Foliage Oils Research Articles

GC/MS quantification of individual fatty acids of selected green leafy vegetable foliage and their biodiesel attributes

The current demand for edible vegetable oil is increasing worldwide, and the development of new sources of high-quality vegetable edible oil is an essential task. There is also a huge demand for biodiesel in domestic and industrial applications, and foliage oils could be a good source for diesel applications. The current study aimed at the identification and quantification of fatty acids from commonly consumed green leafy vegetables (GLVs) viz., Hibiscus cannabinus, Hibiscus sabdariffa, Basella alba, Basella rubra, and Rumex vesicarius and to calculate the biodiesel attributes of the oil. The total oil content was ascertained as the highest in R. vesicarius foliage (3.91 ± 0.27 g/100 g dry leaf powder). GC/MS chromatographic investigation identified 9,12,15-octadecatrienoic acid as a significant compound followed by hexadecanoic acid. In Hibiscus spp. C18:3 (49.3 µmol % and 50.4 µmol %) was recorded to be the most noteworthy followed by C16:0 (23.2 µmol % and 21 µmol %) in H. cannabinus and H. sabdariffa, respectively. The GLVs foliage-fatty acid biodiesel attributes were additionally assessed through an empirical formula. Consequently, the overall examined results will be helpful for the investigation of these oils as vegetable oil for human consumption and biodiesel applications.

Seasonal variations of essential oil content and composition in male and female plants of Juniperus communis L. ssp. hemisphaerica growing wild in Iran

The foliage essential oils (obtained by hydro-distillation) of male and female plants of Juniperus communis L. subsp. hemisphaerica, collected from wild habitat were estimated in three different seasons (spring, summer and autumn). The highest essential oil content was obtained from male plants in spring (3.40%). GC and GC/MS analysis of foliage oils showed that the monoterpenes (77.1–88.7%) were the major groups of compounds, followed by amount of sesquiterpenes (4.3–6.3%). The major constituent of the both male and female foliage oils in spring and autumn was α-pinene. In the samples collected during summer, essential oil was dominated by α-pinene (48.8%) and sabinene (44.5%) for male and female plants, respectively. The concentration of α-pinene in the foliage oils from the male plants was higher than in the oils from the female plants. In the present experiment, the variations chemical composition of essential oil were mainly due to the differences in type of the foliage (extracted from male or female plant) and harvest season. In conclusion, foliage of J. communis L. subsp. hemisphaerica for obtaining higher essential oil content (3.40%), α-pinene (61.69%) and limonene (13.56%) should be collected from male plant during the spring season (or at the flowering stage).

Effect of age of plantation and season on leaf yield, content and composition of oil ofEucalyptus citriodoraHook. and soil properties in semi-arid conditions of Karnataka

Age of plantation and season of harvest of Eucalyptus citriodora are important to derive essential oil with proper chemical composition. The studies were conducted to understand the influence of these factors on foliage yield and oil content and composition and also soil properties in some commercial plantations of E. citriodora in a semi-arid region of Karnataka, India. Leaf yield of E. citriodora was significantly higher in >10 years old plantations compared to 5–10 and 5 years old and rainy season harvested leaf (2.54%). Oil content was low when temperature was high during November to March (2.47%). At this condition, the major chemical constituents of oil were citronellal (79.7 to 83.2%) and citronellol (5.5 to 6.7%). Concentration of citronellal decreased during rainy seasons (80.04%) as compared to winter (81.75%) and summer (81.16%). Age of plantation had significant effect on soil quality parameters; as the age of plantation increased available P, K, OC, Ca, Mg, Cu, Mn, Fe and B content decreased, whereas available N, S and Zn contents increased. Soil pH of E. citriodora plantations (5.86–6.60) increased over open area (5.07). To harvest high yields with good quality foliage of E. citriodora, soil fertility management needs attention to replenish some plant nutrients.

Potential for Using Essential Oils to Protect Viscoelastic Thermal Compression–Treated Hybrid Poplar

Abstract The potential for using pretreatment with cinnamon leaf oil or juniper foliage oil to improve the durability of viscoelastic thermal compression (VTC)–treated hybrid poplar was explored in a field termite test and a laboratory mold test. The addition of oils prior to VTC processing had variable effects on resistance to both mold and termite attack. Subsequent gas chromatography–mass spectroscopy assessment of residual oil components in VTC processed material suggested that the heating associated with the process was associated with substantial degradation of oil components that might help explain the lack of protective effect. The results suggest that further attempts to use essential oils to improve the durability of VTC processed materials must first explore less aggressive heating conditions to reduce the potential for thermal degradation of oil components while still achieving the attractive gains in physical properties associated with the process.

Drugs based on natural compounds: recent achievements and future perspectives

In recent years, despite enormous efforts to develop new drugs by sophisticated approaches, there has also been a trend for rediscovery of natural products uses. In this context, new metabolites with unusual chemical structures and promising biological and pharmacological properties have inspired chemists in their synthetic approach searching for more potent and selective drugs. At the same time, the increasing awareness on prevention of common diseases such as atherosclerosis and cancer suggested an improvement of life style, including better diets by consumption of natural foods. These topics have been the focus of the Conference on Natural Products in Cancer Prevention and Therapy, 2nd Edition, a meeting hosted by the University of Naples ‘‘Federico II’’ on behalf of the Phytochemical Society of Europe. As chairman of the organizing committee, I have been very honoured and pleased by the large participation of over 120 scientists from 25 countries, not limited to Europe, but including also Africa, America and Asia. The aim of the congress was the presentation of recent results and the exchange of ideas in the field of natural products in cancer prevention and therapy, but also the discussion of new trends and general aspects of research in phytochemistry and medicinal chemistry. Higher plants continue to be the source of many new drugs used for a variety of diseases. This important matter has been discussed by Kinghorn and co-workers involved in a collaborative multi-institutional project directed towards the discovery of new antitumor agents. In their paper, opening this special issue, the isolation and characterization of new secondary metabolites from tropical plants is described together with data regarding their activity and selectivity for cancer cells. Some of these natural product lead candidates, discovered through bioactivity guided fractionation, are proposed as scaffolds for synthetic modifications to develop new potential anticancer agents. The article by Roussis and co-workers reports on the analysis of 46 different Pinus species, affording the identification of 161 metabolites, mainly volatiles, from the pine foliage oils. The work is a representative example of traditional extensive phytochemical research consisting of a comparative metabolomic characterization of plants aimed to find new compounds of potential pharmaceutical interest. Recent epidemiological studies reported that an increase of consumptions of Allium species reduce the risk of prostate and gastric cancers. This could be related to two main classes of compounds: the apolar sulfur compounds and the polar saponins, the latter being pungent and more stable during cooking. On this base, the third contribution by Lanzotti et al. reviewed the literature about the major volatile and non-volatile organic compounds of garlic and other Allium plants V. Lanzotti (&) Dipartimento di Agraria, University of Naples Federico II, Via Universita 100, 80055 Portici, Naples, Italy e-mail: lanzotti@unina.it

Chemical composition and antibacterial activity of foliage and resin essential oils of Araucaria cunninghamii Aiton ex D.Don and Araucaria heterophylla (Salisb.) Franco from India

The essential oils of foliage and resin of Araucaria cunninghamii Aiton ex D.Don and Araucaria heterophylla (Salisb.) Franco were isolated by hydrodistillation and subsequently analyzed using gas chromatography (GC/FID) and GC–mass spectrometry (GC/MS). Altogether 113 constituents, representing 84.0–97.6% of the total oil compositions were identified. Major constituents of the foliage oil of A. cunninghamii were beyerene (34.6–44.4%), caryophyllene oxide (0.5–17.9%), α-pinene (3.3–16.2%), germacrene D (0.1–9.8%), kaurene (1.7–5.1%), and 13-epi-dolabradiene (4.2–4.8%). However, the resin oil of A. cunninghamii was characterized by higher amounts of (E)-caryophyllene (60.8%), caryophyllene oxide (13.4%), and (E)-β-farnesene (4.9%). The foliage oil of A. heterophylla was dominated by 13-epi-dolabradiene (42.7%), beyerene (22.2%), rimuene (13.7%), and dolabradiene (3.9%), whereas the resin oil of A. heterophylla contained α-copaene (29.9%), germacrene D (21.4%), γ-gurjunene (9.7%), δ-cadinene (7.1%), and sandaracopimara-8(14),15-diene (6.5%) as main constituents. The foliage and resin essential oils of both species showed minimum inhibitory concentration (MIC) in the range of 250–500μg/mL and minimum bactericidal concentration (MBC) in the range of 1000 to >1000μg/mL against tested bacterial strains.

The genus Pinus: a comparative study on the needle essential oil composition of 46 pine species

The fresh needles of 46 pine species, including 37 and 17 taxa of the subgenera Pinus and Strobus, respectively, were subjected to hydrodistillation and the essential oils obtained were analyzed by means of GC–FID and GC–MS. The comprehensive analyses of the needle oils, which allowed for the identification of 161 constituents comprising the majority of the volatiles, showed significant, not only quantitative, but also qualitative differences between the samples. Monoterpenes, sesquiterpenes and diterpenes dominated the pine foliage oils, with the presence of the monoterpene hydrocarbons α- and β-pinene and the sesquiterpene hydrocarbon germacrene D characterizing most of the oils. This is the first report on the chemical composition of the essential oils of 21 pine taxa, including 15 taxa of subgenus Pinus and 6 taxa of subgenus Strobus.

Antifungal Activities of Four Cedar Foliage Oils to Wood Stain or Decay Fungi

Antifungal activities of essential oils have been extensively studied and these materials have the potential to replace synthetic biocides. In this study, the chemical composition of Leyland cypress (× Cupressocyparis leylandii), Monterey cypress (Cupressus macrocarpa), Western juniper (Juniperus occidentalis), and Port Orford cedar (Chamaecyparis lawsoniana) foliage oils were determined and their antifungal activities on wood were analyzed. GC-MS analysis showed that monoterpenoids represented more than 90 percent of the oils except Port Orford cedar oil, where monoterpenoids comprised only one third of the oil. Cedar oils were reduced the growth of selected mold fungi and were capable of some inhibition of decay fungi, but could not completely protect wood from stain or decay fungi.

Effects drying and harvest season on the essential oil composition from foliage and berries of Juniperus excelsa

The volatile constituents of the foliage and berries (female cones) of Juniperus excelsa trees from Iran were analyzed by GC and GC–MS. Twenty six constituents were identified and quantitated. Considerable seasonal variation was found in the berry oils, in contrast with the foliage oils. The oil yields in berries increased by 162% from spring to autumn as the berries matured. The amount of α-pinene decreased in the foliage oil during the summer; however it increased in the berry oil. Seasonal variation of other constituents showed various patterns. Seasonal variation in the berry oil was much greater than in the foliage oil. A comparison of oils from fresh vs. dried foliage and berries revealed changes in the amounts of several constituents. α-Pinene decreased after drying, whereas the amounts of several other constituents in the foliage and berry oils increased. This study shows that for the industrial utilization of J. excelsa berry oils, the harvesting period is a critical factor. However, either fresh or dried foliage can be utilized for leaf oil production.

Acute aquatic toxicity of western juniper (Juniperus occidentalis) foliage and Port Orford cedar (Chamaecyparis lawsoniana) heartwood oils

Recently, interest has developed for using essential oils from Western juniper (Juniperus occidentalis) foliage and Port Orford cedar (Chamaecyparis lawsoniana) heartwood in commercial products such as pest repellents and cosmetics. In order to gauge the relative toxicological risk that these oils pose to freshwater and marine organisms, the acute aquatic toxicity of these oils was evaluated using OPPTS guidelines to the cladoceran Daphnia magna, the rainbow trout Oncorhynchus mykiss and the green alga Selenastrum capricornutum. For western juniper foliage oil, no toxicity was exhibited toward D. magna or O. mykiss, even at 5.0 mg/L (the highest concentration tested and limit of solubility). For toxicity to S. capricornutum using algal cell density, the 72 and 96 h EC50 value was 1.7 mg/L and the no observable effect concentration (NOEC) was 0.63 mg/L. For Port Orford cedar heartwood oil, no toxicity was exhibited toward O. mykiss or S. capricornutum, even at 5.0 mg/L (the highest concentration tested and limit of solubility). The 48-h D. magna EC50 value was 1.9 mg/L; the NOEC values for algal cell density were 1.25 mg/L (72 h) and 0.63 mg/L (96 h). In summary, this study shows that western juniper foliage and Port Orford cedar heartwood oils demonstrate little to no risk to aquatic organisms.

The effect of water deficit stress on the growth, yield and composition of essential oils of parsley

Three parsley cultivars (plain-leafed, curly-leafed and turnip-rooted) were grown under conditions of 35–40% and 45–60% water deficit in order to evaluate the effect of this form of stress on plant growth, essential oil yield and composition. Plant growth (foliage and root weight, leaf number) was significantly reduced by water stress, even at 30–45% deficit. Water stress increased the yield of essential oil (on a fresh weight basis) from the leaves of plain-leafed and curly-leafed, but not turnip-rooted, parsley. However, on a m 2 basis foliage oil yield increased significantly only in curly-leafed parsley. Water stress also caused changes in the relative contribution of certain aroma constituents of the essential oils (principally 1,3,8- p-menthatriene, myristicin, terpinolene + p-cymenene), but these changes varied between cultivars. The oil yield of roots was low and water deficit stress had relatively little effect on the root oil composition. It is concluded that because the biomass of plants subjected to water deficit is reduced, it is possible to increase the plant density of plain-leafed or curly-leafed parsley, thereby further increasing the yield of oil per m 2. However, the application of water deficit stress to parsley essential oil production must also take into account likely changes in oil composition, which in turn relate to the cultivar.

Enantiomers of sesquiterpene and diterpene hydrocarbons inAraucaria species

The enantiomeric composition of sesquiterpene and diterpene hydrocarbons in the foliage oils of three different Araucaria species was investigated by enantioselective gas chromatography. Enantiomeric mixtures were observed in both the sesquiterpene and diterpene series. The application of enantioselective gas chromatography for stereochemical analysis of diterpenes is demonstrated. In addition to diterpene hydrocarbons, both enantiomers of manoyl oxide, 13-epi-manoyl oxide and sclareol could be separated by capillary gas chromatography using cyclodextrin derivatives as chiral stationary phases. Copyright © 2000 John Wiley & Sons, Ltd.

Foliage Oil Terpenes ofPrumnopitys ferruginea(D. Don) Laubenf. Variation in Acorenone Levels

ABSTRACT Examination of the foliage oils of 25 specimens of Prumnopitys ferruginea identified ten sesquiterpene hydrocarbons (δ-elemene, α-cubebene, α-copaene, β-cubebene, germacrene-D, β-selinene, bicyclogermacrene, germacrene-A, δ-cadinene and γ-cadinene), the rare sesquiterpene ketone, acorenone, seven diterpene hydrocarbons (rimuene, beyerene, pimaradiene, sandaracopimaradiene, phyllocladene, kaurene and abietatriene) and a diterpene alcohol (Sβ-hydroxyisopimarene). Terpene levels were highly variable. β-Elemene, cis-calamenene and cadina-1,4-diene were detected as artefacts of aging of extracts. Some of the components showed antimicrobial activities against Bacillus subtilis and Trichophyton mentagrophytes, and cytotoxic activity against monkey kidney cells.

Terpenes of foliage oils from Halocarpus bidwillii

A study of the foliage oils of 24 specimens of Halocarpus bidwillii revealed considerable infraspecific variation. The compounds identified comprised two monoterpene hydrocarbons (α-pinene and myrcene), six sesquiterpene hydrocarbons (α-longipinene, longifolene, caryophyllene, germacrene-D, bicyclogermacrene and δ-cadinene), three oxygenated sesquiterpenes (longicamphenylone, spathulenol, and t-cadinol), six diterpene hydrocarbons [8α-isopimara-9(11),15-diene, sclarene, isophyllociadene, isokaurene, phyllocladene and kaurene] and one oxygenated diterpene (kaur-16-en-19-al). Marked differences between the constitution of the mature and juvenile foliage were noted.

Foliage sesquiterpenes and diterpenes of Podocarpus spicatus

Investigation of the foliage oils of 49 specimens of P. spicatus has shown marked infraspecific variation. Seven sesquiterpene hydrocarbons (δ-elemene, α-copaene, longifolene, germacrene-D, bicyclogermacrene, δ-cadinene and selina-4(14),7(11)-diene), two oxygenated sesquiterpenes (curzerenone and atractylon), ten diterpene hydrocarbons (rimuene, beyerene, sclarene, rosadiene, pimaradiene, sandaracopimaradiene, isopimara-7,15-diene, isopimara-8,15-diene, phyllocladene and kaurene), and two oxygenated diterpenes (8β-hydroxyisopimarene and ferruginol) have been isolated and identified. Of particular interest is the isolation of (+)-germacrene-D and (−)-δ-cadinene, along with the rarely reported curzerenone, atractylon, and (+)-rosadiene. This is the first report of selina-4(14),7(11)-diene in an optically active form. The occurrence of both enantiomers of sandaracopimaradiene is also of interest. The biosynthetic significance of correlations in the levels of the terpenes present is discussed.

Terpenes of ponderosa pine and feeding preferences by pocket gophers

Yield and composition of essential oils were compared in foliage, stems, and roots of ponderosa pine seedlings, and preferences for the trees by pocket gophers were determined. Test seedlings represented nine widely separated provenances in the western United States. Seed source of the trees influenced gopher feeding preferences and resulted in varied tree damage. The damage ranged from 0 to 31%, suggesting that some sources might possess sufficient natural resistance to give trees practical protection from gophers in the field. There were no morphological differences among sources to explain differential tree damage. All sources contained essential oils in all tissues examined, but oil yield varied among and within tissue types. Oils were predominantly (76-97%) composed of monoterpene hydrocarbons. Oil composition varied by source, and different tissue types varied greatly in the yield and composition of their oils. Neither yield nor constituents of foliage oils were significantly correlated with gopher damage (or preference). In contrast, some components of stem and root oils were strongly related to preference. Results of correlation and discriminant analyses showed that some oil constituents could serve as indicators of resistance (or susceptibility) to gopher damage. Such important chemical variables, when verified, could be used in selections for ponderosa pine resistant to gophers.

Behavior ofTetranychus urticae toward essential oil mixtures from strawberry foliage

A standard essential oil mixture (SEOM) was formulated containing volatile compounds in the relative proportions found in the essential oil of the foliage of “Citation,” a strawberry cultivar relatively resistant toTetranychus urticae. Other mixtures contained varied levels, relative to the SEOM, oftrans-2-hexen-1-ol, nonanal, α-terpineol, and methyl salicylate. The behavior ofT. urticae females in response to these mixtures at several concentrations in propylene glycol was studied in choice tube (preference) tests. Feeding effects were measured by incorporating the mixtures and individual components into sucrose with32P. In the choice tube tests, mites were generally attracted by mixtures at concentrations of 0.1% or below unless the level of methyl salicylate was below 0.5 × that in the SEOM, or the level of nonanal was above that of the SEOM. When mixtures were incorporated into food, methyl-salicylate-stimulated feeding and nonanal levels were inversely related to the amount of food ingested.

Variability in the essential oils of wood and foliage of Pinus aristata and Pinus longaeva

Variations in the monoterpenoid composition of the essential oil of wood, and of the mono- and sesquiterpenoids of foliage collected from more than 200 specimens of pines of subsection Balfourianae (P. aristata, P. longaeva and P. balfouriana) substantiate the previously reported morphological and chemical separation of P. aristata and P. longaeva and suggest a restricted intermediacy in northern Arizona and eastern California. On the basis of wood essential oil the limited population of P. aristata in northern Arizona, while exhibiting to a slight degree morphological intermediacy, is found to be practically identical to the main populations of P. aristata in Colorado and New Mexico. On the basis of foliage oil, however, the same population is clearly intermediate, but closer to P. aristata. The detailed chemical data suggest a distinct chemical status for the Arizona population, with selection for the present-day chemophenotypes being the dominant factor in their evolution. Analysis of monoterpenoids from P. balfouriana × longaeva hybrids indicates that incomplete selective elimination of 3-carene-producing P. longaeva chemophenotypes rather than gene exchange with P. balfouriana is responsible for the presence of abnormal P. aristata-like 3-carene-producing trees in eastern California. The latter trees could have resulted from limited gene exchange between P. aristata and P. longaeva by routes no longer available to them lying to the south of the Grand Canyon.

Chemosystematic studies of the volatile oils of Juniperus horizontalis, J. scopulorum and J. virginiana

The volatile oil from the foliage of individual plants from different populations of Juniperus horizontalis, J. scopulorum and J. virginiana has been analyzed qualitatively and quantitatively. Some analytical problems are discussed and several new constituents have been identified. J. horizontalis can be differentiated from the other two species by the presence of relatively large percentages of cadinane-type sesquiterpenes and less of the elemol-eudesmol type. The ratio of methyl citronellate to citronellol may also have diagnostic value, as may be the virtual absence of aromatic ethers of the safrole-type. The oil of J. scopulorum is virtually devoid of the cadinol type sesquiterpenes but differentiation from that of J. virginiana is difficult. A useful measure of clinal variation within different populations of each species is the ratio of sabinene and limonene percentages. The occurrence of aromatic ethers in J. scopulorum and J. virginiana is erratic; in J. horizontalis they are present in trace amounts only. Provided an adequate foliage sample size is taken during the dormant season, population studies based on the means of the percentages of the foliage oil components are feasible. Two hybrid swarms of J. horizontalis and J. scopulorum were sampled and all plants had intermediate foliage oil compositions.

1,2-Dihydro-1,1,6-trimethylnaphthalene from strawberry oil

1,2-Dihydro-1,1,6-trimethylnaphthalene (3,4-dehydroionene) has been identified in the essential oil of strawberry fruit and foliage.