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Effects of ultrahigh pressure extraction on yield and antioxidant activity of chlorogenic acid and cynaroside extracted from flower buds of Lonicera japonica 被引量:17
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作者 HU Wen GUO Ting +4 位作者 JIANG Wen-Jun DONG Guang-Li CHEN Da-Wei YANG Shi-Lin LI He-Ran 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第6期445-453,共9页
The present study was designed to establish and optimize a new method for extracting chlorogenic acid and cynaroside from Lonicera japonica Thunb. through orthogonal experimental designl. A new ultrahigh pressure extr... The present study was designed to establish and optimize a new method for extracting chlorogenic acid and cynaroside from Lonicera japonica Thunb. through orthogonal experimental designl. A new ultrahigh pressure extraction (UPE) technology was applied to extract chlorogenic acid and cynaroside from L. japonica. The influential factors, including solvent type, ethanol concentration, extraction pressure, time, and temperature, and the solid/liquid ratio, have been studied to optimize the extraction process, The optimal conditions for the UPE were developed by quantitative analysis of the extraction products by HPLC-DAD in comparison with standard samples. In addition, the microstructures of the medicinal materials before and after extraction were studied by scanning electron microscopy (SEM). Furthermore, the extraction efficiency of different extraction methods and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of the extracts were investigated. The optimal conditions for extracting chlorogenic acid and cynaroside were as follows: ethanol concentration, 60%; extraction pressure, 400 MPa; extraction time, 2 rain; extraction temperature, 30 ℃; and the solid/liquid ratio, 1 : 50. Under these conditions, the yields of chlorogenic acid and cynaroside were raised to 4.863% and 0.080%, respectively. Compared with other extraction methods, such as heat reflux extraction (HRE), ultrasonic extraction (UE), and Sohxlet extraction (SE), the UPE method showed several advantages, including higher extraction yield, shorter extraction time, lower energy consumption, and higher purity of the extracts. This study could help better utilize L. japonica flower buds as a readily accessible source of natural antioxidants in food and pharmaceutical industries. 展开更多
关键词 Lonicerajaponica Thunb. Ultrahigh pressure extraction Chlorogenic acid Cynaroside Antioxidant activity
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Determination of Seven Major Ginsenosides in Different Parts of Panax quinquefolius L.(American Ginseng) with Different Ages 被引量:14
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作者 ZHANG Kun WANG Xiao +5 位作者 DING Lan LI Juan QU Chen-ling CHEN Li-gang JIN Hai-yan ZHANG Han-qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期707-711,共5页
Ginsenosides Rgl, Re, Rb1, Rc, Rb2, Rb3, and Rd in different parts of the American ginseng plant were investigated. The extraction process was a pressurized microwave-assisted extraction(PMAE). The seven ginsenoside... Ginsenosides Rgl, Re, Rb1, Rc, Rb2, Rb3, and Rd in different parts of the American ginseng plant were investigated. The extraction process was a pressurized microwave-assisted extraction(PMAE). The seven ginsenosides were separated and determined by high-performance liquid chromatography(HPLC) with a ultraviolet(UV) detector, at 203 nm. The experiment results showed significant variations in the individual ginsenoside contents of the American ginseng in different parts and ages of the plant. The results demonstrated that the leaves, root hairs, and rhizomes of Panax quinquefolius L. contained higher ginsenoside contents, followed by the main roots and stems. The leaves contained dramatically higher levels of ginsenoside Rg1 Rb3, and Rd than the other four parts. Higher contents of Rb1 and Re were present in the main roots, root hairs, and rhizomes. The amount of ginsenoside content in the stems was the lowest. The total content of the seven ginsenosides in main roots, root hairs and rhizomes increased with the age of the plant. In contrast, the ginsenoside contents in the leaves and stems decreased with a year of growth. 展开更多
关键词 American ginseng GINSENOSIDE High performance liquid chromatography Pressurized microwave-assisted extraction
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Determination of berberine in Phellodendron amurense from different sites of Changbai Mountain 被引量:2
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作者 Lin Ma Jun-qing Li Yuan-dong Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期201-207,共7页
Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active c... Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active compound contained in P. amurense. Our objective in this study was to quantify the content of berberine in P.amurense from sites at different elevations on Changbai Mountain. We collected samples of P. amurense from five different elevations on Changbai Mountain. Berberine in samples was extracted by ultrahigh pressure extraction(UPE). And the quantity was measured by high performance liquid chromatography(HPLC). First, the optimal HPLC conditions for berberine were identified with satisfactory precision(relative standard deviation, R SD/5.6 %), good accuracy(relative error, R E/ 3.6 %) and good linear relation(R2= 0.9998) in the range of 6.576–328.8 mg L-1. Second, the combination of UPE and HPLC methods in quantitative analysis of berberine showed high repeatability(R SD= 3.28 %), reproducibility(R SD= 4.72 %),stability(R SD/ 1.27 %) and good recovery(99.54 %) for real plant materials. Samples from Heilongjiang Province at the lowest elevation contained the highest amount of berberine.Similarly, the lowest amount of berberine was recorded in samples from Changbai Forest Bureau of Jilin Province collected at the highest elevation in this paper. The proposed UPE–HPLC method is simple, reliable and low-cost for quantitative analysis of berberine. Content of berberine in P.amurense varied significantly by site on Changbai Mountain. 展开更多
关键词 Phellodendron amurense Berberine Changbai Mountain Altitudes Ultrahigh pressure extraction High performance liquid chromatography
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Design aspect of a novel L-shaped pulsed column for liquid–liquid extraction applications: Energy consumption and the characteristics velocity concept 被引量:3
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作者 Pouria Amani Elham Mohammadi Sahar Akhgar 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第4期723-730,共8页
This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the peri... This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions. 展开更多
关键词 Solvent extraction Pulsed plate column pressure drop Energy consumption Pulsed flow Characteristic velocity
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Determination of Sulphonamide Antibiotics and Trimethoprim in Wastewater and Sludge Using Liquid Chromatography with Diode-Array Detection 被引量:1
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作者 Petra Zenatova Milada Vavrova Ludmila Mravcova Hana Lisa 《Journal of Environmental Science and Engineering(A)》 2012年第2期175-180,共6页
This paper investigates the occurrence of sulphonamide and diaminopyrimidine antibiotics in wastewater and sludge from wastewater treatment plants. In our experiment, they were isolated from wastewater using the solid... This paper investigates the occurrence of sulphonamide and diaminopyrimidine antibiotics in wastewater and sludge from wastewater treatment plants. In our experiment, they were isolated from wastewater using the solid phase extraction method. In the case of sludge, pressurized solvent extraction techniques were used followed by solid phase extraction. The solid phase extraction method was used for purification and concentration. Sulphonamide and diaminopyrimidine antibiotics were determined using high performance liquid chromatography with diode-array detection. The selected antibiotics were determined in real sludge samples collected from the wastewater treatment plant in Brno-Mod^ice and in real wastewater samples collected from the wastewater treatment plant located on the grounds of the University of Veterinary and Pharmaceutical Sciences in Brno, using the developed and optimized method. Analyses showed that real samples of wastewater contained sulphathiazole 11.82μg/L at the inflow (7.1 μg/L at the outflow), sulphapyridine 18.57 I.tg/L (12.2 μg/L), sulphamethazine 13.52 μg/L (8.44 μg/L), sulphamethoxazole 14.06 lag/L (9.34 Ixg/L) and trimethoprim 521.4 lag/L (422.29 μg/L). Here it is demonstrated that drugs are removed through the wastewater treatment procedure only partially. 展开更多
关键词 Drug residues ANTIBIOTICS SLUDGE WASTEWATER pressurized solvent extraction liquid chromatography.
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Effectiveness of groundwater extraction in Beijing since the ingauration of the first phase of the South-to-North Water Diversion Project, China
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作者 Yuan-yuan Gao Qing-yu Sun +1 位作者 Ai-xin Wen Yan-pei Cheng 《Journal of Groundwater Science and Engineering》 2023年第3期294-307,共14页
This study assess the effectiveness of groundwater pressure extraction in Beijing since the opening of the first phase of the South-to-North Water Diversion Project,using survey and evaluation methods.Firstly,an analy... This study assess the effectiveness of groundwater pressure extraction in Beijing since the opening of the first phase of the South-to-North Water Diversion Project,using survey and evaluation methods.Firstly,an analysis of water consumption structure and the usage of diverted river water in Beijing in recent years was conducted.Secondly,the volume of groundwater pressure extraction in Beijing after the 33 project's inauguration was examined,revealing a decrease from 1.96 billion m^(3) in 2014 to 1.35 billion m^(3) in 2020.The proportion of water supply reduced from 52.3%in 2014 to 33.3%in 2020,leading to an optimized water supply structure.By the end of 2020,groundwater pressure extraction in Beijing is estimated at 446 million m3,with a substantial reduction in over-exploitation of groundwater.Groundwater resources have been effectively replenished,and the strategic reserve capacity has been enhanced.Furthermore,this study evaluates the change in groundwater levels as an indicator of the effectiveness of pressure extraction.The declining trend of groundwater levels in Beijing has been effectively mitigated,and there has been a consistent rebound in groundwater levels over the past five years. 展开更多
关键词 Beijing City South-to-North Water Diversion Groundwater Over-exploitation Groundwater pressure Extraction
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Selective laser trabeculoplasty in pseudophakic and phakic eyes:a prospective study
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作者 Myrjam De Keyser Maya De Belder Veva De Groot 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期593-598,共6页
AIM:To compare the efficacy of selective laser trabeculoplasty(SLT) in replacing medical therapy in pseudophakic and phakic eyes.METHODS:Subgroup of a prospective randomized clinical trial including patients with ... AIM:To compare the efficacy of selective laser trabeculoplasty(SLT) in replacing medical therapy in pseudophakic and phakic eyes.METHODS:Subgroup of a prospective randomized clinical trial including patients with primary open angle glaucoma or ocular hypertension controlled with medication.Of 38 pseudophakic eyes were matched with 38 phakic eyes.SLT was offered as a way to decrease medication while maintaining the same low eye pressure.SLT was performed over 360°,at 3ns,spotsize 400 μm,100 spots.Data [intraocular pressure(IOP),number of medications needed] were measured at 1h,1wk,1,3,6 and 12 mo.An independent-samples t-test was performed to compare baseline characteristics of the phakic and the pseudophakic group and differences in evolution of mean IOP and number of used medications.Chi-squared analysis was performed to investigate proportions of fast,slow and non-responders.RESULTS:The mean IOP measurement was 13.00± 2.88 mm Hg in the phakic group(38 eyes) and 13.51±3.06 mm Hg in the pseudophakic group(38 eyes)(P〉0.05).This changed little after SLT and IOP lowering effect was comparable between the two groups.Main aim however was to lower the amount of medication needed.In the phakic group medication lowered from 1.29±0.62 at baseline,to 0.15±0.46 after 12mo;a reduction of 88.37%.In the pseudophakic group,used medication changed from 1.71±1.04,to 0.41±0.61;a 76.02% reduction.The differences were not statistically significant at any time point(P〉0.05).IOP lowering occurred slightly faster in thepseudophakic group(50% of patients after one week) than in the phakic group(68% of patients after more than 4wk).The difference was not significant(P〉0.05).CONCLUSION:IOP lowering effect of SLT is comparable between phakic and pseudophakic eyes. 展开更多
关键词 mechanism of trabeculoplasty selective laser trabeculoplasty pseudophakes versus phakic eyes open angle glaucoma pressure lowering after lens extraction
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Pressure shear assisted extraction of polysaccharide from Auricularia auricula and its biological activities
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作者 Yuetong Chen Wenhao Yu +3 位作者 Shanshan Zhang Yabin Niu Yanrong Zhang Tingting Liu 《Journal of Future Foods》 2023年第1期29-36,共8页
In this paper,using to the comprehensive scoring method,pressure shear assisted extraction was used to prepare polysaccharide from Auricularia auricula(PS-AAP)by orthogonal test to optimize the extraction.The highest ... In this paper,using to the comprehensive scoring method,pressure shear assisted extraction was used to prepare polysaccharide from Auricularia auricula(PS-AAP)by orthogonal test to optimize the extraction.The highest comprehensive score(90.70)was obtained under 1:70 g/mL solid-liquid ratio,110°C reaction temperature,60 min reaction time and 1.0 MPa reaction pressure.Compared to AAP by water bath(WB-AAP),PS-AAP led to a higher extraction efficiency and decreased the relative molecular weight.In addition,infrared spectrum(FT-IR)analysis showed that pressure shear assisted did not change the polysaccharide structure.Scanning electron microscope(SEM)showed that PS-AAP was smaller and more broken by pressure shear assisted.Furthermore,the ratio of glucose to mannose in PS-AAP was relatively higher than WB-AAP,which also proved that PS-AAP had certain antioxidant and hypoglycemic activities.Compared with WB-AAP,the inhibitionα-glucosidase andα-amylase activity of PS-AAP increased by 11.37%and 24.43%respectively.These results revealed that PS-AAP has the poten-tial value of being a antioxidant and hypoglycemic agent. 展开更多
关键词 pressure shear assisted extraction Auricularia auricula polysaccharide Structural characterization Biological activities
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Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event
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作者 Hua Tang Ying Wang +2 位作者 Shengling Si Hongli Li David Da Yong Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期237-247,共11页
A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce ... A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year. 展开更多
关键词 Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control
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Pressurized Liquid Extraction of Pigments from Chlamydomonas sp.and Chemical Characterization by HPLC–MS/MS 被引量:1
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作者 Lidia Montero Mahshid Sedghi +6 位作者 Yolanda García Carlos Almeida Carl Safi Nicole Engelen‑Smit Alejandro Cifuentes Jose A.Mendiola Elena Ibáñez 《Journal of Analysis and Testing》 EI 2018年第2期149-157,共9页
Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas sp.An experimental design is employed to determine the effect of th... Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas sp.An experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC tests.All the extracts show significant antioxidant activity in all assays.Besides,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′. 展开更多
关键词 Antioxidant capacity Chlamydomonas sp. HPLC–DAD–APCI–MS/MS PIGMENTS Pressurized liquid extraction Carotenoids
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