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1.
HPLC法测定木豆中牡荆苷和异牡荆苷含量   总被引：3，自引：1，他引：2  
建立了测定木豆叶、茎、根中牡荆苷和异牡荆苷含量的高效液相色谱分析方法.色谱柱为HIQ Sil C18V(250 mm × 4.6 mm,5 μm);流动相为甲醇-水-甲酸(体积比35:64.74:0.26); 检测波长330 nm;流速1 mL/min;进样量10 μL; 柱温30 ℃.在2～200 mg/L 牡荆苷、异牡荆苷质量浓度与色谱峰面积线性关系良好; 牡荆苷峰面积精密度的相对标准偏差(RSD)最大为2.93 %,重复性RSD为2.91 %,加样回收率为97.38 %; 异牡荆苷峰面积精密度的RSD最大为2.69 %,重复性RSD为3.37 %,加样回收率为98.63 %.木豆叶、茎、根中牡荆苷、异牡荆苷的质量分数分别为0.768、 0.066、 0.183 mg/g 和0.799、 0.139、 0.013 mg/g.叶中牡荆苷和异牡荆苷含量明显高于茎、根中的含量,可以作为大规模获得牡荆苷、异牡荆苷的资源.  相似文献   

2.
以低共熔溶剂为提取溶剂，用球磨法从毛竹叶中提取黄酮碳苷类化合物，采用高效液相色谱-飞行时间质谱(LC-Q-TOF-MS)测定竹叶中4种黄酮碳苷(异荭草苷、荭草苷、异牡荆苷和牡荆苷)的含量，通过单因素试验和正交试验，对低共熔溶剂的含水量、提取时间、液料比等因素进行考察。结果表明，从竹叶中提取黄酮碳苷的最佳工艺为：低共熔溶剂(氯化胆碱和乙二醇构成)含水量50%、提取时间150 s、液料比6∶1(mL∶g)。在该条件下，从竹叶中提取4种黄酮碳苷的总提取得率为1.55 mg/g,其中，异荭草苷0.99 mg/g、荭草苷0.23 mg/g、牡荆苷0.04 mg/g、异牡荆苷0.29 mg/g。该方法提取得率比浸渍提取法提高了7.6%,且节约了时间和有机溶剂。利用该优化工艺，结合LC-Q-TOF-MS检测，成功应用于以毛竹叶为原料制成竹茶样品的黄酮碳苷提取与测定。  相似文献   

3.
为给刺玫果的开发利用提供参考依据。采用单因素试验与正交试验相结合的研究方法,以木犀草素、金丝桃苷的峰面积为指标,采用高效液相色谱法,建立了同时测定刺玫果中木犀草素、金丝桃苷含量的方法,探寻并优化了离子液体辅助提取刺玫果中木犀草素、金丝桃苷的工艺条件。检测与分析结果表明:色谱柱为伊利特ODS2 C18(4.6 mm×250 mm,5μm),流动相以乙腈-0.2%磷酸水溶液梯度洗脱,进样量20μL,检测波长360 nm,柱温35℃;木犀草素、金丝桃苷进样质量浓度在0.19~15.20μg·m L-1范围内其线性关系(r=0.997 7)均良好;木犀草素的平均回收率为97.49%,RSD为1.76%;金丝桃苷的平均回收率为101.07%,RSD为1.83%。优化试验结果表明,离子液体辅助提取的最佳工艺条件为:离子液体浓度为0.45 mol·L-1,料液比为1∶25,乙醇的体积分数为70%,提取温度为80℃,提取时间为90 min,超声波功率为180 W;在此优化的提取条件下,木犀草素、金丝桃苷的提取率分别为11.99、25.36μg·g-1,其提取率分别提高了36.87%、49.09%。验证试验结果表明:建立的含量测定方法具有良好的精密度,结果准确可靠;优化的提取方法快速、简单、提取率高。  相似文献   

4.
以勃氏甜龙竹竹叶为原料,对其中竹叶黄酮的超声提取工艺进行研究,同时采用高效液相色谱法(HPLC)对勃氏甜龙竹、箬竹、浦竹仔及椅子竹中总黄酮及牡荆苷、异牡荆苷、荭草苷、异荭草苷的含量进行测定。结果表明,勃氏甜龙竹超声提取最佳的工艺为:甲醇作为提取溶剂、浓度为70%、料液比为1︰10(w︰v)、超声时间60min、温度40℃。在最佳提取条件下,勃氏甜龙竹中总黄酮得率能达到4.63%。采用高效液相色谱-外标法测定4种丛生竹中总黄酮,含量分别为0.795 2%、1.166 9%、0.092 6%、0.897 2%。勃氏甜龙竹、箬竹和椅子竹中均含有牡荆苷、异牡荆苷、荭草苷及异荭草苷,浦竹仔中仅含有牡荆苷和异牡荆苷。分析方法的建立,为丛生竹化学资源的利用奠定基础。  相似文献   

5.
建立高效液相色谱法,同时测定10个不同产地凤尾草中5种黄酮类成分:新西兰牡荆苷、忍冬苷、野漆树苷、木犀草素和芹菜素的含量.使用Diamonsil C18色谱柱(4.6 mm×250 mm,5 μm),以乙腈-0.1％甲酸水溶液为流动相进行梯度洗脱(0～10 min,15∶85;20～30 min,25∶75;35～40 min,50∶ 50),流速1.0 mL/min,检测波长350 nm,柱温25℃.结果新西兰牡荆苷、忍冬苷、野漆树苷、木犀草素和芹菜素5个黄酮类化合物在测定的范围内峰面积与浓度之间均表现出良好的线性(r≥0.999,n=5),加样回收率分别为97.18％ ～ 105.20％(RSD为1.72％～3.20％)、95.02％～104.92％(RSD为1.96％～2.93％)、98.45％～ 103.70％(RSD为1.66％～2.70％)、96.41％ ～ 104.73％(RSD为1.03％～3.46％)、95.82％～99.34％(RSD为1.85％～ 3.95％).结果表明凤尾草中5种黄酮含量的地区差异性不大,各地区凤尾草中5种黄酮类化合物总含量在0.5 ～2.2 mg/g范围内.  相似文献   

6.
建立了HPLC同时检测竹叶中4种黄酮碳苷(异荭草苷、荭草苷、牡荆苷和异牡荆苷)的方法,并测定了这4种常见的黄酮碳苷在24种刚竹属竹叶的含量,以及早园竹4个季度中黄酮碳苷的含量。采用Inertsil ODS-3色谱柱(250 mm×4.6 mm,5μm),以乙腈/0.5%磷酸水溶液(体积比15∶85)为流动相进行等度洗脱,流速为1.0 mL/min,柱温为30℃,检测波长340 nm。实验结果表明:4种黄酮碳苷的质量浓度在1～300 mg/L范围内与峰面积呈良好的线性关系,相关系数均在99%以上,加标回收率(n=3)分别为97.14%、100.53%、93.60%和95.66%,RSD值分别为1.11%、1.45%、1.96%和1.43%;24种刚竹属竹叶中黄酮碳苷含量差异显著,4种黄酮碳苷质量分数的总和在286.14～3 838.79 mg/kg之间,毛金竹最高,为3 838.79 mg/kg;早园竹中4种黄酮碳苷的含量随时间变化差异明显,质量分数的总和在1 371.15～4 367.01 mg/kg之间,其中1月份采摘时总质量分数最高,为4 367.01 mg/kg。HPLC法准确度高,适用于竹叶黄酮碳苷的测定。  相似文献   

7.
为探索簕竹属主要竹种竹叶提取物中黄酮类成分的开发利用,以簕竹属10个竹种的竹叶为原料,提取、分离和纯化后得到竹叶提取物,建立了测定竹叶提取物中5种黄酮类成分的HPLC方法,采用DPPH法和ABTS法对竹叶提取物的抗氧化活性进行评价。竹叶中5种黄酮类成分异荭草苷、荭草苷、牡荆苷、异牡荆苷和木犀草苷的HPLC方法为：采用YMC-Pack ODS-A色谱柱(250 mm×4.6 mm, 5μm),以0.5%乙酸/水溶液(A)和乙腈(B)为流动相,14%B等梯度洗脱40 min,进样量10μL,流速1 mL/min,柱温30℃,检测波长340 nm。此条件下,5种黄酮类成分在40 min内实现完全分离,分离度均大于1.2,其质量浓度与峰面积具有良好的线性相关性,相关系数R2>0.999,加标回收率在94.36%～105.37%之间,相对标准偏差(RSD)在0.98%～3.48%之间,表明该方法稳定可靠。测得的10种簕竹属竹叶提取物中5种黄酮类成分的总量为62.30～223.24 mg/g,其中凤尾竹竹叶提取物中的质量分数最高,为223.24 mg/g。10种簕竹属竹...  相似文献   

8.
采用高效液相色谱法测定吉林地区3种乌头中乌头碱、新乌头碱和次乌头碱的含量。结果表明,新乌头碱在0.0016～2.0030g/L范围内线性关系良好,r为0.9996;平均加标回收率为98.6%,相对标准偏差(RSD)1.7%;乌头碱在0.0016～1.0005g/L范围内线性关系良好,r为0.9998;平均加标回收率为97.5%,RSD2.8%;次乌头碱在0.0016～1.0000g/L范围内线性关系良好,r为0.9995;平均加标回收率为96.7%,RSD1.9%。该方法简便易行,结果准确可靠,经对比分析得出,北乌头根中乌头碱(0.1926%)、新乌头碱(0.4658%)和次乌头碱(0.1045%)含量最高,可以作为今后驯化栽培的主要品种。  相似文献   

9.
该试验研究鹅毛竹叶酪氨酸酶抑制物的最佳提取工艺及其竹叶特征性成分的含量及活性。采用响应面法优化鹅毛竹叶酪氨酸酶抑制物的提取工艺,在此基础上利用分极法制备酪氨酸酶抑制活性部位(SAE),并采用HPLC法定量分析其中绿原酸、咖啡酸、异荭草苷、荭草苷、对香豆酸、牡荆苷、异牡荆苷、山奈酚和苜蓿素9个竹叶特征性成分;通过DPPH法、ABTS法、FRAP法和酪氨酸酶催化氧化左旋多巴速率法评价SAE及竹叶特征性成分的抗氧化和酪氨酸酶抑制能力。结果显示:鹅毛竹叶酪氨酸酶抑制物的最优工艺参数为乙醇浓度70%,料液比1∶16,提取温度80℃,提取时间1h。以此提取物为原料制备的SAE对酪氨酸酶的抑制IC50为658.46μg/m L,含有绿原酸(0.4285mg/g)、咖啡酸(0.0463mg/g)、异荭草苷(0.2999mg/g)、对香豆酸(0.4593mg/g)、山奈酚(1.7152mg/g)及苜蓿素(2.5513mg/g)6种竹叶特征性成分。其中咖啡酸的抑制酪氨酸酶活性最强,显著高于阳性对照熊果苷,推测为鹅毛竹叶抑制酪氨酸酶的主要活性成分之一。表明鹅毛竹叶是一种来源丰富的酪氨酸酶抑制原料,具有进一步研究和开发的意义。  相似文献   

10.
七叶莲总皂苷定量分析方法及其提取工艺研究   总被引：4，自引：2，他引：2  
以齐墩果酸为对照品,建立了比色法测定七叶莲总皂苷含量的方法;以总皂苷得率为指标,采用正交试验法对七叶莲总皂苷提取工艺进行了优化.结果表明:在比色法定量分析时,以5%香草醛冰醋酸溶液-高氯酸为显色剂,70℃加热15min显色后,选择546nm为测定波长,在40min内,测量结果稳定,总皂苷质量浓度在0.002~0.02g/L范围内呈良好的线性关系(r=0.99933);平均加样回收率为101.2%,相对标准偏差(RSD)为0.86%(n=6).在提取过程中,优化的工艺参数为:以50%(体积分数)乙醇为溶剂,控制固液比1∶15(g∶mL),80℃水浴提取2次,每次120min,此条件下总皂苷得率1.217%.  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.
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 > Tithonia ≥ Euphatorium > 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   

14.

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   

15.
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   

16.
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   

17.

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   

18.

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   

19.
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   

20.
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   

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