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1.
We investigated norlignan coloration with alkaline treatment to clarify the relationship between the blackening of sugi (Cryptomeria japonica D. Don) heartwood and norlignans in the heartwood. Of the four main norlignans (agatharesinol, sequirin-C, sugiresinol, hydroxysugiresinol)
of sugi heartwood, only sequirin-C was clearly colored with alkaline treatment (0.4% potassium hydrogencarbonate solution,
pH 8.6). Sequirin-C changed color to deep purple with alkaline treatment. The absorbance spectrum of colored sequirin-C had
two peaks (450 and 525nm) and one shoulder (626nm). Coloration began at pH 6.2.). The spectrum of blackened sugi heartwood
was similar to that of sequirin-C treated with alkali. A catechol nucleus and a double bond conjugated with a benzene nucleus
play important roles in norlignan coloration with alkaline treatment. The number of hydroxyl groups is related to solubility
in alkaline solution, and, therefore, whether a norlignan changes color also depends on the number of hydroxyl groups. Based
on these results, we concluded that sugi heartwood turns black because sequirin-C, which is readily soluble in alkaline solution
and can form a large intramolecular conjugation system when alkalized, is converted to products with a deep purple color as
the heartwood is basified. 相似文献
2.
3.
The reactivity of previously prepared antiserum against agatharesinol, a norlignan, was determined by competitive inhibition–ELISA (enzyme-linked immunosorbent assay) using several natural compounds that are representative of plant extractives as competitive inhibitors. The antiserum strongly reacted with some norlignans (i.e., agatharesinol, hinokiresinol, and metasequirin C), each of which has a common chemical-structural unit. This result suggests that the antiserum recognizes the specific chemical-structural unit composing those norlignans. Moreover, differences in the reactivities of the antiserum with agatharesinol derivatives and synthetic chalcones propose the trans-3-p-hydroxyphenyl-1-phenylpropene structural unit as the major antigenic determinant for the antiserum.Part of this paper was presented at the 45th Lignin Symposium, Matsuyama, October 2000 and the 51th Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 相似文献
4.
To establish an experimental approach for studying the biosynthetic pathway of agatharesinol, a norlignan, induction of the
formation of agatharesinol in Cryptomeria japonica (Japanese cedar, sugi) was attempted. Wood sticks were prepared from the sapwood immediately after cutting a sugi tree down,
and they were allowed to stand in desiccators in which the humidity was adjusted to 76% and 88%, and in a room. When the wood
sticks were allowed to stand in 76% humidity and in a room, they dried rapidly and no formation of agatharesinol was demonstrated
by gas chromatography-mass spectrometry. These results suggest that in the sapwood dried rapidly, the cells that were biologically
active in the sapwood, probably ray parenchyma cells, die rapidly and completely before the biosyntheses of secondary metabolites
including agatharesinol was wholly established. The wood sticks allowed to stand in 88% humidity, on the other hand, dried
gradually compared with the sticks placed in 76% humidity and in a room, and agatharesinol was formed as one of the predominant
ethyl acetate extractives. These results suggest that delaying the drying of the sapwood sticks can control the dying period
to an appropriate length for the ray parenchyma cells, during which the biosynthesis of agatharesinol is induced.
Part of this study was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004 相似文献
5.
Lignans and norlignans constitute abundant classes of phenylpropanoids. Biosynthesis of these compounds has received widespread
interest, mainly because they have various clinically important biological activities. In addition, lignans and norlignans
are often biosynthesized and deposited in significant amounts in the heartwood region of trees as a metabolic event of heartwood
formation, probably preventing heart rot by heart-rot fungi. Furthermore, biosynthetic reactions of lignans and norlignans
involve unique stereochemical properties that are of great interest in terms of bioorganic chemistry and are expected to provide
a model for biomimetic chemistry and its application. We outline the recent advances in the study of lignan and norlignan
biosynthesis. 相似文献
6.
Heartwood affects the utility of wood because it differs in some properties compared to sapwood. To regulate heartwood formation,
its mechanism must be elucidated. However, the molecular basis underlying heartwood formation remains largely unknown. To
obtain clues to understand the mechanism at a molecular level, we collected expressed sequence tags (ESTs) from the transition
zone (TZ) of Cryptomeria japonica D. Don in November, in which heartwood formation is considered to proceed. A total of 1029 ESTs were assembled into 744 unique
sequences (103 clusters and 641 singletons). Putative functions were assigned to 291 nuclear-encoded sequences, and they were
grouped into 21 categories according to the eukaryotic orthologous groups functional classification. We selected 20 genes
for enzymes or proteins, then examined their expression patterns among different organs. The expression levels of nine genes
were higher in November than in June in the TZ. The genes encode two enzymes in glycolysis, invertase, methionine adenosyltransferase,
glutathione transferase, the lipid transfer protein, Bet v 1 allergen, the dehydrin and the function-unknown protein. This
study has provided the first large-scale EST information from the TZ of conifers, which will be useful for understanding the
physiological processes in the TZ at a molecular level. 相似文献
7.
Kazuya Tsuruta Yayoi Yoshida Norihisa Kusumoto Nobuhiro Sekine Tatsuya Ashitani Koetsu Takahashi 《Journal of Wood Science》2011,57(6):520-525
The growth inhibition activities of essential oils obtained from Cryptomeria japonica, Chamaecyparis obtusa, and Pinus thunbergii were examined against the bacillariophyceae Skeletonema costatum, also known as red tide plankton. The essential oils were extracted from the heartwood, leaves, and bark of these typical
indigenous Japanese conifers. The essential oils from C. japonica bark and P. thunbergii heartwood possessed strong growth inhibition activity. The chemical compositions of these essential oils were analyzed by
gas chromatography/flame ionization detection (GC-FID) and gas chromatography/mass spectrometry (GC-MS). α-Terpineol and longifolene were the main components of the essential oil from P. thunbergii heartwood. The C. japonica bark essential oil was mainly composed of α-terpineol, δ-cadinene, isophyllocladene, and ferruginol. Ferruginol and longifolene showed more potent growth inhibition against S. costatum than hinokitiol (β-thujaplicine), which is known to be a strong antifungal compound among wood components. Ferruginol and longifolene were important
factors for the growth inhibition activity of the essential oils from C. japonica bark and P. thunbergii heartwood, respectively. These results suggest the possibility of using C. japonica bark and P. thunbergii heartwood for the control of red tide plankton. 相似文献
8.
There are indications that the drying process may have negative effects on the natural durability of wood. The impact of various
drying processes on the durability of Scots pine lumber has been evaluated with mass loss in a decay test with brown rot fungus,
Coniophora puteana, as measure of the decay resistance of sapwood and inner and outer heartwood. Drying with or without steam conditioning was
performed in six different series: air drying, kiln drying at temperature ranges commonly used in Swedish sawmills at 70°C
and 90°C with two different regulation principles, and one high-temperature drying at 110°C. Durability varied considerably
both between and within boards. Sapwood showed considerable less durability than heartwood. No difference in durability was
found between inner heartwood and outer heartwood. Air-dried heartwood showed the highest durability compared to other drying
series. The lowest durability in sapwood and heartwood was found for series dried at the 90°C temperature level with high
material temperature early in drying. The interpretation is that the duration of high material temperature at high moisture
content (MC) is the critical combination for decay resistance in heartwood. Steam conditioning after drying decreased durability
in sapwood. 相似文献
9.
Dr. J. B. Boutelje 《Wood Science and Technology》1990,24(2):191-200
Summary Nitrogen contents have been determined at different depths from the surface of dried pine (Pinus sylvestris) and spruce (Picea abies) lumber. The effects of factors such as time of felling, storage of the timber, and drying process for the lumber, have been studied. Part of the selected lumber was characterized by surfaces which were yellowish after drying. At such surfaces, to a depth of about 2 mm, a high accumulation of nitrogen was always found. Yellowing is enhanced in lumber from wet-stored timber but also occurs in other lumber. Some possible contributive factors are suggested. More research in this field is proposed. The nitrogen gradients in outer sapwood without a yellow surface and in inner sapwood and in heartwood were much weaker. The effect which enrichment of nitrogenous compounds at surfaces may have on timber with regard to its disposition towards moulding is discussed. Although attention is drawn to the fact that strong nutrient gradients may occur, it must be emphasised that in most lumber nutrient gradients are weak and probably without practical consequence for its susceptibility towards fungal attack. 相似文献
10.
Junji Matsumura Yoko Yamasaki Kazuyuki Oda Yoshitake Fujisawa 《Journal of Wood Science》2005,51(4):328-333
Nine trees of Cryptomeria japonica from six elite tree clones with a broad range of heartwood colors were selected. The profiles of pit aspiration percentage (ASP) of earlywood and latewood from pith to bark for green and air-dry conditions were determined to study the relationship between heartwood color and pit aspiration. Confocal laser scanning microscopy (CLSM) observations showed that the ASP of earlywood was low in sapwood and high in heartwood in the green condition. Pit aspiration increased in intermediate wood when compared with sapwood. On the other hand, latewood pits did not aspirate during heartwood formation. Comparing the air-dry condition with the green condition, sapwood pits aspirated during drying in both earlywood and latewood; however, there was no significant difference in pit aspiration of heartwood. There was no significant difference between samples with red and black heartwoods for ASP. The difference in ASP between individual trees was larger than that by heartwood color. The general advantage of CLSM over light microscopy is that serial optical sections along the Z axis can be obtained for any moisture condition, without the need for thin sectioning or embedding. 相似文献
11.
Nobumasa Bito Ryogo Nakada Eitaro Fukatsu Yasuyuki Matsushita Kazuhiko Fukushima Takanori Imai 《Annals of Forest Science》2011,68(6):1049-1056
• Introduction
In Cryptomeria japonica, heartwood properties are considered to be affected by specific extractives. It remains unclear whether traits of specific heartwood compounds are under genetic control. 相似文献12.
Binderless particleboards were manufactured from sugi (Cryptomeria japonica D. Don) heartwood and sapwood by hot-pressing (pressure: 5 MPa; temperatures: 180°, 200°, and 220°C; times: 10, 20, and 30
min), and the board properties [internal bonding (IB), thickness swelling (TS), water absorption (WA)] were investigated to
evaluate the self-bonding ability. The IB, TS, and WA of the boards from sugi heartwood were better than those of the boards
from sugi sapwood at any hot-pressing condition. Therefore, it was suggested that the self-bonding ability of sugi heartwood
was superior to that of sugi sapwood. Then, sugi heartwood and sapwood powder with grain size 10 βm were used as a binder
for plywoods. Four kinds of plywood were manufactured from the combination of powder and veneer, both of which were prepared
from sugi heartwood and sapwood under the same hot-pressing conditions as the binderless particleboard, and the adhesive shear
strength and wood failure of the plywood were investigated. As a result, the plywood composed of sugi heartwood veneer met
the second grade of JAS for plywood, when either powder was used as a binder, when they were pressed at 200°C for 20–30 min
and 220°C for 10 min. 相似文献
13.
The purpose of this study was to compare the distribution of moisture contents (MCs) along the radial direction during radio-frequency/vacuum (RF/V) drying of log cross sections of heartwood (HLC) where sapwood was removed from a green log cross section and log cross section of mixed sapwood and heartwood (MLC) prepared with debarked logs of Japanese larch (Larix leptolepis) and locust (Robinia pseudoacacia). For Japanese larch, an even distribution of MC was observed over the entire cross section in HLC not only at the initial stage of drying but also up to the completion of drying. Furthermore, the moisture gradient between the outermost slice and the adjacent inner slice was more gradual compared with that in MLC. For locust, the moisture gradient between the outermost slice and the adjacent inner slice became severe as drying progressed. It decreased after reaching the maximum during the middle stage of drying but continued until the late stage of drying. Furthermore, despite the fact that the average initial MC of mixed slice within MLC was higher compared with that in heartwood slice, this trend reversed immediately after drying started. It was suggested that the possibility of formation of border checking would be high during drying the MLC, since it would be so complicate that the sapwood and heartwood reach fiber saturation point together because of differences in their green MCs and permeability between them. 相似文献
14.
Shin-ichiro Tohmura Atsuko Ishikawa Kohta Miyamoto Akio Inoue 《Journal of Wood Science》2012,58(1):57-63
A mechanism of acetaldehyde emission from wood induced by the addition of ethanol was proposed. It is known that acetaldehyde
generation is due to the oxidation of ethanol via a metabolic process involving alcohol dehydrogenase (ADH) in living bodies.
However, it remains unclear whether the enzymatic alcohol oxidation is applicable to wood. We investigated possible factors
of wood parts, conditioning, storage sites, and heating and sterilization treatments on acetaldehyde emission using the syringe
method and HPLC analysis. We reconfirmed that acetaldehyde emission was observed only when ethanol was added to wood. Greater
acetaldehyde emissions were obtained in heartwood compared to sapwood in both Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.) specimens. In addition, an acetaldehyde conversion rate of 1–2 mol% was determined in green cedar heartwood samples,
while, conversely, air-dried cedar heartwood samples showed 4–5 mol%. Ethylene oxide gas sterilization had the effect of decreasing
acetaldehyde emission on air-dried wood, but not on green wood. Autoclave sterilization could completely prevent acetaldehyde
emissions from both green and air-dried wood. These results suggested that an original ADH in wood and an attached ADH from
the outside via microorganisms onto wood were assumed to be the primary causes of acetaldehyde emissions from wood induced
by the addition of ethanol. 相似文献
15.
In this study heartwood from a Chinese fir [Cunninghamia lanceolata (Lamb.) Hook] plantation was treated using a high-temperature drying (HTD) method at 115°C, a low-temperature drying (LTD)
method at 65°C, and freeze vacuum drying (FVD), respectively. The dynamic viscoelastic properties of dried wood specimens
were investigated. The measurements were carried out at a temperature range of −120 to 250°C at four different frequencies
(1, 2, 5, and 10 Hz) using dynamic mechanical analysis (DMA). We have drawn the following conclusions: 1) the storage modulus
E′ and loss modulus E″ are the highest for HTD wood and the lowest for FVD wood; 2) three relaxation processes were detected in HTD and LTD wood,
attributed to the micro-Brownian motion of cell wall polymers in the non-crystalline region, the oscillations of the torso
of cell wall polymers, and the motions of the methyl groups of cell wall polymers in the non-crystalline region in a decreasing
order of temperatures at which they occurred; and 3) in FVD wood, four relaxation processes were observed. A newly added relaxation
is attributed to the micro-Brownian motions of lignin molecules. This study suggests that both the HTD and the LTD methods
restrict the micro-Brownian motion of lignin molecules somewhat by the cross-linking of chains due to their heating history.
__________
Translated from Journal of Beijing Forestry University, 2008, 30(3): 96–100 [译自: 北京林业大学学报] 相似文献
16.
Kana Yamashita Yasuhiko Hirakawa Shuetsu Saito Hiroshi Nakatani Motoyoshi Ikeda Masamitsu Ohta 《Journal of Wood Science》2012,58(3):259-266
To investigate the factors affecting the surface-check variation in boxed-heart square timber of sugi (Cryptomeria japonica), surface checks formed by the conventional kiln drying were compared for two stem heights of five cultivars with different wood properties. The total length and average length of the surface checks were greater at the upper part of the stems for all the cultivars. This might be caused by more sapwood at the upper part of the stem, and large drying stresses between the outer sapwood and the inner heartwood. The cultivars, in which tangential shrinkage was large owing to small microfibril angle, formed longer surface checks and smaller bow. There was a positive relationship between surface-check length and tangential shrinkage. The heartwood percentage and tangential shrinkage were thought to be important factors affecting the surface-check variation in sugi boxed-heart square timber. 相似文献
17.
Naohiro Takaku Dr. Don-Ha Choi Keigo Mikame Tomoya Okunishi Shiro Suzuki Hideo Ohashi Toshiaki Umezawa Mikio Shimada 《Journal of Wood Science》2001,47(6):476-482
Heartwood ofChamaecyparis obtusa contains significant amounts of a dibenzylbutyrolactone lignan, hinokinin (8). This investigation demonstrated that the contents of 8 and a norlignan, hinokiresinol (12), were higher in the heartwood region than in the sapwood, indicating their nature of being heartwood extractives. Eleven lignans — xanthoxylol (1), 7-oxohinokinin (2), savinin (3), dihydrosesamin (4), isoactifolin (5), sesamin (6), piperitol (7), hinokinin (8), pluviatolide (9), haplomyrfolin (10), and rnatairesinol (11) — were isolated from young shoots ofChamaecyparis obtusa cv. Breviramea. Eight lignans (1, 2, 4, 5, 7, 9,10, and11) were isolated from this plant for the first time. Chiral high-performance liquid Chromatographie analysis showed that8, 9, 10, and11, were found to be levorotatory and optically pure (>99% e.e.). Based on the chemical structures of the isolated lignans, possible biosynthetic pathways of8 are discussed.Parts of this report were presented at the 44th annual meeting of the Japan Wood Research Society, Nara, April 1994; the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996; and the 44th Lignin Symposium, Gifu, October 1999 相似文献
18.
Blackening in heartwood was investigated in relation to the metal contents and the moisture content in xylem of about 50-year-old seedling sugi (Cryptomeria japonica D. Don) planted in a steeply sloped stand in Okutama district (Itsukaichi Tokyo), where blackened heartwood is frequently found. The potassium, calcium, iron, and manganese contents were examined in the variously blackened heartwood and normal heartwood by an atomic absorption method. It was recognized that potassium increased relative to the degree of the blackening of heartwood, resulting in a significant correlation between them. This finding implies that an increase in potassium has an important role in the blackening of heartwood. Moisture content has a tendency to increase in the blackened heartwood, so it seems that the large accumulation of potassium is associated with the high moisture content in heartwood.This work was presented at the 43rd Annual Meeting of the Japan Wood Research Society at Morioka, August 1993 相似文献
19.
Three-dimensional distribution of water in the heartwood of Cryptomeria japonica D. Don was observed by soft X-ray photography. The within-tree variation in the distribution of “wet areas” (water-accumulated
areas in heartwood) was enormous, as was the variation among trees. Although we found no universal pattern of changes in wet
area distributions along the stem axes of all trees, similarities among individual trees within each cultivar and clone were
observed. The difference between the two kinds of wetwood in C. japonica – genetically defined wetwood and secondarily induced wetwood – is discussed, as is the use of soft X-ray photography in Japanese
tree breeding programs.
Received: December 21, 2001 / Accepted: May 1, 2002
Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, Japan, April 1996
Correspondence to:R. Nakada 相似文献
20.
Camilla Wikstrm 《Forest Pathology》1975,5(6):349-356
In contrast to the woodrotting fungi which can only attack Populus tremula after felling, Phellinus tremulae successfully invades the central part of the living tree. Possible causes for this difference were investigated. It was found that sterile wood samples were decomposed more rapidly by saprophytic fungi than by parasitic fungi. With both types of fungi, heartwood was more resistant to decay than sapwood. It is postulated that living sapwood inhibits infection by most woodrotting fungi, but that P. tremulae can successfully overcome this barrier. This postulate cannot be confirmed by experiments using sterilized wood samples. 相似文献