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1.
新疆鼠尾草的化学成分研究   总被引:19,自引:2,他引:17  
从新疆鼠尾草(Salvia deserta Schang0根中分离得到8个单体成分,根据化学和光谱方法鉴定为:正三十三烷(Tritriacontane)[Ⅰ]、6,7-去氢罗列酮(6,7-SDehydroroyleanone)[Ⅱ],7,β-羟基罗列酮(Taxochinon)[Ⅲ]、二十六烷酸(Hexaconsanoic acid)[Ⅳ]、3-乙酰剂墩果酸(3-Acetoxy-oleanolic acid)[Ⅴ]、β-谷甾醇(β-Sitosterol)[Ⅵ]、熊果酸(Ursolic acid)[Ⅶ],D-甘露醇(Mannitolum)[Ⅷ]。  相似文献   

2.
广藿香根与根茎挥发油成分研究   总被引:7,自引:0,他引:7  
应用气相色谱-质谱联用技术对广藿香根和根茎中挥发油成分进行了分析,从根油中分离出50个色谱峰,鉴定了47个化合物,占总量的95.02%,主要含广藿香酮(81.71%)、d-苦橙油醇(2.88%)、十六烷酸(2.21%)、广藿香醇(1.98%)和3,7,11-三甲基-2,6,10-十二烷三烯-2-醇乙酸酯(1.09%)、广藿香醇(1.98%)和3,7,11-三甲基-2,6,10-十二烷三烯-1-醇乙  相似文献   

3.
云南山楂果化学成分的研究   总被引:9,自引:0,他引:9  
从云南山楂的果实中分得10个化物,经光谱分析及化学反应分别鉴定为槲皮素(Ⅰ)、芦丁(Ⅱ)、牡荆素(Ⅲ)、金丝挑甙(Ⅳ)、胡萝卜甙(Ⅴ)、熊果酸(Ⅵ)、氯原酸(Ⅶ)、奎宁酸(Ⅷ)、β-谷甾醇(Ⅺ)及二十九烷醇(Ⅹ)。  相似文献   

4.
乌桕化学成分的研究(Ⅰ)   总被引:2,自引:0,他引:2  
从乌柏「sapium sebiferum(L.)Roxb.」叶虫分离出四个化合物,经波谱鉴定分别是:β-谷甾醇、正三十二烷醇、软木酮、N-苯基-1-萘胺。从乌桕茎皮中分离出两个化合物,经波谱鉴定分别是:莫雷亭酮、莫雷亭醇。其中正三十二烷醇,N-苯基-1-萘胺系首次从该植物中分离。  相似文献   

5.
倒心盾翅藤的化学成分研究   总被引:4,自引:0,他引:4  
从药用植物倒心盾翅藤(Aspidopterys obcordata Hemsl.)中首次分离得到5个化合物,通过波谱分析分别鉴定为木栓酮(1)、无羁萜-3β-醇(2)、二二烷酸甲酯(3)、10-二九烷醇(4)、豆甾醇(5)和daphnetin-8-glucopyranoside(6)。  相似文献   

6.
臭灵丹中四个新的倍半萜酸   总被引:6,自引:0,他引:6  
从云南省芒市产臭灵丹[Laggerapterodnta(DC.)Benth]中,分离得以4个新的桉烷型倍半萜酸,结构鉴定为5,12-二烯-桉烷-13-酸(1);1β-式-5,12-二烯-桉烷-13-酸(2);3β-羟基-5,12-二烯-桉烷-13-酸(3)。  相似文献   

7.
云南茯苓皮的化学成分研究   总被引:2,自引:0,他引:2  
从云南产茯苓表皮中分得6个三萜类化合物,经光谱数据鉴定为:茯苓酸(Ⅰ),3β-羟基羊毛甾烷-7,9(11),24-三烯-21-酸(Ⅱ),茯苓酸A(Ⅲ),茯苓酸B(Ⅳ),去氢齿孔酸(Ⅴ),齐果酸(Ⅵ  相似文献   

8.
云南茯苓皮瓣化学成分研究   总被引:4,自引:0,他引:4  
李典鹏  杨崇仁 《广西植物》1998,18(3):267-270
从云南产茯苓表皮中分得6个三萜类化合物,经光谱数据鉴定为:茯苓酸(Ⅰ),3β-羟基羊毛甾烷-7,9(11),24-三烯-21-酸(Ⅱ)、茯苓酸A(Ⅲ),茯苓酸B(Ⅳ)、去氢齿孔酸(Ⅴ),齐敦果酸(Ⅵ)。  相似文献   

9.
山木通的化学成分研究   总被引:1,自引:0,他引:1  
目的:对毛茛科铁线莲属植物山木通的化学成分进行提取、分离和鉴定。方法:用不同浓度乙醇提取,利用硅胶、SephadexLH-20、ODS柱色谱法对山木通的化学成分进行分离,根据理化性质和MS、NMR光谱数据进行结构鉴定。结果:经鉴定得到7个化合物,分别为β-谷甾醇(Ⅰ);正二十二烷(Ⅱ);3-羰基齐墩果烷(Ⅲ);正十六烷酸(Ⅳ);正二十六烷酸(Ⅴ);丁香酸(Ⅵ);5-羟基4-氧代戊酸(Ⅶ)。结论:所得化合物均为首次从该种植物中得到。  相似文献   

10.
运用硅胶、sephadex LH-20等柱色谱,从木蹄层孔菌子实体的乙醇提取物分离得到12个化合物,通过单体的理化性质、NMR和MS技术鉴定单体的结构为3-十六碳酸酯-7,22-二烯麦角甾醇(1),十八烷酸(2),棕榈酸(3),7,22-二烯麦角甾-3-酮(4),麦角甾-7,22-二烯-3-醇(5),5,8-过氧麦角甾-6,22-二烯-3-醇(6),3,3-二甲氧基-7,22-二烯麦角烷(7),28-乙酰白桦脂醇(8),白桦脂醇(9),β-羟基十八烷酸(10),9,10-二羟基十八烷酸(11),瑞香素(12)。采用Alamar Blue法检测单体化合物对人肺癌细胞NCI-H 460和人胃癌细胞SGC-7901的抑制活性。结果表明,化合物4对NCI-H 460细胞株的抑制活性最高,化合物9对SGC-7901的抑制活性最高。  相似文献   

11.
尹亮  李绍蓉  周敏  王乾  吴彦  罗鹏 《植物研究》2010,30(6):737-741
在四川西北部松潘县卡卡沟对青藏高原东缘高海拔地区3个不同放牧强度下的窄叶鲜卑花灌丛的空间结构进行了研究,结果表明:放牧干扰对卡卡沟东南坡的窄叶鲜卑花空间结构影响显著,植株的总生物量、总叶面积和茎的边材面积在重度放牧下显著低于轻度和中度放牧梯度样地。中度和重度放牧情况下叶片长度、宽度以及面积均比轻度放牧显著提高;植株高度随放牧强度增加出现先升后降的现象,而顶部枝叶生物量分配则出现与之相反的情况。虽然植物空间结构发生变化,但是单位边材面积上支持的叶面积并没有变化,中度放牧使植株枝叶生物量更加均匀分布。放牧干扰下植物空间结构的塑性变化依然受到Huber数的制约,使叶片蒸腾耗水与茎的供水能力上维持平衡。  相似文献   

12.
The genetic structure of Croatian Sibirea (Sibiraea croatica), a rare and endemic tertiary relic of Croatian and Herzegovinian flora, and its relationship with sibirea from Southern Russia and Southern Siberia (Sibiraea altaiensis) was studied using amplification, restriction and sequencing of the ITS region in genomic DNA and cpDNA and their comparisons with sequences of the Rosaceae species obtained from GenBank. The restriction analysis and separation in agarose gel showed no differences in length of the digested cpDNA between or within populations. Sequencing showed only minor variability between populations. Only a minor difference of 6 bp duplication in DNA amplified with ccmp 10-R and trnM primer pair was noticed in two geographically distinct populations. No differences in the restriction pattern for the ITS region in genomic rDNA indicates that all samples of sibirea belong to the same species since the ITS region was proven to be conserved within one taxonomic species. The minor differences that were␣obtained support the hypothesis that sibirea is an old tertiary relic that shows a minor variability, confirming previous preliminary results from comparisons of the Croatian and Altaic sibireas at the morphological level. Our data suggests that Croatian sibirea from the Balkan is a disjunct population identical to the Altaic species. Due to its disjunct occurrence in Southeastern Europe, the endemic status in the Dinarics, a relic that survived the glaciations, it deserves active conservation approaches through support of traditional use of high-mountain pastures for reducing natural reforestation of sibirea ancient sites.  相似文献   

13.
2010年1-5月在川西高原采用人工雪厚度梯度试验(0、30和100 cm),应用网袋分解法对窄叶鲜卑花叶片凋落物进行分解试验,测定了凋落物的分解速率及其养分动态.结果表明:在无雪被覆盖的样地上分解5个月后的凋落物质量损失率为29.9%,而中雪和深雪样地的凋落物质量损失率分别为33.8%和35.2%.分解过程中,凋落物氮存在一定的富集现象,磷处于波动的富集状态,碳质量分数和碳氮比均呈现前期急剧下降后期逐渐上升的趋势.雪被覆盖显著增加了凋落物的质量损失率和氮含量,而对碳和磷含量无显著影响.在川西高原地区,30 cm以上的持续雪被覆盖能够改变凋落物的分解过程,从而可能对土壤营养物质转化和植物群落构建产生实质性的影响.  相似文献   

14.
Sibiraea angustata (Rehd.) Hand.-Mazz. scrub is a kind of typical and representative community on the eastern Qinghai-Tibetan Plateau, and is distributed on the subalpine and alpine belts in northwestern Sichuan with the latitude between 31~ and 34~ 47 quadrats were surveyed in the representative distributionarea of Sibiraea angustata scrub in order to probe into its types, characteristics, relationship with environmental factors and biomass structure. Combined with the quantitative classification, the result showed that Sibiraea angustata formation in the northwestern Sichuan could be divided into 4 association groups and 10 association types. Furthermore, the analysis of PCA (principal component analysis) ordination determined that the distribution of the plant communities was closely related to the moisture and organic matter content in the soil and the vertical change of heat. Meanwhile, the lowest classification unit of the community-association was most susceptible to the variation of environmental factors. The research of biomass expressed that the total biomass of the Sibiraea angustata community fluctuated between 38.99 t·hm- 2 and 47.72 t·hm-2, among which the biomass of the shrub layer and herb layer were 25.87- 32.16 t·hm-2 and 12.05 - 13.73 t·hm-2 respectively. Generally speaking, it could be concluded that on the high altitude area the biomass of the aboveground was more than that of the underground, such as the underground biomass of Sibiraea angustata community was 19.04% –42.72% more than that of the aboveground.  相似文献   

15.
应用PCR产物直接测序法分析了窄叶鲜卑花居群间nrDNA(核糖体DNA)ITS序列和cpDNA(叶绿体DNA)trnL-F的碱基差异,并与cpDNAtrnS-G序列和rpl20-rps12序列进行比较,从而初步研究两套植物基因组的变异速率。采用改良的CTAB法从硅胶干燥的窄叶鲜卑花叶片中提取总DNA,并对nrDNA ITS和cpDNAtrnL-F区域进行扩增、纯化、测序。nrDNA ITS序列共有601 bp,有变异位点3处,变异位点百分率为0.05%,(G+C)含量为41.4%。cpDNAtrnL-F序列共有927 bp,有变异位点1处,变异位点百分率0.01%,(G+C)含量为32.6%,两种序列的核苷酸多样性非常低。比较发现,窄叶鲜卑花nrDNA ITS区域较cpDNAtrnS-G序列和rpl20-rps12序列保守,变异速率较慢,比cpDNAtrnL-F序列变异速率稍快。通过对ITS序列单倍型(haplotype)进行分析发现,窄叶鲜卑花现有分布范围经历了居群近期范围扩张,与叶绿体基因组(trnS-G和rpl20-rps12序列)得出的结论一致。因此,窄叶鲜卑花nrDNA ITS序列适合该种的谱系地理学研究。  相似文献   

16.
窄叶鲜卑花(Sibiraeaangustata(Rehd.)Hand.Maz.)灌丛是青藏高原东缘高山灌丛中特有的、具代表性的类型。选择该群落的典型分布区域,运用数值分类法,将窄叶鲜卑花群系分为4个群丛组、10个群丛类型。用PCA排序技术定量分析了各类型在空间地理上的分布格局,以及与环境因子之间的关系。结果表明:各类型的分布主要取决于环境中土壤条件(主要是土壤水分和土壤有机质含量)和热量条件的垂直梯度变化,而群落的分类等级越低,对环境因子的变化越敏感。生物量的研究表明,窄叶鲜卑花灌丛的群落生物量在38.99~47.72t·hm-2之间,其中灌木层和草本层的生物量分别在25.87~32.16t·hm-2和12.05~13.73t·hm-2之间,而地下部分的生物量通常高于地上部分。  相似文献   

17.
《植物生态学报》2017,41(6):610
Aims Understanding the responses of root exudative carbon (C) to increasing nitrogen deposition is important for predicting carbon cycling in terrestrial ecosystems. However, fewer studies have investigated the dynamics of root exudation in shrubbery ecosystems compared to forests and grassland ecosystems. This objective of this study was to determine the effects of nitrogen fertilization on the rate and C flux of root exudates.Methods Three levels of nitrogen addition treatments were applied to a Sibiraea angustata shrubbery ecosystem situated at the eastern fringe of Qinghai-Xizang Plateau, including N0 (without nitrogen application), N5 (nitrogen addition rate of 5 g·m-2·a-1), and N10 (nitrogen addition rate of 10 g·m-2·a-1), respectively, in 5 m ´ 5 m plots. Root exudates were collected in June, August and October of 2015, using a modified culture-based cuvette system. Root biomass in each plot was measured with root core method.Important findings The rates of root exudates on biomass, length, and surface area basis all displayed apparent seasonal variations during the experimental period, with the magnitude ranked in the order of: August > June > October, consistent with changes in soil temperature at 5 cm depth. With increases in the nitrogen addition rate, the rate of root exudates on biomass, length, and area basis all trended lower. Compared with the control (N0), the N5 and N10 treatments significantly reduced fine root biomass in the Sibiraea angustata shrubbery, by 23.36% and 33.84%, respectively. The decreasing root exudation and fine root biomass in response to nitrogen addition significantly decreased C flux of root exudates. Our results provide additional evidences toward a robust theoretical foundation for better understanding soil C-nutrient cycling process mediated by root exudation inputs in Alpine shrubbery ecosystems under various environmental changes.  相似文献   

18.
《植物生态学报》2017,41(1):126
Aims Little is known about the stoichiometric characteristics of carbon (C), nitrogen (N) and phosphorus (P) in plateau shrubs across China. Sibiraea angustata is a typical and representative shrub species on the eastern Qinghai- Xizang Plateau, and exploring its C, N and P distribution patterns and stoichiometric properties in different organs (including root, shoot, leaf, twig and fruit) would help us better understand the mechanisms of C, N and P cycling and balance in the S. angustata dominated shrub ecosystem.
Methods Sixteen sampling sites were selected on the eastern Qinghai-Xizang Plateau by the stratified sampling method. The height and coverage of the dominant shrubs, latitude, longitude and altitude of the sites were recorded. Three 5 m × 5 m plots were selected at each site. At least 128 biological samples of plant organs of S. angustata were collected and measured, respectively. The C and N concentrations of plant samples were analyzed using an elemental analyzer (2400 II CHNS). The P concentration was analyzed using the molydate/ascorbic acid method after H2SO4-H2O2 digestion.
Important findings The C, N and P concentrations of different organs followed the order of: shoot (495.07 g·kg-1) > twig (483.37 g·kg-1) > fruit (480.35 g·kg-1) > root (468.47 g·kg-1) > leaf (466.33 g·kg-1); leaf (22.27 g·kg-1) > fruit (19.74 g·kg-1) > twig (7.98 g·kg-1) > shoot (4.54 g·kg-1) > root (4.00 g·kg-1) and fruit (2.85 g·kg-1) > leaf (1.92 g·kg-1) > twig (0.96 g·kg-1) > root (0.52 g·kg-1) > shoot (0.45 g·kg-1), respectively. The ranges of the coefficient of variation (CV) for C, N and P concentrations were 1.71%-4.44%, 14.49%-25.50% and 11.46%-46.15%, respectively. Specifically, the C concentration was relatively high and stable, and the maximum CV values for N and P were found in roots. The N:P value of different organs varied from 7.12-12.41 and the minimum CV for N:P was found in twig, which indicated that N:P in twig had higher internal stability. In addition, correlation analysis indicated that the C concentration was significantly negatively correlated with N and P concentrations and correlation coefficients were -0.407 and -0.342, respectively. However, N concentration had dramatically positive correlation with P concentration and the correlation coefficient was 0.814. These results also could indicate that the C, N and P stoichiometric characteristics in the S. angustata shrub accorded with the homeostatic mechanism and growth rate hypothesis to some extent, the distributions of C, N and P concentrations were closely related to the function of the organs and it should be prudent to use ecological stoichiometric ratios to judge the condition of nutrient limitation at the species level.  相似文献   

19.
房福金  肖金兰  王东 《生态学报》2023,43(7):2927-2937
氮(N)是陆地生态系统初级生产力的重要限制因子,大气N沉降的增加将会对植物的化学元素含量和生物量产生重要影响,进而影响凋落物的化学计量特征及其养分归还。高寒灌丛是陆地生态系统的重要组成部分,但有关N沉降对高寒灌丛凋落物尤其是凋落枝的化学元素和生物量的研究还较为缺乏,难以深入揭示N沉降对高寒灌丛土壤碳(C)和养分循环的影响机理。基于此,以青藏高原东部地区的优势高寒灌丛类型—窄叶鲜卑花(Sibiraea angustata(Rehd.) Hand.-Mazz.)灌丛为研究对象,连续4年人工模拟N沉降,分析了凋落枝C、N、磷(P)、木质素和纤维素化学计量特征及其归还量对不同N添加浓度(0、20、50、100 kg hm-2 a-1)的响应趋势。结果表明:(1)N添加对凋落枝C、N含量无显著性影响(P>0.05),而对P、木质素和纤维素含量有显著性影响(P<0.05),但不同年份间的影响趋势不一致;(2)4年的N添加并未改变凋落枝的C/N、N/P,但显著降低了凋落枝的木质素/N(第3年)、C/P(第1年和第4年)和C/N/P(第1年);(...  相似文献   

20.
李娇  尹春英  周晓波  魏宇航  高巧  刘庆 《生态学报》2014,34(19):5558-5569
开展土壤呼吸对大气氮沉降增加的响应研究对预测陆地生态系统碳循环具有重要意义。采用外施氮肥模拟氮沉降,结合壕沟法分离土壤呼吸组分,研究青藏高原东缘主要的灌丛类型——窄叶鲜卑花(Sibiraea angustata)灌丛土壤呼吸对不同施氮水平(N0(对照)、N2、N5和N10分别相当于0、2、5和10 g N m-2a-1浓度的氮沉降)的短期响应。结果表明:试验期间(2012年5—10月份),(1)土壤呼吸呈现明显的季节变化,施氮对生长季土壤总呼吸、异养呼吸无显著影响,而对自养呼吸有显著的抑制作用(P0.05)。(2)土壤呼吸也存在显著的日变化,施氮对一天中土壤总呼吸及其组分均有显著影响(P0.001)。总体上,施氮促进了土壤总呼吸、异养呼吸,而抑制了自养呼吸。(3)施氮对土壤总呼吸、异养呼吸平均每月排放CO2通量无显著影响,而对自养呼吸平均每月排放CO2通量有显著的抑制作用(P0.05),并在不同月份对土壤呼吸及其组分的影响不同。(4)土壤总呼吸、异养呼吸与地下5 cm土壤温度之间具有较好的指数关系(P0.001),而与土壤含水量相关性较弱。关于土壤呼吸各组分对大气氮沉降响应差异的机理有待进一步研究。  相似文献   

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