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Wataru Aoyama Shinya Sasaki Shigeki Matsumura Thoru Mitsunaga Hirofumi Hirai Yuji Tsutsumi Tomoaki Nishida 《Journal of Wood Science》2002,48(6):497-504
Two peroxidases, CWPO-A and CWPO-C, were isolated from the cell walls of poplar (Populus alba L.) callus culture. The cationic CWPO-C showed a strong preference for sinapyl alcohol over coniferyl alcohol as substrate. Thus, the monolignol utilization of CWPO-C is unique compared with other peroxidases, including anionic CWPO-A and horseradish peroxidase (HRP). CWPO-C polymerized oligomeric sinapyl alcohol (S-oligo) and sinapyl alcohol, producing a polymer of greater molecular weight. In contrast, HRP, which is specific to coniferyl alcohol, produced sinapyl alcohol dimers, rather than catalyzing polymerization. Adding coniferyl alcohol as a radical mediator in the HRP-mediated reaction did not result in S-oligo polymerization. This report shows that CWPO-C is an isoenzyme specific to sinapyl alcohol that polymerizes oligomeric lignols. Its catalytic activity toward oligomeric lignols may be related to the lignification of angiosperm woody plant cell walls.Part of this study was presented at the 45th Lignin Symposium, Matsuyama, October 2000 相似文献
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对醇类燃料特性及其应用现状的分析研究表明,低浓度醇类燃料适合在不改变发动机结构的情况下使用;结合二冲程小型发动机的特点和使用情况,得出低浓度醇类燃料适合作为其替代燃料;通过对醇类燃料作为二冲程小型发动机燃料的可行性分析可知,燃烧醇类混合燃料可提高二冲程小型发动机的能量利用率、减少其尾气排放和降低排放温度。 相似文献
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Marjamaa K Kukkola E Lundell T Karhunen P Saranpää P Fagerstedt KV 《Tree physiology》2006,26(5):605-611
We partially purified peroxidase isoform fractions from xylem extracts of a gymnosperm, Norway spruce (Picea abies (L.) Karst.), and an angiosperm, silver birch (Betula pendula Roth.), to determine the participation of xylem-localized peroxidases in polymerization of different types of lignin in vivo. Several peroxidase fractions varying in isoelectric point values from acidic to basic were tested for their ability to catalyze the oxidation of the monolignols coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol in vitro. All of the xylem peroxidases extracted from Norway spruce and most of those from silver birch showed the highest rate of oxidation with coniferyl alcohol in the presence of hydrogen peroxide. The exception was an acidic peroxidase fraction (pI 3.60-3.65) from silver birch that exhibited higher oxidation activity for sinapyl alcohol than for coniferyl alcohol. For the xylem enzyme fractions extracted from silver birch, the ability to oxidize the artificial phenolic substrate syringaldazine coincided with high specific activity for sinapyl alcohol. Therefore, we conclude that the acidic, neutral and basic xylem peroxidases of Norway spruce all function in the synthesis of guaiacyl-type lignin, whereas in silver birch the acidic peroxidases preferentially oxidize sinapyl subunits. The latter provides a mechanism for synthesis of guaiacyl-syringyl lignin typical of tracheid cell walls in angiosperm trees. 相似文献
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采用Caco-2细胞模型,分析了青钱柳Cyclocarya paliurus叶水提物、醇提后的水提物、95%醇提物、乙酸乙酯萃取物和正丁醇萃取物5种不同提取物对Caco-2细胞活力的影响及对Caco-2细胞上麦芽糖酶、蔗糖酶、乳糖酶3种二糖酶活性的抑制作用。结果表明,5种不同提取物中除95%醇提物对Caco-2细胞活力产生一定影响外,其余4种提取物对Caco-2细胞基本无毒性,在200 mg·L-1浓度提取物范围内培养24～72 h后细胞仍能保持较高活力;对3种二糖酶活性抑制作用效果最好的为醇提后的水提物,尤其是对蔗糖酶和乳糖酶的抑制作用更为明显,最高的抑制率分别达到76.35%和60.13%,其次为乙酸乙酯萃取物,对乳糖酶的抑制率最高达54.41%。从青钱柳叶不同方法提取物的制备流程说明多糖类或中等极性的黄酮甙类有可能是青钱柳叶中抑制二糖酶活性的主要组成成分。 相似文献
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核桃楸外果皮提取物的化感作用及成分分析 总被引：4，自引：0，他引：4
采用常规提取法浸提核桃楸外果皮的化感作用成分。研究结果表明,核桃楸外果皮乙醇提取物和乙酸乙酯萃取相对3种受体植物青菜、萝卜和紫花苜蓿具有化感作用(抑制萌发和抑制生长作用)。化感作用随提取物浓度增大而增大。采用GC-MS分析核桃楸外果皮乙醇提取物中乙酸乙酯萃取相的化学组成和相对含量。分析结果表明,核桃楸外果皮乙醇提取物中乙酸乙酯萃取相的主要化学成分为5-羟基-1,4-萘醌(胡桃醌),GC含量31.20%;正十六酸,GC含量9.99%;7-甲氧基-1-四氢萘酮,GC含量7.99%;1,5-萘二酚,GC含量7.15%;2,6-二甲氧基苯酚,GC含量4.36%;4-丁氧基苯醛;GC含量3.23%;5-羟甲基-2-呋喃醛,GC含量2.96%;二聚1,3-二羟基丙酮,GC含量2.94%;丙三醇,GC含量2.77%;1(3H)-异苯并呋喃酮,GC含量2.57%。 相似文献
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Distribution of lignin and lignin precursors in differentiating xylem of Japanese cypress and poplar
Lignin is an integral component of the cell wall of vascular plants. The mechanism of supply of lignin precursors from the cytosol into the cell wall of differentiating xylem has not yet been elucidated. The present study showed that a certain amount of coniferyl alcohol glucoside (coniferin) occurred in the differentiating xylem of Japanese cypress (Chamaecyparis obtusa), as previously reported in gymnosperms. Coniferin content peaked in the early stages of secondary wall formation and decreased during lignification. In contrast to gymnosperms, coniferin content was limited in the differentiating xylem of poplar (Populus sieboldii × Populus grandidentata). Moreover, coniferyl alcohol was not detected in all specimens. In the differentiating xylem of poplar, a higher amount of sinapyl alcohol occurred than glucoside (syringin). However, the phloem contained syringin and not sinapyl alcohol. The sinapyl alcohol content in the xylem peaked in the cells with ceasing cell wall formation, and decreased gradually towards the boundary of the annual ring, where the lignin content kept increasing. Sinapyl alcohol in the differentiating xylem of poplar may be used for the lignification of the xylem. 相似文献
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Sanni Raiskila Kurt Fagerstedt Tapio Laakso Pekka Saranpää Mia Löija Leena Paajanen Riitta Mahlberg Anne-Christine Ritschkoff 《Wood Science and Technology》2006,40(8):697-707
It is known that active peroxidase isozymes exist in mature wood of Norway spruce (Picea abies L. Karst.) and that they remain active for years and are found even in the heartwood (in Scots pine), where all cellular activity has ceased. This peroxidase activity was utilised in the impregnation of wood blocks with a natural monolignol, coniferyl alcohol and hydrogen peroxide. The hypothesis was that the internal wood peroxidases would oxidise the added monolignol and bind it stably into the cell wall matrix, which could hinder fungal decay. Since coniferyl alcohol is not very soluble in water, the impregnation was done under vacuum with an acetone–water solution containing 10% coniferyl alcohol and 0.4 mM H2O2 at room temperature (ca. 0.02 g of coniferyl alcohol was added to 1 g of wood). After impregnation, dimers of coniferyl alcohol and free coniferyl alcohol were found in acetone extracts with GC–MS analysis. Penetration of coniferyl alcohol and non-extractable reaction products were studied from the wood blocks with FTIR PAS technique. The wood samples treated were also subjected to a fungal decay test with Coriolus versicolor. This treatment hindered fungal decay in a 60-day experiment and led to a dry weight loss of 8.8% in comparison with 19.9% in the control. The reactions of coniferyl alcohol and H2O2 in the presence of peroxidases are discussed as well as the use of monolignols to increase wood decay resistance. 相似文献
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以糠醇和邻苯二甲酸酐为原料，通过控制酯化反应条件，制备了糠醇邻苯二甲酸单酯。有关该化合物的合成及相关数据未见文献报道。 相似文献
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Carai MA Agabio R Bombardelli E Bourov I Gessa GL Lobina C Morazzoni P Pani M Reali R Vacca G Colombo G 《Fitoterapia》2000,71(Z1):S38-S42
The present paper briefly reviews the most relevant experimental data on the reducing effect of some medicinal herbs on voluntary alcohol intake in animal models of alcoholism. Pueraria lobata, Tabernanthe iboga, Panax ginseng, Salvia miltiorrhiza and Hypericum perforatum proved to be effective in decreasing alcohol consumption. Reduction of alcohol absorption from the gastrointestinal system appears to be a common feature among most of the above plants. These data suggest that medicinal plants may constitute novel and effective pharmacotherapies for alcoholism. 相似文献
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沙芥全草总黄酮提取方法及含量测定的研究 总被引：13，自引：0，他引：13
本文采用碱提酸沉法、超声波提取法、甲醇直接提取法、乙醇提取法和热水浸提法对沙芥全草总黄酮进行了提取方法的选择,同时采用硝酸铝比色法进行了总黄酮含量的测定,结果表明:(1)各种方法的提取效率依次为:碱提酸沉法>超声波提取法>甲醇直接提取法>乙醇提取法>热水浸提法;(2)碱提酸沉法提取沙芥总黄酮的提取效率较高,其精密度好,回收率高,适合对沙芥总黄酮的提取,同时采用硝酸铝比色法对总黄酮含量进行测定,其精密度也较高,并测得沙芥全草总黄酮含量为4.8049mg/g,证明其是一种值得开发的药用植物资源。 相似文献
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Effect of coniferyl alcohol addition on removal of chlorophenols from water effluent by fungal laccase 总被引：2，自引：0，他引：2
Nam-Seok Cho Jerzy Rogalski Magdalena Jaszek Jolanta Luterek Maria Wojtas-Wasilewska Elzbieta Malarczyk Monika Fink-Boots Andrzej Leonowicz 《Journal of Wood Science》1999,45(2):174-178
The effect of coniferyl alcohol on removal of chlorinated phenols from a water environment byRhizoctonia praticola andCerrena unicolor laccases was studied. At optimal conditions in which 7 mM coniferyl alcohol and laccase were added to chlorinated phenols over 20h, about 34% of the radioactivity of 4-chlorophenol, 57% of 2,4-dichlorophenol, 66% of 2,4,5-trichlorophenol, and 85% of pentachlorophenol were removed from the supernatants, compared to the level without laccase activity. After 12-h incubation periods at the optimal concentrations of coniferyl alcohol and laccase (added simultaneously), the fast first phase of chlorophenol removal was complete in 1 h, and eventually coniferyl alcohol enhanced the removal of 4-chlorophenol by 40%, 2,4-dichlorophenol by 54%, 2,4,5-trichlorophenol by 60%, and pentachlorophenol by 76%. 相似文献
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Ulla Westermark 《Wood Science and Technology》1982,16(1):71-78
Summary The reaction of enzymatically generated superoxide radical with coniferyl alcohol in aqueous solution at pH 8.0 was studied. In the absence of calcium (II) no reaction occurred, but with a calcium (II) concentration of about 50 mM or more, coniferyl alcohol was oxidized by the superoxide radical. Dehydrodiconiferyl alcohol and pinoresinol were identified in the reaction mixture. From this result it is concluded that in the presence of calcium (II) the superoxide radical can achieve a one electron oxidation of coniferyl alcohol.It is suggested that a superoxide-generating enzyme outside the cell wall is responsible for the lignification. This suggestion is based on knowledge of the pore structure of wood cell walls, the high calcium concentration in non-lignified cells, the course of lignification and the existence of superoxide-producing enzyme systems in plant cell walls.The author gratefully acknowledges the skiful technical assistance of Mr. Johan Lindberg 相似文献
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对山楂果酒酿制过程中总糖、酒度和总酸等主要成分变化规律的研究表明,前发酵初期总糖下降速度与酒度上升速度都较快,随后逐渐减缓,总酸在前发酵过程中呈上升趋势。在后发酵过程中,前期总糖下降与酒度上升均较缓慢,随后加快,总酸变化不大。在整个发酵过程中总糖下降与酒度上升规律一致。陈酿期间酒度与总糖变化很小,总酸有下降趋势。 相似文献
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Furfuryl alcohol has a sufficiently small molecular size, which allows impregnation into wood and can be polymerized in the cell walls. Polymerization can be accomplished using a catalyst, heat or penetrating radiation. This research illustrates a natural wood polymer composite (NWPC) that was obtained under the catalytic effect of borates. Furfuryl alcohol (FA) and borates were mixed at different ratios before treatment. When borates alone are used, they were totally leached from wood after cyclic leaching periods. However, this was not encountered with the mixture of furfuryl alcohol and borates. Furfuryl alcohol considerably improved antiswelling efficiency by about 85% for both Japanese cedar ( Cryptomeria japonica) and Scots pine ( Pinus sylvestris L.) wood specimens. Results of the leaching tests of borate indicated that boric acid readily lost its boron content in the early cycles of the leaching periods and the highest leaching rate of boron was observed at the first leaching cycle (512 ppm). When furfuryl alcohol mixed with borates, boron was released to the leaching water at slower amounts, suggesting the possibility of longer protection of treated wood in service. 相似文献
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《Fitoterapia》2013
The Curcuma zedoaria rhizome has been used traditionally to treat gastrointestinal diseases as an aromatic stomachic drug, and this is currently used to treat alcohol-induced loss of appetite and nausea in Japan. We examined the effects of various fractions and isolated compounds on alcohol-induced drunkenness and blood alcohol concentrations in mice. The 30% ethanol-extract (1000 mg/kg) of C. zedoaria rhizome prevented drunkenness 60 and 120 min after 40% alcohol administration. The n-hexane-soluble fraction (300 mg/kg) and an isolated compound (3, 10 or 30 mg/kg) prevented drunkenness at 30, 60 or 120 min. The extract, n-hexane-soluble fraction and isolated compound reduced the elevation in blood alcohol concentrations 30 and 60 min after 40% alcohol administration. The isolated compound (10 and 30 mg/kg) enhanced liver ADH activity 30 and 60 min after 40% alcohol administration. The compound was identified as curcumenone by a direct comparison of 1H- and 13C-NMR spectral data. In conclusion, the protective effect of the C. zedoaria extract on drunkenness might be due to an active substance, curcumenone, and decreases in the elevation of blood alcohol concentrations through increased liver alcohol dehydrogenase activity. 相似文献
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光肩星天牛对干旱胁迫下复叶槭挥发物的嗅觉反应 总被引：2，自引：0，他引：2
对干旱胁迫下3a生复叶槭的挥发物进行了鉴定。当复叶槭受到干旱胁迫时，9种化合物释放量升高(包括：丁醇、戊醇、反—2—己烯—1—醛、顺—3—己烯—1—醇、戊醛、戊酸、己醛、己酸、苯乙酮)，而长叶烯释放量降低：复叶槭复水后苯乙酮升高，但其他挥发物释放量降低。通过GC—EAD检测了光肩星天牛对其中某些化合物的触角电位反应，并使用诱捕器和人工合成单体进行了田间生测实验。丁醇、戊醇和顺—3—己烯—1—醇能引起光肩星天牛的触角反应，这一结果在田间实验中得到了证实。这表明干旱胁迫在光肩星天牛选择寄主植物方面起着重要作用。 相似文献