不同变异类型杜仲皮中几种主要活性成分含量的比较

采用反相高效液相色谱法测定了不同变异类型杜仲皮中几种关键活性成分的含量,结果表明:4种变异类型杜仲皮中5种不同活性成分的含量及组成比有较大差异,其中京尼平苷酸(GPA)、京尼平苷(GP)、松脂素二糖苷(PDG)、绿原酸(CA)含量以及5种成分的总含量以光皮型和浅纵裂型杜仲皮较高,而龟裂型和深纵裂型活性成分总体含量较低....     

杜仲主要活性成分含量及其与树龄和部位的相关性

【目的】为给杜仲保健食品的开发提供参考,测定不同树龄杜仲不同部位的主要活性成分含量,并对其进行相关性分析。【方法】采用紫外分光光度法测定杜仲样品中总木脂素、总环烯醚萜、总苯丙素和总黄酮4类化合物的含量;采用HPLC变波长-梯度洗脱法,同时测定杜仲中12种环烯醚萜类、木脂素类和苯丙素类活性成分的含量;采用HPLC变波长-梯度洗脱法,同时测定杜仲中5种黄酮类活性成分的含量。【结果】采用紫外分光光度法测定的杜仲样品中4类化合物含量的线性范围良好,相关系数均在0.99以上;采用高效液相色谱法测定的杜仲17种活性成分的精密度、重复性、稳定性和加样回收率的相对标准偏差值均在5%以内。杜仲叶中黄酮类与苯丙素类成分含量最高,环烯醚萜类成分含量次之;杜仲枝皮中主要含有木脂素类成分;杜仲干皮中木脂素类化合物含量普遍较高,少数木脂素类成分含量低的干皮样品中,环烯醚萜类成分含量较高。随着树龄的增加,杜仲叶中的黄酮类与苯丙素类成分含量呈减少趋势,木脂素类成分含量呈增加趋势,25年生杜仲叶中木脂素含量最高。杜仲枝皮和干皮中的木脂素类成分含量随着树龄的增加呈增长趋势。在杜仲不同部位中,原儿茶酸的含量随树龄的增加呈增...     

不同变异类型杜仲皮含胶性状的变异规律

为了弄清不同变异类型杜仲皮的生长发育特点及其含胶性状的变异规律,为杜仲胶优良资源的选择和有效利用提供理论依据,进行了本试验研究.试验采用选择典型样株和随机取样的方法;含胶率的测定采用杜仲胶综合提取法.研究结果表明,不同变异类型树皮特征及含胶性状表现出不同的特点.深纵裂型的胸径生长量、树皮厚度和木栓层厚均最大,而光皮型的胸径生长量最小、树皮厚度和木栓层厚最薄;树皮含胶率以浅纵裂型最高,深纵裂型的树皮含胶率最低;树皮内杜仲胶体积质量也以深纵裂型的最高,深纵裂型杜仲胶体积质量最低.     

经济树种杜仲的繁殖

<正> 杜仲育苗有播种、扦插、分株、嫁接等多种方法,生产中以播种育苗法最为实用。根据泗县苗圃多年来繁育经验,现将杜仲播种育苗技术简介如下。1 选用良种 根据树皮特点可将杜仲分为深纵裂型、龟裂型、浅纵裂型、光皮型4个类型,其中光皮型杜仲经济价值较高。我国目前栽培的品种主要为河南省洛阳市林科所选育的华仲1～5号。这5个优良品种生长快、产量     

不同栽培模式对杜仲叶及枝皮中多种活性成分含量的影响

为了探寻不同栽培模式对杜仲叶及枝皮中多种活性成分含量的影响规律,以不同月份采集的吉首大学张家界校区校园内的杜仲矮林与乔林叶片与枝皮为试材,采用高效液相色谱法测定了其绿原酸、京尼平苷酸和松脂醇二葡萄糖苷的含量,采用硝酸铝-亚硝酸钠比色法测定了其总黄酮含量,还用对二甲氨基苯甲醛显色法测定了其桃叶珊瑚苷的含量。测定结果表明:7、9、10月采集的杜仲矮林叶中绿原酸的含量分别为2.416%、2.463%和2.934%,分别是同期采集的杜仲乔林的2.094、1.027和1.968倍;其总黄酮含量分别为1.224%、11.664%和14.564%,分别是杜仲乔林的0.159、0.759和1.146倍;其京尼平苷酸的含量分别为1.404%、1.012%和0.359%,分别是杜仲乔林的0.476、3.819和2.017倍;其桃叶珊瑚苷的含量分别为6.655%、6.543%和6.508%,分别是杜仲乔林的1.623、1.377和1.909倍。11月份采集的杜仲矮林枝皮中京尼平苷酸、桃叶珊瑚苷和松脂醇二葡萄糖苷的含量分别为6.711%、3.494%和0.467%,分别是杜仲乔林的1.035、2.024和1.052倍。测定结果还表明,杜仲矮林叶及枝皮中有多种活性成分的含量高于杜仲乔林,故矮林作业具有推广应用价值。     

杜仲总木脂素及松脂醇二葡萄糖苷的纯化研究

通过大孔吸附树脂-C18反相硅胶柱层析-正相硅胶柱层析联用技术,对杜仲总木脂素及松脂醇二葡萄糖苷(PDG)进行纯化研究。结果表明,含总木脂素23.33%和松脂醇二葡萄糖苷粗品0.960 5%的杜仲提取液经AB-8树脂一次纯化,可以制得71.61%的杜仲总木脂素有效部位以及8.070%的松脂醇二葡萄糖苷粗品,再经C18反相硅胶柱层析纯化,得到53.12%的松脂醇二葡萄糖苷。最后通过正相硅胶柱层析进一步纯化,得到91.50%的松脂醇二葡萄糖苷产品。     

杜仲活性成分与药理研究的新进展

本文介绍了杜仲皮、叶中木脂素类、环烯醚萜类、苯丙素类、其它萜类、多糖类等活性成分的分离与测定技术以及杜仲皮、叶的药理作用研究的新进展；阐述了杜仲叶功能食品及杜仲雄花茶的研究开发现状。     

不同变异类型杜仲果实含胶量变异研究

为弄清不同变异类型杜仲果实含胶特性的变异规律,为杜仲胶优良资源的选择和有效利用提供理论依据,采用典型样株和随机取样的方法;含胶率的测定利用杜仲胶综合提取法。结果表明:4个变异类型的果实形态大小存在极显著差异。不同变异类型在果实形态大小上的不同,表明不同类型生长发育特性的差异;不同变异类型果实含胶率和果皮含胶率均存在极显著差异。果实含胶率和果皮含胶率以浅纵裂型最高,深纵裂型最低。     

杜仲中双环氧木脂素二糖苷分离纯化技术的研究

利用树脂吸附与凝胶色谱柱层析相结合的方法,探讨了杜仲中松脂醇二葡萄糖苷（PG）和丁香脂醇二葡萄糖苷（SG）的分离纯化,并根据HPLC分析结果确定了最佳的分离纯化工艺条件。即当杜仲皮乙醇浸提液经浓缩离心后,在碱性条件下用D101型树脂吸附。粗提物的产率达1．74％,PG和sG的质量分数分别、为8．1397％和2．9431％。经葡聚糖凝胶LH-20,高效液相制备柱的进一步分离及重结晶,得两种结晶。熔点测定、IR、UV、HPLC、TLC及^1H NMR的分析表明,这两种结晶分别为PG（乳白色粉末）和SG（白色针状）。结果表明：树脂吸附与凝胶色谱柱层析相结合制备双环氧木脂素二糖苷提取物的方法与传统分离方法相比,得率高,工艺操作较简单且安全无毒。     

‘华仲12号’杜仲叶片黄酮类物质组成鉴定及含量分析

【目的】了解‘华仲12号’杜仲叶片中黄酮类物质的主要组成,比较分析其与‘华仲11号’杜仲叶片中黄酮类物质在组成和含量的差异情况,为‘华仲12号’杜仲叶片的定向利用研究奠定理论基础。【方法】采用UPLC-PDA-MS/MS法对‘华仲12号’杜仲和‘华仲11号’杜仲叶片提取液中黄酮类物质进行定性和定量检测,并对其组成和含量进行比较分析。【结果】从‘华仲12号’杜仲叶片中共检测到15种黄酮类物质,包括槲皮素糖苷类(10种)、山柰酚糖苷类(3种)和花色苷类(2种)。其中,槲皮素糖苷类的含量最高,为34.644 6 g·kg-1,其含量占检测到的黄酮类物质总含量的94.32%以上;其次为山柰酚糖苷类和花色苷类,其含量分别占检测到的黄酮类物质总含量的4.39%与1.29%。从‘华仲11号’杜仲叶中仅仅检测到槲皮素糖苷类(9种)和山柰酚糖苷类(3种)化合物,其含量分别占检测到的黄酮类物质总含量的88.51%与11.49%。‘华仲12号’杜仲叶中黄酮类物质的总含量为36.732 3 g·kg-1,约为‘华仲11号’杜仲叶中的8.88倍,且‘华仲12号’杜仲叶片中黄酮类物质各组分的含量均明显高于‘华仲1...     

Antibacterial activity of Persea cordata stem barks

The antibacterial effects of extracts obtained from Persea cordata stem bark, employed in Brazil to treat infectious diseases, were studied. The ethyl acetate fraction of the hydroalcoholic extract showed activity against pathogenic bacteria which may justify the popular use of the plant.     

Micromorphology of naturally degraded beech and spruce barks

The micromorphological changes occurring in the bark tissues of beech and spruce trees during natural degradation in the forest have been investigated and compared with those obtained previously using wood-decaying fungi. The relevance of the bark degradation process for the environment is also briefly discussed.     

Antiinflammatory and analgesic activities of Zizyphus lotus root barks

The root barks of Zizyphus lotus were extracted with water, chloroform, ethyl acetate and methanol to determine their antiinflammatory and analgesic activities. Aqueous extract (50, 100 and 200 mg/kg) given intraperitoneally (i.p.) showed a significant and dose-dependent antiinflammatory and analgesic activity.     

Antimicrobial activity of alkaloidal fraction from barks of Himatanthus lancifolius

The alkaloidal fraction from Himatanthus lancifolius barks demonstrated a broad-spectrum in vitro antimicrobial activity for most of the Gram (+) and Gram (-) tested microorganisms.     

Exploitation of polyphenol-rich pine barks for potent antioxidant activity

The phenolic composition of pine bark from a variety of Pinus species was estimated by measuring Klason lignin, acid-soluble lignin, and a 1% NaOH extract. Polyphenol contents of hot water extracts from pine bark were determined by the Folin-Ciocalteu assay and the vanillin-H₂SO₄ assay. Among the pine bark varieties investigated, Pinus radiata bark showed the highest polyphenol content and potent antioxidant activity. Pinus rigida bark was also a usable polyphenol-rich source, whereas Pinus densiflora bark had a low yield (5.1%) of hot water extract, although it showed potent antioxidant activity. Correlations between proanthocyanidin content in pine bark and antioxidant activity were observed. The results suggested that proanthocyanidin was the crucial contributor to potent antioxidant activity in pine bark. The publication of this article was made possible by an Emachu Research Fund. The authors are grateful for the fund.     

Triterpenes of Albizia versicolor and Albizia schimperana stem barks

Several triterpenes were isolated from stem barks of Albizia versicolor and A. schimperana. Spectral data of acacic acid lactone (1) are presented.     

超声波提取杜仲皮总黄酮工艺

以杜仲皮为原料,采用单因素和正交试验,探讨了超声波提取杜仲皮内黄酮的最佳工艺条件。结果表明：采用体积分数95%的乙醇为提取液,杜仲皮与提取液的料液比为1∶40（g∶mL）,每次超声波处理时间为30 min,超声波功率50 W为最佳提取条件,在该条件下黄酮提取率为10.01%。     

Removal of heavy metal ions from solutions by coniferous barks

Summary The abilities of 15 coniferous barks for removing toxic heavy metal ions were investigated. The barks considerably varied in the adsorption ability to each metal ion. Of the barks tested, high adsorption ability for heavy metal ions was found inPicea abies (Norway spruce). Equilibrium experiments usingP. jezoensis (Yezo spruce) bark showed that the adsorption of Cd²⁺ was greatly affected by the pH of solution and the initial Cd²⁺ concentration in solution. The adsorption of Cd²⁺ byP. jezoensis bark followed Freundlich isotherm in the concentration range 10–330 mg Cd²⁺/L. The continuous column experiments usingP. jezoensis bark indicated that the packing had retained 10.1–14.2 mg Cd²⁺/g adsorbent until the column broke through.