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1.
真眼点藻类色素的提取与测定方法   总被引:1,自引:0,他引:1  
分别采用甲醇、乙醇和丙酮3种有机溶剂提取7种真眼点藻的色素,比较3种有机溶剂提取色素的效果,测定3种有机溶剂色素提取液的吸收光谱,利用分光光度法计算藻的叶绿素a和类胡萝卜素的含量,并比较甲醇和乙醇色素提取液在A470和A666的最大吸收峰。结果表明:使用乙醇比甲醇和90%丙酮操作更简便、快捷并且毒害低。3种有机溶剂色素提取液的叶绿素a和类胡萝卜素的含量均无显著性差异(P>0.05),提取率基本一致。色素在3种有机溶剂中的吸收光谱相似,甲醇和乙醇的色素提取液在A470和A666的最大吸收峰并无显著性差异(P>0.05)。乙醇色素提取液可使用Lichtenthaler的公式计算色素含量。  相似文献   

2.
Three spectrophotometric methods for the quantitative determination of different flavonoid groups and total phenolics in Croatian propolis samples were optimised and validated. The assay based on the formation of aluminium chloride complex (with galangin as a standard) was applied to the quantification of flavones and flavonols, while the 2,4-dinitrophenylhydrazine method (with pinocembrine as a reference) was used for the quantification of flavanones. Total phenolic content was measured by the Folin-Ciocalteau method using reference solution of caffeic acid:galangin:pinocembrine (1:1:1). Through analytical validation, the most suitable extraction conditions (with respect to time, temperature and concentration of extraction solvent) were determined, and final conditions for the extraction were established (80% ethanol, 1 h at the room temperature). The appropriate ratio between the mass of raw propolis and the extraction solvent volume was also established. By the application of the optimised method of extraction, 10 propolis tinctures were prepared and subjected to the analysis of general pharmacopoeial parameters, which are fundamental for the creation of quality specification (relative density, dry residue of extract, content of ethanol, methanol and 2-propanol). Additionally, the content of waxes as the main inactive constituents was determined in order to observe the level of their migration from crude propolis to the prepared tinctures.  相似文献   

3.
赵亮  曹红 《生物磁学》2011,(14):2759-2766,2774
目的:优化白芷中药材有效成分的提取工艺;全面系统地考察与研究市场上白芷中药材的质量。方法:以白芷中欧前胡素和异欧前胡素的含量为指标,采用高效液相色谱法测定,利用正交试验,对渗漉法提取白芷有效成分的工艺条件进行优选;按照《中国药典》2005年版一部白芷项下[含量测定]方法检验了62批次市场上销售的白芷药材中香豆素类物质的含量。结果:乙醇渗漉提取法:药材浸泡24h,加80%乙醇8倍量渗漉,欧前胡素和异欧前胡素的平均提取率为78%;市场上销售的白芷药材中香豆素类物质的含量符合药典的要求。结论:应用渗漉法工艺提取白芷中药材有效成分效率高,稳定性好,适合工业化生产;目前市场上流通的白芷中药材的质量可靠。  相似文献   

4.
正交试验优化梓醇的微波辅助提取工艺   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:通过正交实验优选了地黄中梓醇的微波提取工艺。方法:以地黄粗提液中梓醇含量为指标,HPLC为含量测定方法,采用正交实验法,选取乙醇浓度(A)、料液比(B)、提取时间(C)和提取次数(D)4个因素,每个因素选取3个水平进行实验,确定了最佳提取工艺。结果:研究结果表明乙醇浓度为60%,料液比为4,微波提取3次,每次3 min为梓醇的最佳提取工艺。结论:微波辅助提取地黄中梓醇效率高,提取完全,方法可行。  相似文献   

5.
Two solvent extraction procedures were used to investigate the extraction efficiency in terms of total antioxidant capacity and total phenols in apricot fruit. Samples were either sequentially extracted with aqueous ethanol (ethanol/water 80% v/v) and tetrahydrofuran or directly extracted with tetrahydrofuran. Each extract was analyzed for total antioxidant capacity by the Trolox Equivalent Antioxidant Capacity (TEAC) assay and total phenols by the Folin-Ciocalteu assay. The results showed that using sequential solvent extraction, the majority (85%) of the total antioxidant capacity and total phenols was due to hydrophilic compounds. In tetrahydrofuran direct extractions, the total antioxidant capacity and total phenols were higher than values obtained with aqueous ethanol and the sum of results obtained from sequential extracts for either total antioxidant capacity or total phenols was similar to the tetrahydrofuran-extract antioxidant values. A linear correlation between total antioxidant capacity and total phenols was found and was independent of the solvent extraction method. In conclusion, the choice of solvent is related to the antioxidant potential of fruit and depends on the food hydrophilic/lipophilic composition.  相似文献   

6.
Althaea officinalis (Malvaceae) is a well-known plant that is widely distributed throughout the world. Aqueous and hydroalcoholic extracts from A. officinalis root are used mainly because of their antitussive and expectorant activity. It is well known that these activities are based on the polysaccharide composition, but little is known about the possible antioxidant activity of root extract. The present study evaluated antioxidant activity of root extracts prepared with different extraction solvents applying ABTS·+ (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), hypochlorous acid scavenging assay and iron-induced lipid peroxidation. The results showed that the extract prepared with water as extraction solvent did not possess antioxidant activity, whereas the extracts obtained using ethanol:water as extraction agent showed well pronounced antioxidant activity. In particular, the extracts obtained at low concentration of ethanol in the mixed solvent (50:50 and 70:30, v/v) showed higher scavenging activity for ABTS·+ radicals and hypochlorite ions than the extract obtained with the higher ethanol concentration (90:10, v/v). These results correlated very well with phenolic and flavonoid content of the extracts. The extracts did not show cytotoxic effect on human BV-173 leukemic cells but may have immunomodulating effects due to their antioxidant properties.  相似文献   

7.
通过比较白桦树皮中白桦脂醇的不同的提取方法,获得一种简单、高效的白桦脂醇提取、纯化方法。通过对不同浸提时间比较、超声震荡方法及旋转蒸发仪回收提取3种白桦脂醇提取方案的比较,进一步利用甲醇-氯仿重结晶法、无水乙醇重结晶法及大孔吸附树脂层析法对获得的白桦脂醇初提取物进行纯化。获得了白桦脂醇提取及纯化的最佳方案。用95%乙醇溶液,液固比50∶1(mL∶g)浸泡白桦树皮样品120 h后,用滤纸过滤,收集滤液,将滤液50℃加热回流5 h,减压蒸馏得到米白色固体粉末。接着以70 mL乙酸乙酯为溶剂,将得到的固体加热回流90 min,趁热过滤。滤液使用坩埚50℃浓缩至干。再以无水乙醇为溶剂进行重结晶,无水乙醇∶固体=30 mL∶1 g,-20℃重结晶,重结晶产率可达38.00%,最高纯度达到99.81%。优化后的白桦脂醇提取纯化方法操作简便,产量较高、试剂安全,是一种可用于规模化提取的有效方法。  相似文献   

8.
A solvent recycling reflux extraction process for Panax notoginseng was optimized using a design space approach to improve the batch-to-batch consistency of the extract. Saponin yields, total saponin purity, and pigment yield were defined as the process critical quality attributes (CQAs). Ethanol content, extraction time, and the ratio of the recycling ethanol flow rate and initial solvent volume in the extraction tank (RES) were identified as the critical process parameters (CPPs) via quantitative risk assessment. Box-Behnken design experiments were performed. Quadratic models between CPPs and process CQAs were developed, with determination coefficients higher than 0.88. As the ethanol concentration decreases, saponin yields first increase and then decrease. A longer extraction time leads to higher yields of the ginsenosides Rb1 and Rd. The total saponin purity increases as the ethanol concentration increases. The pigment yield increases as the ethanol concentration decreases or extraction time increases. The design space was calculated using a Monte-Carlo simulation method with an acceptable probability of 0.90. Normal operation ranges to attain process CQA criteria with a probability of more than 0.914 are recommended as follows: ethanol content of 79–82%, extraction time of 6.1–7.1 h, and RES of 0.039–0.040 min−1. Most of the results of the verification experiments agreed well with the predictions. The verification experiment results showed that the selection of proper operating ethanol content, extraction time, and RES within the design space can ensure that the CQA criteria are met.  相似文献   

9.
超临界流体萃取——高效液相色谱法测定百合中秋水仙碱   总被引:9,自引:0,他引:9  
分别用超临界二氧化碳流体和有机溶剂萃取百合中的秋水仙碱,然后用高效液相色谱法直接测定萃取物中秋水仙碱的含量,从而测得百合中秋水仙碱的含量。超临界流体萃取的条件是:用乙醇作提携剂,萃取压力为18MPa,萃取温度为40℃,高效液相色谱测定条件为:ODS柱,甲醇:磷酸二氢钾溶液作流动相,检测波长为220nm,此法快速,简便,准确,可应用于秋水仙碱原料,制剂及其它植物中秋水仙碱含量的测定。  相似文献   

10.
盾叶薯蓣总皂苷超声提取及动力学   总被引:3,自引:0,他引:3  
考察了乙醇体积分数、溶剂用量、超声时间、超声功率和超声频率对盾叶薯蓣总皂苷提取率的影响,研究了以体积分数70%乙醇溶液或水作溶剂从盾叶薯蓣中超声提取总皂苷的动力学模型。结果表明,在扩散过程中超声提取薯蓣总皂苷的动力学模型满足非定常扩散方程,相关系数为r=0.95,最佳超声时间为40min。  相似文献   

11.
Elimination of ethanol inhibition by perstraction   总被引:2,自引:0,他引:2  
Perstraction (membrane-aided solvent extraction) was utilized for elimination of ethanol inhibition in continuous ethanol fermentation using high sugar concentrate. Hollow fibers for an artificial kidney were used as a permeable membrane, and their capacity to extract ethanol was examined by using several organic solvents. When tri-n-butylphosphate was used as an extractant, a 500 g/L feed glucose medium was successfully fermented by immobilized yeast cells. During this continuous fermentation a high ehtanol productivity of 48 g/h-L-gel was held, and the solvent requirement per consumed glucose was 6 L-solvent/kg-glucose.  相似文献   

12.
A dipping method was developed to extract the catechins (EGCG) and alkaloids (caffeine) from green tea (Korea) and black tea (Sri Lanka). The effects of the solvent composition (water vs. ethanol), extraction time, temperatures, and solvent pH on the amount of catechins (EGCG) and alkaloids (caffeine) extracted from green and black tea were investigated. Reversedphase high-performance liquid chromatography (RP-HPLC) was used to analyze the catechins (EGCG) and alkaloids (caffeine) extracted. The content of EGCG and caffeine in green tea extracts was in the range of 2.04∼0.30 and 10.22∼0.85 mg/g, respectively. The amount of EGCG and caffeine in black tea extracts was in the range of 0.32∼0.24 and 5.26∼1.01 mg/g, respectively. The amount of caffeine extracted from green and black tea was greater than the amount of EGCG. Pure water is the best solvent for extracting EGCG and caffeine from green tea. The amount of caffeine extracted from green and black tea increased as the temperature, extraction time, and hydrogen ion concentration of the solvent increased. Although the amount of EGCG extracted from green tea increased as the temperature increased, the amount of EGCG extracted from black tea was not affected by temperature. The extraction of EGCG from both green and black tea was not affected by the hydrogen ion concentration of the solvent.  相似文献   

13.
湘西慈竹叶中黄酮的提取与测定   总被引:1,自引:0,他引:1  
设计正交试验,以溶剂浸提-回流法提取,以分光光度法测定,研究了湘西慈竹叶中总黄酮提取和测定的方法。结果表明:溶剂、溶剂浓度、水浴温度、回流时间4种因素对提取效果影响大小依次为,溶剂>溶剂浓度>回流时间>水浴温度,其中溶剂及其浓度是主要因素,回流时间和水浴温度是次要因素。不同溶剂对慈竹叶总黄酮提取效果影响大小顺序为丙酮>乙醇>乙醚。浸提-回流法提取湘西慈竹叶中黄酮类化合物的优化提取条件(固定料液比为1∶20)是:以75%的丙酮为浸提剂,于70℃下回流加热4 h。在优化提取条件下,测得湘西慈竹叶总黄酮含量为13.0 mg.g-1(春)~12.4 mg.g-1(秋),春季新叶中黄酮含量略高于秋季老叶。湘西慈竹叶总黄酮含量略低于四川南充慈竹叶。  相似文献   

14.
A method for measuring the ethanol concentration in a yeast culture broth was developed using both microtubes and a 96-deepwell microplate. The strategy involved first the solvent extraction of ethanol from the yeast culture broth and measurements of the ethanol concentration using the dichromate oxidation method. Particular focus was made on selecting the extraction solvent as well as determining the measurable range of ethanol concentrations using this solvent extraction-dichromate oxidation method. This method was developed as an assay format in 2.0-ml microtubes and 1.2-ml 96-deepwell microplates, and the ethanol concentration in the batch cultures and fed-batch fermentations was measured. Tri-n-butyl phosphate [non-alcoholic solvent, density = 0.9727, solubility in water = 0.028% (w/v)] was used for solvent extraction when measuring the ethanol concentration from the yeast culture broth. The maximum detectable ethanol concentration was 8% (v/v) when 10 g potassium dichromate in 100 ml of 5 M sulfuric acid was used. The concentrations determined from the solvent extraction-dichromate oxidation methods were remarkably similar to those of gas chromatography in which samples were prepared from seven experiments, such as four batch cultures and three fed-batch fermentations.  相似文献   

15.
The main objective of this study is to establish the best preparation technology of the particles of Acanthopanax senticosus. First, take the reflux extraction method extract of Acanthopanax senticosus coarse powder, optimized by orthogonal experimental method, to flavonoids flavonoids extraction extraction rate as the indexes to determine the effects of extraction temperature, ethanol concentration, extraction time on flavonoids content. Then by a wet granulation of thorn slender acanthopanax particles, taste with granules, forming rate, melting rate as index to investigate the influences of materials adding amount of granules effect. The results showed that the ethanol water heating reflux extraction method to extract the temperature of 70 deg, the percentage of ethanol 75%, extraction time 2.5 h, the highest content of total flavonoids in the extract. Join the 5 ml and 10 g in the extract of acacia honey, dextrin, starch, sugar ratio for 3:4:8, the best taste of Acanthopanax granules. In the end, the best preparation technology of the granules is established, and the process is simple, which is suitable for the large-scale production of the factory.  相似文献   

16.
Seven Hawthorn extracts were tested in isolated guinea pig aorta rings. The effect on noradrenaline- (10 microM) induced contraction was investigated. The extracts were prepared using ethanol (40 to 70% v/v), methanol (40 to 70% v/v), and water as the extraction solvents. The aqueous-alcoholic extracts displayed similar spectra of constituents. They were characterised by similar procyanidin, flavonoid, total vitexin and total phenols content and by similar TLC fingerprint chromatograms. The aqueous extract, however, showed a different fingerprint and a noticeably lower concentration of procyanidins, flavonoids and total phenols but a similar total vitexin content. All 7 extracts had a relaxant effect on the aorta precontracted by noradrenaline and led to relaxations to 44 until 29% of the initial values. The EC50 values of the aqueous-alcoholic extracts varied between 4.16 and 9.8 mg/l. The aqueous extract produced a similarly strong maximal relaxation as the other extracts, but the EC50, at 22.39 mg/l, was markedly higher. The results show that Hawthorn extracts with comparable quality profiles were obtained by using aqueous-alcoholic extraction solvents (40 to 70% ethanol or methanol). The extracts exerted comparable pharmacological effects. When using water as the extraction solvent, both, the spectrum of constituents and the pharmacological effect, deviated remarkably. It is thus possible to obtain bioequivalent extracts with comparable effect profiles by using 40 to 70% ethanol or methanol as the extraction solvent.  相似文献   

17.
Carbon fixation into lipid (lipid production) by phytoplankton was measured in 3 lakes on the edge of the Canadian Shield by two different extraction methods. The amount of lipid detected in the plankton samples was generally 11% lower when extracted by a Folch-like lipid solvent (dichloromethane:methanol (2:1)) than with the lipid solvent (80% ethanol and 80% ethanol-diethyl ether) used in a sequential extraction method. The difference between methods was not due to losses of fixed carbon during extraction since the sum of the extraction fractions from both methods were not different from the amount of carbon fixed on a replicate acidified filter. Although more carbon was detected in the lipid fraction of the sequential extraction method, an additional 5% of total carbon fixed was found in the lipid extract of another fraction from the sequential method, the low molecular weight fraction. Our results suggest that accurate comparisons of lipid production data can only occur after compensating for differences in extraction methods while comparing the LFCF determined by different lipid extraction should be avoided.  相似文献   

18.
超声波法提取野生石蒜中加兰他敏   总被引:2,自引:0,他引:2  
石蒜是我国丰富的野生资源之一,其鳞茎富含重要药用成分加兰他敏。为了获得石蒜中加兰他敏的超声波提取方法,以野生石蒜为原料,用乙醇作提取剂,探讨了超声波提取加兰他敏的工艺条件,并与常规溶剂法进行了比较。分析了料液比、超声波功率、提取温度、提取时间、提取次数等因素对加兰他敏提取效果的影响,运用正交实验L9(34)确定了最佳提取工艺条件。结果显示,超声波提取加兰他敏的最佳工艺条件为:料液比1:6,超声波功率250 W,提取温度60℃,提取时间1.5 h,提取2次;加兰他敏的提取率为94.6%,产率为0.0543%;提取物中加兰他敏含量为15.53%。与常规溶剂法相比,超声波法具有用时少、提取率高、提取次数少等优点,整体效果优于常规溶剂法。  相似文献   

19.
超临界CO2萃取红景天中红景天苷、苷元酪醇的研究   总被引:11,自引:0,他引:11  
采用超临界CO2 萃取法和乙醇常温浸提法相比较, 研究从红景天中提取红景天苷、苷元酪醇的工艺条件, 结论是:采用超临界CO2 萃取法能萃取出红景天生药中红景天苷的1.2%, 提取率不高, 但该方法能萃取出80%的苷元酪醇, 萃取液中苷元酪醇的相对含量可达45.68%;乙醇常温浸提法能将红景天苷、苷元酪醇同时有效萃取, 且得率较高, 但是萃取液中两物质相对含量较低, 进一步分离纯化将有难度。本研究结果表明, 将超临界CO2 萃取法和乙醇常温浸提法有效结合, 可实现两物质的有效分离, 推进红景天有效成分的产业化进程。  相似文献   

20.
基于超高效液相-三重四级杆质谱联用(UPLC-MS/MS)定量检测法优化出一种灵芝三萜热回流提取的工艺。通过本实验建立的灵芝三萜UPLC-MS/MS精确方法检测不同来源的7个栽培品种灵芝子实体中19个三萜化合物的含量,筛选出三萜含量较高的sd-2灵芝子实体作为提取原料,以三萜含量和提取物得率为指标,通过单因素和响应面实验对灵芝三萜的热回流工艺进行优化,获得的最佳条件为:乙醇浓度75%、提取时间2.5h、液料比14:1、提取次数2次。对获得的最佳提取工艺进行中试实验,灵芝子实体乙醇提取物的得率为6.10%,三萜含量为11.8591mg/g。研究结果可为灵芝三萜的工业大规模提取提供理论依据,为灵芝高附加值产品的开发利用提供技术支撑。  相似文献   

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