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1.
High pressure microwave assisted extraction (HPMAE) was applied to extract the ginsenosides from Panax ginseng root. The influences of extraction solvent, extraction pressure and extraction time were individually investigated. HPMAE has been compared with other extraction methods, including Soxhlet extraction, ultrasound-assisted extraction and heat reflux extraction. The determination of ginsenosides was performed by HPLC–ESI-MS. The results indicated that the HPMAE not only took a shorter time but also afforded higher extraction yields of ginsenosides, especially ginsenoside Rb1, Rc, Rb2 and Rd. Furthermore, the neutral ginsenosides and malonyl ginsenosides in Panax ginseng root extracts by HPMAE were investigated. The malonyl ginsenoside m-Rb1, m-Rc, m-Rb2 and m-Rd degraded in HPMAE at 400 kPa (109–112 °C) in 70% (v/v) ethanol–water and at 600 kPa (112–115 °C) in methanol, and transformed into corresponding neutral ginsenoside Rb1, Rc, Rb2 and Rd. Using water as extraction solution, the neutral ginsenosides degraded under HPMAE at 400 kPa (135–140 °C), and transformed into less polarity rare ginsenosides.  相似文献   

2.
利用纤维素酶-乙醇结合法提取人参总皂苷。通过单因素试验考察提取体系pH、纤维素酶添加量、乙醇浓度、酶解温度、料液比、提取时间和提取次数对人参总皂苷提取率的影响。利用正交试验设计得到最优提取条件:提取温度为50℃、提取次数为2次,pH为5.0、乙醇浓度为40%,酶添加量为1.5%、固液比为1∶12、提取时间为2h。在最优条件下,纤维素酶-乙醇结合法提取人参总皂苷的得率为2.73%。对比试验证明,纤维素酶-乙醇结合法提取的人参总皂苷提取率高于参考条件下回流提取法和浸提法。结果证明纤维素酶-乙醇结合法可以得到较高的人参总皂苷提取率。  相似文献   

3.
目的建立保健食品中人参皂苷类成分的提取、检测方法,并对检测方法进行方法学考察。方法以标示含人参成分保健食品为研究对象,样品经溶剂提取,固相萃取小柱净化,超高效液相-串联二极管阵列检测器检测保健食品中人参皂苷类成分。使用建立的方法对市售17批保健食品(标示成分为总皂苷)中的人参皂苷类成分进行含量测定,并与产品总皂苷标示量和传统检测方法的测定结果进行对比,评判含人参成分保健食品品质。结果建立的方法能够快速、准确、灵敏地检测7种皂苷成分。17批标示含人参成分的保健食品所测人参皂苷类成分总量均低于采用《规范》方法所测得的总皂苷含量和产品总皂苷标示含量。结论本研究建立的方法可以客观反映含人参成分保健食品的品质。  相似文献   

4.
目的 建立一种绿色的动态微波辅助快速萃取法结合高效液相色谱-串联质谱法测定苹果中八种氨基甲酸酯类农药的方法。方法 首先,以水为萃取溶剂,利用动态微波辅助萃取法对苹果中氨基甲酸酯类农药进行快速萃取;之后通过两步固相萃取法对所获得的萃取物进行净化和富集;最后,采用高效液相色谱-串联质谱法对目标化合物进行分析。结果 实验中对影响动态微波辅助萃取和固相萃取效率的实验条件进行了优化,最优的实验条件为:萃取剂为纯水,微波萃取功率为600 W;微波萃取时间为10 min;萃取剂流速为1.0 mL min-1;固相萃取洗脱剂为2 mL的乙醇。八种氨基甲酸酯类农药在8~800 ng g-1范围内成线性关系,相关系数为0.994~0.999;检出限为1.1~4.2 ng g-1;方法的加标(8 ng g-1)回收率为71%~90%。结论 该方法可以用于苹果中氨基甲酸酯类农药的快速检测。  相似文献   

5.
Ultrasonic cell grinder extraction (UCGE), employing water as solvent, was proposed as a sustainable and efficient method for the extraction of two iridoid glycosides (morroniside and loganin) from Corni fructus. Extraction yields were determined by four variables: ratio of solution to solid, extraction power, extraction buffer time and extraction time. Data analysis by response surface methodology showed that best yields, 2.176% ± 0.006% (predicted value of 2.195%) for morroniside and 0.839% ± 0.004% (predicted value of 0.852%) for loganin, were obtained when the values of these four variables were set at 45:1 mL g?1, 1600 w, 2.3 s and 40 min, respectively. The yields of morroniside and loganin using UCGE method were 0.198–0.279% and 0.167–0.181% higher than that of traditional heat reflux extraction method, respectively. Thus, the UCGE method is more productive, economic and environmentally friendly and has great potential to be used widely in natural product chemistry.  相似文献   

6.
紫皮洋葱油索氏提取工艺优化   总被引:2,自引:1,他引:1  
采用响应曲面法对紫皮洋葱油提取工艺进行优化。以紫皮洋葱油得率为指标,采用索氏提取法,对提取溶剂,提取时间,料液比和回流温度等提取条件进行单因素试验。在此基础上,根据Box-Benhnken中心组合方法进行三因素三水平的试验设计,并进行响应面分析。结果表明,紫皮洋葱油最佳提取工艺条件为:石油醚为溶剂,料液比为3.64/80(g:mL),提取时间为3.83h,回流温度为78.49℃。在此工艺条件下,紫皮洋葱油得率理论值为0.462%,实测值为0.470%,与理论值相比,相对误差为1.73%。  相似文献   

7.
本研究建立了一种磁力搅拌辅助的超临界CO2萃取法,用于提取五味子中的8种木脂素类化合物,采用高效液相色谱对目标分析物进行分离和测定。本研究以超临界CO2作为萃取溶剂,采用乙醇溶液预先浸渍样品,通过磁力搅拌促进样品与超临界CO2的充分接触,以提高传质效率。本研究对影响木脂素类化合物提取率的各个因素进行了优化,并与传统方法进行了比较。实验结果表明,各目标分析物在线性范围内具有良好的线性关系(r>0.9998),检出限和定量限为21.30~990.20 ng/mL和60.80~2992.80 ng/mL,加标样品回收率在75.00%~97.78%之间,分析结果令人满意。与其他方法相比,虽然本法在提取时间和实验成本上并不占优势,但本法所获得的提取率明显高于微波提取法和热回流提取法,并与药典方法相似,尽管本法在萃取过程中使用了少量的有机溶剂,但料液比仅为1:2,是其他方法的1/25~1/50。本法具有样品处理量大、操作简单、绿色环保、萃取效率高等优点,在工业化生产应用方面具有一定潜质,可用于中药中木脂素类化合物的提取分离。  相似文献   

8.
以万年蒿为原料,研究超声波提取万年蒿总黄酮的最佳工艺。通过单因素试验研究乙醇体积分数、料液比、超声波功率及超声时间对总黄酮提取量的影响。以此为基础,采用L9(34)正交试验设计,优化超声波提取万年蒿总黄酮工艺条件;并将其与传统的热回流法和浸提法进行了比较。超声波提取万年蒿总黄酮的最佳提取工艺参数为:乙醇体积分数60%,料液比1∶20(g:mL),超声波功率350 W,超声时间60 min。在此工艺条件下,万年蒿总黄酮提取量为69.55 mg/g。  相似文献   

9.
The pressurized liquid extraction and HPLC-DAD was developed for extraction and determination of bioactive lignans in Schisandra chinensis. The efficient PLE conditions employed methanol as extraction solvent, 125 °C of extraction temperature, 5 min of static extraction time and only one cycle. A rapid HPLC-DAD method was described for simultaneous determination of nine lignans, including schisandrol A, gomisin J, schisandrol B, tigloylgomisin H, angeloylgomisin H, schisandrin A, γ-schisandrin, gomisin N and schisandrin C. The extraction efficiency of PLE was observed to be comparable with reflux and sonication. In addition, the contents of nine lignans in S. chinensis from different regions were analysed by PLE and HPLC-DAD method.  相似文献   

10.
目的优化酸浆中木犀草苷成分的提取工艺。方法选取干燥的酸浆[Physalisalkekengi L.var.franchetii(Mast.)Makino]宿萼作为实验材料,分别使用甲醇、乙醇和水作为溶剂,考察超声、热回流和渗漉对木犀草苷提取效率的影响。结果以乙醇作为提取溶剂,采用加热回流的提取方式,木犀草苷得率较高。运用单因素考察法及正交实验确定了最佳工艺条件:使用乙醇溶液,料液比1:30(g/mL),加热回流90 min,提取3次,木犀草苷得率可达1.28%。结论经过优化后,酸浆提取所选用试剂安全可靠,木犀草苷得率显著提高。  相似文献   

11.
HS-SPME coupled to GC/MS was applied to the analysis of the volatile fraction of Juniperus communis L. berries, which are the principal ingredient used for gin aromatization. Seventy seven compounds were identified by comparison with reference compounds or tentatively identified by comparing their mass spectra and retention index with those reported in mass spectra libraries and literature, respectively. Seventy four were detected by SPME and sixty eight were detected by solvent distillation extraction (SDE). These were mainly mono- and sesquiterpenic compounds that represented more than the 80% of the gin’s volatile composition. A high percent content was due to monoterpenoids, whose analysis could be important for the assessment of sensory quality control of juniper due to their impact on gin aroma. The main monoterpenoids detected in the headspace of the juniper berries from two periods of collection were terpinen-4-ol, p-cymene, β-myrcene, γ-terpinene, α-pinene and limonene. These represented more than the 70% of the sample’s volatile fraction. The proposed SPME method required short times and the low cost of analysis and enabled to detect a number of compounds comparable with SDE or much higher than the number of compounds reported by other extraction techniques. The results suggested the suitability of this technique for the assessment of the volatile composition of juniper berries intended for gin flavouring.  相似文献   

12.
High hydrostatic pressure (HHP) extraction method was optimized to maximize the extraction yield of kirenol from Siegesbeckia orientalis. Operating parameters such as extraction pressure (100–600 MPa), pressure holding time (3–20 min), feed-to-solvent ratio (1:10–1:90 (w/v)), and solvent (ethanol) concentration (0–100%) were investigated individually by mono-factor experiments. Then, the optimal extraction conditions were determined using response surface methodology. Box-Behnken design was applied to evaluate the effects of three independent variables (extraction pressure, solvent concentration, and feed-to-solvent ratio) on the extraction yield of kirenol from S. orientalis. Extraction pressure, solvent concentration, and feed-to-solvent ratio affected the extraction yields significantly, whereas the pressure holding time had no significant effect. The optimal processing conditions, which gave a maximum extraction yield of 85.9% kirenol from the raw material, were as follows: extracting pressure 320 MPa, pressure holding time 5min, ethanol concentration 18%, and feed-to-solvent ratio 1:76 (w/v).  相似文献   

13.
Microwave-assisted solvent extraction (MASE) of oil from olive cake can be used as an alternative for conventional solvent extraction (CSE).The present research showed that, compared to the CSE, the MASE gave better yields within very short times. The results obtained with this new procedure indicated that the radiation power and exposition time enhanced extraction ability.The Patricelli model has been applied to describe the MASE kinetic. The coefficients of determination were found to be very high in all the cases (R2  0.992) indicating a good fit of the experimental data at tested conditions. The results obtained were compared with those given by the same model in the case of the conventional extraction.Industrial relevanceOlive cake pollutes the environment around the Mediterranean basin where it is generated in great amounts within a short period (from November to March). To avoid this pollution, it must be treated. Its valorization by recovery of its residual oil using conventional solvent extraction is time-consuming and needs large volumes of solvent. Compared to this conventional technique, the microwave-assisted solvent extraction can be a nice alternative because it gives better yields within short times and consumes less solvent.  相似文献   

14.
通过单因素试验和正交试验对微波辅助萃取人参皂苷的工艺条件进行优化,采用分光光度法和高效液相色谱法对萃取物中的人参总皂苷及8种单体皂苷进行测定,考察不同提取条件下所得人参皂苷产率和组成的差异。结果表明:1)以总皂苷为提取目标时,最佳提取条件为萃取功率600 W、萃取温度45℃、萃取时间5 min、料液比1∶20,萃取3次;2)以8种单体皂苷为提取目标时,最佳提取条件为萃取功率300 W、萃取温度35℃、萃取时间15 min、料液比1∶25,萃取3次(提取率为0.98%);3)在最佳提取条件下,以体积分数80%甲醇为提取溶剂时,总皂苷提取率为6.02%,而单体皂苷提取率之和为0.43%;以水饱和正丁醇为提取溶剂时8种单体皂苷提取率达到0.71%。综上所述,人参质量评价和工艺优化结果与提取方法、提取条件、评价指标密切相关。  相似文献   

15.
Ginseng and lingzhi (Ganoderma lucidum) both are valuable traditional Chinese medicines and have been extensively utilised in functional foods and traditional medicines in many Asian countries. However, massive quantity of ginseng residue is produced after extraction of ginseng which still contains a lot of bioactive compounds such as ginsenosides. The goal of this study was to reuse the American ginseng extraction residue as the fermentation medium of G. lucidum to produce bioactive ginsenoside enriched biotransformation products. The changes of ginsenosides in the fermentation products were analysed during fermentation. Our results showed that after 30 days of fermentation, ginsenoside Rg1, Rd, and compound K (CK) significantly increased, especially Rd, while other ginsenosides (Re, Rb1 and Rc) decreased during fermentation. Ginsenoside Rd is the major ginsenoside in the final fermentation product. Furthermore, the biotransformation of ginsenosides was the major reaction in this fermentation process.  相似文献   

16.
The response surface methodology (RSM) was employed to optimize the ultrasound extraction of flavanols and anthocyanins from the pulp of jussara (Euterpe edulis), using a second-order polynomial equation to describe the experimental data for total flavanol (TF), total phenolic (TP), and total monomeric anthocyanin (TMA) contents, as well as the total antioxidant activity (TAA). A central composite design with two-variables (extraction time and solid to liquid ratio) was then applied. The optimized conditions that maximized the yields of flavanol-enriched extract were a solvent methanol/0.1 M HCl, solid to liquid ratio of between 1:50 and 1:100 and extraction time of 15 min. For anthocyanin-enriched extracts the respective optimal parameters were a solvent methanol/1.5 M HCl, solid to liquid ratio of between 1:30 and 1:50 and extraction time of 24 h. The results showed good fits with the proposed model for both the flavanol-enriched extract (R2 = 0.94) and for the anthocyanin-enriched extract (R2 = 0.99).  相似文献   

17.
Panax ginseng (P. ginseng) has been used as a traditional medicine for thousands of years. It includes P. ginseng root, leaf, root-hair, rhizome and stem. P. ginseng root is usually considered to be the main part for medicine, and other parts of P. ginseng are neglected. In this paper the content of ginsenosides in different parts and ages of P. ginseng was determined. Separation and determination of seven major ginsenosides, including Rg1, Re, Rb1, Rc, Rb2, Rb3 and Rd, has been achieved by high performance liquid chromatography (HPLC) with UV detector at 203 nm. The extraction of ginsenosides from P. ginseng material was performed by microwave-assisted extraction (MAE). The results indicate that the content of ginsenosides is higher in the leaf and root-hair, and lower in stem than that in other parts of P. ginseng. The content of ginsenosides in root and root-hair increases with increase in age of P. ginseng from one to five years. However, the total content of ginsenosides in P. ginseng leaf decreases with the increase in age.  相似文献   

18.
Hui Wang 《LWT》2011,44(6):1490-1495
A rapid method based on dynamic microwave-assisted extraction (DMAE) coupled on-line with clean-up was developed for the determination of caffeine in tea samples. A TM010 microwave resonance cavity was applied to concentrate the microwave energy. An extraction vessel was placed in microwave irradiation zone of the TM010 microwave resonance cavity. A silica gel column connected with the extraction vessel was used to remove chlorophyll in tea. The extraction and clean-up procedures were carried out simultaneously in a single step. The DMAE parameters were optimized by the Box-Behnken design. The maximum extraction efficiency was achieved using 70 W of microwave power, 3.5 mL of extraction solvent and 1.0 mL min−1 of extraction solvent flow rate. The limit of detection obtained is 0.012 mg g−1. The RSDs of intra- and inter-day of eight kinds of tea samples are 2.7%-5.4% and 5.1%-7.3%, respectively. The recovery of caffeine in the tea samples is in the range of 88.2%-99.3%.The proposed method has selectivity and sensitivity and considerably less labor and time for determination of caffeine in tea compared with conventional extraction methods, such assoxhlet extractionand liquid-liquid extraction.  相似文献   

19.
The stabilization of all-trans-lycopene from tomato by encapsulation using α-, β- and γ-cyclodextrins (CDs) was evaluated. To that end, two different encapsulation methods were comparatively studied: a conventional method and a supercritical fluid extraction (SFE) process. An optimization procedure considering distinct molar ratios of CD/lycopene (1/0.0026, 1/0.005 and 1/0.05) as well as the type of cyclodextrin to be used was accomplished. The encapsulation was determined by using micro-Raman spectroscopy. All-trans-lycopene employed was obtained by SFE with a purity around 90–95%. As a result, a molar ratio CD/lycopene of 1/0.0026 was selected as it provided the best complexation yields (93.8%) whilst β-CD seemed to be the most favorable to be used to stabilize lycopene. A comparison of the two methods studied reflected higher encapsulation yields from the conventional method. However, the supercritical fluid approach offers numerous advantages such as the possibility of performing the extraction, fractionation and encapsulation of lycopene from tomato in one step, shortening notably the overall procedure time and minimizing the sample handling.  相似文献   

20.
This study developed a method for enriched separation of protopanaxatriol ginsenosides, malonyl ginsenosides and protopanaxadiol ginsenosides from Panax ginseng. The method began with targets extraction from herbal material, followed by HPD300 resins separation, then extracted by water-statured n-butanol. In the product achieved, protopanaxatriol ginsenosides were 24.4% pure with 70.9% recovery, malonyl ginsenosides were 33.4% pure with 23.3% recovery, and protopanaxadiol ginsenosides as well as Ro were 31.3% pure with 56.8% recovery. The adsorption test data on HPD300 resins fit the Langmuir model well. Moreover, the pseudo-first-order kinetic model showed the best correlation with the adsorption results. These findings indicate that the combination of HPD300 resin chromatography and water-statured n-butanol extraction effectively separates and enriches ginsenosides from P. ginseng.  相似文献   

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