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贵州矮杨梅叶总黄酮的提取工艺和测定方法 总被引：1，自引：0，他引：1
目的:建立矮杨梅叶总黄酮的提取工艺和含量测定方法。方法:利用L9(34)进行矮杨梅叶总黄酮提取影响因素即乙醇浓度、提取时间、料液比的优化组合;应用分光光度计考察其含量测定方法。结果:矮杨梅叶总黄酮的提取工艺为提取时间为1.5h,乙醇浓度为50%,材液比为1:35,提取率为4.88%;总黄酮提取液在0-60min内测定,线性关系良好(0.9996),仪器较为稳定,测定结果准确、重现性好,回收率高。结论:矮杨梅叶总黄酮的提取工艺可行、测定方法可信。这一研究结果对于杨梅属植物中总黄酮的提取和测定具有可操作性和推广应用价值。 相似文献
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Dried ground leaves ofPsidium guajava L. (guava) were extracted by water and aqueous ethyl alcohol 50% (1∶10) ratio, and the total phenolic content in the extracts
was determined spectrophotometrically according to Folin-Ciocalteu's phenol method and calculated as gallic acid equivalent
(GAE). Remarkably high total phenolic content 575.3±15.5 and 511.6±6.2 mg of GAE/g of dried weight material (for ethanol guava
leaf extracts and water guava leaf extracts, respectively) were obtained. The antioxidant activity of lyophilized extracts
was determined at ambient temperature by means of a 2,2-diphenyl-1-picrylhydryzyl (DPPH') colorimetry with detection scheme
at 515 nm. The activity was evaluated by the decrease in absorbance as the result of DPPH' color change from purple to yellow.
The higher the sample concentration used, the stronger was the free radical-scavenging effect. The results obtained showed
that ascorbic acid was a substantially more powerful antioxidant than the extracts from guava leaf. On the other hand, the
commercial guava leaf extracts and ethanol guava leaf extracts showed almost the same antioxidant power whereas water guava
leaf extracts showed lower antioxidant activity. The parameter EC50 and the time needed to reach the steady state to EC50 concentration (T
EC
50) affected the antiradical capacity of the sample. The antioxidant efficiency (AE) has been shown to be a more adequate parameter
for selecting antioxidants than the widely used EC50. This study revealed that guava leaf extracts comprise effective potential source of natural antioxidants. 相似文献
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Haider Samee Zhen-xing Li Hong Lin Jamil Khalid Yong-chao Guo 《Journal of Zhejiang University. Science. B》2009,10(2):147-153
Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities.They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan,and Sargassum graminifolium turn (SG),Sargassum thunbergii (STH),and Laminariajaponica (LJ) from China.The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin,an inhibitor against hyaluronidase.Total phlorotannins contained in the crude extracts were measured as 1.71% (SG),0.74% (STH),0.97% (LJ),3.30% (SC),and 5.06% (ST).The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml,respectively,lower than those of Chinese SG,STH,and LJ (134,269,and 148 μg/ml,respectively).An antiallergic drug,disodium cromoglycate (DSCG),had an IC50=39 μg/ml,and a natural inhibitor of hyaluronidase,catechin,had an IC50=20 μg/ml.The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml).This suggests that ST is a potent inhibitor of hyaluronidase,indicating a promising future development of natural antiallergic medicines or functional foods. 相似文献
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以漳州血柚皮为原料,采用超声波辅助提取法,以乙醇为提取溶剂提取并测定总黄酮含量,分别对乙醇浓度、超声温度、超声功率、料液比、超声时间进行单因素和正交试验,并通过极差、方差及多重比较对提取过程显著影响提取率的因素进行统计分析.结果表明,固定超声时间为20 min 时,血柚皮超声波提取法的最佳工艺条件为:乙醇浓度为55%,超声温度为55℃,超声功率为200 W,料液比为1:20,该工艺条件下血柚皮总黄酮的提取率为1.41%,该工艺提取效率高、提取时间短,操作简单且结果稳定 相似文献
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目的：优选鸡血藤总黄酮提取的最佳工艺条件。方法：利用紫外分光光度法测定总黄酮的含量,以鸡血藤总黄酮含量作为评价指标,采用U（94）均匀设计表设计试验,观察与分析提取剂浓度、提取时间、料液比、颗粒度4种因素对鸡血藤总黄酮提取的影响。结果：提取鸡血藤总黄酮最佳状态是：60％的乙醇,鸡血藤粉碎程度50目,液料比为40：1,提取药材时间2.5小时,结论：本工艺操作简便合理,结果稳定可靠,重复性好,具有可行性,可推广应用。 相似文献
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为探讨微波法提取沙溪蜜柚废弃物中黄酮的提取工艺,以沙溪蜜柚柚皮为原料,考查了微波功率、提取时间、乙醇浓度、料液比对黄酮提取率的影响．通过L9（3^4）正交设计试验优化出最佳提取工艺条件为：微波辐射功率为250W,辐射时间2min,乙醇浓度70％,料液比1：70．在最优条件下黄酮的提取率为0．272％． 相似文献
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采用正交试验L9（3^4）,对加热回流提取和超声提取优化广东紫珠总黄酮的提取工艺进行了比较研究.以提取物中总黄酮得率为评价指标,利用紫外分光光度法测定黄酮的含量.结果表明,加热回流提取的最佳工艺条件为A1 B3 C2,即乙醇浓度为60％、水浴温度为80℃、提取时间为2 h;超声法为A2 B1 C2,即乙醇浓度为70％、固液比为1：20、超声40 min.芦丁对照品9.4～75.2μg·mL^1范围内与吸光度呈良好的线性关系.加热回流提取法优于超声法,黄酮提取率达到9.27％. 相似文献
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竹叶总黄酮提取工艺研究 总被引：1，自引：1，他引：0
探讨用醇提法提取竹叶中黄酮类成分的最佳工艺,为竹叶的开发利用提供理论依据。以竹叶为试材,以乙醇为溶剂,采用分光光度法对竹叶中的黄酮类化合物的含量进行测试。通过单因素实验研究乙醇浓度、料液比、提取温度、提取时间对总黄酮提取率的影响,再采用正交试验法优化提取总黄酮的最佳工艺条件。单因素实验和正交试验表明:影响黄酮提取率的因素主次顺序是:料液比>乙醇浓度>提取温度>提取时间。最佳实验条件为料液比1:20,60%的乙醇,60℃提取4h,竹叶中黄酮的含量为7.88mg.g-1。 相似文献
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采用正交试验法优化都匀楼梯草中总黄酮的超声波提取工艺,考察超声波作用时间、乙醇浓度和液料比3个因素对都匀楼梯草总黄酮提取率的影响,确定都匀楼梯草总黄酮的优化超声波提取工艺条件为：提取溶剂80％乙醇,料液比1∶25,超声波作用时间40 min,最佳提取率为1.62％.乙醇提取物抑制DPPH自由基的能力IC50=125.25μg/mL,说明都匀楼梯草不同极性部位均具有一定的抗氧化活性. 相似文献
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采用超声波法从茉莉花中提取黄酮类化合物并得出最佳提取条件,物料比为1∶25,80％乙醇做溶剂,超声提取时间为50min时黄酮提取率较高.用紫外光谱法测定黄酮化合物的含量,芦丁标准溶液线性回归方程为A=0.9561C-0.0051,相关系数r=0.9990,此方法的回收率为98％～100％,变异系数0.015％,方法快速,准确度与精密度均较高. 相似文献
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响应面法优化兰香草总黄酮超声提取工艺 总被引：1，自引：0，他引：1
采用NaNO2-Al(NO3)3-NaOH体系分光光度法,测定吸光度,比较不同条件下兰香草总黄酮提取率;在单因素试验的基础上利用响应面法对提取工艺进行优化设计;通过Plackett-Burman软件对试验因素进行筛选;应用Design Expert 7.0软件对试验因素进行中心组合设计,并将实验结果进行回归分析。结果表明,乙醇浓度、液料比、提取时间为影响兰香草总黄酮提取率的主要因素;试验所得模型与试验数据拟合度较高,可用来预测不同提取条件下的兰香草总黄酮得率;由回归方程求得的最佳提取工艺为在40℃温度下,用73%乙醇为溶剂,控制液料比为45 mL·g-1,提取32 min。 相似文献
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采用微波法辅助提取苦参总黄酮,以乙醇体积分数、提取时间、液料比及微波功率为自变量,苦参总黄酮提取率为评价指标,采用Box-Behnken试验设计及响应面法分析优化提取工艺条件.结果表明,最优提取工艺为乙醇体积分数80％,提取时间6min,液料比25：1（mL/g）,微波功率400W.在此条件下,黄酮提取量达到12.67mg/g. 相似文献
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辽宁苦菜中总黄酮含量及抗氧化性能分析 总被引：1，自引：0，他引：1
对辽宁苦菜中总黄酮的含量和抗氧化性能进行研究.采用索氏提取法,以70%乙醇溶液为提取溶剂对苦菜中的黄酮类化合物进行提取,通过光谱分析法测定其含量,并利用流动注射化学发光法测定其抗氧化性能.结果表明辽宁苦菜中总黄酮的含量为88.18 mg/g,苦菜总黄酮抗氧化的IC50为0.62 mg/mL,由此说明辽宁苦菜中总黄酮的含量较高,且具有较强的抗氧化性能. 相似文献
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Different responses of two Mosla species to potassium limitation in relation to acid rain deposition
Meng Wang Bao-jing Gu Ying Ge Zhen Liu De-an Jiang Scott X. Chang Jie Chang 《Journal of Zhejiang University. Science. B》2009,10(8):563-571
The increasingly serious problem of acid rain is leading to increased potassium (K) loss from soils, and in our field investigation,
we found that even congenerically relative Mosla species show different tolerance to K-deficiency. A hydroponic study was conducted on the growth of two Mosla species and their morphological, physiological and stoichiometric traits in response to limited (0.35 mmol K/L), normal (3.25
mmol K/L) and excessive (6.50 mmol K/L) K concentrations. Mosla hangchowensis is an endangered plant, whereas Mosla dianthera a widespread weed. In the case of M. hangchowensis, in comparison with normal K concentration, K-limitation induced a significant reduction in net photosynthetic rate (P
n), soluble protein content, and superoxide dismutase (SOD) activity, but an increase in malondialdehyde (MDA) concentration.
However, leaf mass ratio (LMR) and root mass ratio (RMR) were changed little by K-limitation. In contrast, for M. dianthera, K-limitation had little effect on P
n, soluble protein content, SOD activity, and MDA concentration, but increased LMR and RMR. Critical values of N (nitrogen):
K and K:P (phosphorus) ratios in the shoots indicated that limitation in acquiring K occurred under K-limited conditions for
M. hangchowensis but not for M. dianthera. We found that low K content in natural habitats was a restrictive factor in the growth and distribution of M. hangchowensis, and soil K-deficiency caused by acid rain worsened the situation of M. hangchowensis, while M. dianthera could well acclimate to the increasing K-deficiency. We suggest that controlling the acid rain and applying K fertilizers
may be an effective way to rescue the endangered M. hangchowensis.
Project supported by the National Natural Science Foundation of China (No. 30570113) and the Research Fund for the Doctoral
Program of Higher Education (No. 20060335008), China 相似文献
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Based on the laboratory experiments with the saltwater and freshwater replacing each other in the level sand column, taking
the kaolin, illite, smectite, bivalent hydrargyrum ion (Hg2+) and phenol (C6H5OH) as examples, this paper studies the applications of water sensitivity in situ remediation in saltwater-freshwater transition zone. In the water sensitivity process, the release and migration of clay
minerals can make the hydraulic conductivity (HC) decrease and pollutants remove. A new type of low penetrable or impenetrable
purdah can be built by adding clay minerals into the sand media to replace the underground concrete impenetrable wall to prevent
seawater intrusion, and a number of the heavy metals and organic pollutants in the sand media can be removed by in situ remediation. The results show that the content of kaolin and illite influences the water sensitivity process slightly, and
HC of the sand columns descends from 0.011 cm/s to 0.001 4 cm/s and 0.001 2 cm/s respectively even if the content reaches
12% (weight ratio, sic passim). However, for smectite, HC descends sharply to about 1×10−8 cm/s when its content reaches 4%, and no water can flow through the sand columns beyond 5%. The particle release and migration
processes can remove the Hg2+ and C6H5OH out of the sand columns efficiently, the removing rate of Hg2+ is 31.68% when the freshwater and saltwater are filtered through the sand columns polluted by Hg2+, while it is 67.55% when the water sensitivity occurs. With the same method, the removing rates of C6H5OH under the fluid flow and water sensitivity are 55.71% and 43.43% respectively.
Supported by National Natural Science Foundation of China (No. 40572142).
HAN Zhiyong, born in 1976, male, Dr, associate Prof. 相似文献