两种落叶松树皮中原花色素的快速提取和光谱分析

原花色素的提取通常采取用传统外加热方式的溶剂浸渍法,存在提取时间长、提取效率低等缺点,而微波辅助提取技术具有加热效率高、提取时间短和提取率高等优点,成为传统提取技术的一种替代方式。笔者以兴安落叶松和日本落叶松树皮为研究对象,对比研究了微波辅助提取法和常规水浴浸渍法在不同提取时间下对原花色素提取得率的影响,并利用紫外光谱仪和红外光谱仪对树皮提取物的结构进行了表征。结果表明,和常规浸渍法相比,利用微波辅助提取法可显著缩短提取时间,提高原花色素的提取得率,并且不会引起原花色素结构的破坏。兴安落叶松和日本落叶松树皮中原花色素的微波辅助提取适宜工艺条件为:微波功率200 W,提取时间10 min,温度60℃,溶剂为50%乙醇,溶剂和树皮的体积与质量比(mL∶g)为10∶1。在此条件下,兴安落叶松和日本落叶松树皮中原花色素的提取得率分别为239%和278%。两者树皮中的原花色素均以原花青素结构为主,仅含有少量原翠雀素。相同条件下,兴安落叶松树皮比日本落叶松树皮的原花色素提取得率稍低。微波辅助提取法适用于落叶松树皮中原花色素的提取,是一种快速、有效和安全的方法。     

云南松树皮低聚原花青素的提取工艺的优化试验

以云南松树皮为材料,探讨浸提剂类型、浸提剂体积、浸提时间、料液比对云南松树皮低聚原花青素提取率的影响,通过单因素试验和正交试验,筛选出云南松树皮低聚原花青素提取最佳工艺组合为:浸提时间24 h、浸提剂60%乙醇、料液比1︰8,浸提量达到15.746 mg/g,优选得到的工艺稳定、提取效率高。     

松树皮原花青素的超声提取、超滤膜分离中试研究

通过松树皮原花青素的超声提取、膜分离纯化技术中试试验,考察了超声波提取温度、料液比、提取时间等单因素对原花青素得率的影响,试验得到了超滤膜工作压力、截留分子量的最佳工艺参数。结果表明,采用超声波强化逆流提取松树皮原花青素的最佳参数为：料液比1：12,超声温度60℃,提取时间30min;超滤膜分离纯化工艺参数为：膜工作压力0．2MPa,截留分子量5000。试验获得的松树皮原花青素经检测含量可达95％以上。     

微波法提取西藏芫根多糖的工艺研究

采用单因素试验和正交试验,对微波法提取芫根多糖的工艺进行研究,得到了最佳工艺条件：料液比1∶24,微波处理时间10min,微波功率450W,浸泡时间90min。在此条件下,芫根多糖的提取率为9.13%。试验结果显示微波法与热水浸提法比较,具有提取时间短、提取效率高的优点。     

微波法提取桑叶多糖的工艺条件研究

采用单因素试验和正交试验,对微波法提取桑叶多糖的工艺进行研究,得到了最佳工艺条件：料液比1∶25,溶剂pH值8.0,微波功率300W,微波处理时间10min。在此条件下,桑叶总多糖的提取率为4.26%,较热水浸提法提高了18.99%。试验结果显示微波法与传统提取方法比较,具有提取时间短、提取效率高、节省能源的优点。     

落叶松树皮原花青素的匀浆提取及响应面法优化

采用匀浆法从落叶松树皮中提取原花青素,以得率和纯度为指标,对匀浆提取过程中各因素在单因素试验的基础上采用Box-Behnken试验设计法进行了优化.确定的匀浆提取优化条件为:以体积分数70%乙醇溶液作为提取溶剂,料液比1:15(g:mL),匀浆提取5 min,匀浆提取4次.在此条件下落叶松树皮中原花青素的得率和纯度分别达到17.33%和75.46%.     

不同工艺提取栀子黄色素的比较研究

比较研究了热提取、超声波提取、微波提取3种不同工艺对栀子黄色素提取效果的影响。热浸提正交试验的最佳工艺条件：70％的乙醇（体积分数，下同）提取1．5h，提取温度30℃，料液比1：25（g：mL，下同），产品的色价为66．45。超声波提取正交试验的最佳工艺条件：80％的乙醇提取20min，料液比1：20，产品的色价为87．77。微波提取单因素试验的最佳工艺条件：提取功率800W，用50％乙醇提取30min，提取温度50℃，料液比1：5，色价为64．14。结果表明：热浸提、超声波提取、微波提取3种方法提取栀子黄色素的色价明显不同，超声波提取的效果最好。     

松树皮多酚的亚临界水提取及抗氧化活性初探

采用亚临界水从松树皮中提取多酚,考察了反应条件对多酚得率的影响,并与超声波辅助提取法和热回流提取法进行了比较,同时测定了亚临界水提取所得松树皮提取物的DPPH自由基清除能力.结果表明:亚临界水提取松树皮多酚的最佳工艺条件为:提取温度150℃、提取时间5min、液料比20∶ 1(mL∶g)、提取压力4MPa,多酚的提取得...     

微波辅助提取狗枣猕猴桃黄酮类化合物的研究

狗枣猕猴桃黄酮类化合物含量较多,具有抗发炎、抗病毒、抗氧化、抗癌以及舒张血管等作用及生物活性,而越来越受到人们的重视。主要采用微波辅助提取对狗枣猕猴桃黄酮类化合物提取进行研究,主要的研究结果如下：微波提法最佳提取条件为微波功率455W、微波提取8min,料液比1：20,此条件下可提取0．6070D黄酮类化合物。     

微波辅助法提取滁菊花水溶性成分的试验研究

以微波处理为辅助手段,应用水浴法提取菊花中水溶性成分。对利用微波技术提取菊花水溶性成分的工艺条件进行了研究,通过单因素和正交试验,考察了影响提取得率的因素,得出微波辅助法提取菊花水溶性成分的最佳工艺条件为:料液比1g∶30ml,在微波功率为175W条件下处理时间10min,再在70℃水浴锅中浸提30min,得到总水溶性成分提取得率在43.1%。     

云南切梢小蠹和横坑切梢小蠹对寄主繁殖部位的选择试验(英文)

在室内条件下,对繁殖期云南切梢小蠹和横坑切梢小蠹的竞争展开了研究。在养虫笼中放入来源同株云南松的2根木段,同时放入2种小蠹,分别放入1种小蠹,观察小蠹对其繁殖材料云南松木段的选择。试验表明,横坑切梢小蠹喜在树皮厚的木段上繁殖,即云南松树干的下部,而云南切梢小蠹喜在树皮薄的木段上繁殖,即云南松树干的上部。从产卵到新成虫羽化,云南切梢小蠹的历期明显短于横坑切梢小蠹,分别为86～89 d和120～125 d。结论:在中国云南,云南切梢小蠹对云南松的攻击能力强于横坑切梢小蠹,后者更具次期性害虫特点。     

两种提取红松种子蛋白质的工艺方法比较研究

为寻找新的植物蛋白资源,研究发现,红松种子中蛋白质含量在13％～20％,具有明显的生理活性,是一种新的具有活性的植物蛋白质资源。以脱脂红松种子粉为原料,比较PBS-NaCl缓冲液盐溶法和NaOH碱溶法提取红松种子蛋白质工艺。分别通过单因素和正交试验,确定最佳的提取工艺：研究了料液比、提取温度、提取时间、溶液浓度对蛋白质提取率的影响,并进行了L9（4^5）的正交试验,并测定了两种工艺得到的红松种子蛋白的等电点。PBS-NaCl缓冲液盐溶法得到的红松种子蛋白等电点pI=3．7,碱溶法提取蛋白的等电点pI=4．0。PBS-NaCl缓冲液盐溶法提取红松种子蛋白质的提取工艺：在温度30℃水浴环境下,以0．12mol／LPBS-NaCl缓冲液盐溶液提取,按1：25的料液比搅拌浸提150min,蛋白提取率达到62．86％。碱溶法提取红松种子蛋白质的最佳工艺参数是以0．0005mol／LNaOH溶液,按1：30料液比,在45℃条件下低速搅拌浸提60min,此时蛋白的提取率为72．07％。结论：从蛋白质提取率的角度考虑,碱溶法优于PBS-NaCl缓冲液盐溶法;从蛋白质稳定性和提取率两方面考虑,PBS-NaCl缓冲液盐溶法优于碱溶法。     

超声波辅助提取松仁蛋白的工艺研究

对超声波法辅助提取松仁蛋白的工艺进行了研究，得到了超声波辅提松仁蛋白的最佳工艺条件：液料比10：1，提取时间15min，提取功率900W，在此工艺条件下松仁蛋白提取率为97．645％。此法与常规的碱提酸沉法比较，缩短了很长的提取时间，而且大大提高了蛋白质的提取率。     

Assessing forest vulnerability and the potential distribution of pine beetles under current and future climate scenarios in the Interior West of the US

The aim of our study was to estimate forest vulnerability and potential distribution of three bark beetles (Curculionidae: Scolytinae) under current and projected climate conditions for 2020 and 2050. Our study focused on the mountain pine beetle (Dendroctonus ponderosae), western pine beetle (Dendroctonus brevicomis), and pine engraver (Ipspini). This study was conducted across eight states in the Interior West of the US covering approximately 2.2 million km² and encompassing about 95% of the Rocky Mountains in the contiguous US. Our analyses relied on aerial surveys of bark beetle outbreaks that occurred between 1991 and 2008. Occurrence points for each species were generated within polygons created from the aerial surveys. Current and projected climate scenarios were acquired from the WorldClim database and represented by 19 bioclimatic variables. We used Maxent modeling technique fit with occurrence points and current climate data to model potential beetle distributions and forest vulnerability. Three available climate models, each having two emission scenarios, were modeled independently and results averaged to produce two predictions for 2020 and two predictions for 2050 for each analysis. Environmental parameters defined by current climate models were then used to predict conditions under future climate scenarios, and changes in different species’ ranges were calculated. Our results suggested that the potential distribution for bark beetles under current climate conditions is extensive, which coincides with infestation trends observed in the last decade. Our results predicted that suitable habitats for the mountain pine beetle and pine engraver beetle will stabilize or decrease under future climate conditions, while habitat for the western pine beetle will continue to increase over time. The greatest increase in habitat area was for the western pine beetle, where one climate model predicted a 27% increase by 2050. In contrast, the predicted habitat of the mountain pine beetle from another climate model suggested a decrease in habitat areas as great as 46% by 2050. Generally, 2020 and 2050 models that tested the three climate scenarios independently had similar trends, though one climate scenario for the western pine beetle produced contrasting results. Ranges for all three species of bark beetles shifted considerably geographically suggesting that some host species may become more vulnerable to beetle attack in the future, while others may have a reduced risk over time.     

纵坑切梢小蠹的危险性分析

纵坑切梢小蠹Tomicus piniperda Linn。是我国近年来严重危害松属植物的害虫这一，尤其在云南省造成大面积云南松枯死，危害相当严重。根据其寄主林木的经济价值、危害的严重程度及进一步传播蔓延的可能性等，对其危险性进行了分析与评估。结果表明，纵坑切梢小蠹在我国南方地区属于中度危险的森林有害生物。     

云南松花粉中总黄酮含量的测定

以黄芩甙为标样,对云南松花粉中黄酮类化合物采用甲醇回流提取,用紫外分光光度法进行测定.结果表明破壁云南松花粉中总黄酮含量达到510mg/100g.     

切梢小蠹伴生真菌发生及病害特征的初步研究

小长喙霉 ( Ophiostoma minus Hedgc.)于 190 6年作为新种定名为 Ceratostomella minorHedgc,1981年更名为 Ophiostoma minus Hedgc.,此后一直沿用至今 [1]。小长喙霉以小蠹虫( Tomicus spp.)为媒介 ,通过小蠹虫对树木的蛀害 ,被携带进入到寄主植物组织内 ,进行自身生命过程并危害寄主植物[2 ] ,故也被称为小蠹虫伴生真菌 [3,4] 。该菌的寄主植物主要是松树( Pinus spp.) [4] ,它在协助小蠹虫蛀害松树树木中扮演着重要的角色 [3,4]。80年代以来 ,纵坑切梢小蠹 ( Tomicus piniperda Linnaeus)在云南 8个地州大面积暴发成灾 ,10余万 hm2 …     

Bark beetle-caused mortality in a drought-affected ponderosa pine landscape in Arizona,USA

Extensive ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality associated with a widespread severe drought and increased bark beetle (Coleoptera: Curculionidae, Scolytinae) populations occurred in Arizona from 2001 to 2004. A complex of Ips beetles including: the Arizona fivespined ips, Ips lecontei Swaine, the pine engraver beetle, Ips pini (Say), Ips calligraphus (Germar), Ips latidens (LeConte), Ips knausi Swaine and Ips integer (Eichhoff) were the primary bark beetle species associated with ponderosa pine mortality. In this study we examine stand conditions and physiographic factors associated with bark beetle-caused tree mortality in ponderosa pine forests across five National Forests in Arizona. A total of 633 fixed-radius plots were established across five National Forests in Arizona: Apache-Sitgreaves, Coconino, Kaibab, Prescott, and Tonto. Prior to the bark beetle outbreak, plots with mortality had higher tree and stocking compared with plots without pine mortality. Logistic regression modeling found that probability of ponderosa pine mortality caused by bark beetles was positively correlated with tree density and inversely related with elevation and tree diameter. Given the large geographical extent of this study resulting logistic models to estimate the likelihood of bark beetle attack should have wide applicability across similar ponderosa pine forests across the Southwest. This is particularly true of a model driven by tree density and elevation constructed by combining all forests. Tree mortality resulted in significant reductions in basal area, tree density, stand density index, and mean tree diameter for ponderosa pine and for all species combined in these forests. Most of the observed pine mortality was in the 10–35 cm diameter class, which comprise much of the increase in tree density over the past century as a result of fire suppression and grazing practices. Ecological implications of tree mortality are discussed.     

火炬松松针多糖提取工艺及其抗氧化性研究

以多糖得率为指标,从火炬松松针中浸提多糖,并测定其体外抗氧化活性。在单因素试验基础上采用响应面法优化超声波辅助热水浸提火炬松松针多糖,最佳的工艺参数为:30 g松针粉末在超声波作用时间25 min,热水浸提1 h,液料比25∶1(m L∶g),热水浸提温度91℃。在此条件下,火炬松松针多糖得率达1.867%,提取率达91.39%。通过测定松针多糖对苯基苦基肼自由基(DPPH·)、羟基自由基(·OH)和2,2-联氮-二-(3-乙基-苯并噻唑-6-磺酸)自由基(ABTS+)的清除能力评价其体外抗氧化能力。结果显示:火炬松松针多糖对自由基DPPH·、·OH和ABTS+都有较强清除能力,且都呈较好的量效关系,火炬松松针多糖具有较强的体外抗氧化能力。