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1.
Bergamot (Citrus bergamia, Risso et Poiteau) essential oil (BEO) is a widely used plant extract showing anxiolytic, analgesic and neuroprotective effects in rodents; also, BEO activates multiple death pathways in cancer cells. Despite detailed knowledge of its chemical composition, the constituent/s responsible for these pharmacological activities remain largely unknown. Aim of the present study was to identify the components of BEO implicated in cell death. To this end, limonene, linalyl acetate, linalool, γ-terpinene, β-pinene and bergapten were individually tested in human SH-SY5Y neuroblastoma cultures at concentrations comparable with those found in cytotoxic dilutions of BEO. None of the tested compounds elicited cell death. However, significant cytotoxicity was observed when cells were cotreated with limonene and linalyl acetate whereas no other associations were effective. Only cotreatment, but not the single exposure to limonene and linalyl acetate, replicated distinctive morphological and biochemical changes induced by BEO, including caspase-3 activation, PARP cleavage, DNA fragmentation, cell shrinkage, cytoskeletal alterations, together with necrotic and apoptotic cell death. Collectively, our findings suggest a major role for a combined action of these monoterpenes in cancer cell death induced by BEO.  相似文献   

2.
Population viability risk management (PVRM) provides a framework for explicitly including qualitative information about the possible outcomes of a management decision with regard to the viability of an endangered population in conservation management. Multi-criteria decision-making (MCDM) techniques enables managers to select the most preferred choice of action in a context where several criteria apply simultaneously. In that context a combined approach of the PVRM concept and a MCDM technique is presented for the development, evaluation and finally ranking of the in situ conservation strategies. We discuss the concept based on a case study for the maintenance of a gene conservation forest of an English yew population (Taxus baccata L.) in Styria, Austria. As part of the PVRM the analytic hierarchy process (AHP) is used to evaluate six conservation strategies with regard to the viability of the yew population. The viability of the population is evaluated based on the results of an analysis of the current environmental, social and economical state and a characterization of the ecological parameters of its population. The most significant risk factors (illegal cutting, browsing by game, tree competition, light availability and genetic sustainability) are structured and prioritised according to their impact on the viability of the yew population applying the AHP. Effects of the six conservation strategies on the viability of the yew population are determined through a qualitative assessment of the probability of a decrease of the population along with four different environmental scenarios. In this context strategy IV combining selective thinning, protection measures, game control with public relation activities seems to be the most effective alternative. The benefits of the combined approach of the PVRM concept with the AHP for the rational analysis of conservation strategies for this endangered tree species are discussed.  相似文献   

3.
闽南毛竹林合理经营密度的研究   总被引：5，自引：3，他引：2  
在闽南毛竹分布区的毛竹林分中建立标准地２４７块，利用柯尔莫哥洛夫的正态分布检验法。结合半峰宽理论，分析计算了闽南毛竹林的合理经营密度为１２００株￣１６５０朱／ｈｍ＾２，为闽南毛竹林持续经营提供了理论依据。  相似文献   

4.
Polyphenolics extracted from yaupon holly (Ilex vomitoria, Aquifoliaceae) (YH) leaves were investigated in human colon cells for their chemopreventive and anti-inflammatory activities. An activity-guided fractionation allowed the selection of YH flavonol-rich fraction due to its preferential inhibition of HT-29 colon cancer viability over the normal CCD-18Co colon cells. Quercetin and kaempferol 3-rutinosides, main components identified in this fraction, protected CCD-18Co cells against reactive oxidative species (ROS) in part due to increased activity of antioxidant enzymes. In addition, up-regulation of microRNA-146a (miR-146a) known as a negative regulator of pro-inflammatory NF-κB activation was the underlying molecular mechanism that protected CCD-18Co from inflammation.  相似文献   

5.
以山西省方山县和吉县的刺槐和油松人工林为研究对象,根据调查样地、解析木和气象资料,估算了其耗水量。结果表明:(1)人工林耗水量随林龄增加而增大,达一定林龄后将超过降水量。这个林龄对于位于阳坡的方山县刺槐林为15年;位于半阳坡的吉县刺槐林和油松林分别为5年和23年。(2)在现降水条件下,人工林耗水量达不到需水量,存在着水分不足的胁迫。研究区生长季各月份按耗水量从高至低的排序为:7月,6月,8月,5月,9月,10月,现降水条件限制了人工林需水量及其在生长季内的合理分配。因此,有必要根据现降水条件结合经营目标调控不同生长阶段的林分密度。  相似文献   

6.
Development of understory vegetation has been influenced by the many densely stocked second-growth forest stands in North America, which have an extended stem exclusion successional stage. Understory composition and structure is important for ecosystem functioning, while also having social and economic value through the harvest of certain herb and shrub species. The potential for co-management of young and mature, managed and unmanaged stands for timber and non-timber forest products (NTFPs) was assessed in two separate replicated experiments. Experiment A examined pole-sized lodgepole pine (Pinus contorta) stands that had been pre-commercially thinned (PCT) to target densities of 250, 500, 1000, and 2000 stems/ha. Half of each of these four thinning units was repeatedly fertilized, resulting in eight experimental units. Experiment B examined six different stand types: young plantations, pole-sized lodgepole pine stands either PCT, PCT plus repeated fertilization, or unthinned, mature, and old growth. Fifty-four herb and shrub species were identified as potential NTFPs, with the responses of individual species, as well as mean total herb, shrub, berry-producing and overall total NTFPs being assessed. In Experiment A, mean total abundance (crown volume index) of NTFPs, as well as mean total herb NTFPs were significantly greater in fertilized than in unfertilized stands. Thinning treatments did not significantly affect NTFP volume, however, fertilization treatments produced five significant responses by individual species (Achillea millefolium, Epilobium angustifolium, Taraxacum officinale, Arctostaphylos uva-ursi, Rubus idaeus). In Experiment B, four of the six species responses that were significant had greater abundance in young, managed stands (young plantation, thinned, or thinned-fertilized) than in the unmanaged stands. Mean total NTFP volume and mean total herb NTFP volume also followed this pattern. A. uva-ursi, E. angustifolium, Lonicera involucrata, Sorbus sitchensis and Thalictrum occidentale all had significantly higher abundance in young, managed stands than in all other treatments. Results suggest that co-management for timber and NTFPs is possible in this ecosystem, with further research needed to evaluate livelihood values of these crops.  相似文献   

7.
Deoxyschizandrin and schisantherin A are major bioactive lignans isolated from Fructus schisandrae which has been widely used as a tonic in traditional Chinese medicine for many years. Inhibition of UDP-glucuronosyltransferases (UGTs) by herbal components might be an important reason for clinical herb–drug interaction. The aim of the present study is to investigate the inhibitory effect of deoxyschizandrin and schisantherin A on major UGT isoforms. Recombinant UGT isoforms were used as enzyme source, and a nonspecific substrate 4-methylumbelliferone (4-MU) was utilized as substrate. The results showed that 100 μM of deoxyschizandrin and schisantherin A exhibited strong inhibition on UGT1A3, and negligible inhibition on other tested UGT isoforms. Furthermore, deoxyschizandrin and schisantherin A were demonstrated to inhibit UGT1A3 in a concentration-dependent manner, with IC50 value of 10.8 ± 0.4 μM and 12.5 ± 0.5 μM, respectively. Dixon and Lineweaver–Burk plots showed that inhibition of UGT1A3 by deoxyschizandrin was best fit to competitive inhibition type, and inhibition kinetic parameter (Ki) was calculated to be 0.48 μM. Inhibition of UGT1A3 by schisantherin A gave the best fit for types of noncompetitive inhibition, and the results showed Ki to be 11.3 μM. All these experimental data suggested that herb–drug interaction might occur when deoxyschizandrin or schisantherin A containing herbs were co-administered with drugs which mainly undergo UGT1A3-mediated metabolism. However, given that many in vivo factors could influence the in vitro–in vivo extrapolation (IVIVE), these in vitro inhibitory parameters should be considered with caution.  相似文献   

8.
Angiogenesis, the growth of new blood vessels from the pre-existing vasculature is of physiological and pathological importance. Substantial data over the last decade has implicated uncontrolled angiogenesis with various pathological states. Vascular endothelial growth factors (VEGFs) play a critical role in its regulation, and have become one of the most interesting anti-angiogenesis targets. We have investigated the anti-angiogenic potential of plant extracts in a preliminary ELISA screening. The n-BuOH extract obtained from the leaves of Monnina obtusifolia (Polygalaceae) demonstrated an inhibition of VEGF-A or Placental Growth Factor interaction with Flt-1 (VEGF receptor 1), with an inhibition over 50% in particular for VEGF-A/Flt-1 interaction at a concentration of 500 μg/mL. Successively fractionation of the bioactive n-BuOH extracts of M. obtusifolia aerial parts led to the isolation of six new compounds, 1-O-(4-hydroxy-2-methylene-butanoic acid)-6-O-β-d-(4-hydroxy-2-methylene-butanoyl)-glucopyranose (1), 1-O-(isopentenyl)-6-O-β-d-(4-hydroxy-2-methylene-butanoyl)-glucopyranose (2), 1-O-(4-hydroxy-2-methylene-butanoic acid)-6-O-β-d-(isovaleroyl)-glucopyranose (3), 1-O-(3-methylbut-3enyl)-6-O-β-d-(isovaleroyl)-glucopyranose (4), two new sucrose esters, 3,4-O-β-d-di-feruloyl-fructofuranosyl-6-O-α-d-(p-coumaroyl)-glucopyranoside (5), and 3,4-O-β-d-di-feruloyl-fructofuranosyl-6-O-α-d-(caffeoyl)-glucopyranoside (6), together with known flavonoids. Their structures were established on the basis of detailed spectral analysis. Since none of the isolated compounds showed a relevant inhibition of VEGFs, the biological activity observed for the butanolic extract might be due to the presence of a combination of compounds acting synergistically.  相似文献   

9.
The aim of this study was to determine the effect of whole-tree harvesting (WTH) on the growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) as compared to conventional stem harvesting (CH) over 10 and 20 years. Compensatory (WTH + CoF) and normal nitrogen-based (CH + F or WTH + F) fertilisation were also studied. A series of 22 field experiments were established during 1977-1987, representing a range of site types and climatic conditions in Finland, Norway and Sweden. The treatments were performed at the time of establishment and were repeated after 10-13 years at 11 experimental sites. Seven experiments were followed for 25 years.Volume increment was on average significantly lower after WTH than after CH in both 10-year periods in the spruce stands. In the pine stands thinned only once, the WTH induced growth reduction was significant during the second 10-year period, indicating a long-term response.Volume increment of pine stands was 4 and 8% and that of spruce stands 5 and 13% lower on the WTH plots than on CH during the first and the second 10-year period, respectively. For the second 10-year period the relative volume increment of the whole-tree harvested plots tended to be negatively correlated with the amount of logging residue. Accordingly, the relative volume increment decreased more, the more logging residue was harvested, stressing the importance of developing methods for leaving the nutrient-rich needles on site.If nutrient (N, P, K) losses with the removed logging residues were compensated with fertiliser (WTH + CoF), the volume increment was equal to that in the CH plots. Nitrogen (150-180 kg ha−1) or N + P fertilisation increased tree growth in all experiments except in one very productive spruce stand. Pine stands fertilised only once had a normal positive growth response during the first 10-year period, on average 13 m3 ha−1, followed by a negative response of 5 m3 ha−1 during the second 10-year period. The fertilisation effect of WTH + F and WTH + CoF on basal area increment was both smaller and shorter than with CH + F.  相似文献   

10.
Cucumber (Cucumis sativus L.) is a member of the Cucurbitaceae family like melon, squash and pumpkins. It is a popular vegetable crop used in Indian traditional medicine since ancient times. This vegetable is very high in water content and very low in calories. It has potential antidiabetic, lipid lowering and antioxidant activity. Cucumber has a cleansing action within the body by removing accumulated pockets of old waste materials and chemical toxins. Fresh fruit juice is used for nourishing the skin. It gives a soothing effect against skin irritations and reduces swelling. Cucumber also has the power to relax and alleviate the sunburn's pain. The fruit is refrigerant, haemostatic, tonic and useful in hyperdipsia, thermoplegia etc. The seeds also have a cooling effect on the body and they are used to prevent constipation. Several bioactive compounds have been isolated from cucumber including cucurbitacins, cucumegastigmanes I and II, cucumerin A and B, vitexin, orientin, isoscoparin 2″-O-(6‴-(E)-p-coumaroyl) glucoside, apigenin 7-O-(6″-O-p-coumaroylglucoside) etc. Despite huge exploration of cucumber in agricultural field, comparatively very few studies have been published about its chemical profile and its therapeutic potential. This article reviews the therapeutic application, pharmacological and phytochemical profile of different parts of C. sativus. In this review we have explored the current phytochemical and pharmacological knowledge available with this well known plant and several promising aspects for research on cucumber.  相似文献   

11.
Radix scutellariae was used alone or in combination with other medicinal herbs in the treatment of type 2 diabetes mellitus in China. At present, the pharmacokinetics of baicalin in type 2 diabetic rats following oral administration of Radix scutellariae extract was investigated. The results showed that the pharmacokinetics (especially AUC) of baicalin in type 2 diabetic rats after oral administration of Radix scutellariae extract was remarkably different from that in normal rats. Then the mechanism which resulted in the increased AUC of baicalin in diabetic rats was investigated from system clearance and presystemic metabolism. And it was found that the increased AUC of baicalin in diabetic rats at least partly resulted from higher production of baicalein in the intestinal tract of type 2 diabetic rats. Moreover, the activity of β-glucuronidase in intestinal mucosa of type 2 diabetic rats was demonstrated to be higher than that in normal rats, which confirmed the results above. In conclusion, the pharmacokinetic behavior of baicalin was significantly altered in type 2 diabetic rats after orally administrated Radix scutellariae extract, which may partly result from the increased activity of intestinal β-glucuronidase under the pathological state of type 2 diabetes mellitus.  相似文献   

12.
从环境保护的角度出发,将旅行费用法TCM和费用效益法CBA结合起来,把TCM方法评价出的森林游憩效益纳入了森林的经济收益中,再用CBA法对日本朝日林进行了经济效益评价。评价结果,1997～2001年的游憩效益分别为1079、1084、1211、950、930万日元,B/C比值分别为1 39、1 48、1 29、1 15、1 19,平均值为1 3。这种考虑了森林的公益效益的经济效益评价方法,符合森林的可持续经营理论,比较合理地反映了森林的经济效益,为经营者的合理决策提供了参考。  相似文献   

13.
Pittosporum undulatum Ventenat (Pittosporaceae) is a tree or shrub native to Australia introduced in the Azores Islands in the 19th century, presently naturalized in the nine islands. According to a random survey of vascular plants in the Azores, the invader is present throughout the archipelago, in 62% of 547 1-km2 samples. It was found in pure or mixed stands, forming groups and also as isolated trees. P. undulatum was frequently found in native scrubland (62%), mixed woodland (39%) and hedgerows (25%). The altitudinal range extended from sea level up to about 800 m a.s.l., with the highest frequency between 100 and 400 m. The woody species more strongly associated with P. undulatum included characteristic native and endemic species as well as non-indigenous and invasive taxa. Based on a forest inventory, 49% of the forested area in the Azores, about 24,000 ha, is occupied by P. undulatum. Considerable areas inside Island Natural Parks are covered by this species. The estimated annual P. undulatum biomass production in the Azores might range from only about 150 Mg in the small island of Corvo up to more than 60,000 Mg in Pico Island. The heating value of its wood and its chemical composition make it a good candidate for use in combustion or gasification processes. Since there are no resources available to control this large-scale invasion, using P. undulatum biomass for energy production might be an important factor to stimulate the progressive and sustainable cutting of its stands and its replacement by Macaronesian species.  相似文献   

14.
Schisandra chinensis fruit extract (SCE) has traditionally been used as an oriental medicine for the treatment of various human diseases, including cardiovascular disease. Advances in scientific knowledge and analytical technologies provide opportunities for translational research involving S. chinensis; such research may contribute to future drug discovery. To date, emerging experimental evidence supports the therapeutic effects of the SCE or its bioactive lignan ingredients in cardiovascular disease, unraveling the mechanistic basis for their pharmacological actions. In the present review, we highlight SCE and its lignans as promising resources for the development of safe, effective, and multi-targeted agents against cardiovascular disease. Moreover, we offer novel insight into future challenges and perspective on S. chinensis research to future clinical investigations and healthcare strategies.  相似文献   

15.
The demand for quantifying the biomass of stumps and roots and the carbon stored therein is related to aspects of biodiversity, site productivity, atmospheric carbon cycling issues, and the demand for bioenergy. This, in turn, creates a need to develop high-quality tools for estimating biomass and carbon-equivalents in the ground. The objective of this study was to develop decomposition functions for quantifying the remaining dry weight of the biomass of individual stumps and their associated roots in Norway spruce (Picea abies (L.) Karst.). The negative exponential model was chosen for this purpose, combined with a chronosequence approach, involving 99 stumps and their roots from three sites in Sweden. The results showed a relative decay rate of 4.6% annually for stump and root systems. Based on this rate, the time required for the loss of 50% (t0.5) and 95% (t0.95) of the wood is 15 and 64 years, respectively. Although there are many variables that affect decomposition, residual studies indicated that the remaining biomass could be predicted fairly accurately on the basis of the independent variables stump diameter and time.  相似文献   

16.
The wood panel industry uses a large volume of wood and it is essential to research the use of new tree species for these types of products. As such, the aim of this study was to evaluate the feasibility of Cordia trichotoma (Vell.) wood, both on its own and as a mixture with Pinus spp., as well as to understand the effect on particleboard quality when adding the species’ bark and shavings. The experimental design included nine treatments that assessed various mixture proportations of C. trichotoma and Pinus; for example, 10% bark, and 10% shavings of C. trichotoma with Pinus spp. and C. trichotoma particles, as well as mixtures of these two species in proportions of 25/75%, 50%/50%, and 75/25%. The results indicate that the Cordia trichotoma specie is technically feasible when manufacturing particleboards in pure form. The incorporation of bark (at 10% of the mixture) is also technically feasible. It is also feasible to use the shavings of C. trichotoma. In general, all treatments produced outputs that showed dimensional stability and mechanical strength statistically equal or higher than control treatments (Pinus spp.); thus, these products may be used for non-structural applications in dry and/or moist conditions.  相似文献   

17.
云南切梢小蠹(Tomicus yunnanensis Kirkendall and Faccoli)是云南松(Pinus yunnanensis Franchet)的主要害虫之一[1],该虫于20世纪80年代首次在滇中地区大面积危害,以后蔓延至云南省15个州(市)65个县,迄今已导致6万多公顷云南松林死亡[2-5].2008年以前,该虫曾经长期被认为是纵坑切梢小蠹(Tomicus piniperda L.)[1].与大多数小蠹相似,云南切梢小蠹钻蛀在树皮与边材之间,终生潜伏生活,只有新成虫羽化后的短暂时间飞离树身,在林中活动、觅食、交配,另筑坑道入侵新寄主[6-7].  相似文献   

18.
Neuroinflammatory processes are involved in the pathogenesis of many neurodegenerative disorders. Microglial cells, the main immune cells of the central nervous system, represent a target of interest to search for naturally occurring anti-inflammatory products. In this study, we evaluated the anti-inflammatory properties of polyphenols obtained from the stems of Morus alba. This edible species, known as white mulberry, is frequently studied because of its traditional use in Asian medicine and its richness in different types of polyphenols, some of which are known to be phytoalexins. One new coumarin glycoside, isoscopoletin 6-(6-O-β-apiofuranosyl-β-glucopyranoside) (1) was mainly isolated by CPC (centrifugal partition chromatography) from this plant, together with seven known polyphenols (2–8). Their structures were established on the basis of spectroscopic analyses including extensive 2D NMR studies. The eight isolated compounds were evaluated for their inhibitory activities on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. The absence of cell toxicity is checked by a MTT assay.  相似文献   

19.
本文在对西双版纳现有混农林系统进行广泛调查的基础上,根据国际混农林研究委员会(ICRAF)P.K.R.Nair的分类方法,将其进行了分类和评价。结果表明,该地区现存混农林系统的模式极为丰富,并以经济植物为主体的模式占较大优势。这些模式,有的已经发挥出较好的生态、经济和社会效益,有的仍处于实验阶段,有的则对合理利用当地自然资源造成不良的影响。提出了必须合理开发利用当地自然资源,积极创立和引进以粮食作物为主体的混农林系统模式的见解。  相似文献   

20.
The increment of trees depends, primarily, on the size of the assimilation apparatus of the crown and its efficiency to produce organic matter. That is why this study undertook to determine the size of the assimilation apparatus of single trees of Pinus sylvestris L. The authors used the mass (ugc) and volume (ugo) of twigs covered with needles in order to estimate the size of the assimilation apparatus. The performed analysis revealed a significant correlation between easy-to-determine tree variables: breast height diameter—d1.3, height—h and age—w and the ugc and ugo. This correlation served as a basis for the elaboration of equations which allow determining the size of the assimilation apparatus. The empirical material was provided by the results of measurements carried out on 1808 pine trees growing in mesic forest sites typical for this species in western Poland.  相似文献   

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