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1.
欧洲红豆杉细胞培养的研究   总被引:3,自引:0,他引:3  
从欧洲红豆杉(Taxusbaccata)的嫩茎及什叶诱导出愈伤组织,并对之进行了愈伤组织培养及细胞悬浮培养研究;利用HPLC方法测定了培养物合成紫杉醇的能力.探索了提高培养细胞生长率及紫杉醇含量的一些措施.结果表明,欧洲红豆杉愈伤组织及悬浮培养细胞的生长速率已分别达到0.27g·L-1·d-1和0.35g·L-1·d-1,紫杉醇含量分别为0.0031%和0.017%。  相似文献   

2.
红豆杉培养细胞紫杉醇的分离及鉴定   总被引:2,自引:0,他引:2  
红豆杉培养细胞紫杉醇的分离及鉴定甘烦远,郑光植,彭丽萍,沈月毛(中国科学院昆明植物研究所昆明650204)关键词红豆杉;紫杉醇;细胞培养;分离鉴定ISOLATIONANDIDENTIFICATIONOFTAXOLFROMCULTUREDCELLSOF...  相似文献   

3.
Ecology of Pacific Yew (Taxus brevifolia) in Western Oregon and Washington   总被引:2,自引:0,他引:2  
Taxus brevifolia , a subcanopy tree or shrub in forests of the Pacific Northwest, has been harvested intensively in recent years. With management concerns as an impetus, we examined the distribution and population dynamics of Taxus based on data from the mountains of western Oregon and Washington. Surveys of natural forests, long-term studies of forest recovery following logging, and census data on marked trees in forest stands support the hypothesis that Taxus is a widespread but predominantly late-successional species. Sensitive to fire and slow to recover from disturbance on many sites, Taxus attains maximal basal area and adult stem density in old forests. Colonization of Taxus is often slow in potentially suitable habitats. Conservation of Taxus at the landscape level may require large, unmanaged reserves and maintenance of patches of old forest within managed forests. Long rotations (centuries) between harvest events will enhance the long-term viability of the species. Practices designed to accelerate the development of old-growth forest structure will not benefit Taxus and other species requiring long disturbance-free intervals for recovery.  相似文献   

4.
Sre Ambel is the most productive coastal area for marine fisheries in Cambodia. This paper explores the management concept of extractive reserve instruments to find the most effective application in the coastal areas of Cambodia. Since there are various extractive models in the world, the most important objective is to determine which extractive reserve model is best suited to real practices where the ability of the fisheries’ residents to apply laws and guidelines vary from one place to another. To reflect these objectives, this paper looks at various examples around the world, especially from various Latin American countries. The level of local ability to apply laws and regulations is determined by the weight average index method. These results shows that fishers’ education levels are sufficient to apply laws and regulations, but their understanding of existing fisheries guidelines is still below average. Although the level to which they satisfy the guidelines is poor, local people are willing to establish new appropriate guidelines for future effective application. Therefore, local fishers have the ability to apply laws and regulations under new extractive reserve aspects. An extractive reserve policy combines all available instruments to manage the lagoon. The best alternative is to develop strong collaboration among the various stakeholders in the area. This converts an open-access to common property resource use regime. All instruments of extractive reserve were satisfied by the local fishers. However, extractive reserve seems to be similar with fish refuge concept which currently proposed by Southeast Asian Fisheries Development Centre (SEAFDEC).  相似文献   

5.
利用模拟酸雨实验对珍稀濒危植物曼地亚红豆杉和南方红豆杉生长及生理生化指标进行研究。结果表明,pH4.5的模拟酸雨促进了曼地亚红豆杉(Taxus media)和南方红豆杉(T.mairei)的株高生长(与对照相比分别促进了19%和72%),pH3.5的模拟酸雨对其有一定的影响,但不显著。pH4.5和pH3.5的酸雨处理下,曼地亚红豆杉基径比对照分别下降了46%和42%;南方红豆杉的相应值分别是34%和43%。总的来说,模拟酸雨促进了这两种红豆杉叶绿素的质量分数,类胡萝卜素的质量分数变化因种而异。酸雨处理提高了曼地亚红豆杉抗氧化系统酶活性,与对照相比约提高了5%~142%;南方红豆杉的相应值为-16%~35%。曼地亚红豆杉游离脯铵酸和丙二醛(MDA)的质量分数比对照提高了13%~73%;而南方红豆杉的相应质量分数基本等于或低于对照。与南方红豆杉相比,曼地亚红豆杉对酸雨更加敏感。  相似文献   

6.
红豆杉细胞抗病反应的诱导及其与紫杉醇合成的关系   总被引:3,自引:0,他引:3  
采用从红豆杉植株不同部位(叶、内皮、根等)分离筛选获得的各种真菌制备的激发子,对6种不同红豆杉细胞株进行诱导作用研究。结果表明,不同细胞对不同真菌制备的激发子的抗病反应有显著的区别,并建立3种-具菌互作模式:极不相容(细胞抗性强,受损小),不相容(抗性强,受损也较严重),相容(细胞抗性小,受损严重)。结果还表明,极不相容和不相容互作模式中细胞的紫杉醇产量显著高于CK,而相容互作模式的细胞不合有紫杉, 同一真菌由不同的方法制备成的不同分子量大小或不同成分的激发子,对细胞的抗病反应与紫杉醇合成的影响不同,这些结果为诱导作用机理及调控红豆杉细胞合成紫杉醇的研究具有指导意义。  相似文献   

7.
Ethyl carbamate in foods and beverages: a review   总被引:7,自引:0,他引:7  
Food and beverages contain many toxic chemicals that raise health concerns. Ethyl carbamate (EC) or urethane is the ethyl ester of carbamic acid. It occurs at low level, from ng/L to mg/L, in many fermented foods and beverages. Ethyl carbamate is genotoxic and carcinogenic for a number of species such as mice, rats, hamsters and monkeys. It has been classified as a group 2A carcinogen, “probably carcinogenic to humans”, by the World Health Organization’s International Agency for Research on Cancer (IARC) in 2007. The benchmark dose lower limit of ethyl carbamate is 0.3 mg/kg bw per day and the mean intake of ethyl carbamate from food is approximately 15 ng/kg bw per day. Those levels were calculated for relevant foods including bread, fermented milk products and soy sauce. Alcoholic beverages were not included in this calculation. However, high levels of ethyl carbamate can be found in distillated spirits at concentrations ranging from 0.01 to 12 mg/L depending on to the origin of spirit. Alcoholic drinks should thus be considered as a source of ethyl carbamate. Ethyl carbamate is produced by several chemical mechanisms: first, from urea and various proteins like citrulline produced during the fermentation step and second from cyanide, and hydrocyanic acid, via ethyl carbamate precursors such as cyanate. A large panel of ethyl carbamate formation mechanisms is described from simple ethanolysis of urea in homogeneous liquid phase to photochemical oxidation of cyanide ion or complex heterogeneous gas/solid catalytic reactions. Determination of ethyl carbamate in foods and beverages involves various strategies according to the material, food or beverage, solid or liquid, and according to the concentration, from ng/L to mg/L. Usually, adapted extractive techniques and pre-concentration step are followed by analysis by gas chromatography coupled to mass spectrometry (GC–MS of GC–MS–MS). High performance liquid chromatography (HPLC) and semi-quantitative spectroscopic methods (infra-red) are also proposed as valuable alternatives to the classical but time-consuming GC–MS. Various preventing methods are developed and used in some cases at industrial scale to lower ethyl carbamate levels in food. Two types of preventing methods are described. First, adapted and optimised practices in all step of the chain of foods’ (or beverages) production lead in general to low ethyl carbamate level. Second, the abatement of ethyl carbamate precursors can be done by adapted enzymatic, physical chemical or chemical methods according to the natures of raw materials and conditions of their production processes.  相似文献   

8.
东北红豆杉植物地理学研究   总被引:12,自引:0,他引:12  
总结了东北红豆杉的地理分布概况和分布区特点,绘制了分布图,以在我国境内分布区域的主导气象因子构成指示指标组建立了东北红豆杉自然地理分布模型,并通过实例证明了该模型的有效性。  相似文献   

9.
We compare existing nontimber forest product extraction systems in Petén, Guatemala, and West Kalimantan, Indonesia, to identify key ecological, socioeconomic, and political factors in the design and implementation of extractive reserves. Ecological parameters include the spatial and temporal availability of harvested products and the sustainability of harvesting practices from both a population and an ecosystem perspective. Socioeconomic and political factors include the presence or absence of well-defined resource tenure rights, physical and social infrastructure, markets, and alternative land uses. We conclude that although extractive reserves can play a significant role in preserving tropical forests as a part of a broader land-use spectrum, their effectiveness is highly dependent on prevailing local ecological, socioeconomic, and political conditions. Ultimately, extractive reserves should be regarded as one component of an overall approach to the problem of tropical deforestation.  相似文献   

10.
The paper gives the background to the current debate in the U.K. concerning the possible need to introduce a standardised and perhaps mandatory system of environmental impact analysis for developmental proposals. This is shown to be a subject of very considerable interest to those concerned with mineral extraction and its environmental effects. The paper considers some of those features of the extractive industries which are of particular importance when selecting an approach to environmental assessment. It discusses the appropriate content for such a study. Attention is given to the socio-economic factors which are almost inevitably associated with the extractive industries. The paper concludes with a plea for a more systematic assessment of the potential impact of both new and continued extraction of raw materials and fossil fuels and suggests that there should be more emphasis on environmental issues when national, regional and local policies and plans for the extractive industries are prepared.  相似文献   

11.
简在友  许桂芳  孟丽 《生态环境》2007,16(1):201-204
微量元素对植物的生长发育有着十分重要的意义。对太行山野生红豆杉(Taxus chinensis var.mairei)菌根菌菌丝在分别加有硫酸锌、钼酸铵以及硫酸亚铁的PDA培养基中的生长发育状况进行了试验研究。所得数据同PDA对照组进行比较分析后,结果表明:Mo元素对红豆杉菌根菌菌丝的生长发育有很好的促进作用;Fe元素明显地促进红豆杉菌根菌菌丝的生长发育;Zn元素在一定范围内对红豆杉菌根菌菌丝的生长发育有一定的抑制作用。实验结果揭示出红豆杉菌根菌生长发育的一些营养因素。  相似文献   

12.
Polyphenols were located in all the layers of the periostracum and in inclusion bodies in the inner face of the outer-fold cells of Mytilus edulis L. Results, after 4 days periostracum repair, show that the proto-ostracal material is deposited in distinct layers. Inclusion bodies in the cells of the inner face of the outer fold appear to give rise to the polyphenols in the proto-ostracal material.  相似文献   

13.
This article follows papers by Pindyck and Heal and Barrow in applying a Hotelling-type depletion model to a particular resource industry: in this case that of nickel. By means of the model the resource rent per ton of nickel is calculated as the proper index of extractive resource scarcity. The time path of this resource rent indicates that the model explains industry behavior well and that, as in the two previous studies, depletion has been an important determinant of prices and rents in this industry.  相似文献   

14.
Abstract:  Although land preservation and promotion of successful regeneration are important conservation actions, their ability to increase population growth rates of slow-growing, long-lived trees is limited. We investigated the demography of Taxus floridana Nutt., a rare understory conifer, in three populations in different ravine forests spanning its entire geographic range along the Apalachicola River Bluffs in northern Florida (U.S.A.). We examined spatial and temporal patterns in demographic parameters and projected population growth rates by using four years of data on the recruitment and survival of seedlings and established stems, and on diameter growth from cross-sections of dead stems. All populations experienced a roughly 10-fold increase in seedling recruitment in 1996 compared with other years. The fates of seedlings and stems between 8 and 16 mm differed among populations. The fates of stems in two other size classes (the 2- to 4-mm class and the 4- to 8-mm class) differed among both populations and years. Individual stems in all populations exhibited similarly slow growth rates. Stochastic matrix models projected declines in all populations. Stochastic matrix analysis revealed the high elasticity of a measure of stochastic population growth rate to perturbations in the stasis of large reproductive stems for all populations. Additional analyses also indicated that occasional episodes of high recruitment do not greatly affect population growth rates. Conservation efforts directed at long-lived, slow-growing rare plants like Taxus floridana should both protect established reproductive individuals and further enhance survival of individuals in other life-history stages, such as juveniles, that often do not appear to contribute greatly to population growth rates.  相似文献   

15.
Whither Conservation Ethics?   总被引:1,自引:0,他引:1  
Abstract: A review of the moral foundations of American conservation provides a historical perspective for formulating a twenty-first century conservation ethic. Building on the Work of R.W. Emerson and H.D. Thoreau, John Muir formulated a Romantic-Transcendental Preservation Ethic that pitted the allegedly higher aesthetic and spiritual uses of nature against consumptive and extractive material uses. Gifford Pinchot formulated a more pedestrian and egalitarian Resource Conservation Ethic consistent with utilitarian and democratic ideals. Muir also adumbrated a more radical nonanthropocentric preservation ethic rhetorically cast in Biblical terms Aldo Leopold articulated a similarly nonanthropocentric environmental ethic in evolutionary and ecological terms. A review of Leopold's large literay estate, however, reveals that he continued to advocate active management for a mutually beneficial human-nature symbiosis, in addition to the passive preservation of "wilderness" As the human population grows and more nations develop, the best hope for conservation biology lies in a generalization of Leopold's ideal of ecosystems which are at once economically productive and ecologically healthy. The principal intellectual challenge raised by such an ideal for conservation biology is the development of criteria of ecological health and integrity in an inherently dynamic, evolving, and human-saturated biota.  相似文献   

16.
CERES is a forest stand growth model which incorporates sugar transport in order to predict both short-term effects and long-term accumulation of trace contaminants and/or nutrients when coupled with the soil chemistry model (SCHEM), and models of solute uptake (DIFMAS and DRYADS) of the Unified Transport Model, UTM. An important feature of CERES is its ability to interface with the soil-plant-atmosphere water model (PROSPER) as a means of both predicting and studying the effects of plant water status on growth and solute transport.CERES considers the biomass dynamics of plants, standing dead and litter with plants divided into leaves, stems, roots, and fruits. The plant parts are divided further into sugar substrate, storage, and in the case of stems and roots, heartwood components.Each ecosystem component is described by a mass balance equation written as a first-order ordinary differential equation.  相似文献   

17.
周黎明  顾惠芬 《环境化学》1995,14(5):449-453
本文对水样中的塔崩及其降解产物磷酸乙酯的提取方法进行了研究,试验了不同的萃取剂及萃取时溶液的pH值,优化了萃取条件,在pH=9时,二氧甲烷萃取塔崩的回收率较高,三次测定的变异系数小于3.0%,用气相色谱-质谱(EI方式)法测定了水样中的塔崩和磷酸乙酯。  相似文献   

18.
金银花三色软糖的制作   总被引:1,自引:0,他引:1  
为改变三色软糖的口味和功能,在传统三色软糖中加入金银花浸提液,制成口感独特,风味诱人,外表光滑美观的制品,对传统三色软糖的开发利用具有积极意义。  相似文献   

19.
林岚  李靖 《生态环境》2011,(10):1411-1417
采用选择性分离方法对药用植物红豆杉Taxus chinensis嫩枝和叶进行内生菌分离,得到一株放线菌En-1,经鉴定为链霉菌Streptomyces sp.;并对该菌进行液体培养条件优化、次生代谢物初筛及其抗菌活性的研究。通过添加宿主植物浸出物至En-1液体培养中以考察宿主对后者生长的影响,结果表明红豆杉叶浸出物能促进En-1的体外生长;而且En-1次生代谢物对5株供试菌中的黑曲霉具有抑制活性。通过En-1菌培养基优化并联合波谱法检测其发酵产物,显示8#配方(淀粉25 g.L-1,KNO3 1 g.L-1,K2HPO4.3H2O 0.5 g.L-1,NaCl 0.5 g.L-1,FeSO4.7H2O 0.01 g.L-1,MgSO4.7H2O 0.5 g.L-1)培养液中,En-1所产的次生代谢物最具结构多样性;同时8#配方也有利于该菌产生抗菌活性产物。本研究提示红豆杉内生放线菌可作为寻求药物先导化合物的资源菌。  相似文献   

20.
本研究以锌镀层退底废液中锌配备顺收为例探讨从盐酸体系中分离酸-金属的工艺特点,选取了高效又价廉的国产萃取剂(N-235)和反萃剂(生石灰),建立了新的回收处理工艺路线,中试结果证明此工艺在技术上和设备上是可行的。  相似文献   

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