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1.
茶树花多酚大孔树脂纯化工艺研究   总被引:4,自引:0,他引:4  
该文以废弃茶树花为原料,采用超滤法处理茶树花多酚超声波辅助乙醇浸提液,去除大分子物质,运用静态吸附和动态吸附试验对HZ系列5种大孔吸附树脂及其纯化茶树花多酚工艺条件进行筛选,采用HPLC监测树脂纯化前后茶树花多酚的变化情况。结果表明,HZ-806大孔吸附树脂对茶树花多酚的吸附性能与解吸效果最好,吸附率和解吸率分别达到97.5%、98.20%,适宜作为茶树花多酚纯化的树脂;HZ-806大孔树脂纯化茶树花多酚的工艺条件为:上柱液pH 3.0,上柱液浓度4.0 mg/mL,上柱液体积6 BV,上柱流速4 BV/h,洗脱液乙醇浓度70%,洗脱流速2 BV/h,洗脱体积3.33 BV;采用上述纯化工艺茶树花多酚纯度从19.43%提高到84.32%。  相似文献   

2.
鱼腥草叶总黄酮的提取分离   总被引:3,自引:0,他引:3  
采用微波辅助提取鱼腥草叶总黄酮,并用正交试验进行工艺参数的优化。同时选择7种大孔树脂,比较其对鱼腥草叶总黄酮的吸附量和解吸率,筛选出较优的大孔树脂并对其动态吸附及解吸性能进行考察。结果表明:优化的工艺条件为乙醇浓度50%,固液比1∶50(w/v),预浸泡30 min,微波作用时间30 s,微波功率540 W;与传统乙醇提取法相比,微波法使每次提取时间由3 h减少为30.5 min,提取率从92.14%增加到95.93%。NKA-9型大孔树脂对鱼腥草叶总黄酮有较好的吸附和解吸效果;较优的吸附分离工艺参数为:样液pH值在3.00~3.50,上样液流速1 mL/min,上样液浓度2.21~3.10 mg/mL,用70%乙醇洗脱时,解吸率达97.8%,3BV洗脱液基本上能将鱼腥草叶总黄酮洗脱下来。  相似文献   

3.
新郑灰枣富含各种营养成分,特别是多糖具有抗氧化抗癌等许多生物效应。为研究新郑灰枣多糖的提纯工艺,该文在超声波酶法联合提取、乙醇沉淀、超滤膜过滤得到的粗多糖的基础上,筛选出的AB-8大孔树脂纯化多糖,并对树脂的动态吸附解吸特性进行研究。响应曲面法优化AB-8大孔树脂动态吸附工艺条件,最佳动态吸附条件为:上样速率1.5mL/min,料液浓度2.2mg/mL,pH值5.6,最大动态吸附量为19.52mg/g;正交试验优化AB-8大孔树脂动态解吸的最佳工艺条件为:氯化钠浓度为0.4mol/L,乙醇添加量60%,盐酸浓度0.2mol/L,流速1.5mL/min,最优动态解吸率为85.21%。通过树脂纯化,多糖纯度可达88.87%。该红枣多糖提纯技术是一种非常有效的方法,在医疗及保健行业具有巨大的应用潜力和市场。  相似文献   

4.
大孔树脂对苹果渣中多酚物质的吸附研究   总被引:16,自引:3,他引:16  
通过静态吸附与解吸实验对8种大孔树脂进行筛选,结果表明:NKA-9型大孔树脂表现出最好的吸附性能与解吸效果,是较好的富集纯化苹果多酚树脂。通过单因素实验,确定NKA-9树脂的较佳动态吸附条件为苹果多酚液浓度2.50 mg/mL,pH 4.5,流速1.0 mL/min,较佳洗脱条件为乙醇浓度60%,洗脱流速1.0 mL/min,洗脱体积10 BV。  相似文献   

5.
为了分离苹果汁中的果酸,该文对离子交换法分离浓缩苹果汁中果酸的技术方法进行了系统研究,通过树脂分离果酸的静态和动态试验,对离子交换树脂进行了筛选优化,对树脂洗脱剂和洗脱条件进行了优选与优化,结果表明:D380树脂对果酸的交换吸附能力最强,其静态吸附量为30.73 mg/mL,动态吸附量可达60.24 mg/mL,静态交换吸附平衡时间为270 min,最佳吸附果汁浓度为11°Brix苹果汁;D380树脂对果酸的较佳动态吸附条件为:流速5 mL/min,温度20℃,果汁浓度11°Brix的苹果汁;较佳洗脱条件为:50%乙醇,温度25℃,流速6 mL/min,洗脱3次,洗脱剂与树脂比例2∶1(v/v)。  相似文献   

6.
黑青稞麸皮结合态酚类物质大孔树脂分离纯化工艺优化   总被引:2,自引:2,他引:0  
为了筛选对黑青稞麸皮结合酚类物质具有良好吸附、解吸性能的树脂,并建立其分离纯化工艺,评价其体外抗氧化活性,提高黑青稞麸皮的加工利用价值。本研究通过静态吸附和解吸试验比较了10种大孔树脂对黑青稞麸皮结合酚中总酚和总黄酮的分离纯化效果,筛选出AB-8为最佳吸附树脂类型,其静态吸附4 h可达到饱和;优化的吸附和解吸工艺参数为:黑青稞麸皮结合酚提取液pH值为3.0,上样质量浓度1.5 mg/mL,上样速度为1.5 mL/min,60%乙醇溶液作为洗脱剂进行动态洗脱,洗脱流速为1.5 mL/min;优化工艺条件下,经LC/MS检测,AB-8大孔树脂能显著提高71.43%以上不同种类单体酚的含量,且阿魏酸、丁香酸、苯甲酸、鞣花酸、杨梅素和芦丁是纯化后黑青稞麸皮结合酚中的主要酚类物质;体外抗氧化活性表明,黑青稞麸皮结合酚粗提物和纯化物均具有较强的体外抗氧化活性,纯化后的黑青稞麸皮结合酚溶液清除DPPH·、ABTS·+自由基及FRAP铁离子还原能力均显著增强。研究结果表明AB-8大孔树脂对黑青稞麸皮结合酚中总酚和总黄酮有较好的分离纯化效果,具有潜在的工业应用前景。  相似文献   

7.
大孔吸附树脂分离纯化红小豆多酚工艺及效果   总被引:1,自引:4,他引:1  
为开发利用红小豆加工副产物中的生理活性物质,该研究采用大孔树脂吸附法对煮制红小豆水的多酚类物质进行分离纯化,比较了5种不同型号大孔树脂对红小豆多酚的吸附分离效果,从中筛选出HPD 600型树脂作为理想的吸附剂;研究了 HPD 600树脂对红小豆多酚的吸附等温线,结果表明,该吸附等温线与 Langmuir、Freundlich函数曲线的拟合程度非常高,且采用Langmuir模型的拟合效果略优于Freundlich模型。静态和动态吸附、洗脱试验结果表明:样品液浓度、温度、pH值、乙醇浓度、上样流速及洗脱流速等因素均对HPD 600树脂吸附分离红小豆多酚有影响。较理想的工艺参数为:30℃是较适宜的静态吸附温度;保持煮制红小豆水本身的多酚浓度0.96 mg/mL和pH值6.8,上样体积200 mL,上样流速1.0 mL/min进行动态吸附;吸附饱和平衡后,采用50 mL 60%乙醇溶液,以1.5 mL/min的流速进行动态洗脱。依此得到的红小豆多酚纯化液,其总酚含量和总抗氧化能力均有显著提高,约为纯化前的2.2倍。  相似文献   

8.
大孔树脂精制苦荞总黄酮工艺条件的优化研究   总被引:3,自引:3,他引:3  
为了研究DM-2型大孔树脂精制苦荞总黄酮的优化工艺条件,以树脂对苦荞总黄酮的吸附率、解吸率为评价指标,采用响应曲面法(response surface methodology,RSM)建立树脂法精制苦荞总黄酮的二次多项回归模型方程,对精制苦荞总黄酮吸附解吸工艺条件进行优化。结果表明吸附最佳工艺条件为吸附速率2 mL/min,pH值2,上样液浓度2 mg/mL。解吸最佳工艺条件:乙醇浓度71.05%,pH值8.76,解吸速率1 mL/min。该方法简单可行,精制效果好,适合于工业化生产。  相似文献   

9.
微波辅助萃取-大孔树脂分离纯化芳樟叶黄酮   总被引:1,自引:0,他引:1  
为了综合利用芳樟叶精油提取过程中产生的大量残渣,该文利用微波辅助萃取和大孔树脂选择性吸附来分离纯化芳樟叶黄酮。采用L9(34)正交试验,考察了萃取剂、微波辐射功率、辐射时间及料液比对黄酮得率的影响,确定了微波辅助萃取的优化工艺条件:以60%乙醇做萃取剂,微波功率320W,间歇辐射2次,每次1min,料液质量体积比1:12,在此条件下,芳樟叶黄酮的提取得率为2.97%,与乙醇热回流提取方法相比,得率提高了6.83%,时间缩短了98.89%;为进一步纯化萃取所得的黄酮提取物,选择6种大孔吸附树脂,测定芳樟叶黄酮在树脂上的吸附量和解吸率,筛选出了吸附剂HPD-450,其对芳樟叶黄酮有较好的静态吸附和解吸效果。经装填有大孔树脂HPD-450的固定床纯化后黄酮纯度由22.49%提高到51.28%,纯化倍数2.3倍。  相似文献   

10.
芹菜黄酮在LSA-10树脂上的吸附特性   总被引:1,自引:1,他引:1  
为了分离、纯化芹菜黄酮,比较了8种大孔树脂的静态吸附过程,筛选出了适合吸附芹菜黄酮的树脂;研究了芹菜黄酮在大孔吸附树脂上的动态吸附特性,并确定分离芹菜黄酮的适宜工艺条件.结果表明:LSA-10大孔吸附树脂对芹菜黄酮有较好的吸附分离性能,其对芹菜黄酮的静态吸附平衡时间为4 h;20℃时LSA-10树脂的吸附过程可用Langmuir吸附等温式来描述,吸附溶液适宜的pH值为5.0.操作流速、芹菜黄酮浓度、温度等工艺条件对LSA-10树脂的动态吸附动力学曲线都有影响:确定树脂柱的较佳操作条件为:流速1.0 mL/min,芹菜黄酮浓度0.4 mg/mL,温度20℃.  相似文献   

11.
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

14.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

15.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

16.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

17.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

18.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

19.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

20.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

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