Analysis Of Leaf Oils Research Articles

Variation in plant morphology and leaf essential oil composition of a representative <em>Cinnamomum verum</em> collection from Sri Lanka

Sri Lankan cinnamon germplasm is an underexploited genetic resource of high breeding potential. A representative collection of a cultivated cinnamon germplasm with 48 accessions, is established at the University of Ruhuna, Sri Lanka. From that collection, 40 three-year-old vegetative-propagated accessions, were used in this study to study the variations in plant morphology and leaf oil composition. Flush colour was determined as four main categories of pink, red, brown, and green in all 48 accessions. Leaf length, leaf width, leaf length to width ratio and petiole length varied from 7.9 to 14.5 cm, 3.8 to 7.3 cm, 1.8 to 3.07 cm, and 1 to 2.2 cm, respectively, in the selected 40 accessions. Both the good fragrant aroma category of bark fragrance and the sweet pungent category of bark taste were recorded in 21 of the 40 accessions. Twenty (20) accessions from above collection were selected for leaf oil analysis. Gas chromatography-mass spectrometry (GC-MS) of leaf oil revealed the presence of 146 chemical compounds. Eugenol was the major compound of 17 accessions (52.2% to 79.5%). Two accessions with zero eugenol contained 86.8% and 91.9% of benzyl benzoate (BB), in contrast to that of 0%-0.65% from other accessions. One accession produced 16.6% eugenol and 22.3% BB. A green flush colour associated with a higher BB percentage suggested a potential morphological marker for BB. The PCA for 20 accessions explained 88.11% of total variance. The cinnamon accessions with high BB, KA11 and GB17, were clustered together, and HB12 was isolated on a different cluster. Positive correlations were detected between linalool and β-caryophyllene (0.649), linalool and BB (0.770) (p < 0.01), and negative correlations between eugenol and linalool (-0.630) and eugenol and BB (-0.886) (p <0.01).

Antifungal activity of essential oil and its constituents from Calocedrus macrolepis var. formosana Florin leaf against plant pathogenic fungi

Resistance to conventional fungicides causes the poor disease control of agriculture. Natural products from plants have great potential as novel fungicide sources for controlling pathogenic fungi. In this study antipathogenic activity of the leaf essential oil and its constituents from Calocedrus macrolepis var. formosana Florin were evaluated in vitro against six plant pathogenic fungi. Chemical analysis of leaf oil by GC/MS allowed identification of α-pinene (44.2%), limonene (21.6%), β-myrcene (8.9%), β-caryophyllene (8.2%), caryophyllene oxide (2.4%), α-cadinol (1.6%), β-pinene (1.2%), and T-muurolol (1.1%) as main components. Sesquiterpenoid components of the oil were more effective than monoterpenoid components of the oil. In particular, T-muurolol and α-cadinol strongly inhibited the growth of Rhizoctonia solani and Fusarium oxysporum, with the IC 50 values < 50 μg ml −1. These compounds also efficiently inhibited the mycelial growths of Colletotrichum gloeosporioides, P. funerea, Ganoderma australe and F. solani. These results showed that T-muurolol and α-cadinol possess antifungal activities against a broad spectrum of tested plant pathogenic fungi and could be used as potential antifungal agents for the control of fungal diseases in plants.

GC and GC/MS Leaf Oil Analysis of Four Algerian Cypress Species

The leaf oils of four Cypress species growing in Algeria were examined by GC and GC/MS. In total 76 constituents were identified, from which 49, 46, 48 and 54 compounds were found in the oils of Cupressus glabra Sudw., C. arizonica Greene, C. sempervirens L. and C. dupreziana Camus. The main components of the oils were: C. glabra: terpinen-4-ol (10.5%) and umbellulone (27.4%); C. arizonica: α-pinene (10.5%) and umbellulone (37.3%); C. sempervirens: α-pinene (2.8–44.9%), δ-3-carene (31-10.6%) and α-terpinyl acetate (5.5–12.0%) and C. dupreziana: α-pinene (36.4%) and δ-3-carene (33.8%).

Analysis of leaf oils from a Eucalyptus species trial

The volatile leaf oils were analysed from adult leaves of five Eucalyptus species growing in a common environment. The trial consisted of two provenances of the species E. globulus and one provenance each of E. nitens and E. denticulata from the southern blue gum group and two provenances each of the species E. delegatensis and E. regnans from the ash group. Oil yields from adult leaves of E. nitens (0.7% dry wt.) and E. denticulata (0.8%) were markedly lower than those from the other three species (3.0–6.1%). Volatile leaf oils of E. delegatensis and E. regnans were rich in α- and β-phellandrene, cis- and trans- p-menth-2-en-1-ol, while E. regnans was also rich in α-, β- and γ-eudesmol. In contrast, volatile leaf oils of E. globulus were rich in 1,8-cineole and α-pinene and E. denticulata rich in γ-terpinene and p-cymene. Oil composition of E. nitens was intermediate between E. globulus and E. denticulata. Differences in oil yield and oil composition between species indicated a strong genetic basis for these variables.

Simplified Method of Volatile Leaf Oil Analysis for Identification of Citrus Cultivars

Volatile oils were extracted from aqueous leaf suspensions of sweet orange [Citrus sinensis (L.) Osb.] cultivars Hamlin, Navel, and Valencia and grapefruit (Citrus paradisi Macf.) cultivars Marsh and Ray Ruby. Pressurized air was used as the sparging gas, and volatile oils were collected in a C-18 cartridge. Gas-liquid chromatography was used to separate and quantify 17 volatile components. Significant quantitative differences for individual components made it possible to distinguish sweet orange from grapefruit (four components), `Marsh' from `Ray Ruby' grapefruit (two components), `Hamlin' from `Valencia' or `Navel' orange (six components), and `Valencia' from `Navel' (three components). The simplicity and sensitivity of the procedure suggest potential use for Citrus taxonomic, genetic, and breeding research.

Analysis of leaf oils from four varieties of sweet orange by combined gas chromatography‐mass spectrometry

AbstractThe leaf oil of four varieties of Algerian sweet orange were examined by GC and GC‐MS. In total, 68 constituents were identified from which 50, 54, 38 and 43 compounds were found to be present in the leaf oils of Washington‐navel, Valencia, Sanguine and Portuguese varieties respectively. Of the 68 constituents, 34 were characterized in sweet orange leaf oil for the first time.

Volatile leaf oil analysis in chemosystematic studies of North American conifers

The chemosystematic results based on leaf oil analysis of northern North American conifers of the families Pinaceae and Cupressaceae are summarized and discussed in relation to known botanical relationships and other chemosystematic approaches. Quantitative leaf oil analysis provides excellent data for use at the species and subspecies taxonomic levels.

Chemosystematic studies in the genus Abies. I. Leaf and twig oil analysis of alpine and balsam firs

The volatile oils of the leaves and twigs of alpine fir, and western and eastern Canadian balsam fir were analyzed by gas–liquid chromatography. Many qualitative similarities were found and the within-tree and tree-to-tree variation of the quantitative terpene composition of the leaf oil was sufficiently small to permit a chemosystematic study. Abies lasiocarpa and A. balsamea may be differentiated by the relative amounts of β-pinene, 3-carene, β-phellandrene, trans-ocimene, piperitone, methyl thymol, and thymol. Consistent quantitative differences were also found between eastern and western A. balsamea, and the populations in the Lesser Slave Lake and Battle Lake regions of central Alberta gave intermediate terpene data, which suggests introgression between A. lasiocarpa and western A. balsamea. Thus a cline between A. lasiocarpa and A. balsamea, with western balsam fir populations as bridge, may have existed after the last glaciation. The alpine fir populations of southern Alberta, and eastern and central British Columbia gave uniform terpene data, but five trees sampled on Green Mountain, Vancouver Island, gave significantly different terpene data. These results were substantiated by morphological characters as well as twig oil analysis, but the latter two methods gave less consistent data than leaf oil analysis.

Chemosystematic Studies in the Genus Pseudotsuga. III: Population Differences in British Columbia as Determined by Volatile Leaf Oil Analysis

Detailed analysis of the volatile leaf oil terpenes of different Douglas-fir populations and provenances growing in British Columbia confirmed the previous classification into the following terpene types: three coastal (A, B, and C), coastal intermediate, intermediate, interior intermediate, and Rocky Mountain. In areas of overlap of the coastal and Rocky Mountain varieties a continuous gradation of terpene types may be encountered. Differences in elevation or soil sites within homogeneous populations do not affect the terpene patterns noticeably. The major area of overlap occurs in the Cascade Mountains of southern British Columbia. Further inland either interior intermediate or Rocky Mountain types are found. However, at wet sites there is a noticeable increase of the typical coastal terpenes. Conversely, at drier sites in the southern coastal regions, including southeastern Vancouver Island, a distinct increase of the typical Rocky Mountain variety terpenes was recorded. Somewhat unexpectedly, this was also found at Cowichan-Skutz, which is a typical wet coastal site. Equally unexpected was the finding of many trees with the coastal C terpene pattern in three locations near D'Arcy; no noticeable increase in the typical Rocky Mountain variety terpenes was recorded at D'Arcy.A simplified gas chromatographic technique was developed which reduces the cost of analysis by a factor of ten, yet allows differentiation between the seven terpene types.

Chemosystematic studies in the genus Pseudotsuga. I. Leaf oil analysis of the coastal and Rocky Mountain varieties of the Douglas fir

The volatile leaf oils of the coastal and Rocky Mountain varieties of the Douglas fir were found to have distinctive terpene compositions. The relative amounts of l-β-pinene, sabinene, 3-carene, α- and γ-terpinene, terpinolene, l-terpinen-4-ol, citronellol, citronellyl and geranyl acetate (relatively large in the former variety); and santene, tricyclene, l-camphene, limonene, and l-bornyl acetate (relatively large in the latter variety) may serve as distinguishing features. n-Hexenal, l-α-pinene, α- and β-phellandrene, linalool, fenchyl alcohol, and l-α-terpineol were also isolated. The within-tree and within-population variation of the amounts of these terpenes as well as populational differences from Calgary through the foothills to Revelstoke were small. Intermediate compositions were encountered as far west as the Cascades and one may distinguish clearly between interior and coastal intermediate terpene patterns. Between Keremeos and Hedley the terpene pattern was essentially that of the Rocky Mountain variety whereas at Jasper intermediate patterns leaning towards coastal intermediates were recorded. Analysis of the leaf oils from five different provenances of coastal populations indicated that a north–south cline may exist. Provenance samples showed conclusively that the terpene patterns are genetically controlled and are not influenced by ecological factors. Hence these terpene patterns may serve as a genetic guide and provide a quantitative measure of coastal, intermediate, and Rocky Mountain types of populations.

Gas–liquid chromatography of terpenes. Part XVIII. The volatile oil of the leaves of Juniperus communis L.

The volatile leaf oil of the local common juniper was found to consist mainly of α-pinene (73 to 83%) and smaller amounts (0.5 to 5%) of β-pinene, 3-carene, myrcene, limonene, methyl citronellate, bornyl acetate, myrtenal, myrtenol, myrtenyl acetate, α-terpineol, citronellol, citronellyl acetate, nerolidol, farnesol, and an unusual hydroxy ketone. Of the many trace constituents, β-phellandrene, citronellal, "iso-" citronellal, linalool, geraniol, isopulegol, 4-terpinenol, and ε-cadinene were isolated, whereas camphene, sabinene, α-phellandrene, γ-terpinene, terpinolene, p-cymene, fenchone, thujone, isothujone and δ-cadinene could only be tentatively identified.There was little variation in the quantitative composition of the leaf oil from one plant to another. Since the composition of this oil differs significantly from that of other juniper leaf oils, chemotaxonomic studies by means of leaf oil analysis are feasible.