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Analytical pyrolysis and FTIR spectroscopy of fossil Sequoiadendron giganteum (Lindl.) wood and MWLs isolated hereof

Recent and fossil woods from the genus of Sequoiadendron, as well as their milled wood lignins were investigated by means of FTIR spectroscopy and pyrolysis GC/MS technique. Though almost same in appearance the differences in band intensities of FTIR-spectra reveals the distinctly increased aromatic character and the oxidation in fossil specimens. More detailed information about the changes in old wood were obtained by analytical pyrolysis, which delivers degradation products with shortened side chains and more saturated units relating to fossil lignin.ZusammenfassungRecentes und fossiles Holz der Gattung Seqoiadendron giganteum, sowie daraus isoliertes Björkman-Lignin wurden mittels FTIR Spektroskopie und GC/MS Pyrolyse-Technik untersucht. Obwohl sich die Holzarten äußerlich sehr ähneln, zeigen die Unterschiede der Bandenintensität in den FTIR Spektren einen deutlich erhöhten, aromatischen Charakter und Oxidationsgrad in den fossilen Proben. Detailliertere Information über Veränderungen in den alten Holzarten wurden durch pyrolytische Analyse gewonnen, welche Abbauprodukte mit kürzeren Seitenketten und gesättigtere Einheiten des fossilen Lignin aufweisen.

The composition of volatile extractives from the wood of Juniperus excelsa, Juniperus foetidissima and Juniperus oxycedrus

J. excelsa, J. foetidissima and J. oxycedrus. Among the compounds the monoterpenes exist in minor amounts while the sesquiterpenes including their oxygenated members as well as sesquiterpene alcohols consist of the majority of the whole substances. The existence of some compounds of the oils might be attributes of the species and their sap- and heartwood. On the other side though notable differences, the essential oils of Turkish juniper woods resemble the commercial cedar wood oils.J. excelsa, J. foetidissima und J. oxycedrus. Monoterpene bilden einen geringen Anteil der Extraktstoffe. Der Hauptteil besteht aus Sesquiterpenen mit deren Oxydationsprodukten. Das Vorkommen einiger der Öle könnte charakteristisch sein für die jeweilige Art bzw. deren Splint- und Kernholz Allerdings gleichen diese Öle, trotz geringer Unterschiede, den wesentlichen Ölbestandteilen von Kommerziellen Zedernhölzern.

Pretreatment of poplar by acid and alkali for enzymatic hydrolysis

SummaryThe dilute acid pretreatment in a plug flow reactor and alkali pretreatments with caustic solutions at different conditions followed by enzymatic hydrolysis resulted in drastically improved glucose yields for aspen and hybrid poplar. The acid pretreatment conditions must be carefully chosen to open the cellulosic structure allowing rapid diffusion of enzyme. The effectiveness of pretreatment is chiefly based on the enlargement of the pore size suitable for enzyme molecules.

Composition of Volatile Foliage Isolates from Cupressus sempervirens Varieties (Var. horizontal Mill. and pyramidalis Nyman) Growing in Turkey

Abstract In order to differentiate two varieties of Cupressus sempervirens, volatile foliage isolates obtained from 12 trees of variety horizontalis and 12 trees of var. pyramidalis were analyzed by GC and GC/MS. About 86–87% of total peak areas of chromatograms consist of monoterpenes and evaluating their composition in qualitative and quantitative manner they do not show significant differences with regard to varieties. Some increments of terpinen-4-ol, α—terpineol and α—terpinyl acetate was recognizable in the variety horizontalis, while the variety pyramidalis contained germacrene D and abietadiene to somewhat higher level. On the other side, a higher percentage of α—fenchene than that of camphene and the presence of a monoterpene hydrocarbon sylvestrene were found to bear some chemotaxonomic value for the taxon C. sempervirens.

Fungal growth inhibition by wood extracts from Juniperus foetidissima and J. oxycedrus

SubjectSap- and heartwood extracts obtained by successive extractions with cyclohexane, chloroform, ethanol and hot water from J. foetidissima and J. oxycedrus were tested for their antifungal activity by using the agar plate method. Generally, the extractive substances of heartwoods soluble in nonpolar or slightly polar solvents show higher activities, whereas the extract fractions with higher polarity also seem to possess notable inhibition in case of sapwoods.

Characterization of methanol extracts from Quercus hartwissiana wood and bark

The MeOH extracts of wood and bark from Quercus hartwissiana have been investigated by GC-MS after derivatization, as well as by classical spectroscopic methods. The results for the free compounds revealed that ellagic acid, catechin, gallic acid, quercitol, and also long chain fatty acids, sugars, and sitosterol were the essential compounds in wood and bark, most of them being present in differing amounts. Quercitol, a characteristic compound for the oak wood tannin, was also recognized and determined in oak bark extracts in this study. Amounting to 1/4th to 1/3rd of the free compounds, the bark had the highest catechin content. While the content of sugars, such as fructose and glucose, increased in sapwood and bark extracts remarkably, the amounts of these compounds decreased in extracts of heartwood. The profile of the bound compounds contained sugars (i.e., arabinose, xylose, and, above all, glucose), ellagic and gallic acids, quercitols, and inositols. Compared with the composition of free compounds, the hydrolyzed extracts showed relatively higher amounts of sugars, especially glucose, gallic acid and quercitol.

Cyclohexane extracts of black pine wood naturally grown in eastern Thrace

Pinus nigra var. pallasiana, naturally grown in eastern Thrace, were analyzed by means of GC-MS with regard to tree growth rate and chemotaxonomic purposes. High amounts of sterols but less resin acid content are distinctive for slow growing wood. Compared to extractives of Anatolian black pine, Thracian wood yields greater amounts of resin acids but somewhat less sterols suggesting that it can rather be considered as an ecotype. Pinifolic acid, manoyl oxide and cembrene were detected in Thracian specimens, but their existence in Anatolia black Pine is unknown.Pinus nigra var. pallasiana, die natürlich in Ost-Trazien vorkommt, wurden mittels GC-MS analysiert im Hinblick auf Unterschiede in der Wachstumsgeschwindigkeit der Bäume bzw. für chemotaxonomische Zwecke. Hohe Sterolanteile aber geringere Mengen an Harzsäuren erwiesen sich als charakteristische Unterscheidungsmerkmale für langsam wachsendes Holz. Im Vergleich zu Extraktstoffen der Schwarzkiefer aus Anatolien enthalten die thrakischen Hölzer mehr Harzsäuren, jedoch etwas geringere Sterolanteile; es handelt sich daher wahrscheinlich eher um eine ökologische Unterart. Pinifolsäure, Manoyloxid und Cembren wurden in den thrakischen Proben gefunden; dagegen ist deren Vorkommen in der anatolischen Schwarzkiefer nicht bekannt.

The Estimation of Acidic Behavior of Wood by Treatment with Aqueous Na(2)HPO(4) Solution.

As a new approach, the acidity that wood exhibits under moderate conditions is assayed by stimulated dissociation of weak wood acids in lightly basic secondary phosphate solutions. To assure a sufficient dissociation of hardly soluble weak acids in the solution, the amount of wood suspended in Na2HPO4 solutions should be small but vary depending on the degree of acidity of wood species. However, the difficulties are associated with the titration of very dilute acids limiting the precision of the measurement. If the disintegrated wood is suspended in a secondary phosphate solution, the weak woods acids form the conjugate acid Na2HPO4 from secondary phosphate Na2HPO4 resulting in a pH fall of the solution. The decrease in the pH value in phosphate solution, which depends on the wood acidity, can be evaluated to estimate the acidity arising from wood under moderate conditions.

Chemical Characterization of Volatile Needle Oils from Anatolian Fir Species: Abies nordmanniana (Stev.) Mattf., A. bornmülleriana Mattf., A. equitrojani Aschers et Sint. and A. cilicica Carr.

Abstract Abies nordmanniana, A. bornmülleriana, A. equi-trojani and A. cilicica, four native fir species in Turkey, were characterized by means of GC/MS and GC-FID analyses of their needle essential oils. Large amounts of δ-3 carene, present in needles of A. nordmanniana and A. cilicica subsp. cilicica differentiated these species, since this compound is not found in the needles of other Anatolian firs and in those of European counterparts. The percentages of santene and germacrene-D as well as the ratio of percentage of β-pinene to percentage of myrcene can be used to distinguish carene-containing Turkish firs from each other. Remaining West Anatolian fir species (A. bornmülleriana, A. equi-trojani and A. cilicica subsp. isaurica) were found to have essential oils of the same qualitative composition. By cluster analysis using SPSS software, the Anatolian firs were divided practically into two groups, characterized by either existence or absence of δ-3 carene in needle extracts.

Composition of Essential Oils from Fir (Abies) Wood Species Grown in Turkey

Abies species naturally grown in Turkey are represented by four species and two subspecies. Abies equi-trojani (Aschers & Sint.) and Abies bornmulleriana (Mattf.) occur in western and northwestern regions. Abies cilicica subsp. isaurica (Coode & Cullen) and Abies cilicica subsp. cilicica (Antoine & Kotschy) Carr. are widespread in the southern part of the country (on Taurus mountains), and Abies nordmanniana (Steven) Spach is native in the eastern Black Sea region of Anatolia [1]. The main cell wall constituents (lignin, polysaccharides) of the woods from these species were studied by Ozdemir [2]. However, there have been no reports on the constituents of wood essential oils of Anatolian Abies species. On the other hand, Abies woods characteristically contain juvabiones, which are insect juvenile hormone related compounds. As a group of sesquiterpenoids, juvabiones and dehydrojuvabiones have been investigated in some fir woods [3–9]. In the present study, the components of the essential oils isolated from the woods of Anatolian fir species by hydrodistillation were analyzed and compared with one another. Two representative trees from each of a total of ten regions were felled to collect wood samples; A. bornmulleriana: Bolu and Uludag; A. equi-trojani: Kalkim and Gurgen; A. cilicica subsp. cilicica: Andirin and Goksun; A. cilicica subsp. isaurica: Bucak and Akseki; A. nordmanniana: Artvin and Torul. The essential oil yields of Anatolian fir woods were remarkably low, in the range 0.01–0.02%. GC-MS results of the essential oils from fir woods are shown in Table 1. Generally, fir essential oils exhibited large differences in both the composition and percentages of compounds between species and from tree to tree. Even within the same region and species, the essential oil composition could vary greatly. Therefore, in this study the composition of fir wood essential oils is given in the compound classes with special emphasize on juvabiones. As can be seen from Table 1, sesquiterpenes are present in the highest percentages in many fir woods. In particular, juvabiones and nerolidol were the main compounds among the sesquiterpenes, and these compounds together with fatty acids constitute a high percentage in some fir species. The monoterpenes often occur in small quantities, and some diterpene related compounds in trace amounts were recorded in fir woods. The monoterpenes varied widely both in their content and chemical structures. It is well known that juvabiones are characteristic compounds for Abies species. As expected, juvabione, dehydrojuvabione, and dihydrojuvabione were detected also in the essential oils of Anatolian fir woods. Both juvabione and dehydrojuvabione concentrations had large variations among the tested trees. This finding is in good agreement with the literature showing that the juvabiones in fir woods can vary considerably in a qualitative and quantitative manner among trees within the same species [3–6, 10]. In our case, juvabione was present in larger amounts than dehydrojuvabione in all 20 trees. This finding is contradictory to the data of [11] who reported that the extract of A. fraseri had a higher amount of dehydrojuvabione than juvabione. It is of interest to note that the Table 1 shows larger variations in juvabione, dihydrojuvabione, and dehydrojuvabione concentrations in fir woods. Similar results were reported for A. balsamea [3], A. alba [4], A. lasiocarpa [5], A. sachalinensis [6], and A. bifolia [10]. These authors studied the juvabiones isolated from hexane or petroleum ether extracts of fir woods and elucidated the structure of these compounds by different techniques. However, in our study the juvabiones were isolated from the oily layer of the water distillates obtained by hydrodistillation. The juvabione content of Abies fraseri woods under intact and infested condition attacked by balsam woody adelgid was studied. The results showed that infested firs had higher mean juvabione levels than uninfested trees [11].