Hydrocarbon Distribution in Epicuticular Waxes of Five Euphorbia Species

1996 ◽  
Vol 51 (5-6) ◽  
pp. 291-295 ◽  
Author(s):  
Waqar Ahmad ◽  
Muhammad Nazir ◽  
Faqir Mohammad Chaudhary ◽  
Ashfaq Ahmad
Keyword(s):  
Distribution Pattern ◽  
Homologous Series ◽  
Epicuticular Waxes ◽  
Surface Waxes ◽  
Branched Chain ◽  
Hydrocarbon Distribution

Abstract The distribution pattern of hydrocarbons in the surface waxes of five species of Euphor­ biaceae, E.caducifolia, E.helioscopia, E.milii, E.royleana and E.tirucalli was studied. In addi­tion to homologous series of n-alkanes, minor quantities of unsaturated and branched hy­drocarbons were also detected. Some of the branched chain hydrocarbons could be explained as having originated from isoprene units and the substituents corresponding to diterpenes and triterpenes.

n-Alkanes -Common Surface Constituents of Pollen from Gymno-and Angiosperms

1990 ◽  
Vol 45 (11-12) ◽  
pp. 1090-1092 ◽  
Author(s):  
Susanne Hagenberg ◽  
Klaus Wehling ◽  
Rolf Wiermann
Keyword(s):  
Homologous Series ◽  
Distribution Patterns ◽  
Lipid Classes ◽  
Surface Waxes ◽  
Angiosperm Pollen

Abstract The surface waxes of several gymnosperm and angiosperm pollen were separated into different lipid classes. n-Alkanes were found to be common constituents of these waxes. They appeared as a homologous series ranging from C20 to C33. The distribution patterns of n-alkanes from gymnosperm pollen displayed little variation whereas those of angiosperm pollen exhib­ited pronounced differences from one another. It is noteworthy that especially for the gymno­sperm species, homologues with even and odd numbers of carbons occurred in similar amounts.

scholarly journals Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes

2016 ◽  
Vol 16 (12) ◽  
pp. 7813-7823 ◽  
Author(s):  
Johanna Joensuu ◽  
Nuria Altimir ◽  
Hannele Hakola ◽  
Michael Rostás ◽  
Maarit Raivonen ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Epicuticular Waxes ◽  
Pine Seedlings ◽  
Volatile Organic ◽  
Conifer Needles ◽  
Air Chemistry ◽  
Surface Waxes ◽  
Dynamic Exchange ◽  
Outdoor Location

Abstract. Biogenic volatile organic compounds (BVOCs) produced by plants have a major role in atmospheric chemistry. The different physicochemical properties of BVOCs affect their transport within and out of the plant as well as their reactions along the way. Some of these compounds may accumulate in or on the waxy surface layer of conifer needles and participate in chemical reactions on or near the foliage surface. The aim of this work was to determine whether terpenes, a key category of BVOCs produced by trees, can be found on the epicuticles of Scots pine (Pinus sylvestris L.) and, if so, how they compare with the terpenes found in shoot emissions of the same tree. We measured shoot-level emissions of pine seedlings at a remote outdoor location in central Finland and subsequently analysed the needle surface waxes for the same compounds. Both emissions and wax extracts were clearly dominated by monoterpenes, but the proportion of sesquiterpenes was higher in the wax extracts. There were also differences in the terpene spectra of the emissions and the wax extracts. The results, therefore, support the existence of BVOC associated to the epicuticular waxes. We briefly discuss the different pathways for terpenes to reach the needle surfaces and the implications for air chemistry.

scholarly journals A novel maize gene, glossy6 involved in epicuticular wax deposition and drought tolerance

2018 ◽  
Author(s):  
LI Li ◽  
Yicong Du ◽  
Cheng He ◽  
Charles R. Dietrich ◽  
Jiankun Li ◽  
...  
Keyword(s):  
Drought Tolerance ◽  
Intracellular Trafficking ◽  
Epicuticular Wax ◽  
Epicuticular Waxes ◽  
Wild Type ◽  
Terrestrial Plants ◽  
Surface Waxes ◽  
Extracellular Transport ◽  
Plant Surfaces ◽  
Wax Load

SUMMARYEpicuticular waxes, long-chain hydrocarbon compounds, form the outermost layer of plant surfaces in most terrestrial plants. The presence of epicuticular waxes protects plants from water loss and other environmental stresses. Cloning and characterization of genes involved in the regulation, biosynthesis, and extracellular transport of epicuticular waxes on to the surface of epidermal cells have revealed the molecular basis of epicuticular wax accumulation. However, intracellular trafficking of synthesized waxes to the plasma membrane for cellular secretion is poorly understood. Here, we characterized a maize glossy (gl6) mutant that exhibited decreased epicuticular wax load, increased cuticle permeability, and reduced seedling drought tolerance relative to wild type. We combined an RNA-sequencing based mapping approach (BSR-Seq) and chromosome walking to identify the gl6 candidate gene, which was confirmed via the analysis of multiple independent mutant alleles. The gl6 gene represents a novel maize glossy gene containing a conserved, but uncharacterized domain. Functional characterization suggests that the GL6 protein may be involved in the intracellular trafficking of epicuticular waxes, opening a door to elucidating the poorly understood process by which epicuticular wax is transported from its site of biosynthesis to the plasma membrane.SIGNIFICANCE STATEMENTPlant surface waxes provide an essential protective barrier for terrestrial plants. Understanding the composition and physiological functions of surface waxes, as well as the molecular basis underlying wax accumulation on plant surfaces provides opportunities for the genetic optimization of this protective layer. Genetic studies have identified genes involved in wax biosynthesis, extracellular transport, as well as spatial and temporal regulation of wax accumulation. In this study, a maize mutant, gl6 was characterized that exhibited reduced wax load on plant surfaces, increased water losses, and reduced seedling drought tolerance compared to wild type controls. The gl6 gene is a novel gene harboring a conserved domain with an unknown function. Quantification and microscopic observation of wax accumulation as well as subcellular localization of the GL6 protein provided evidence that gl6 may be involved in the intracellular trafficking of waxes, opening a door for studying this necessary yet poorly understood process for wax loading on plant surfaces.

scholarly journals Effect of epicuticular waxes from triticale on the feeding behaviour and mortality of the grain aphid, Sitobion avenae (Fabricius) (Hemiptera: Aphididae)

2016 ◽  
Vol 56 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Agnieszka Wójcicka
Keyword(s):  
Toxic Effect ◽  
Control Diet ◽  
Sitobion Avenae ◽  
Early Mortality ◽  
Epicuticular Waxes ◽  
Feeding Deterrence ◽  
Grain Aphid ◽  
Surface Wax ◽  
Choice Tests ◽  
Surface Waxes

AbstractSurface waxes from wax-covered triticale plants (RAH 122) were sprayed on plants of the waxless genotype RAH 366 or the surface waxes were used to make artificial diet preparations. The results were significant increases in the mortality of apterous adults of the grain aphid Sitobion avenae (Fabricius) (Hemiptera: Aphididae) at all concentrations tested in comparison with those aphids which fed on the control plants or aphids which were reared on the diets. In the choice tests, most aphids settled on plants without surface waxes or on diet preparations which did not have surface waxes (the controls). When the concentration of the surface waxes was increased on one of the plants or surface waxes were increased in the diet preparation, the number of wandering aphids increased. Those aphids which did not wander were mainly on the waxless control plants or on the waxless diet preparations. Aphids did settle on those plants or on the diet preparations which had 100 and 1,000 μg · g-1of surface wax. The aphids rarely settled on the diet preparations containing 10,000 μg ∙ g-1of surface waxes. From these observations it appears that surface waxes can act as a feeding deterrent. Since aphids on plants with surface waxes, or aphids which settled on diet preparations with surface waxes, started to die earlier than aphids fed only the control plants or the control diet preparations, it is possible that the surface waxes had a toxic effect that led to early mortality. Thus, it can be said that the surface waxes caused feeding deterrence and had a toxic effect on the aphids.

Gas Chromatography of Unsaponifiable Matter. III. Identification of Hydrocarbons, Aliphatic Alcohols, Tocopherols, Triterpenoid Alcohols, and Sterols Present in Olive Oils

1965 ◽  
Vol 48 (2) ◽  
pp. 417-433 ◽  
Author(s):  
Jerome Eisner ◽  
John L Iverson ◽  
Alfred K Mozingo ◽  
David Firestone
Keyword(s):  
Gas Chromatography ◽  
Unsaponifiable Matter ◽  
Homologous Series ◽  
Aliphatic Alcohols ◽  
The Third ◽  
Kernel Oil ◽  
Olive Oils ◽  
Olive Kernel ◽  
Branched Chain ◽  
Major Hydrocarbon

Abstract Olive oils, both foreign and domestic, were saponified, and the unsaponifiable matter was fractionated on a Florisil column. Gas chromatography of the first two hydrocarbon fractions confirmed that squalene was the major component of pressed and solvent-extracted pomace oils. However, iso-and/or anteiso- tctratriacontane was the major hydrocarbon in olive kernel oil. Hydrogenation and temperature programming indicated that there were several homologous series present, consisting of normal, iso-and/or anteiso-, and multiple branched chain hydrocarbons. Gas chromatography of the third Florisil fraction (tocopherols, high molecular weight aliphatic alcohols, and triterpenoid alcohol components) indicated the presence of three homologous series of normal, iso- and/or anteiso-, and multiple branched chain alcohols. The triterpenoid alcohols were used to distinguish between pressed and solvent-extracted pomace oils. As little as 5% of pomace oil could be detected in laboratory-prepared mixtures. Campesterol and beta-sitosterol were the two sterols present in olive oils. The Fitelson test detected olive oils consisting entirely or largely of pomace oils.

Composition of Epicuticular Waxes from Fruits of Jojoba (Simmondsia chinensis [Link] Schneider)

1982 ◽  
Vol 37 (11-12) ◽  
pp. 1053-1056 ◽  
Author(s):  
Paul-Gerhard Gülz
Keyword(s):  
Homologous Series ◽  
Cuticular Wax ◽  
Wax Esters ◽  
Hydrocarbon Fraction ◽  
Simmondsia Chinensis ◽  
Epicuticular Waxes ◽  
Cuticular Waxes ◽  
Branched Alkanes ◽  
Seed Coats ◽  
Long Chain

Abstract Epicuticular waxes were extracted with hexane from dry Jojoba pericarp and seed. These cuticular waxes consisted of hydrocarbons, wax esters, free acids, free alcohols and sterols; additionally aldehydes were found in the wax obtained from seed coats. The hydrocarbon fraction contained a homologous series of n-alkanes and branched alkanes but no alkenes. The composition of the wax esters of the cuticular wax was similar to that of the cotyledons. The esters are composed of monounsaturated long chain acids and alcohols.

Chemistry and Morphology of Epicuticular Waxes from Leaves of Five Euphorbia Species

1986 ◽  
Vol 41 (5-6) ◽  
pp. 521-525 ◽  
Author(s):  
Herbert Hemmers ◽  
Paul-Gerhard Gülz ◽  
Kurt Hängst
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Distribution Patterns ◽  
Epicuticular Waxes ◽  
Primary Alcohols ◽  
Chemical Methods ◽  
Morphological Appearance ◽  
Surface Waxes ◽  
Wax Crystals ◽  
Scanning Electron

The surface waxes of five Euphorbia species (Euphorbiaceae) were studied by chemical methods and by scanning electron microscopy. The yields of epicuticular waxes, expressed as percentages of the dry weights, differed from species to species. Qualitatively the five species showed the same wax composition but differences appeared in the amounts of single wax components and in their distribution patterns. The predominance of mainly saturated and long chained components as well as the high amounts of primary alcohols and triterpenols resulted in crystalline wax layers. The comparable chemical wax com position of all five species resulted in a quite similar morphological appearance of wax crystals.

Organ Specific Composition of Epicuticular Waxes of Cistus albidus L., Cistaceae

1988 ◽  
Vol 43 (11-12) ◽  
pp. 806-812 ◽  
Author(s):  
Sabine Hennig ◽  
Paul-Gerhard Gülz ◽  
Kurt Hängst
Keyword(s):  
Fatty Acids ◽  
Homologous Series ◽  
Wax Esters ◽  
Epicuticular Waxes ◽  
Unsaturated Lipids ◽  
Specific Composition ◽  
Cistus Albidus ◽  
Organ Specific ◽  
The Common ◽  
Chain Lengths

Abstract Epicuticular waxes from various organs of Cistus albidus L. showed always an organ specific composition. Leaf wax contained homologous series of very long chained and saturated wax components, such as hydrocarbons, wax esters, fatty acids and alcohols. Additionally in this wax extract triterpenoids and great amounts of resin were found. Sepal wax had nearly the same wax composition like that of leaves with a trend to shorter chain lengths and not so great amounts of resin. Petal wax contained the common wax lipids, too, but the homologous series showed a shift to shorter chain lengths, and great amounts of unsaturated lipids were found in hydrocarbons, wax esters and fatty acids. In addition triterpenol esters were found but no resin. Stamen wax was similar to that of petals. The shift to shorter chain lengths and the presence of great amounts of unsaturated lipids showed a characteristic distribution for stamens. Seed wax contained only saturated wax lipids. In contrast to leaf waxes, the short chain compounds were dominating, and triterpenoids and resin were missing. The chemical wax composition of the various organs of C. albidus was correlated to the surface structures of these organs by SEM pictures.

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