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1.
Withania somnifera is one of the most important medicinal plants of Ayurveda and finds extensive uses in Indian traditional herbal preparations. In this investigation, selected accessions of the plant were examined for diversity through RAPDs, isoenzymes, polypeptide polymorphism and withanolide profiles. The accessions clustered together with respect to their characteristic profile of major withanolides and represented withaferin A, withanone, withanolide D or withanolide A rich groups. This level of phytochemical diversity as discrete chemotypes is widest and is being first ever documented to occur in Indian population of the plant.  相似文献   

2.
Largely widespread in tropical countries, Ocimum gratissimum has been claimed for many uses in folk medicine. Recent research on its essential oils showed five chemotypes. An Indian chemotype, with a high level of ethyl cinnamate, presents, in vitro, an interesting spectrum of antifungal properties.  相似文献   

3.
A photo-based method for statistical image analysis of microwave (MW)-modified timber was developed and applied to test sets of Radiata pine and eucalypt hardwoods (Messmate and Mountain Ash). The method is based on filling the checks in timber with stain solution and analysing the wood surface. Bethel impregnation process (in a pressurised treatment vessel) was used to produce uniform surface staining of the test samples. Image processing was automated and the number of manual operations (the human decision-making process) was minimised. A computer program that automates thresholding and a program that repairs the threshold image were written. The software allowed larger images to be analysed and reduced image processing time. The described method produced reliable check measurements and statistics for softwoods. Though suitable for estimating the quality of individual MW-modified hardwood specimens, the method was found to be inadequate for statistical analysis of eucalypt hardwoods because of collateral staining of vessels accompanied with a high level of stain penetration into the wood tissues.  相似文献   

4.
细毛樟(Cinnamomum tenuipilum Kostern)系樟科樟属植物,根据精油主成分的不同将细毛樟分为不同的化学型,如细毛香樟(香叶醇geraniol为精油主成分)、细毛芳樟(芳樟醇linanol为精油主成分)等。在引种驯化的过程中发现细毛樟种子苗精油主成分变化相当大,一般解释为遗传分离的结果。本文以细毛香樟和细毛芳樟的种子苗为材料,研究樟叶在生化实验中的一些内源干扰问题,探讨子代精油变异与同工酶的关系,为系统地研究细毛樟精油的生物合成控制打下基础。  相似文献   

5.
Jatropha curcas L. is being promoted by governments for greening marginal areas for rural development and biodiesel production in sub-Saharan Africa, however large gaps in knowledge on its agronomy and yield potential exist. The effect of duration of storage at room temperature, pre-sowing seed treatment of Jatropha seed and fruit colour harvest index on germination and seedling growth parameters was investigated. There was a significant negative correlation between the duration of storage of Jatropha seed and seed oil content (P < 0.001, r = ?0.99), viability (P < 0.01, r = ?0.93), percent germination (P < 0.05, r = ?0.90) and germination index (P < 0.05, r = ?0.89). The relationship between duration of seed storage and seed oil content and seed germination parameters was best described by quadratic and exponential functions which showed rapid declines in seed oil content and germination parameters in the first 3 years of storage and a slower decline between 3 and 8 years of storage. There was a significant negative correlation between duration of storage and seedling height (P < 0.01, r = ?0.97), stem diameter (P < 0.01, r = ?0.93) and dry weight (P < 0.05, r = 0.91) that was best described by quadratic functions. Seed oil content was significantly and positively correlated to seed viability (P < 0.01, r = 0.96), germination per cent (P < 0.01, r = 0.94) and germination index (P < 0.01, r = 0.93). The relationship between seed oil content and seed germination parameters was best described by exponential functions which showed an exponential increase in seed germination parameters as oil content increased above 30% and smaller increases below 30% oil content. Progressive peroxidation of lipids as seed aged explains the loss of oil from the seed. Peroxidation of lipids produced highly reactive radicals that damaged membranes and proteins reducing seed germination and seedling growth parameters as seed aged. Pre-sowing seed treatments (seed soaking and scarification) produced marginal gains in germination and seedling growth parameters in Jatropha seed stored for 3 months to 8 years. Seeds harvested at the yellow fruit maturity index, 60 days after anthesis (DAA), showed the highest seed germination percent while seed harvested at the black fruit maturity index, 75 DAA, had the highest oil content. Harvesting of Jatropha seed for oil expression is therefore recommended at the black maturity index while harvesting for seed is recommended at the yellow maturity stage. The results of this study indicate that Jatropha seed should be stored for as short a period of time as possible to maximize seed germination, seedling growth and oil yield.  相似文献   

6.
近年来草酸钙(草酸垢)的形成在制浆造纸工业中造成诸多问题,因此如何分析及控制漂白废液中的草酸浓度就显得尤为重要.高效液相色谱和离子交换色谱等色谱法一般可以作为测定草酸的标准方法.本研究以一个基于阴离子交换柱的离子交换色谱法作为对照方法,利用一套配备了Aminex HPX-87H液相色谱柱的高效液相色谱系统测定漂白废液中的草酸浓度.结果显示,漂白废液中含有一些干扰高效液相色谱法测定的化合物.通过采用稀释样品后再经活性炭吸附的处理方法,可以得到较为满意的结果.分析发现高效液相色谱法与离子交换色谱(对照法)之间的相关性较好,相关系数为0.994.该方法的建立将有利于监控制浆造纸企业中闭路循环漂液中形成草酸钙时的临界草酸浓度.  相似文献   

7.
Negash  Legesse 《New Forests》2003,26(2):137-146
A rapid vegetative propagation method is described for Olea europaea L. subsp. cuspidata [Wall. ex DC.) Ciffieri (syn. Olea africana Mill.)]. Leafy branch cuttings were harvested from 6 to 7-month-old stecklings (= plants derived from rooted cuttings). Cuttings 2–3 mm in basal diameter were trimmed to 70–100 mm in length, with leaf areas reduced to 15–33 cm2. Indolebutyric acid (IBA) was applied at 0, 10, 20, 25, 30, 35 and 40 µg/cutting to each of the 70–80 replicate cuttings randomly allocated to each of the 7 treatments. Callusing and rooting occurred 3–5 and 5–7 weeks after treatment, respectively. The rooting success of cuttings treated with 20 or 40 µg IBA/cutting was 75 and 90%, respectively. Differences in rooting success, speed of rooting and root numbers between the control and the IBA treatments were significant (p < 0.01). Compared to seedlings of similar shoot height, rooted cuttings grew significantly (p < 0.01) faster and produced more biomass. It is concluded from this study that the rooting of leafy branch cuttings derived from young stockplants of wild olive is rapid, and that vegetative propagation is an effective means of regenerating this valuable, yet threatened, tree species.  相似文献   

8.
Summary A simple method for rearing Clysia ambiguella (Lepid., Tortricidae) A method for mass rearing the vine grape tortricid,Clysia ambiguella, in laboratory is described. The moths lay their eggs into folded folies of plastics. The caterpillars are feeded with vine leaves (stored in a freezer). Since spring of 1973 six generations of the pest were reared in succession.   相似文献   

9.
Variations in the compositions of low-boilingpoint (LBP) monoterpenes in needle samples of 50 hinoki (Chamaecyparis obtusa) trees were investigated using the headspace technique. Considerable compositional variations were revealed, especially in sabinene composition. The sabinene composition varied from 4.9% to 78.0% of the total LBP monoterpenes.-Pinene, myrcene, and limonene also showed considerable variations (9.0%–32.7%, 5.5%–22.6%, 3.6%–29.0% respectively). Analysis of the monoterpene composition allowed definition of four chemotypes based on the contingency table test. No correlation was observed between tree size and LBP monoterpene composition, indicating that the compositional variation in LBP monoterpene exists genetically in this population of hinoki.Part of this paper was presented at the 11th annual meeting of the Chugoku Shikoku branch of the Japan Wood Research Society, Matsue, September 1999  相似文献   

10.
A stemflow measurement technique is described, based on: (1) correlations between stemflow volume and tree diameters at breast height (DBH), determined on the basis of a relatively low number of tree samplings; (2) the distribution of trees in the stand relative to their DBH. Stemflow for trees in a stand (mm) can thus be determined from total rainfall (mm). The results were compared to those obtained with two other stemflow determination techniques. The proposed method was found to be more reliable, precise and easier to apply than the standard methods.  相似文献   

11.
正交试验法优选秦皮香豆素醇提工艺   总被引:2,自引:1,他引:1  
研究了秦皮主要活性成分秦皮香豆素的最佳醇提工艺,并采用了毛细管区带电泳(CZE)快速分析了秦皮苷、秦皮甲素、秦皮乙素的含量.以3种秦皮香豆素含量作为考察指标,采用L9(34)正交表,通过考察乙醇体积分数、提取次数、提取时间和料液比4个因素对醇提效果的影响,得到秦皮最佳提取条件为:以体积分数65%的乙醇为提取溶剂,在料液比1:9(g:mL)的条件下,回流提取3次,每次1 h.秦皮总香豆素的得率为3.61%.  相似文献   

12.
长沙市城乡交错带4种人工林土壤养分及其相关性研究   总被引:1,自引:0,他引:1  
以长沙市城乡交错带4种人工林为研究对象,对各林分林下土壤理化性质进行比较分析,揭示了土壤养分间的相互关系,结果表明:土壤物理性质指标垂直分布规律明显,同一林分内土壤容重基本上随土层深度增加而增大,毛管孔隙度、总孔隙度和自然含水率相反;土壤容重与毛管孔隙度、总孔隙度呈极显著的负相关(P<0.01),与自然含水率呈显著的负相关(P<0.05);毛管孔隙度与总孔隙度呈极显著的正相关(r=0.943,P<0.01);自然含水率与总孔隙度呈显著正相关(P<0.05),与毛管孔隙度呈极显著正相关(r=0.815,P<0.01);各林分内不同土层土壤各化学性质指标垂直分布规律明显,基本上随土层深度增加而减小;土壤pH值与土壤养分因子的相关系数值均为负数,与速效氮含量显著负相关(r=-0.661,P<0.05),土壤有机质与全氮、全磷、全钾、速效钾含量相关性显著(P<0.05),与速效氮呈极显著正相关(r=0.760,P<0.01);土壤全量养分与有效养分间均呈显著的正相关。  相似文献   

13.
The role of Accacia nilotica (Sunt) in the Sudan is discussed. The various site types are described and average site index curves for each type derived and compared. Sets of harmonized site index curves for two main site groups are then presented. A method for determining height-diameter relationships of use in inventory is described. The methodology for the production of a series of local volume tables (tariff tables) for Sunt is given. The influence of these aids on the management of Sunt is considered.  相似文献   

14.
A method was developed using matrix solid-phase dispersion and liquid chromatography with ultraviolet diode array detection for the determination of bromopropylate, clofentezine, coumaphos, difenoxuron, diniconazole, fenvalerate, flumetralin, fluometuron, and teflubenzuron in the stem of coconut palm. The parameters evaluated included the type of sorbent (C18-bonded silica, neutral alumina, silica gel, and Florisil) and the volume of the eluting solvent, acetonitrile. The best results were obtained using 0.25 g of stem, 1.0 g of neutral alumina as sorbent, and 5 mL of acetonitrile. The method was validated using stem samples spiked with pesticides at different concentration levels (0.01–10.0 µg mL?1). Average recoveries (using three replicates) ranged from 70 to 91 %, with relative standard deviations between 1.6 and 10 %. Detection and quantification limits were in the ranges 0.01–0.05 and 0.05–0.2 µg g?1, respectively.  相似文献   

15.
Fuzzati N  Pace R  Villa F 《Fitoterapia》2003,74(3):247-256
Extracts from the leaves of Ginkgo biloba are among the most widely used phytotherapeutics. Some alkylphenols (ginkgolic acids, cardanols and cardols) have been described as potentially hazardous constituents in Ginkgo extracts. Accordingly, a requirement for a maximum concentration of ginkgolic acids has been proposed in the UE and US pharmacopoeias Ginkgo monographs establishing a limit value of 5 ppm. A novel HPLC-UV method, developed by the use of HPLC-APCI-MS HPLC-DAD techniques and allowing the identification of ginkgolic acids and related phenols, is described. The new analytical method, not requiring enrichment procedures, can be used for the quantification of ginkgolic acids in Ginkgo extracts.  相似文献   

16.
以加工淀粉后的野葛残渣为原材料,以进食量、食物利用系数、小肠推进率、小肠吸收为评价指标,分别讨论了以酶法和化学法制备的葛根膳食纤维对小白鼠消化吸收功能的影响情况.结果表明:与空白对照组相比,酶法和化学法制备的中、高浓度的膳食纤维能显著地促进小白鼠的摄食量和体质量(p<0.01),酶法制备的中浓度膳食纤维可显著增加小白鼠的食物利用系数(p<0.05);酶法制备的中、高浓度的膳食纤维和化学法制备的中浓度的膳食纤维可显著增加小白鼠的小肠推进率(p<0.01),并能明显增强小白鼠的小肠吸收能力,从而促进小白鼠的正常生长.  相似文献   

17.
Qu LP  Fan GR  Peng JY  Mi HM 《Fitoterapia》2007,78(3):200-204
A method for the isolation of six isoflavones (genistein, genistin, daidzein, daidzin, glycitein and glycitin) with high purity from Semen sojae praeparatum, a famous traditional Chinese medicine, by preparative HPLC is described.  相似文献   

18.
以3月生、5个来源不同桐花树母株的子代苗为研究对象,分析比较了不同桐花树母株其子代苗的苗高、分枝数和存活率的差异,探讨不同母株对子代苗生长适应性的影响.结果表明:桐花树5个母株子代苗苗高均值为22.5cm,单株苗高变异比较大,总的变异系数37.2%,母株子代苗高平均值大小依次为:母株1>母株3>母株4=母株2>母株5;母株1的子代苗的分枝数最多(BN=3.6枝),而母株2子代苗的分枝数最少(BN=2.9枝),总平均为3.3枝.保存率总平均值为81.4%,变异程度在3个指标中最大(47.9%),其中来源母株1的苗保存率最大(SR=89.7%),而母株3苗的保存率最小(SR=74.6%),而母株2和母株5相差不大.因子分析表明:桐花树子代苗的苗高在区组重复之间差异显著(P<0.01),在分枝数上,母株因子效应显著(P<0.01),苗高和分枝数在区组与母株之间均存在显著的交互作用.对桐花树生长以及适应性指标综合评估表明,以母株1子代苗生长适应性面表现优良,其次为母株5,母株3在排名靠后.  相似文献   

19.
贾婷  朱万龙 《绿色科技》2021,(6):150-152
为了验证高糖高脂食物是否会引起高山姬鼠的瘦素抵抗的发生,将高山姬鼠分为两组,一组为对照组,一组为高糖高脂组,各自驯化28 d。结果表明:第28 d,高糖高脂组高山姬鼠的体重和体脂极显著高于对照组(体重:t=-11.97,P<0.01;体脂:t=-7.99,P<0.01),摄食量和血清瘦素含量显著高于对照组(摄食量:t=-3.06,P<0.05;血清瘦素含量:t=-2.94,P<0.05)。血清瘦素含量与体脂呈显著正相关(r=0.636,P<0.01),与摄食量呈极显著正相关(r=0.744,P<0.01)。分析以上结果表明:在高糖高脂食物条件下,高山姬鼠会增加体重、摄食量和血清瘦素含量。此外,高山姬鼠在该条件下可能存在瘦素抵抗。  相似文献   

20.
富马海松酸的制备(英文)   总被引:4,自引:2,他引:2  
介绍了山乔松(印度兰松)(Pinus wallichiana)松脂直接制备富马海松酸(FPA)的二种实验室方法:(1)松脂200克、富马酸20克、乙醇1000毫升置三颈瓶中混合并回流48小时,静置过夜、减压吸滤分离出粗FPA,冷乙醇洗数次得纯FPA晶体,190~230℃真空干燥3小时,得率48%,酸价420,熔点295~298℃,[α]D(CHCl_3)±42.5~0;(2)松脂200克、富马酸35克置三颈瓶中在220—225℃下激烈搅拌3小时,由冷却器收集松节油,瓶中粗FPA冷却后加入苯、乙醇混合液(15:85)500毫升,混匀过夜,减压吸滤分离出粗FPA,以冰冷苯、乙醇(15:85)混合液洗数次,得纯FPA纯白色晶体,190—230℃真空干燥2.5小时,得率42%,酸价420,熔点285—287℃,[α]D(CHCl_3)+42.7℃。 纯FPA作了红外、核磁共振、质谱和气液色谱仪器分析予以证实。  相似文献   

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