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1.
五指毛桃黄酮和香豆素类成分研究   总被引:6,自引:0,他引:6  
对五指毛桃的化学成分进行了研究.分离得到11个化合物,根据理化性质和波谱数据,分别鉴定为补骨脂素(Ⅰ)、伞形花内酯(Ⅱ)、 5,3',4'-三羟基-3,7-二甲氧基黄酮(Ⅲ)、 5,7,2',4'-四羟基黄酮(Ⅳ)、 5-羟基-3,7,4'-三甲氧基黄酮(Ⅴ)、山柰酚(Ⅵ)、紫云英苷(Ⅶ)、金合欢素 7-O-β-D-吡喃葡萄糖苷(Ⅷ)、木犀草素7-O-β-D-吡喃葡萄糖苷(Ⅸ)、柚皮素(Ⅹ)及胡萝卜苷(Ⅺ).经检索,化合物Ⅱ~Ⅹ为首次从该植物中分离得到,化合物Ⅲ、Ⅳ、Ⅴ、Ⅷ、Ⅸ为首次从该属植物中分离得到.  相似文献   

2.
毛花柱忍冬花蕾化学成分研究   总被引:7,自引:2,他引:5  
对毛花柱忍冬花蕾进行化学成分研究,从中分离鉴定了10个化合物:绿原酸(Ⅰ)、5-O-咖啡酰基-奎宁酸丁酯(Ⅱ)、5-O-咖啡酰基-奎宁酸甲酯(Ⅲ)、槲皮素(Ⅳ)、木犀草苷(Ⅴ)、芦丁(Ⅵ)、山奈酚-3-O-芸香糖苷(Ⅶ)、秦皮乙素(Ⅷ)、β-谷甾醇(Ⅸ)和胡萝卜苷(Ⅹ)。其中化合物Ⅶ为首次从该属植物中分离,化合物Ⅰ、Ⅱ、Ⅲ、Ⅴ、Ⅵ、Ⅷ、Ⅸ、Ⅹ均为首次从该植物中分离。  相似文献   

3.
对救必应根皮的化学成分进行了系统研究.从其中分离并鉴定了12个化合物,分别为铁冬青酸(Ⅰ)、坡模醇酸(Ⅱ)、具栖冬青苷(Ⅲ)、苦丁冬青苷H(Ⅳ)、3-O-α-L-吡喃阿拉伯糖-3β, 19α-二羟基齐墩果烷-12-烯-28-酸-28-O-β-D-吡喃葡萄糖酯(Ⅴ)、丁香脂素4′-O-β-D-吡喃葡萄糖苷(Ⅵ)、咖啡酸4-O-β-D-吡喃葡萄糖苷(Ⅶ)、香草酸4-O-β-D-吡喃葡萄糖苷(Ⅷ)、丁香苷(Ⅸ)、芥子醛葡萄糖苷(Ⅹ)、β-谷甾醇(Ⅺ)和胡萝卜苷(Ⅻ).其中,化合物Ⅱ、Ⅳ~Ⅷ为首次从该植物中分离得到.  相似文献   

4.
红花忍冬的黄酮类成分研究   总被引:2,自引:0,他引:2  
对红花忍冬(Lonicera syringanthaM axim.)干燥地上部分进行化学成分研究。分离鉴定了5个黄酮类化合物:木犀草素(Ⅰ)、木犀草素-7-O-β-D-葡萄糖苷(Ⅱ)、香叶木素(Ⅲ)、香叶木素-7-O-β-D-葡萄糖苷(Ⅳ)和柏黄酮(Ⅴ)。经文献检索,这5个化合物均为首次从该种植物中分离得到,其中化合物Ⅲ、Ⅳ、Ⅴ系首次从该属植物中分得。  相似文献   

5.
采用硅胶柱层析、凝胶柱层析等手段,对金花忍冬地上部分化学成分进行了分离纯化,并通过波谱解析和理化鉴定确定了它们的结构.共分离鉴定了7个化合物:其中3个黄酮类化合物:大波斯菊苷(Ⅰ)、五浅裂益母草素(Ⅱ)、槲皮素(Ⅲ);2个双黄酮类化合物:穗花杉双黄酮(Ⅳ)和喜柏双黄酮(Ⅴ);另外还分得绿原酸(Ⅵ)和胡萝卜苷(Ⅶ).7个化合物均为首次从该种植物中分离得到,其中化合物Ⅰ和Ⅱ系首次从该属植物中分得,并首次报道了化合物Ⅱ的1H NMR和13C NMR数据.  相似文献   

6.
对土耳其棓子的抑菌活性成分进行研究.采用硅胶柱色谱、SephadexLH-20凝胶柱色谱、制备薄层色谱、HPLC,对土耳其棓子中的化学成分进行分离,通过理化性质和光谱数据鉴定其结构,采用抑菌试验对土耳其棓子不同提取部位和单体化合物进行抑菌活性筛选.分离得到7个化合物,分别鉴定为:没食子酸(Ⅰ)、间-二没食子酸(Ⅱ)、对-二没食子酸(Ⅲ)、没食子酸甲酯(Ⅳ)、没食子酸乙酯(Ⅴ)、1,2,3,6-四-O-没食子酰基-β-D-葡萄糖(Ⅵ)和1,2,3,4,6-五-O-没食子酰基-β-D-葡萄糖(Ⅶ).土耳其棓子乙酸乙酯部位含主要抑菌活性成分,其中化合物Ⅲ和Ⅴ均为首次从该棓子中分离得到.  相似文献   

7.
青橄榄叶的化学成分研究   总被引:5,自引:0,他引:5  
对橄榄科橄榄属青橄榄树叶子的化学成分进行了研究。从乙酸乙酯萃取部位分得8个化合物。经理化及光谱方法鉴定分别为:没食子酸乙酯(Ⅰ)、东莨菪素(Ⅱ)、没食子酸(Ⅲ)、穗花杉双黄酮(Ⅳ)、肌醇(Ⅴ)、槲皮素(Ⅵ)、卢一谷甾醇(Ⅶ)、4,5-去氢诃子裂酸三乙酯(Ⅷ)。其中化合物Ⅷ为新化合物,化合物Ⅴ、Ⅵ为首次从该属植物中得到,化合物Ⅳ、Ⅶ为首次从该植物中得到。  相似文献   

8.
对天然橡胶胶清的化学成分进行了研究.运用硅胶柱色谱及葡聚糖凝胶LH-20柱色谱进行化学成分的分离和纯化,用理化方法及波谱手段解析其化学结构.从天然橡胶胶清中分离得到13个化合物,鉴定了其中12个化合物的结构,分别为:木栓酮(Ⅰ)、羽扇豆醇(Ⅱ)、β-谷甾醇(Ⅲ)、棕榈酸(Ⅳ)、硬脂酸(Ⅴ)、胡萝卜苷(Ⅵ)、尼古丁酸(Ⅶ)、琥珀酸(Ⅷ)、没食子酸(Ⅸ)、果糖(Ⅹ)、白坚木皮醇(Ⅺ)和6-hydroxy-cleistopholine (Ⅻ).经检索,其中化合物Ⅰ、Ⅱ、Ⅵ、Ⅶ、Ⅸ和Ⅻ为首次从天然橡胶胶清中分得.  相似文献   

9.
对土耳其掊子的抑菌活性成分进行研究。采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、制备薄层色谱、HPLC,对土耳其掊子中的化学成分进行分离,通过理化性质和光谱数据鉴定其结构,采用抑菌试验对土耳其槽子不同提取部位和单体化合物进行抑菌活性筛选。分离得到7个化合物,分别鉴定为:没食子酸(Ⅰ)、间-二没食子酸(Ⅱ)、对-二没食子酸(Ⅲ)、没食子酸甲酯(Ⅳ)、没食子酸乙酯(Ⅴ)、1,2,3,6-四-O-没食子酰基-β-D-葡萄糖(Ⅵ)和1,2,3,4,6-五-O-没食子酰基-β-D-葡萄糖(Ⅶ)。土耳其桔子乙酸乙酯部位含主要抑菌活性成分,其中化合物Ⅲ和Ⅴ均为首次从该桔子中分离得到。  相似文献   

10.
用各种柱色谱方法进行分离纯化,根据理化性质和波谱解析鉴定其化学结构,从而研究酸枣根中的化学成分。结果表明从酸枣分离得到7个化合物,分别鉴定为羽扇豆醇(Ⅰ),白桦酯酸(Ⅱ),美洲茶酸(Ⅲ),异美洲茶酸(Ⅳ),豆甾醇(Ⅴ),豆甾醇-3-O-葡萄糖苷(Ⅵ),蛇婆子碱(Ⅶ)。其中化合物Ⅳ、Ⅵ、Ⅶ为首次从该植物中得到。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

14.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

16.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > TithoniaEuphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

17.
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.  相似文献   

18.

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.  相似文献   

19.
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.  相似文献   

20.
Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.  相似文献   

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