毛脉酸模不同器官中几种生物活性物质的含量及生长季节对其的影响

为确定毛脉酸模(Rumex gmelini)最佳药用部位和最佳采收期, 从而为新药源开发提供科学依据, 我们采用HPLC法和梯度洗脱, 研究了一年生和二年生毛脉酸模不同生长发育期、不同器官、组织中7种生物活性成分(白藜芦醇、白藜芦醇苷、大黄酚苷、酸模素、大黄素、大黄酚和大黄素甲醚)的动态分布规律。结果表明毛脉酸模根部含有生物活性成分的种类及含量均多于其他部位, 为最佳药用部 位。一年生毛脉酸模根部不含有酸模素。二年生毛脉酸模根部含有全部7种生物活性成分, 且在8~9月份含量最高, 为最佳采收期。     

毛脉酸模内生真菌蒽醌类次生代谢产物的筛选及含量分析

本文通过对毛脉酸模内生真菌的发酵培养得到其次生代谢产物,采用HPLC法对内生真菌中蒽醌类成分进行筛选。以大黄素、大黄酸、大黄酚、大黄素甲醚、芦荟大黄素五种蒽醌类成分为参照,筛选出3株真菌含大黄素、3株真菌含大黄酸、5株真菌含芦荟大黄素,其中含量最高为683μg/g、最低为8μg/g。将各菌株所含成分与各菌株分离部位的相应成分进行比较,相对宿主植物而言各菌株均有较高的含量。本实验分析方法准确、快捷,适用于毛脉酸模内生真菌的代谢产物研究。     

光强对毛脉酸模根中白藜芦醇和白藜芦醇苷的影响

在人工控制条件下,观察了光强对毛脉酸模根中白藜芦醇和白藜芦醇苷的影响.结果表明,较短时期的遮荫使毛脉酸模根中白藜芦醇和白藜芦醇苷含量随着遮荫程度的增加而增加,较长时期的遮荫则使白藜芦醇和白藜芦醇苷含量降低;随遮荫程度和遮荫时间的增加,根中白藜芦醇和白藜芦醇苷含量显著降低.根中白藜芦醇产量在8月份达最大值、白藜芦醇苷产量在9月份达最大值,遮荫降低根中白藜芦醇和白藜芦醇苷的产量.在毛脉酸模生长后期给予短期深度遮荫可以提高白藜芦醇和白藜芦醇苷产量.     

不同光质对毛脉酸模中蒽醌类成分的影响

通过红色、黄色、绿色、蓝色滤光膜对毛脉酸模进行遮膜处理。采用高效液相色谱法对毛脉酸模根样品中的蒽醌类成分含量进行测定,研究光质对毛脉酸模根次生代谢产物蒽醌类成分的影响。进行了方差分析。二年生黄膜处理中蒽醌类成分含量显著性高于处理组及空白组。一年生空白组及对照组中蒽醌类成分含量显著性高于处理组。结果表明黄膜处理显著提高二年生毛脉酸模中中蒽醌类成分含量。     

三株长蠕孢属真菌对毛脉酸模幼苗中白藜芦醇、白藜芦醇苷含量和产量的影响

以幼苗期毛脉酸模（Rumex gmelini Turcz.）为实验材料, 研究经长蠕孢属真菌（Helminthosporium carbonum）侵染后毛脉酸模中白藜芦醇和白藜芦醇苷的含量和产量的变化。实验结果表明：幼苗期毛脉酸模中的白藜芦醇在受到外界真菌诱导时对真菌具有一定的选择性。而且同一真菌的不同菌株诱导强度也有一定的差异,主要表现在起效时间上。但白藜芦醇苷含量受外界真菌诱导的专属性不强,且影响强度与诱导浓度有关。对幼苗期毛脉酸模各种诱导处理都没有使其生物量受到明显的抑制。通过试验筛选出大斑病长蠕孢001使幼苗期毛脉酸模中白藜芦醇苷和白藜芦醇产量影响较大,与对照相比分别使其提高1.54倍和3.99倍。     

三株长蠕孢属真菌对毛脉酸模幼苗中白藜芦醇、白藜芦醇苷含量和产量的影响

以幼苗期毛脉酸模（Rumex gmelinii Turcz．）为实验材料,研究经长蠕孢属真菌（Helminthosporium carbonum）侵染后毛脉酸模中白藜芦醇和白藜芦醇苷的含量和产量的变化。实验结果表明：幼苗期毛脉酸模中的白藜芦醇在受到外界真菌诱导时对真菌具有一定的选择性。而且同一真菌的不同菌株诱导强度也有一定的差异,主要表现在起效时间上。但白藜芦醇苷含量受外界真菌诱导的专属性不强,且影响强度与诱导浓度有关。对幼苗期毛脉酸模各种诱导处理都没有使其生物量受到明显的抑制。通过试验筛选出大斑病长蠕孢001使幼苗期毛脉酸模中白藜芦醇苷和白藜芦醇产量影响较大,与对照相比分别使其提高1．54和3．99倍。     

青海栽培和野生唐古特大黄蒽醌类成分的HPLC对比分析

采用HPLC法测定青海栽培唐古特大黄中的5种蒽醌含量,并和野生唐古特大黄药材进行了比较.结果表明,二、三、四年龄栽培唐古特大黄中芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚5种蒽醌总量分别为1.21%,2.01%,1.62%,其中三、四年龄栽培唐古特大黄已达到<药典>规定的药用标准;野生大黄的总蒽醌含量远高于栽培大黄为3.64%.     

斑马鱼模型评价何首乌中18种成分的肝脏毒性

首次用斑马鱼模型探索何首乌中18种成分的肝脏毒性作用,为何首乌的肝毒性物质基础研究提供依据。对肝脏荧光转基因斑马鱼给以高、中、低剂量的18种何首乌主要成分72 h,并分别于给药后24、48、72 h用荧光显微镜对其进行拍照。拍好的图片通过Image J软件进行肝脏面积和荧光强度分析。大黄素组、大黄酸组、芦荟大黄素组、大黄素-1-O-葡萄糖苷组、大黄素甲醚-8-O-葡萄糖苷组、芦荟大黄素-8-O-葡萄糖苷组及阳性对照组(对乙酰氨基酚)的肝脏面积和肝脏荧光强度与空白组相比显著降低;而大黄酚组、大黄素甲醚组、大黄素-8-O-葡萄糖苷组、大黄酸-8-O-葡萄糖苷组、大黄酚-1-O-葡萄糖苷组、大黄酚-8-O-葡萄糖苷组、芦荟大黄素-3-羟甲基葡萄糖苷组、白藜芦醇组、没食子酸组、儿茶素组、表儿茶素组的肝脏面积和肝脏荧光强度与空白组相比无显著差异;此外,二苯乙烯苷组的肝脏荧光强度与空白组相比显著增高。由此可见大黄素、大黄酸、芦荟大黄素、大黄素-1-O-葡萄糖苷、大黄素甲醚-8-O-葡萄糖苷、芦荟大黄素-8-O-葡萄糖苷对斑马鱼幼鱼肝脏具有一定毒性作用。何首乌的肝毒性作用可能还是由蒽醌类化合物介导,其物质基础与上述6种蒽醌成分有关,并以结合蒽醌为主。     

RP-HPLC法同时测定虎杖中白藜芦醇和白藜芦醇苷的含量

建立了国内首次用RP-HPLC同时测定虎杖中白藜芦醇和白藜芦醇苷含量的方法,并详细考察了2个指标成分的稳定性。对不同产地的虎杖药材、不同采收期的虎杖根及根茎以及虎杖的不同部位共25个样品中的白藜芦醇和白藜芦醇苷进行了含量测定,考察了两种活性成分的含量与产地、采收期及部位的关系,为虎杖资源的合理采收利用及进一步的研究提供了理论依据。     

HPLC法分析不同年限及不同部位掌叶大黄9种成分的积累特征

为研究不同年限及部位掌叶大黄9种成分含量及其变化特征。利用HPLC法进行分析,色谱柱为武本C18 (5μm,4.6 mm×250 mm),流动相为甲醇-磷酸水(0.2%),检测波长260 nm,柱温30℃,体积流量1.0 mL/min,进样量10μL。线性范围良好(R^2>0.995),精密度、稳定性、重复性RSD均小于2%,加样回收率97.30%~108.20%。含量分析表明:同一部位,随着年限增加,除根中没食子酸、根茎中大黄素、叶片中大黄酚的含量无变化外,其他8成分的含量均随年限增加而增加或者第4年增加、第5年无显著变化。同一年限,大黄酚-8-O-葡萄糖苷、大黄素、大黄酚、大黄素甲醚的含量次序为根>根茎>叶片;3年生芦荟大黄素,4年生没食子酸、番泻苷B叶片中含量与根中大致相等且高于根茎;5年生大黄素-8-O-葡萄糖苷的含量次序为叶片>根茎>根,根与根茎中没食子酸、大黄酚的含量相当且高于叶片。本实验成功建立简便快捷、重现性好的HPLC分析方法,明确了不同年限及部位掌叶大黄9种成分积累特征,为大黄质量评价和药材高效生产提供理论依据。     

毛脉酸模根中一新的色原酮苷类化合物

从毛脉酸模根(Rumex gmelini Turcz.)75%乙醇提取物中分离得到1个新色原酮苷和5个已知化合物,应用波谱学方法及文献对照分别鉴定为2,5-dimethyl-7-hydroxychromone-7-O-β-glucopyranoside (1),nepodin-8-O-β-D-glucopyranoside (2),10-hydroxyaloin A (3),10-hydroxyaloin B (4),5-methoxyl-1(3H)-benzofuranone-7-O-β-D-glucopyranoside (5),phenylethyl-O-α-L-arabinopyranosy-(1→6)-O-β-D-glucopyranoside (6). 其中化合物1为新化合物,3～6首次从酸模属中分离得到,化合物2首次从该植物中分离得到.     

The timing of grain Cd accumulation in rice plants: the relative importance of remobilisation within the plant and root Cd uptake post-flowering

The pathways by which Cd is accumulated in rice grain are not well understood, in particular the components attributable to direct transfer from the root, and to remobilisation of Cd previously accumulated in other plant parts. In order to observe the timing of Cd accumulation in rice plants and determine the major period for accumulation of Cd which can be translocated to the grain, Cd was supplied to the roots of rice plants grown under static hydroponic conditions at a non-toxic, environmentally relevant concentration (50 nM), according to three different timing regimes: (1) Pre-flowering Cd, (2) Post-flowering Cd, or (3) Continuous Cd. The rate of accumulation of Cd in the developing grain was monitored by harvesting immature rice panicles at four time points prior to a final harvest. Nearly all grain Cd was accumulated within 16 days of anthesis and the contribution of post-flowering Cd uptake was evident from 7 days after flowering. It was estimated that 60% of the final grain Cd content was remobilised from that accumulated by the plant prior to flowering and the other 40% came from uptake during grain maturation. This study shows that Cd uptake from the root to the grain in rice is indeed possible post-flowering and it is an important source of grain Cd.     

Growth,nutrition and gas exchange of Pinus resinosa following artificial defoliation

Summary In three experiments, red pine (Pinus resinosa Ait.) seedlings and trees were subjected to artificial defoliations of varying intensities and subsequent growth, gas exchange and nutritional responses were monitored. In Experiment 1, 2-year-old seedlings received 0, 1 or 2 50% defoliations during a single growing season and were maintained in 1 of 3 low nutrient supply treatments. In Experiment 2, response of 4-year-old seedlings was monitored in the year following 0, 25, 50 or 75% defoliation, while in Experiment 3, response of 11-year-old trees was measured 1 year after being defoliated by 0, 33 or 66%. Regardless of intensity of defoliation, or plant size, clipped plants made qualitatively similar allocational and metabolic adjustments over time. First, leaf diffusive conductance and rates of net photosynthesis were stimulated, especially by light to intermediate defoliation. However, there was no effect of defoliation on foliar nitrogen concentration, and elevated gas exchange rates apparently resulted from altered root-shoot dynamics. Second, allocation of new biomass was preferentially shifted towards foliage at the expense of roots, gradually restoring (but undershooting or overshooting) the ratio of foliage: roots of control plants. During the period when foliage: root balance was being restored, the stimulation of needle gas exchange rates disappeared. Plants defoliated by 25% overcompensated in terms of whole plant growth (were larger at harvest than controls), due to shifts in allocation and enhanced photosynthesis. Defoliated plants also stored a proportionally greater share of their carbohydrate reserves in roots than did control plants, even 1 year after clipping.     

Exogenous cadaverine induces oxidative burst and reduces cadaverine conjugate content in the common ice plant

The effect of free cadaverine (Cad) on its conjugates formation was analyzed in roots of the common ice plants (Mesembryanthemum crystallinum L.). It was found for the first time that Cad could induce oxidative burst in the roots of adult plants, as was evident from the sharp decrease in the content of Cad soluble or insoluble conjugates. This unusual effect was associated with the increased oxidative degradation of exogenous Cad (1mM, 1.5h) and intense H(2)O(2) production in the root cells of adult plants. Root treatment of both juvenile and adult plants with H(2)O(2) (1mM, 1.5h) reduced the content of soluble Cad conjugates and increased the content of their components, free Cad and phenols. We also found that one of the possible reasons of the negative effect of exogenous diamine on the formation of conjugated forms in adult roots was alkalization of the root apoplast at Cad addition to nutrient medium and the unusual O(2)(-) synthase function as a pH-dependent guaiacol peroxidase in the presence of a high content of H(2)O(2). This was confirmed by the data on the accumulation of O(2)(-) and enhanced superoxide dismutase activity in adult roots under treatment with Cad. It is possible that the accumulation of O(2)(-) together with H(2)O(2) was also responsible for oxidative burst, which induced a decrease in the content of Cad conjugates in adult roots of the common ice plants.     

Root uptake, transport, and metabolism of externally applied glutathione in Phaseolus vulgaris seedlings

The most abundant thiol in beans (Phaseolus vulgaris L. cv. Saxa) is the tripeptide homoglutathione (hGSH) rather than glutathione (GSH). At the whole-plant level the GSH content is less than 0.5% of the hGSH content. In the present study GSH was supplied to the roots of bean seedlings to test whether GSH can be taken up by roots and transported to the shoot. Therefore, 12-day-old plants were exposed to 1 mmol/L GSH for 4, 8 and 24 h prior to harvest. In response to this GSH exposure, elevated GSH contents were found in all tissues. After 4 h the GSH content increased in the roots from 1 +/- 1 to 22 +/- 2 nmol GSH g(-1) fresh weight (FW), in the leaves from 2 +/- 1 to 9 +/- 4 nmol GSH g(-1) FW, and in the apex from 30 +/- 5 to 75 +/- 4 nmol GSH g(-1) FW. These data indicate that GSH is taken up by bean roots and is transported to above above-ground parts of the plants. Roots exposed to GSH for 24 h contained 2-fold higher cysteine (Cys) and hGSH contents than the controls. Apparently, GSH taken up by the roots is not only loaded into the xylem but also partially degraded and used for hGSH synthesis.     

Seasonal Accumulation of Starch by Components of the Kiwifruit Vine

The accumulation of starch by various components of 6-year-oldkiwifruit vines (Actinidia deliciosa var dehciosa cv Hayward)was recorded over one season Twenty vines were harvested periodicallythroughout the year and separated into perennial components(fibrous roots, structural roots, stump, stem, cordon, laterals)and current season's growth (shoots, leaves, and fruit) The concentration of starch in the fibrous roots followed asinusoidal trend Minimum concentrations occurred 98 d afterbudbreak, while the maximum concentrations occurred 182 d laterCorresponding times in the structural roots were approximately42 d earlier In the above-ground perennial components, elevatedconcentrations of starch in the cordon, fruiting wood and barkof the stem were evident at budbreak and fruit harvest (approx220 d later) In the case of the stem, concentrations were greatestat fruit harvest Because the biomass of the perennial componentswas found to be relatively constant throughout the year, starchconcentrations and contents were directly proportional in thesetissues For current season's growth, peak concentrations and contentsin leaves and shoots were observed at fruitset and fruit harvest,respectively For fruit, starch increased continuously untilharvest Approximately 30% of the total starch content accumulated inthe perennial components by leaf abscission was lost duringwinter and early summer Quantitative losses were greatest forthe roots Regeneration of the starch pools in the perennialcomponents of the vine occurred from midseason until leaf abscissionAt the same time, approximately five times more starch was accumulatedby the current season's growth, in particular the fruit, thanby the perennial components As a result of the difference inthe rate of accumulation, the starch content of the currentseason's growth increased from less than 10% midseason to nearly60% of the total starch content of the vine by fruit harvest The results were discussed in relation to the carbon economyof the kiwifruit vine, and compared with seasonal trends instarch concentrations found for other deciduous crops Actinidia deliciosa, kiwifruit, seasonal changes, starch content, whole plant     

Short term physiological implications of NBPT application on the N metabolism of Pisum sativum and Spinacea oleracea

The application of urease inhibitors in conjunction with urea fertilizers as a means of reducing N loss due to ammonia volatilization requires an in-depth study of the physiological effects of these inhibitors on plants. The aim of this study was to determine how the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) affects N metabolism in pea and spinach. Plants were cultivated in pure hydroponic culture with urea as the sole N source. After 2 weeks of growth for pea, and 3 weeks for spinach, half of the plants received NBPT in their nutrient solution. Urease activity, urea and ammonium content, free amino acid composition and soluble protein were determined in leaves and roots at days 0, 1, 2, 4, 7 and 9, and the NBPT content in these tissues was determined 48 h after inhibitor application. The results suggest that the effects of NBPT on spinach and pea urease activity differ, with pea being most affected by this treatment, and that the NBPT absorbed by the plant caused a clear inhibition of the urease activity in pea leaf and roots. The high urea concentration observed in leaves was associated with the development of necrotic leaf margins, and was further evidence of NBPT inhibition in these plants. A decrease in the ammonium content in roots, where N assimilation mainly takes place, was also observed. Consequently, total amino acid contents were drastically reduced upon NBPT treatment, indicating a strong alteration of the N metabolism. Furthermore, the amino acid profile showed that amidic amino acids were major components of the reduced pool of amino acids. In contrast, NBPT was absorbed to a much lesser degree by spinach plants than pea plants (35% less) and did not produce a clear inhibition of urease activity in this species.