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Summary The separation of unsaponifiable from saponifiable constituents of tall oil fatty acids by different methods has been attempted. After catalytic hydrogenation of the fatty acids it was possible to separate to a great extent the saturated solid acids and the rosin acids present from other components.After separation the different fractions were investigated by means of GC, TLC, NMR and UV analyses. As a result of these measurements it was obvious that the acid-poor fraction consisted of unsaturated acids, several aromatic compounds, partly of phenolic structure and unidentified materials. The concentration of the aromatic compounds was estimated at about 2% by weight. The hydrogenated and filtered fraction was methylated and submitted to a GC/MS analysis. A number of aliphatic and aromatic compounds could be identified. 相似文献
3.
Ivy Stone Jean-Pierre Ouellet Luc Sirois Marie-Josée Arseneau Martin-Hugues St-Laurent 《Forest Ecology and Management》2008
We investigated immediate, medium and long-term effects of logging on arboreal lichen biomass in old-growth balsam fir forests (Abiesbalsamea (L.) Mill.) in the highlands of Québec's Gaspé Peninsula using three complementary approaches. Firstly, we estimated the immediate loss of lichen biomass following logging and the annual lichen litterfall from remnant trees over 2 post-logging years. Treatments included selection cutting at three intensities (25, 30, 35%), diameter-limit cutting and cutting with protection of regeneration and soils (CPRS). Among studied treatments, we found that CPRS and diameter-limit cutting removed almost all the standing lichen biomass, while selection and partial cut allowed an immediate retention of ∼40–60% of the initial lichen biomass. Our results also suggested that the impact of logging on lichen litterfall rates were higher in silvicultural treatments (3–8.5%) compared to controls (1–2%); litterfall rates did not differ after 1 or 2 years post-treatment. Secondly, we evaluated medium-term effects by comparing pre-harvest fruticose lichen biomass data with data collected at the same site 4 years after experimental thinning operations. Mean fruticose lichen biomass did not change 4 years post-harvest. However, Bryoria spp. biomass did increase relative to Alectoriasarmentosa while Usnea spp. remained unchanged. Finally, the long-term logging effects were assessed by evaluating fruticose lichen biomass along a forest chronosequence in stands aged 30, 50, 70 and 90 years. Lichen biomass increased as a function of time for all genera, especially Alectoria. Logging activities result in direct losses of lichen biomass, but careful selection cutting that retains large lichen bearing trees and maintains post-harvest conditions not detrimental to lichen growth, particularly for Bryoria spp., can ensure a substantial biomass of lichens post-harvest. Such measures may ultimately contribute to maintaining woodland caribou herds that rely on arboreal lichens. 相似文献
4.
不同温度段苹果枝木醋液化学组成、抑菌及抗氧化活性比较 总被引：10，自引：0，他引：10
以苹果枝为原料,采用干馏法分3个温度段收集苹果枝木醋液.用GC-MS法分析各温度段苹果枝木醋液的有机成分,并对木醋液的抑菌活性和抗氧化活性进行测定.结果表明:3个温度段苹果枝木醋液的化学组成不同,含量差别较大,低温度段(100～200 ℃,AP_1)中检出45种物质,占整个出峰面积的91.26%,其中酚类含量为51.33%,有机酸酸含量为18.50%,酮类含量为8.98%,呋喃类含量为7.23%;中间温度段(200～310 ℃,AP_2)检出47种物质,占整个出峰面积的95.35%,其中酚类含量为24.69%,有机酸酸含量为40.05%,酮类含量为7.52%,呋喃类含量为12.81%;高温度段(310～500 ℃,AP_3)检出47种物质,占整个出峰面积的93.00%,其上述物质含量依次为34.66%,28.37%,12.49%和6.93%.有机酸在中间温度段木醋液中含量最多,酚类在低温度段含量最多.3个温度段的苹果枝木醋液均有抑菌和抗氧化活性,其抑菌活性顺序为AP_2＞AP_3＞AP_1,AP_2的抑菌活性最强,且与AP_1和AP_3的差异显著,其中对植物病原菌的EC_(50)为2.43～5.27 Mg·mL~(-1);抗氧化活性大小顺序为AP_1＞AP_3＞AP_2,且存在显著的量效关系,AP_1的抗氧化活性最强,均高于抗坏血酸和BHT.初步分析AP_2较强的抑菌活性和AP_1较强的抗氧化活性分别与其中高含量的有机酸和酚类物质有关. 相似文献
5.
《Forest Policy and Economics》2005,7(1):39-52
This paper examines the tradeoffs between different uses of forests in three communes in the mountain region in northern Sweden. The most important uses of the forests include timber production, preservation of biodiversity, reindeer grazing and recreation. Management outcomes with respect to the different uses are measured in terms of the net present value (NPV) of timber production profits, the sum of deadwood volume over time, the minimum periodic lichen production, and a minimum periodic recreation index (RI). The analysis shows that the forests can be managed to achieve dramatically different mixes of NPV, deadwood volume, and lichen production, whereas the RI varies only within a narrow range. To maximize the NPV, lichen production would reduce by 40% from its maximum level, and the volume of deadwood would be close to 0 in period 2 and thereafter. Maximization of deadwood volume would lead to the maximum lichen production, while the NPV would fall below 0. Maximization of lichen production reduces the NPV by at least 20%, and could reduce the amount of deadwood by up to 75%. When lichen production is restricted to its maximum, there is a wide range of possible choices with respect to the mix of the NPV and deadwood volume. The marginal cost of increasing the deadwood volume ranges from 1.12 to 20 SEK/m3. The choice between lichen production and deadwood volume is most flexible when the NPV is fixed at approximately 93% of its maximum. 相似文献
6.
We previously showed that ethanolic extracts of spores of Ganoderma lucidum inhibit tumor cell proliferation and induce apoptosis of HL-60 cells. The active constituents appeared to be long-chain fatty acids, particularly carbon-19 (C-19) fatty acids which have not been reported in spores of Ganoderma lucidum. In the present study, two of these C-19 fatty acids which are key compounds in the activities, were identified as their 2-naphthyl ester derivatives after esterification of a mixture of fatty acids obtained from the spores. The active compounds were determines as nonadecanoic acid and cis-9-nonadecenoic acid. The location of the double bond of cis-9-nonadecenoic acid was demonstrated by GC-MS analysis, based on the fragmentation pattern of the adduct prepared from the fatty acid and dimethyl disulfide. 相似文献
7.
《Scandinavian Journal of Forest Research》2012,27(2):90-98
Abstract The re-establishment rates of reindeer lichen following conventional soil preparation by disc trenching and gentle soil preparation using HuMinMix apparatus were calculated from data acquired in surveys of 17 Pinus–lichen clear-cut stands in northern Sweden conducted 1–15 years after the treatments. The maximum lichen cover and biomass recorded in areas scarified by disc trenching were 29% and 24% of the lichen cover and biomass measured in adjacent intact lichen mats in the surveyed stands after 15 years. By contrast, 9 years after scarification, the corresponding percentages measured in areas disturbed by the HuMinMix treatment were 91% and 100%, respectively. According to calculated linear regressions, the reindeer lichen cover could be completely re-established just one decade after HuMinMix treatment. Ground lichen diversity in the scarified areas was also inventoried. The significant increase in lichen diversity for HuMinMix, especially of early-successional species, could explain the more rapid re-establishment of late-successional lichens (e.g. Cladonia stellaris spp.), compared with disc trenching. Thus, the study demonstrates that both the degree of initial disturbance and the re-establishment rate of reindeer lichen must be considered when estimating the effects of scarification on lichen loss for reindeer grazing over time. 相似文献
8.
The purpose of this study was to investigate the modulating effects of phyllanthin and hypophyllanthin on vascular tension, using in the in vitro model of isolated rat aorta. Our results indicated that both phyllanthin and hypophyllanthin significantly relaxed the sustained contraction induced by phenylephrine (PE) in a concentration-dependent manner. In addition, endothelial removal had no significant influence on the vasorelaxation responses of the aortic rings toward these two compounds. Furthermore, both compounds inhibited the contraction of aortic muscle provoked by either PE (1 μM) or KCl (40 mM) as well as the spontaneous contraction of the Ca2+-depleted muscle. In high K+- Ca2+ free solution, phyllanthin (100 μM), but not hypophyllanthin, significantly inhibited the contractile responses upon cumulative addition of CaCl2. Both compounds (100 μM) significantly inhibited PE-induced contraction in Ca2+-free condition, but could not affect caffeine-induced contraction. Taken together, phyllanthin and hypophyllanthin could modulate the vascular tension via the endothelium-independent mechanisms. The modulating effects of both compounds were possibly involved with the blockade of Ca2+ entry into vascular smooth muscle cells and inhibition of PE-mediated Ca2+ release from sarcoplasmic reticulum. 相似文献
9.
为研究流苏树种子的成分,探讨不同溶剂提取流苏树种子成分的差异。本研究分别采用石油醚、二氯甲烷和丙酮提取流苏树种子成分,以GC-MS联用技术对其化学成分进行分析。结果显示:石油醚提取物含有10种烷烃类、16种酯类和1种酰胺类化合物,占色谱总流出峰面积的91.36%,其中十六烷酸甲酯(10.83%)、反式-13-十八碳烯酸甲酯(60.67%)和6-十八碳烯酸甲酯(11.29%)含量较高;二氯甲烷提取物含有10种烷烃类、4种酯类、2种酸类和3种烯烃类化合物,占色谱总流出峰面积的80.85%,其中1,2-二甲基环戊烷(8.21%)、十六烷酸(14.51%)、(Z,Z)-9,12-十八碳二烯酸(35.93%)等化合物含量较高;丙酮提取物含有10种烷烃类、11种酯类和2种烯烃类化合物,占色谱总流出峰面积的98.23%,其中十六烷酸甲酯(14.07%)、(Z,Z)-9,12-十八碳二烯酸甲酯(44.65%)、(E)-9-十八碳烯酸甲酯(12.27%)和十八酸甲酯(15.62%)含量较高。石油醚和丙酮提取酯类的效果优于二氯甲烷,在提取酸类和烷烃类化合物时,二氯甲烷效果更佳。不同的溶剂提取流苏树种子成分的组成和含量存在一定的差异。 相似文献
10.
Ewa Stefańska-Krzaczek Wiesław Fałtynowicz Bartłomiej Szypuła Zygmunt Kącki 《European Journal of Forest Research》2018,137(4):419-431
In Central Europe, deciduous forests are the dominant community type and lichen pine forests are restricted to certain areas with extremely nutrient-poor and xeric soil types. In recent decades, a retreat of vegetation of oligotrophic habitats has been observed in Central Europe. In this study, we assessed changes of lichen pine forests in Poland: within the main area of the range in Central Europe. We used two sets of data collected at a local and regional (nation-wide) scale. On the basis of data from semi-permanent plots, we examined changes in the structure and species composition of lichen pine forests over 33 years at the local scale (between 1975 and 2008). To compare trends at the regional scale, we used data collected in the Polish Vegetation Database (PVD). For identification of lichen pine forests we determined a group of co-occurring Cladonia species. We analyzed differences in species richness and vegetation structure at the regional scale in tree time periods (1) between 1951 and 1969, (2) 1970 and 1989, and (3) 1990 and 2011. We found that changes in lichen pine forests are primarily quantitative at both scales. Our results indicate that the abundance of Cladonia species is limited by strong competitors, i.e., vascular plants and bryophytes, which may be explained by eutrophication and climate warming. Only pine forests with a minor abundance of lichens have chances to persist in the vegetation of Central Europe, while the most valuable communities with high abundance of indicators will disappear. Though an assessment of the total decrease in the area of lichen pine forests is not possible with the available regional data, local observations indicate a large decline in the area of lichen pine forests in Central Europe. Their conservation seems to be a serious challenge, because it is difficult to provide optimal conditions for all indicators. 相似文献
11.
Japanese beech (Fagus crenata) wood was treated in supercritical water at 380°C/30 MPa and 380°C/100 MPa. The hydrolysate (water-soluble portion) was found
to contain the fragmented and dehydrated compounds of sugars and organic acids. Although organic acids are expected to be
utilized for methane fermentation, the effects of the fragmented and dehydrated compounds of sugars on methane production
are not known. The objective of this study is, therefore, to elucidate the potential of supercritical water treatment as a
new pretreatment for methane production by evaluating the methane fermentability of the hydrolysate. From the methane fermentation
tests for those model compounds with digested sludge, it is found that methane was produced not from the fragmented and dehydrated
compounds but from the organic acids. The yield of methane from the hydrolysate obtained at 380°C/30 MPa was higher than that
from the hydrolysate obtained at 380°C/100 MPa because the former contains more organic acids than the latter. The maximum
yield of methane was seven times greater compared to the untreated wood, indicating that the supercritical water treatment
is effective for enhancing the productivity of methane from wood. 相似文献
12.
Eric M. Rominger Lydia Allen-Johnson John L. Oldemeyer 《Forest Ecology and Management》1994,70(1-3):195-202
To better understand the effects of partial cutting on arboreal lichen production within woodland caribou (Rangifer tarandus caribou) habitat, lichen was hand picked from 1228 branches on 307 subalpine fir (Abies lasiocarpa) trees in Idaho (ID), and in British Columbia (BC). Lichen biomass from partially cut stands was compared with biomass on trees from adjacent uncut stands at each site. Arboreal lichen biomass did not differ significantly between uncut and partially cut stands. Total number of branches per tree did not differ significantly between uncut and partially cut stands. Live branches had more lichen than dead branches. Species composition of arboreal lichen changed in partially cut stands compared with adjacent uncut stands. The ratio of live to dead branches was substantially different within the BC partial cut. 相似文献
13.
《Scandinavian Journal of Forest Research》2012,27(3):219-230
Abstract Knowledge of the canopy lichen flora of managed forests is poor, but needs more focus since, for example, slash (tops, branches and twigs) harvest for biofuel may pose a threat to epiphytic lichen diversity. This study compared lichen species richness, density and composition between stems, tops, branches and twigs of mature Norway spruce (Picea abies) and aspen (Populus tremula) in managed boreonemoral forests in south–central Sweden. The stems were also compared with the slash fractions pooled together. All comparisons were made separately for each tree species. In total, 30 lichen species were found on Norway spruce and 46 on aspen. No significant differences in species richness or species density between fractions were found for Norway spruce, whereas aspen tops were significantly less species rich and species dense than the other fractions. Moreover, aspen slash was significantly more species dense than the stem. The lichen species composition of the stems clearly differed from that of the tops, branches and twigs in both tree species. Thus, lichen communities other than those removed with stems by conventional forestry are removed from the stands owing to slash harvest. However, these species are rather common and widespread in Sweden. The impact of slash harvest on the epiphytic lichen flora may therefore be of minor importance in forests established after clear-cutting or on former arable land. 相似文献
14.
研究阔叶树上的6种木材白腐菌火木层孔菌、粗毛盖菌、偏肿拟栓菌、三色革裥菌、冬拟多孔菌和血红密孔菌对山杨材腐朽前后木材中游离酚酸种类和含量的变化情况.结果表明:受6种白腐菌腐朽后的山杨木材中酚酸的种类和含量各不相同,在山杨材被分解120 d后,偏肿拟栓菌、三色革裥菌、血红密孔菌和冬拟多孔菌的9种游离酚酸总含量远大于粗毛盖菌和火木层孔菌的9种游离酚酸总含量,表明前4种对木质素分解能力较强的菌种获得了较高含量的酚酸;但从9种游离酚酸总的含量上看,与各菌种对木材和木质素的分解百分率不尽相同,初步分析的原因表明在木质素被分解的过程中除了有这9种游离酚酸产生以外,可能还会产生其他的游离酚酸以及苯环二聚体、三聚体和各种寡聚体以及杂环的形式,所有这些苯环结构总体造成了对木质素分解百分率的差异. 对9种酚酸进行分析测试,只构成对木质素分解的一部分,不足以用来解释对木质素的全部分解能力,其他的酚酸和游离酚酸以外的苯环结构还有待进一步研究分析测试;从各种游离酚酸单个含量上看,各种白腐菌的种类和含量都各不相同,表明不同白腐菌对同一木质纤维基质的分解途径、中间降解产物各不相同.另外,未腐朽的木材中本身就含有一些微量的酚酸成分,这些酚酸在生物分解过程中会降解和转化成其他成分, 是否有可能转化成其他种类的酚酸还有待进一步证明. 相似文献
15.
《Fitoterapia》2013
A series of 11 flavonol glucuronides were isolated from the herb of Polygonum aviculare L. (Ph.Eur) of which 8 were reported for the first time from the Polygonum species. Three acetylated kaempferol and isorhamnetin glucuronides were isolated from a natural source for the first time. All compounds, including the new ones, were characterized using 1D and 2D NMR spectra as well as high resolution mass spectrometry. The influence of all isolated compounds on the production of reactive oxygen species, as well as on elastase release by human neutrophils, was evaluated in in vitro studies. The results showed that all investigated compounds at physiologically achievable concentrations within the range of 0.5–10 μM significantly inhibited the production of reactive oxygen species as well as elastase release in human neutrophils model and should be considered as responsible for anti-inflammatory activity of the P. aviculare herb. The chemotaxonomic value of isolated compounds was also discussed. 相似文献
16.
Rios MY López-Martínez S López-Vallejo F Medina-Franco JL Villalobos-Molina R Ibarra-Barajas M Navarrete-Vazquez G Hidalgo-Figueroa S Hernández-Abreu O Estrada-Soto S 《Fitoterapia》2012,83(6):1023-1029
The aim of the current study was to investigate the vasorelaxant activity of five structurally-related triterpenic acids namely ursolic (1), moronic (2), morolic (3), betulinic (4) and 3,4-seco-olean-18-ene-3,28-dioic (5) acids. The vasorelaxant effect of compounds 1-5 were determined on endothelium-denuded and endothelium-intact rat aortic rings pre-contracted with noradrenaline (0.1 μM). All compounds showed significant relaxant effect on endothelium-intact vessels in a concentration-dependent manner (p<0.05). Ursolic, moronic and betulinic acids were the most potent vasorelaxant agents with 11.7, 16.11 and 58.46 μM, respectively. Since vasorelaxation was blocked by L-NAME, while indomethacin did not inhibit the effect, endothelium-derived nitric oxide seems to be involved in triterpenic 2 and 3 mode of action. Compounds 1-5 were docked with a crystal structure of eNOS. Triterpenes 1-5 showed calculated affinity with eNOS in the C1 and C2 binding pockets, near the catalytic site; Ser248 and Asp480 are the residues that make hydrogen bonds with the triterpene compounds. 相似文献
17.
Volatile organic compound emission from holm oak infested by gypsy moth larvae: evidence for distinct responses in damaged and undamaged leaves 总被引：3，自引：0，他引：3
Foliage of Quercus ilex L. (holm oak), a widespread Mediterranean species, constitutively emits large quantities of a complex genotype-dependent mixture of volatile organic compounds (VOCs). During a mass outbreak of gypsy moth (Lymantria dispar L.) in southern France, we examined the effects of gypsy moth feeding on VOC production from whole apices and single leaves of Q. ilex. Feeding induced the emission of new VOCs at rates up to 240 ng m(-2) s(-1) (16% of the total VOC release), which mainly consisted of sesquiterpenes, a homoterpene and a monoterpene alcohol. The new compounds were emitted after a delay of several hours following infestation and their production declined rapidly when caterpillars were removed. Undamaged leaves of infested trees emitted new VOCs, but with a different composition to those of damaged leaves and at lower rates. Neither caterpillars nor caterpillar excrement released VOCs. Emission of constitutive VOCs by undamaged leaves of infested trees temporary increased by up to 30%, whereas, in damaged leaves, they remained stable and decreased after some days when necrotic spots occurred around the feeding sites. In continuous light and at constant temperature, emissions of new VOCs showed a marked diurnal cycle, whereas those of constitutive VOCs did not. The results suggest that induced VOCs make a significant contribution to the atmospheric VOC load and may mediate trophic interactions. The observed differential local and systemic responses in composition, quantity and time courses of emissions mirror the existence of several regulation processes triggered by different signaling compounds and elicitors. 相似文献
18.
Richard Troy McMullin Peter N. Duinker David H.S. Richardson Robert P. Cameron David C. Hamilton Steven G. Newmaster 《Forest Ecology and Management》2010
The relationships between the structural complexity of coniferous forests and the epiphytic lichen communities that inhabit them were examined in 51 conifer-dominated stands in southwestern Nova Scotia. One hundred and fifteen lichen species were studied in stands in the age range of 50–300 years. Environmental variables shaping the structural complexity of each forest stand were measured and their relationship with lichen species were assessed using a canonical correspondence analysis (CCA). The CCA revealed that the considerable variation in lichen community composition can be explained by several environmental variables associated with forest structure. The stand orientation on the first axis of the CCA found the most important variables for lichen richness to be stand age, tree stem density and snag stem density. The stand orientation on the second axis is strongly correlated with deciduous stem density and abundance including specific deciduous tree species such as Acer rubrum abundance. The analysis indicates that the greater the structural complexity in the forest, and thus the more microhabitats available, the greater the lichen species richness. These results should provide forest managers with a better understanding of the environmental variables that influence lichen diversity, and contribute to the development of more sustainable forest management strategies. 相似文献
19.
通过乙醚、二氯甲烷和乙酸乙酯3种有机溶剂对竹醋液抽提,利用气相色谱-质谱联用仪（GC-MS法）对抽提物的化学组分及其相对含量进行分析。结果表明：1）3种有机溶剂抽提后的竹醋液组分种类及含量存在着差异,采用乙醚抽提得到27种化合物,二氯甲烷抽提得到44种化合物,乙酸乙酯抽提得到58种化合物,化合物类型主要包括有机酸类、酚类、酮类、醇类、酯类、醛类及少量其他物质。2）选用乙酸乙酯抽提可以得到更多种类的酸类、酚类、酮类和醛类物质;选用二氯甲烷抽提则能获得相对成分含量更高的酸类和酚类物质;而乙醚更适于抽提醇类物质。 相似文献