-cycloeudesmane), was isolated in a rapid one-step manner with94.0% purity. Structure determination was accomplished from ID- and 2D-NMR spectroscopic data. Oil B demonstrated significant larvicidal activity against 1st instar Aedes aegypti L.

Detailed GC and GC/MS analyses of essential-oil samples obtained by hydrodistillation of Morus alba L. and M nigra L. leaves (four samples) allowed the identification of 131 constituents representing 95.1 - 96.4% of the total GC peak areas. The most abundant compounds classes were alkanes, diterpenoids, carotenoid-derived compounds and fatty acid-related constituents with trans-phytol (7.9 - 71.2%), (E,E)-geranyl linalool (0.2 - 8.0%), (Z)-bovolide (8.1/) and n-chain alkanes (in total, 17.5 - 52.4%) as the major constituents of the analyzed samples. In general, there were only quantitative differences noted between M nigra essential oils from fresh and dry leaves. The most discernable changes included a variation in the content of the major constituents (e.g. the relative amount of trans-phytol and the total amount of alkanes decreased by 5.8% and ≈ 2%, respectively, while that of (E,E)-geranyl linalool increased by 7.8%). On the other hand, the composition of M. alba essential oil was much more significantly affected by the drying process. The highest quantitative differences were noted for trans-phytol, geranyl acetone, and all isomers of 4,6,8-megastigmatrien-3-one. Also, a rare plant metabolite, (Z)-bovolide, characteristic of leaf senescence, was only identified (8.1%) in the essential oil of M alba dried leaves.

The hydrodistilled leaf essential oil (EO) of Tagetes patula L. was analyzed by GC-FID and GC-MS. The main components of the oil were characterized as caryophyllene oxide (18.4%), p-caryophyllene (18.0%) and spathulenol (9.1%). The EO was screened for its biting deterrent activity against Aedes aegypti L. using the in vitro KD module system. T. patula EO exhibited good biting deterrent activity. The results suggest that these sesquiterpenes may contribute to biting deterrent activity, but the role of minor components cannot be excluded. T. patula EO also showed 100, 90 and 10% mortality at dosages of 125, 62.5 and 31.25 ppm, respectively, in I-day-old larvae of Ae. aegypt.

Hofmeisteria schaffneri is used in Mexican folk medicine for treating painful gastric complaints. Therefore, in this paper the smooth muscle relaxant effect of the essential oil, and an infusion of the whole plant were evaluated using the gastrointestinal transit test in mice. The results revealed that both preparations at 316 mg/kg inhibited gastrointestinal transit by 47.5 and 52.1%, respectively. The common component of the infusion and essential oil was 8,9-epoxy-10-acetoxythymol angelate (2), which inhibited the gastrointestinal transit by 53.4% at a dose of 31.6 mg/kg. An HPLC-UV method was developed and validated to quantify 2. The chromatographic conditions were: A LiChrospher® 100 RP-18 column (250 × 4 mm i.d., 5 μm) with a mobile phase composed of CH3CN-H2O, in a gradient run at a flow rate of 0.6 mL/min, using a wavelength of 215 nm. The method was linear, precise, accurate, and showed excellent recovery. According to the results, compound 2 can be used as a marker for the quality control procedures of the crude drug of H. schaffneri.

Essential oil was obtained in a yield 1.1%, w/w, by steam distillation of Elionurus tristis leaves from Madagascar. The chemical composition was analyzed qualitatively and quantitatively by GC-MS and GC-FID, respectively. To the best of our knowledge, this is the first chemical analysis of this essential oil. Seventy-three compounds were identified, corresponding to 94.9% of the total essential oil. The principal compounds were sesquiterpenes and the more represented were β-gurjunene (18.4%), neoclovene (15.8%) and nootkatone (10.4%). Through a comparative study, we observed a large variability between the components of E. tristis essential oil and those from others species of the same genus. Evaluation of the antioxidant (ABTS and DPPH assays) and anti-tuberculosis activities of the essential oil showed weak antioxidant potency but an interesting anti-tuberculosis activity with a MIC of 32 mg/L. This activity prompted us to evaluate individually the major components for the treatment of tuberculosis.

Methyl 3-(5-(prop-l-yn-l-yl)thiophen-2-yl)propanoate (1), biosynthetically and structurally related to dehydromatricaria ester, was isolated from the root essential oil of Artemisia absinthium L. (0.7% of the total oil). This is the second record of this compound and the very first one regarding it as an essential-oil constituent. In this paper, we give details regarding its isolation, structural elucidation and gas chromatographic properties (RI on DB-5 MS column: 1694). The NMR-based identification of the compound was corroborated by simulation of its 'H- and "C-NMR spectra using a GIAO method (DFT level of theory). A tentative biosynthetic pathway, possibly leading to this compound, is also proposed.

The chemical composition, antibacterial and α-glucosidase inhibitory activities of the essential oils obtained from hydrodistillation of the fresh stem and leaf of Neolitsea coccinea B. C. Stone are reported for the first time. GC and GC-MS analysis revealed the presence of 42 volatile compounds from the stem and leaf oils, accounting for 84.9% and 90.4%, respectively of the identified components. The principle compounds in the stem oil were δ-cadinene (21.2%), 1-epicubenol (11.3%) and cyperotundone (10.7%), while the main compounds in the leaf oil were selin-ll-en-4-α-ol (26.8%), bicyclogermacrene (12.6%), γ-eudesmol (7.1%), germacrene D (6.1%) and globulol (5.9%). The leaf oil demonstrated moderate to weak antibacterial activity towards Bacillus subtilis and Staphylococcus aureus with MIC values of 250 μg/mL and 500 μg/mL, respectively, whereas the stem oil posessed weak antibacterial activity against B. subtilis with a MIC value of 500 μg/mL. The stem and leaf oils showed significant α-glucosidase inhibitory activity with IC(50) values of 32.2 ± 0.8 μg/mL and 70.9 ± 1.1 μg/mL, respectively.

The volatile constituents and insecticidal activity of the essential oil obtained by hydrodistillation of pulverized air-dried leaves of Dehinbolliapinnata Schum.Thonn (Sapindaceae) growing in Nigeria were studied. The constituents of the oil were analyzed by gas chromatography (GC) aid gas chromatography coupled with mass spectrometry (GC-MS). The percentage yield of the oil was 0.04% (v/w). Fourteen compounds were characterized, representing 94.0% of the total volatile component of the oil. The major constituents of the oil were hexahydrofarnesyl acetone (37.5%), fainesyl acetone (17.2%) and geranyl acetone (14.6%). The essential oil, at a concentration of 120 mg/mL, displayed 100% mortality against Sitophilus zeamais at 72 h with a LC(50)40.00 mg/mL air.

The chemical composition, antimicrobial and antiquorum sensing activity of the essential oil of Micromeria thymifolia (Scop.) Fritsch were investigated. Limonene, piperitone epoxide and piperitenone epoxide were found as the main constituents using a gas chromatography-mass spectrometry technique. In vitro antimicrobial activity of the oil was tested against six bacterial and seven fungal strains and high antimicrobial potential was noticed. Minimum inhibitory concentration varied from 0.031 mg/mL to 0.5 mg/mL for bacterial and 0.062 mg/mL to 0.5 mg/mL for fungal strains. The antiquorum properties of the essentidl oil were evaluated on Pseudomonas aeruginosa PAO 1. The oil was tested at subMIC concentrations for anti-quorum sensing activity. The analyses on quorum-sensing functions have been carried out by evaluating twitching and swarming of bacterial cultures and the total amount of pyocyanin production produced by P. aeruginosa. This study showed that M thymifolia essential oil exhibited antiquorum sensing activity and may be used as an antipathogenic drug.

In recent decades, essential oils (EOs) have become an important alternative source of antimicrobial agents. The objective of this study was to evaluate the antimicrobial activity of EOs obtained from the leaves of Myrcianthes leucoxyla Mc. Vaughn., Vallea stipularis L.f and Phyllanthus salviioius Kunth for prevalent microbial strains and also to contribute to the knowledge of their chemical composition. EOs were obtained by hydrodistillation and analyzed by GC-MS. The main compounds for V. stipularis EO were α-tujene (6.6%) and cedrene epoxide (12.0%), for M leucoxila EO 1,8 cineole (6.3%) and caryophyllene oxide (21.7%), and for P. salviifolius aristolene (17.3%) and geranyl tiglate (15.9%). Antimicrobial tests showed that M leucoxyla EO was the most active, showing zones of inhibition against all strains used, specifically against Pseudomonas aenginosa and Salmonella typhimurium with percentages of inhibition higher than 50%. Compared with positive controls, this activity may be related to the presence of 1,8 cineole.

The essential oils (EOs) from aerial parts of Piper aduncum, P. callosuin and P. marginatum, collected from the Amazon region of Brazil, were analyzed by GC-MS and then evaluated for their antifungal and anticholinesterase activities. The essential oils were dominated by phenylpropanoids, such as dillapiole (73.0%) in P. aduncum, safrole (66.0%) in P. callosum and 3,4-methylenedioxypropiophenone (21.8%) in P. inarginatum. The analyzed oils showed low to moderate antifungal activity; with detection limits (DL) from 10 to 100 pg against Cladosporium cladosporioides and C. sphareospermum. In the anticholinesterase (AChE) evaluation, the oils of P. callosum (DL = 0.01 ng) and P. marginatum (DL = 0.01 ng) were one hundred times more potent than the standard physostigmine (DL = 1.0 ng). Molecular docking analysis showed that phenylpropanoids docked reasonably well with acetyleholinesterase and may be responsible for the anti-AChE activities of the Piper EOs. This is the first presentation about acetylcholinesterase inhibition by methylenedioxyphenyl-propanoids.

The chemical compositions have been investigated of the volatile oils of nine populations of six species from Albania, namely Artemisia absinthium, Calamintha nepeta, Hypericum perforatum, Sideritis raeseri subsp. raeseri, Origanum vulgare subsp. hirtum from two wild .populations, and Salvia officinalis (sage) from two wild and one cultivated population,. The essential oils were obtained by hydrodistillation and their analyses were performed by GC-MS. The major constituents were: A. absinthium: neryl isovalerate (19.5%), geranyl isobutanoate (16.4%) and carvacrol (8.8%); C. nepeta: pulegone (31.7%), spathulenol (20.0%) and isomenthone (12.7%); H. perforatum: caryophyllene oxide (31.0%), δ-selinene (10.5%) and carvacrol (10.4%); O. vulgare: carvacrol (81.0, 78.6%), y-terpinene (5.5, 7.1%) and p-cymene (4.9, 4.1%) for 0. vulgare originating from Tepelena. and.Vlora, respectively; S. raeseri: carvacrol (36.7%), caryophyllene oxide (17.8%), p-caryphyllene (8.7%), spathulenol (7.7%) and myrtenol (6.4%); S. officinalis: camphor (40.2, 47.8, 45.9%), c-thujone .(19.2, 22.2, 13.7%), eucalyptol (5.4, 2.6, 6.0%), camphene (5.8, 6.1, 3.9, %), borneol (2.1, 2.9, 5.7%) and bornyl acetate (3.3, 1.4, 5.6%) for samples originating from Tepelena, Tirana and Vlora, respectively. The essential oils were also tested for their free radical scavenging activity using the following in vitro assays: i) interaction with the free stable radical of DPPH (1,1-diphenyl-2-picrylhydrazyl), and ii) inhibition of linoleic acid-peroxidation with 2,2'-azobis- 2-methyl-propanimidamide, dihydrochloride (AAPH). Finally, their inhibitory activity toward soybean lipoxygenase was evaluated, using linoleic acid as substrate.The essential oil of 0. vulgare (OV-VL) presented the highest interaction with the stable radical DPPH (76.5%), followed by that of A. absinthium (54.7%). O. vulgare (OV-TP) and A. absinthium showed high anti-lipid peroxidation activity, 97.5% and 96.5%, respectively, higher than that of the reference compound trolox (73.0%). Only the tested sample of O. vulgare (OV-VL) significantly inhibited soybean lipoxygenase (54.2%).

Essential oils composition of three Tagetes minuta varieties and a wild population (WP) from Argentina and their nematicidal activity against root-knot nematode, Meloidogyne javanica, in vitro and in vivo are described. All T. minuta EOs tested were very active against nematode juveniles (J2), by the strongest nematicidal effects were exhibited by the TmV3 variety oil, characterized by a high content of (E)-ocimenone. High nematode egg hatching suppression (> 90%) was induced by TmV3 EO after five days of incubation. In vivo tests on tomato seedlings showed a significant reduction of infection rate of M. javanica J2 treated with TmV3 and WP oils at sub lethal dose. Therefore, EOs from stables new varieties of T. minuta could be environmentally friendly nematicidal agents. Fil: Massuh, Yamile. Instituto de Ciencias Agrarias; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Cruz Estrada, Angel. Instituto de Ciencias Agrarias; España Fil: Gonzalez Colomba, Azucena. Instituto de Ciencias Agrarias; España Fil: Ojeda, Marta Susana. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina Fil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Andres, Maria Fe. Instituto de Ciencias Agrarias; España

Cinnamomum rigidifolium, Dasymaschalon longiusculum, Fissistigma maclurei and Goniothalamus albiflorus were collected from different landscapes in Vietnam and hydro distilled to produce essential oils with yields from 0.15 - 0.35%. The oils were analyzed by GC-MS-FID and rechecked by measurements on two different instrumentation configurations. The main components of the studied essential oils were for Cinnamomum rigidifolium linalool (19.4%), α-pinene (13.8%), verbenone (9.9%) and cis-verbenol (8.9%), total identified 90.5%; for Dasymaschalon longiusculum spathulenol (21.4%), caryophyllene oxide (17.6%), a-pinene (5.5%) and β-pinene (5.2%), total identified 70.1%; for Fissistigma maclurei spathulenol (17.8%), guaia-6,10(14)-diene-40-ol (10.3%), (E)-β-caryophyllene (7.3%) and caryophyllene oxide (7.0%), total identified 75.3% and for Goniothalamus albiflorus 1,8-cineole (13.2%), α-pinene (10.6%), ledol (7.5%) and caryophyllene oxide (7.3%), total identified 78.0%.

The essential oil (EO) of Lantana montevidensis (Spreng.) Briq. (L. sellowiana LinkOtto) was investigated for its chemical composition and mosquito repellent activity. The essential oil obtained by hydrodistillation of aerial plant parts was analyzed by GC-FID and GC-MS. The major constituents were p-elemene (22.0%), β-caryophyllene (20.1%), and germacrene D (9.4%). Sesquiterpene hydrocarbons were present.in considerable quantities (78.9%) in the L. montevidensis EO, followed by oxygenated sesquiterpenes (8.9%), monoterpene hydrocarbons (7.7%), oxygenated monoterpenes (1.9%), diterpenes (1.2%) and other compounds (0.2%). The oil of L. montevidensis was repellent with a minimum effective dosage (MED) of 0.021 ± 0.013 mg/cm(2) as compared with that of the positive control N,N-diethyl-3-methylbenzamide (DEET) with a MED of 0.006 : 0.001 mg/cm(2)) against Aedes aegypti L. The major compound β-elemene was tested individually for its repellency and had a MED value of 0.23 ? 0.14 mg/cm2 (DEET was 0.008 ? 0.001 mg/cm2). This is the first report on the repellent activity of L. montevidensis EO and P-elemene using human-based in vivo assays against Ae. aegypti.

Components of cinnamon bark, rosemary, clove and thyme essential oils were screened for antioxidant and antibacterial activity utilizing thin-layer chromatography (TLC) coupled with the DPPH(.) test and direct bioautography using Bacillus subtilis cells. The compounds in the active chromatographic zones were identified by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) after their elution. Seven antibacterial components were found: cinnamaldehyde and eugenol in cinnamon bark oil, 1,8-cineole, camphor, borneol and α-terpineol in rosemary oil, eugenol in clove oil and thymol in thyme oil. Only two of them, thymol and eugenol displayed a free radical scavenging effect.

The chemical composition, antioxidant, antimicrobial and insecticidal properties of essential oil obtained by hydro-distillation from Bubonium imbricatum Cav. have been investigated. The essential oil of aerial parts was analyzed by GC-FID and GC-MS. A total of 63 compounds were identified representing more than 82% of the oil. The major components were cis-chrysanthenyl acetate (31.2%) and thymol isobutyrate (3.4%). The antioxidant activity was evaluated by the DPPH and reducing power test. The data showed moderate activity compared with the reference compounds. Our results showed strong activity of the investigated oil against all tested microorganisms. The highest antibacterial activity was observed against Bacillus subtilis (inhibition zone= 18 ± 0.21, MIC= 0.18 mg/mL). In general, Gram-positive bacteria were more susceptible than Gram-negative ones. Candida parapsilosis was the most sensitive among the Candida strains tested. LD50 and LD90 values were 33.1 and 53.1 ppm against 1-d-old larvae of Aedes aegypti L.

The major purpose of this study was to determine the chemical relationships between the essential oils (EO) obtained form 18 mint samples of different species and its cultivrs. GC/MS analysis of all essential oils showed that oxygenated monoterpenoids are the major components of these oils, with the exception of Mentha arvensis 'Banana'. Based on the. chemical composition of the essential oils, the analyzed mints can be divided into five groups. Group I was characterized by the-presence of menthol and menthone, piperitenone oxide is the major constituent of group II, linalool of group III, carvone characterizes group IV, while 3-octanone is the most characteristic compound for group V. A reference strain of biofilm forming Staphylococcus epidermidis ATTC 35984 was tested against the obtained essential oils. Two of them, M suaveolens 'Variegata' and M x piperita 'Almira' exhibited significant bacteriostatic activity. The MIC values of these EOs were 0.25% and 0.5% respectively in comparison with an average MIC of 4% of the other tested mint EOs. Both active EOs are characterized by the presence of piperitenone oxide as the major component.

The in viro antioxidant, anti-inflammatory, anti-hyperglycaemic, and anti-acetylcholinesterase activities of the essential oils (EOs) isolated from six Lamiaceae species (Thymbra capitata,. Thymus albicans, Th. caespititius, Th. carnosus, Th. lotocephalus and Th. mastichina) grown in Portugal, were evaluated. Th. caespititius and T. capitata carvacrol/thymol-rich EOs showed the best capacity for preventing lipid peroxidation, and scavenging the 2,2'-azino- bis(3-ethylbenzothiazoline-6-sulphonid acid) (ABTS) and peroxyl free radicals, as well as for inhibiting lipoxygenase and a-amylase. However, Th. caespititius and Th. lotocephalus 1,8-cineole and linalool rich EOs were the best inhibitors of a-glucosidase. T capitata, Th. lotocephalus and Th. albicans EOs were the: most active for inhibiting acetyleholinesterase. Th. caespititius and Th. mastichina EOs were the main scavengers of nitric oxide (NO) radicals. The comparison between the present data with a survey of the existing literature on the in vitro biological activities of the essential oils isolated from the same species from Portuguese origin, using other.methodologies, showed some differences. For instance the use of two oxidizable substrates (egg yolk andlecithin liposomes) led to distinct results mainly for those samples with relatively low activity. In addition, the EOs capacity for scavenging peroxyl radicals-was also influenced by the presence of cyclodextrins, as a synergism seemed to occur between EOs and those carbohydrates.

Essential oils (EOs) from leaves and branches of Aniba parviflora (Meisn.) Mez were obtained by hydrodistillation and their chemical compositions determined by gas chromatography - mass spectrometry. Oxygenated sesquiterpenoids were the most representative compound class in both EOs (~ 40%). However, the leaf EO was rich in β-phellandrene (15.1%), linalool (14.1%), and y-eudesmol (12.9%). The EO from the branches showed high concentrations of γ-eudesmol (16.8%), β-caryophyllene (15.7%), linalool (12.4%), β-phellandrene (6.7%), and bicyclogermacrene (6.0%). The EOs were screened for radical-scavenging activity using the DPPH assay. In the DPPH assay, the EOs showed an antioxidant activity with TEAC values of 296.8 ± 20.2 and 357.3 ± 43.8 mg.TE.mL⁻¹, about one-third that of the Trolox standard. The EOs were subjected to antibacterial screening and displayed promising activity against Escherichia coli (MIC19.5 μg.mL⁻¹). In addition, the EOs were tested for cytotoxic activity against MCF-7 breast tumor cells and the leaf EO (IC₅₀ = 67.9 ± 3.0 μg.mL⁻¹.) was more active than that from the branches (IC₅₀ = 102.2 ± 3.0 μg.mL⁻¹).

This work presents the first phytochemical investigation of Geranium kikianum Kit Tan & G. Vold (Geraniaceae), a species endemic to the southern Peloponnese, Greece. The essential oil from aerial parts of the plant was isolated by hydrodistillation and its chemical composition characterized by GC-MS. A total of 26 compounds were identified, constituting 98.3% of the oil composition. Oxygenated sesquiterpenes were the main group of constituents (75.4%). The major component of the oil was the sesquiterpene ketone germacrone (45.6%). Eleven alcohols represented the most diverse chemical class in the volatile oil (36.3%), and phytol was the most abundant acyclic diterpene alcohol (11.4%). The volatile compounds and residual water remaining after hydrodistillation were screened for their radical-scavenging activity by the DPPH method. IC 50 values ranged from 0.2±0.03 mg/mL for the undiluted decoction to 69.7±0.5 mg/mL for the essential oil. The significant antioxidant activity of the residual water, comparable with that of the widespread synthetic antioxidant BHT (0.2±0.01 mg/mL), and almost tenfold higher than thymol (1.90 ± 0.04 mg/mL), correlates with a high content of total phenolic compounds (100.2±1.7 mg GAE/g), and flavonoids (11.9±1.2 mg GAE/g).

This study investigated the chemical composition, in vitro cytotoxicity, anti-mildew, and anti-wood-decay fungal activities of the essential oil isolated from the fruit of Liquidainbar formosana from Taiwan. The essential oil from the fresh fruit was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 45 compounds were identified, representing 98.5% of the essential oil. The main components identified were a-pinene (16.8%), β-caryophyllene (10.1%), τ-muurolol (8.3%), τ-cadinol (7.6%), β-pinene (6.7%), and sabinene (5.7%). The essential oil exhibited cytotoxic activity against human oral, liver, and lung cancer cells. The active source compounds were β-caryophyllene, τ-cadinol, and τ-muurolol. The fruit essential oil was shown to have excellent anti-mildew and anti-wood-decay fungal activities, the active compounds being evaluated as τ-cadinol and τ-muurolol.

Roots of wild growing Angelica archangelica L. from Mt. Ozren (Serbia) were subjected to hydrodistillation and GC-MS analysis. The roots contained 0.10% of essential oil with a-pinene (29.7%), 8-3-carene (14.2%), and a mixture of P-phellandrene and limonene (13.2%) as main compounds. The modified resazurin microtiter-plate assay was used to evaluate the antibacterial activity of the essential oil against Staphylococcus aureus and Escherichia coli. The minimum inhibitory concentration (MIC) values were 14.2 μL/mL for S. aureus and 28.4 μL/mL for E. coli, while the minimum bactericidal concentrations (MBC) were 56.8 μL/mL and 113.6 μL/mL, respectively. According to the obtained results, the angelica root essential oil can be applied as a natural preservative in food and as a natural antibiotic for the treatment of several infectious diseases caused by these two bacteria.

The composition of leaf and bark oils of Cinnamosma madagascariensis has been investigated by a combination of GC (RI), GC-MS and ¹³C NMR. The leaf oil contained mainly monoterpenes: myrcene (17.9%), limonene (17.8%), Q-phellandrene (15.3%) and linalool (12.2%). The bark oil, investigated for the first time, contained P-pinene (49.9%) and a-pinene (19.5%) as major components. Special attention was paid to the identification of cyclocopacamphene, an epimer of cyclosativene. 3C NMR data of both compounds have been provided.

The objective of the present study was to characterize chemically the essential oils of two distinct propolis types: Brazilian red and Taiwanese green. Unlike the non-volatile chemical composition of these types of propolis, which has been extensively studied, the knowledge of the essential oils is scarce or even not investigated. The essential oils were obtained by hydrodistillation of raw propolis samples using a Likens-Nickerson type apparatus and then analyzed by GC/MS. The main volatile components of Brazilian red propolis were the phenylpropanoids: elemicin (26.1–27.5%), methyl eugenol (16.3–23.8%), trans-methyl isoeugenol (9.2–11.6%), isoelemicin (6.1–7.1%) and trans-anethole (4.4–7.1%), while the major constituents of Taiwanese green propolis essential oil were: β-eudesmol (13.9%), 6-methyl-3,5-heptadiene-2-one (12.2%), γ-eudesmol (4.4%), geranial (4.1%) and 6-methyl-5-heptene-2-one (3.7%).

Plants yields are influenced by agronomic techniques. Plant density is a complex issue and extremely important when maximizing both crop quality, and biomass and essential oil yields. Plants belonging to the Origanum vulgare subspecies hirtum (Link) Ietswaart were grown adopting four types of plant density and were characterized in biometric and chemical terms. The samples were analyzed using the ANOVA (Principal Component Analysis) statistical method regarding biometric aspects, EO yield and peltate hair density. Essential oil (EO) was extracted by hydrodistillation and analyzed using GC-FID and GC-MS. GC-FID and GC-MS analysis led to the identification of 45 compounds from the EO. Plant density affected production both in terms of biomass and EO. However, it was not found to have affected peltate glandular trichome density or EO quality.

The essential oil from the leaves of Phoebe formosana from Taiwan was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Seventy-one compounds were identified, representing 100% of the oil. The main components identified were a-humulene (16.8%), τ-cadinol (8.9%), α-pinene (8.4%), α-cadinol (8.1%), β-caryophyllene (8.0%), β-phellandrene (6.0%), and β-eudesmol (5.8%). The oil exhibited cytotoxic activity against human lung, liver and oral cancer cells. The active compounds were β-caryophyllene, α-humulene, τ-cadinol, β-eudesmol, and α-cadinol. The antibacterial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against eight bacterial species. The oil exhibited moderate growth suppression against Gram-positive bacteria with inhibition zones of 28 to 36 mm, and MIC values of 250 to 375 μg/mL. The active antibacterial compounds were determined to be τ-cadinol, β-eudesmol, and α-cadinol. The leaf oil displayed excellent antifungal activity with the active compounds determined as α-cadinol, β-eudesmol, τ-cadinol, α-humulene, and β-caryophyllene.

The chemical composition and antibacterial activity of Dittrichia graveolens (L.) Greuter essential oil were examined. Gas chromatography and gas chromatography/mass spectrometry were used to analyze the chemical composition of the essential oil. The antibacterial activity was investigated by the broth microdilution method against thirteen bacterial strains. The interactions of the essential oil and three standard antibiotics: chloramphenicol, tetracycline and streptomycin toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods: principal components analysis and hierarchical cluster analysis. Oxygenated monoterpenes were the most abundant compound class in the essential oil (40.6%), with bomyl acetate (21.7%) as the major compound. The essential oil exhibited slight antibacterial activity against the tested bacterial strains in vitro, but the combinations D. graveolens essential oil-chloramphenicol and D. graveolens-tetracycline exhibited mostly synergistic or additive interactions. These combinations reduced the minimum effective dose of the antibiotics and, consequently, minimized their adverse side effects. In contrast, the association of D. graveolens essential oil and streptomycin was characterized by strong antagonistic interactions against E. coli ATCC 25922, S. aureus ATCC 29213 and P. aeruginosa ATCC 27853. In the principal components analysis (PCA) and hierarchical cluster analysis (HCA), streptomycin against these bacterial strains stood out and formed a separate group.