Epicuticular wax of Agropyron intermedium

Wax on leaves of Agropyron intermedium contains hydrocarbons (11%, C₂₇–C₃₃), esters (11%, C₃₂–C₆₀), free alcohols (180%, C₂₆) 25-oxohentriacontane-14,16-dione (17%), 10-oxohentriacontane-14,16-dione (5y%), 25-hydroxyhentriacontane-14,16-dione (12%) and 26-hydroxyhentriacontane-14,16-dione (2%). Wax on spikes contains additional components, C₂₅–C₃₃cis 9-alkenes (32% of hydrocarbons), and more β-diketones, 25-hydroxy (17%) and 26-hydroxy (3%) hentriacontane-14,16-diones, 10,25-dioxohentriacontane-14,16-dione (1%) and 4-hydroxy-25-oxo-(2%), 25-hydroxy-10-oxo-(1.3%) and 26-hydroxy-10-oxo-(0.7%) hentriacontane-14,16-diones; free alcohols were very minor components (1%, C₂₄–C₃₂).     

Epicuticular wax of Poa ampla leaves

Leaf wax of a glaucous variety of Poa ampla contains hydrocarbons (5%, C₂₃–C₃₅), esters (9%, C₃₆–C₅₆), free acids (3%, C₁₆–C₃₄), free alcohols (6%, mainly C₂₆); hentriacontane-14,16-dione (14%), 5-oxohentriacontane-14,16-dione (1%); hydroxy β-diketones (56%) and unidentified material (6%). The hydroxy β-diketones, which are more abundant in this wax than in others, were shown by ¹³C NMR to consist of 4-hydroxy (15%), 5-hydroxy (70%) and 6-hydroxy (15%) hentriacontane-14,16-diones.     

Epicuticular waxes of Secale cereale and Triticale hexaploide leaves

Wax on leaves of rye and of hexaploid Triticale (60–70-day-old plants) contains hydrocarbons (6–8%), esters (10%), free alcohols (14-8%), free acids (3%), hentriacontane-14,16-dione (39–45%), 25 (S)-hydroxyhentriacontane-14,16-dione (13–11%) and unidentified (14–15%). Diesters (1–3%) are also present in rye wax. Compositions of hydrocarbons (C₂₇-C₃₃) and esters (C₂₈,C₅₈) are similar for both waxes. Free and combined alcohols of rye wax are mainly hexacosanol but alcohols of Triticale wax are mainly octacosanol. The composition of Triticale wax is close to that of its wheat parent Triticum durum (cv. Stewart 63). Esters of wax from ripe rye contain 58% of trans 2,3-unsaturated esters. *NRCC No. 14033.     

Epicuticular waxes from Agropyron dasystachyum,agropyron riparium and Agropyron elongatum

Epicuticular waxes from whole plants of Agropyron dasystachyum var. psammophylum, A. riparium and A. elongatum contain hydrocarbons (5–8 %), long chain esters (12–15%) and free acids (2–5%). The major esters are C₃₄C₅₆ esters derived from C₁₆C₃₀ acids and alcohols (1-hexacosanol is the major alcohol) but C₃₁, C₃₃ and C₃₅ esters (3–11%) are also present. The latter esters are C₁₈ and C₂₀ acid esters of C₁₃ and C₁₅ 2-alkanols. A. dasystachyum wax contains 2% free alcohols, that of A. riparium contains 17% and that of A. elongatum 11% (1-hexacosanol is the major alcohol in each). Diesters (2%), C₈C₁₂ diols esterified by (E)-2-alkenoic acids, are present in A. riparium wax. Hentriacontane-14,16-dione is present: 29% in A. dasystachyum wax and 32% in A. riparium wax, but only 5% in A. elongatum wax. 25-Oxohentriacontane-14,16-dione forms 14% of A. dasystachyum wax and 27% of A. elongatum wax but the oxo β-diketones of A. riparium wax (5%) consist of both 10-oxo- and 25-oxohentriacontane-14,16-diones in the ratio 4:1. Hydroxy β-diketones of the waxes are 25- and 26-hydroxyhentriacontane-14,16-diones; in A. dasystachyum (20%) the ratio is 3:1, in A. elongatum (20%) the ratio is 9:1 but in A. riparium (5%) it is ca 1:2. The configuration of the hydroxyl group in the 26-hydroxy β-diketone is opposite to that in the 25-hydroxy derivative. The unusual composition of the oxygenated β-diketones of A. riparium confirms that this species should be regarded as separate from A. dasystachyum. Wax from A. elongatum also contains 4-hydroxy-25-oxohentriacontane-14,16-dione (4%) and an unusual oxo-β-ketol, 18-hydroxy-7,16-hentriacontanedione (2%), both these components are probably derived biosynthetically from the 25-oxo β-diketone which is the major component of this wax. Syntheses of racemic 18-hydroxy-7,16-hentriacontanedione and of a model β-ketol, 12-hydroxy-10-pentacosanone, are described.     

Leaf wax of Triticum aestivum

Leaf waxes from spring wheat varieties Selkirk and Manitou contain hydrocarbons (6%, 10%), long chain esters (14%, 13%), free acids (5%, 8%), free alcohols (19%, 21%), β-diketone (16%, 20%), hydroxy β-diketones (8%, 10%), unidentified gum (29%, 16.5%) and minor amounts of diol diesters, glycerides and aldehydes. The major hydrocarbon is nonacosane and major esters are octacosyl esters of C₁₄–C₃₂ acids but C₂₀ and C₂₂ alcohol esters of trans 2-docosenoic and tetracosenoic acids are also present (Selkirk 20%, Manitou 10% of total esters). Previously unknown trans 2-docosen-1-ol is present as an ester (Selkirk 5%, Manitou 2.5% of total esters). Free acids are C₁₄–C₃₂ acids and trans 2-docosenoic and tetracosenoic acids (Selkirk 30%, Manitou 9% of free acids). Octacosanol is the principal free alcohol. Hentriacontane-14,16-dione is the β-diketone and the hydroxy β-diketones are a 1:1 mixture of 8- and 9- hydroxyhentriacontane-14,16-diones.     

Epicuticular wax of Panicum virgatum

Leaf and stem wax of Panicum virgatum contains hydrocarbons (4%), esters (3%), free acids (2%), free alcohols (1%), triterpene alcohols (2%), β-diketones (69%) and hydroxy β-diketones (6%). Principal free alcohols range in chain length from C₂₆ to C₃₂. β-Diketones consist almost entirely of tritriacontane-12,14-dione and the hydroxy β-diketone consists only of 5(S)-5-hydroxytritriacontane-12,14-dione. The configuration of the hydroxyl group is the same as that of hydroxy β-diketones from festucoid grasses but opposite to that of the hydroxy β-diketone from Andropogon species.     

Changes in the composition of coffee leaf wax with development

Coffee leaf wax contains alkanes, free primary alcohols and free acids, together with unidentified substances. The relative amounts of each fraction varied with age: alkanes from 22–35% alcohols from 28-25%, and free acids from 22-14%. The major homologues of the alkane fraction were C₂₉ and C₃₁, of the alcohol fraction C₃₀ and C₃₂ and of the acid fraction C₂₈, C₃₀ and C₃₂. The ratio of both C₂₉:C₃₁ alkanes and C_3O:C₃₂ alcohols changed from 1:1 to 1:2 during development, although their combined sum in each case remained constant at 90% (for alkanes) and 73% (for alcohols) of the weight of the respective fractions.     

Fatty acids. Part 50. 13C nuclear magnetic resonance studies of olefinic fatty acids and esters

The ¹³C-NMR spectra of 48 cis alkenoic acids and esters (C₈–C₂₀), 18 trans alkenoic acids and esters (C₉–C₁₈), and 26 polyenoic acids and esters (C₁₈–C₂₂) are reported and interpreted. The characteristic features of such spectra which permit structural assignments to be made are discussed.     

Determination of structure and composition of suberin from the roots of carrot, parsnip, rutabaga, turnip, red beet, and sweet potato by combined gas-liquid chromatography and mass spectrometry

Suberin from the roots of carrots (Daucus carota), parsnip (Pastinaca sativa), rutabaga (Brassica napobrassica), turnip (Brassica rapa), red beet (Beta vulgaris), and sweet potato (Ipomoea batatas) was isolated by a combination of chemical and enzymatic techniques. Finely powdered suberin was depolymerized with 14% BF₃ in methanol, and soluble monomers (20-50% of suberin) were fractionated into phenolic (<10%) and aliphatic (13-35%) fractions. The aliphatic fractions consisted mainly of ω-hydroxyacids (29-43%), dicarboxylic acids (16-27%), fatty acids (4-18%), and fatty alcohols (3-6%). Each fraction was subjected to combined gas-liquid chromatography and mass spectrometry. Among the fatty acids very long chain acids (>C₂₀) were the dominant components in all six plants. In the alcohol fraction C₁₈, C₂₀, C₂₂, and C₂₄ saturated primary alcohols were the major components. C₁₆ and C₁₈ dicarboxylic acids were the major dicarboxylic acids of the suberin of all six plants and in all cases octadec-9-ene-1, 18-dioic acid was the major component except in rutabaga where hexadecane-1, 16-dioic acid was the major dicarboxylic acid. The composition of the ω-hydroxyacid fraction was quite similar to that of the dicarboxylic acids; 18-hydroxy-octadec-9-enoic acid was the major component in all plants except rutabaga, where equal quantities of 16-hydroxyhexadecanoic acid and 18-hydroxyoctadec-9-enoic acid (42% each) were found. Compounds which would be derived from 18-hydroxyoctadec-9-enoic acid and octadec-9-ene-1, 18-dioic acid by epoxidation, and epoxidation followed by hydration of the epoxide, were also detected in most of the suberin samples. The monomer composition of the six plants showed general similarities but quite clear taxonomic differences.     

Epicuticular waxes of four eragrostoid grasses

The major components of Sporobolus airoides wax were hydrocarbons (37%, C₂₇–C₃₃), those of Bouteloua curtipendula and Eragrostis trichoides waxes esters (28% and 31%, respectively) and those of Muhlenbergia wrightii wax free alcohols (57%, almost entirely C₂₈). Free alcohols formed 22% of the wax from B. curtipendula, 19 % of the wax from E. trichoides and 10% of the wax from S. airoides; the compositions ranged from C₂₆ to C₃₂ with C₃₂ the major component. These alcohol compositions are similar to those found for other species in the subfamily Eragrostoideae. The esters contain 32–46% of acylated triterpenols, principally α- and β-amyrins. Aldehydes were present in all the waxes except for that from S. airoides.     

Surface wax of Andreaea and Pogonatum species

The mosses Andreaea rupestris, Pogonatum aloides and P. urnigerum contain surface waxes in amounts of 0.05–0.12% dry wt. The waxes consisted of esters (C₃₈-C₅₄), primary alcohols (C₂₀-C₃₂), free fatty acids (C₁₆-C₃₀), and alkanes (C₂₁-C₃₁). Additionally, aldehydes (C₂₂-C₃₀) were major constituents in the wax of P. urnigerum. The classes and their chain length distributions in the surface waxes of these mosses are comparable to those of epicuticular waxes of higher plants.     

Epicuticular wax of Eragrostis curvula

Epicuticular wax of Eragrostis curvula contains hydrocarbons (6%), esters (13%), acids (3%), alkanols (4%), tritriacontane-12,14-dione (47%), 5(S)-5-hydroxytritriacontane-12,14-dione (14%) as major components. The esters consist of triterpenol esters (42%) as well as alkanol esters. The free alkanols consist principally Of C₁₆C₃₂ components, resembling those of waxes from panicoid, and some other eragrostoid, grasses. Minor components are triterpenols (0.7%), triterpenones (0.5%), triacylglycerols (0.3%), secondary alkanols (0.1%) and 5-oxotritriacontane-12,14-dione (0.1%).     

Low C18 to C20 fatty acid elongase activity and limited conversion of stearidonic acid, 18:4(n–3), to eicosapentaenoic acid, 20:5(n–3), in a cell line from the turbot, Scophthalmus maximus

The TF cell line, derived from a top predatory, carnivorous marine teleost, the turbot (Scophthalmus maximus), is known to have a limited conversion of C₁₈ to C₂₀ polyunsaturated fatty acids (PUFA). To illuminate the underlying processes, we studied the conversions of stearidonic acid, 18:4(n–3), and its elongation product, 20:4(n–3), in TF cells and also in a cell line, AS, derived from Atlantic salmon (Salmo salar), by adding unlabelled (25 μM), U-¹⁴C (1 μM) or deuterated (d5; 25 μM) fatty acids. Stearidonic acid, 18:4(n–3), was metabolised to 20:5(n–3) in both cells lines, but more so in AS than in TF cells. Δ5 desaturation was more active in TF cells than in AS cells, whereas C₁₈ to C₂₀ elongation was much reduced in TF as compared to AS cells. Only small amounts of docosahexaenoic acid (22:6(n–3)) were produced by both cell lines, although there was significant production of 22:5(n–3) in both cultures, especially when 20:4(n–3) was supplemented. We conclude that limited elongation of C₁₈ to C₂₀ fatty acids rather than limited fatty acyl Δ5 desaturation accounts for the limited rate of conversion of 18:3(n–3) to 20:5(n–3) in the turbot cell line, as compared to the Atlantic salmon cell line. The results can account for the known differences in conversions of C₁₈ to C₂₀ PUFA by the turbot and the Atlantic salmon in vivo.     

Wax composition of sargassum fulvellum

Sixty-seven compounds were characterized in the wax of Sargassum fulvellum. Characteristic components were the 5-methylhexyl esters of octanoic, decanoic, lauric, myristic, palmitic, palmitoleic, stearic, oleic, linoleic and linolenic, and the 2-ethylhexyl esters of the same acids. The wax of S. fulvellum contains hydrocarbons (1.6%), esters (21.8%), free acids (74.9%) and free alcohols (0.3%). The principal free alcohols range in chain length only from C₆ to C₇.     

Biosynthesis of the beta-diketones of barley spike epicuticular wax.

[1-¹⁴C]acetate and [2-¹⁴C]acetate were incorporated into the β-diketones of barley spike epicuticular wax via the peduncle. Utilizing column chromatography with dry copper acetate, the β-diketones were isolated and the labeling pattern in the hentriacontan-14, 16-dione determined after its degradation. A modified iodoform procedure was used to give myristic and palmitic acids. Radio-gas chromatography was then performed on the products of chemical α-oxidation of the separated fatty acids. This procedure, in effect, gave the specific activity of every carbon atom of hentriacontan-14,16-dione except carbon-1 to carbon-5 (from myristic acid) and carbon-27 to carbon-31 (from palmitic acid) for each labeled substrate. The specific activity of carbon-15 was determined by an indirect method. On the basis of these data it is suggested that the hentriacontan-14,16-dione is synthesized from the carbon-31 end of the molecule by elongation as follows. C₂ units are added, perhaps to a mixture of short chain precursors, to give a chain with 12 carbon atoms. This chain is then elongated to one with 16 carbon atoms so that the four added carbon atoms are uniformly labeled. Following this, the chain with 16 carbon atoms is elongated with C₂ units to give the complete molecule. Possibly some change in mechanism occurs in this last elongation process when the chain is 22 carbon atoms long. Barley spike wax β-diketones contain about 2% nonacosan-13, 15-dione which seems to be synthesized in an analogous manner.     

Surface lipids of Sphaerotheca fuliginea spores

The major components (50%) of the surface lipid extract of fungal spores (5.6% of dry spore wt) of Sphaerotheca fuliginea are esters of primary alcohols and fatty acids. Esters (15%) of primary alcohols and a Δ^2t acid are present. The major acid moieties of the alkyl esters are C₂₂ and C₂₄ and of the Δ^2t alkyl ester is Δ^2t C₂₂; for both classes eicosanol is the major primary alcohol. The major ester of each class was concluded to be eicosanyl docosanoate and eicosanyl trans-2-docosenoate. Minor components are saturated and Δ^2t methyl and diol diesters and free fatty acids. The major acid moieties of the diol diesters are C₂₂ and C₂₄ and the major diol is 1,12-dodecanediol.     

Homologous long-chain δ-lactones in leaf cuticular waxes of Cerinthe minor

A homologous series of eleven δ-lactones (1,5-alkanolides) was identified in cuticular waxes from leaves of Cerinthe minor L., six of them representing novel compounds. They accounted for 79% of the total coverage of 41 μg wax per cm² leaf area. Various chemical transformations with product identification by GC-mass spectrometry and GC-FTIR were employed to assign the structures. The chain-lengths of the δ-lactones ranged from C₂₂ to C₃₂ and even-numbered homologues were prevalent. Additionally, aldehydes (C₂₆–C₃₀), alkanes (C₂₃–C₂₉), primary alcohols (C₂₆–C₃₂), alkanoic acids (C₂₀–C₃₂), wax esters (C₄₀–C₅₆) and lupeol were detected.     

Specific inhibition of alkane synthesis with accumulation of very long chain compounds by dithioerythritol, dithiothreitol, and mercaptoethanol in Pisum sativum

Sodium [1-¹⁴C]acetate and [1-¹⁴C]stearic acid were readily incorporated into hydrocarbons, secondary alcohols, wax esters, aldehydes, primary alcohols, and fatty acids in young pea leaves (Pisum sativum). Dithioerythritol, dithiothreitol, and mercaptoethanol (but not glutathione and cysteine) severely inhibited the incorporation of labeled acetate into alkanes and secondary alcohols with accumulation of label in wax ester and aldehyde fractions. Detailed radio gas-chromatographic analyses of the fatty acids of both the surface lipid components and internal lipids showed that dithioerythritol and mercaptoethanol specifically inhibited n-hentriacontane (C₃₁) synthesis and caused accumulation of C₃₂ aldehyde, suggesting that the inhibition was at or near the terminal step in alkane biosynthesis, presumably decarboxylation. Trichloroacetate, at a concentration that inhibited C₃₁ alkane synthesis but not the synthesis of alcohols (C₂₆ and C₂₈) specifically inhibited the formation of C₃₂ aldehyde but not that of the C₂₆ or C₂₈ aldehyde. From these results, it is concluded that the C₃₂ aldehyde is derived from the C₃₂ acyl derivative which is the precursor of C₃₁ alkane.     

<Emphasis Type="Italic">Roseomonas aeriglobus</Emphasis> sp. nov., isolated from an air-conditioning system

A novel pale pink-coloured, strictly aerobic, Gram-stain negative bacterial strain, designated strain KER25-12^T, was isolated from a laboratory air-conditioning system in South Korea. Cells were observed to be non-motile cocci showing positive catalase and oxidase reactions. Strain KER25-12^T was found to grow at 10–30 °C (optimum, 25–30 °C), at pH 4.0–9.0 (optimum, pH 6.0–7.0) and in the presence of 0–2% (w/v) NaCl (optimum, 0%). Ubiquinone-10 and spermidine were detected as the sole respiratory quinone and the predominant polyamine, respectively. The major fatty acids were identified as summed feature 8 (comprising C_18:1 ω7c and/or C_18:1 ω6c), summed feature 3 (comprising C_16:1 ω7c and/or C_16:1 ω6c), C_16:0 and C_18:0. The genomic DNA G+C content of strain KER25-12^T was determined to be 70.0 mol%. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain KER25-12^T belongs to the genus Roseomonas and shows high sequence similarity to Roseomonas aerilata 5420S-30^T (98.57%), Roseomonas pecuniae N75^T (97.44%) and Roseomonas vinacea CPCC 100056^T (97.40%). Based on the morphological, physiological, chemotaxonomic and phylogenetic features, strain KER25-12^T is concluded to represent a novel species of the genus Roseomonas, for which the name Roseomonas aeriglobus sp. nov. is proposed. The type strain is KER25-12^T (= KACC 19282^T = JCM 32049^T).     

Bile salts of vertebrates: structural variation and possible evolutionary significance

Biliary bile salt composition of 677 vertebrate species (103 fish, 130 reptiles, 271 birds, 173 mammals) was determined. Bile salts were of three types: C₂₇ bile alcohols, C₂₇ bile acids, or C₂₄ bile acids, with default hydroxylation at C-3 and C-7. C₂₇ bile alcohols dominated in early evolving fish and amphibians; C₂₇ bile acids, in reptiles and early evolving birds. C₂₄ bile acids were present in all vertebrate classes, often with C₂₇ alcohols or with C₂₇ acids, indicating two evolutionary pathways from C₂₇ bile alcohols to C₂₄ bile acids: a) a ‘direct’ pathway and b) an ‘indirect’ pathway with C₂₇ bile acids as intermediates. Hydroxylation at C-12 occurred in all orders and at C-16 in snakes and birds. Minor hydroxylation sites were C-1, C-2, C-5, C-6, and C-15. Side chain hydroxylation in C₂₇ bile salts occurred at C-22, C-24, C-25, and C-26, and in C₂₄ bile acids, at C-23 (snakes, birds, and pinnipeds). Unexpected was the presence of C₂₇ bile alcohols in four early evolving mammals. Bile salt composition showed significant variation between orders but not between families, genera, or species. Bile salt composition is a biochemical trait providing clues to evolutionary relationships, complementing anatomical and genetic analyses.