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Fang Yuan - One of the best experts on this subject based on the ideXlab platform.
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subcritical water extraction and antioxidant activity evaluation with on line hplc ABTS Assay of phenolic compounds from marigold tagetes erecta l flower residues
Journal of Food Science and Technology-mysore, 2014Co-Authors: Honggao Xu, Weiyou Wang, Junping Jiang, Fang YuanAbstract:Subcritical water extraction (SWE) of phenolics was investigated from marigold (Tagetes erecta L.) flower residues. The total phenolics content (TPC), total flavonoids content (TFC) and antioxidant capacities of extracts were determined, furthermore, antioxidant activities of individual compounds were evaluated with on-line HPLC–ABTS•+ system. The optimum SWE time was 45 min, solid-to-liquid ratio was 1:50, and the highest TPC and TFC were obtained at 220 °C respectively. The effect of SWE temperature on TPC and TFC was significant (p < 0.05), and TPC was ranged from 28.42 ± 0.94 to 124.27 ± 1.94 (mg GAE/g), and TFC ranged from 34.21 ± 0.36 to 133.22 ± 1.57 (mg GAE/g) between 80 and 220 °C. On-line HPLC–ABTS•+ profiles revealed that quercetagetin from SWE at 200 °C had nearly twofold radical scavenging activities than that by leaching extraction.
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subcritical water extraction of phenolic compounds from pomegranate punica granatum l seed residues and investigation into their antioxidant activities with hplc ABTS Assay
Food and Bioproducts Processing, 2012Co-Authors: Li He, Honggao Xu, Fang Yuan, Xiaofei Zhang, Chao Xu, želiko Knez, Zoran NovakAbstract:Abstract Subcritical water extraction (SWE) of phenolic compounds from pomegranate seed residues (PSR) was performed. Total phenolic content (TPC) and antioxidant capacities of the extracts obtained at different temperatures were determined, and the individual antioxidant capacities were evaluated by coupling high performance liquid chromatography with ABTS radical reaction system (HPLC–ABTS +). The results showed that the optimum extraction time was 30 min, solid to water ratio was 1:40, and the highest TPC was obtained at 220 °C. The effect of extraction temperature on TPC was significant (p + profiles revealed that nine compounds had antioxidant activity. Furthermore, the formation of Maillard reaction products during SWE was investigated, and the content of 5-hydroxymethylfurfural (5-HMF) was determined. The comparative study indicated that SWE was a promising technique for preparation of PSR phenolics.
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identification of phenolic compounds from pomegranate punica granatum l seed residues and investigation into their antioxidant capacities by hplc ABTS Assay
Food Research International, 2011Co-Authors: Li He, Honggao Xu, Wenhao He, Fang YuanAbstract:Abstract In this study, phenolic compounds were extracted and isolated from pomegranate seed residue (PSR). Phytochemicals and antioxidant capacity of extracts from PSR were firstly investigated. Total phenolic (TP) and proanthocyanidin (PC) contents of the extracts were determined as 2427.90 and 505.63 mg catechin equivalent of 100 g dry weight respectively. To evaluate the antioxidant capacity of individual compounds, on line Assay of coupling high performance liquid chromatographic separation with ABTS free radical reaction system (HPLC–ABTS + ) was carried out. 17 compounds in PSR extracts were detected with antioxidant capacity, and HPLC associated with electrospray ionization mass spectrometry (HPLC–ESI–MS) was used to identify them. The main phenolics in PSR identified were flavol-3-ols, phenolic acids, flavonoid glycosides, and hydrolysable tannin. The results showed that PSR contained some amount of antioxidant compounds, and the HPLC–ABTS + on line method was fast, sensitive and effective.
Furio Brighenti - One of the best experts on this subject based on the ideXlab platform.
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Application of the 2,2‘-Azinobis(3-ethylbenzothiazoline-6-sulfonic acid) Radical Cation Assay to a Flow Injection System for the Evaluation of Antioxidant Activity of Some Pure Compounds and Beverages
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nicoletta Pellegrini, Barbara Colombi, Marta Bianchi, Furio BrighentiAbstract:The 2,2‘-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) Assay was adapted to a flow injection (FI) system to obtain a sensitive and rapid technique for the monitoring of antioxidant activity of pure compounds and complex matrixes, such as beverages and food extracts. The FI system includes a HPLC pump that flows the mobile phase (a solution of ABTS•+ in ethanol) through a 20 μL loop injector, a single bead string reactor filled with acid-washed silanized beads, a delay coil and a photodiode array UV−visible detector. The technique was very sensitive, with limits of detection and of quantification of 4.14 and 9.29 μmol of Trolox/L, respectively, and demonstrated high repeatability and reproducibility. The proposed technique was then applied to the evaluation of the antioxidant activity of some pure compounds, demonstrating good agreement with published data obtained by the original spectrophotometric ABTS•+ Assay. Finally, the total antioxidant activity of 10 beverages was determi...
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application of the 2 2 azinobis 3 ethylbenzothiazoline 6 sulfonic acid radical cation Assay to a flow injection system for the evaluation of antioxidant activity of some pure compounds and beverages
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nicoletta Pellegrini, Barbara Colombi, Marta Bianchi, Furio BrighentiAbstract:The 2,2‘-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) Assay was adapted to a flow injection (FI) system to obtain a sensitive and rapid technique for the monitoring of antioxidant activity of pure compounds and complex matrixes, such as beverages and food extracts. The FI system includes a HPLC pump that flows the mobile phase (a solution of ABTS•+ in ethanol) through a 20 μL loop injector, a single bead string reactor filled with acid-washed silanized beads, a delay coil and a photodiode array UV−visible detector. The technique was very sensitive, with limits of detection and of quantification of 4.14 and 9.29 μmol of Trolox/L, respectively, and demonstrated high repeatability and reproducibility. The proposed technique was then applied to the evaluation of the antioxidant activity of some pure compounds, demonstrating good agreement with published data obtained by the original spectrophotometric ABTS•+ Assay. Finally, the total antioxidant activity of 10 beverages was determi...
Jin Yeul - One of the best experts on this subject based on the ideXlab platform.
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Antioxidant and Anti-Inflammatory Activity Determination of One Hundred Kinds of Pure Chemical Compounds Using Offline and Online Screening HPLC Assay
Evidence-based Complementary and Alternative Medicine, 2015Co-Authors: You Chang Oh, Jin YeulAbstract:This study investigated the antioxidant activity of one hundred kinds of pure chemical compounds found within a number of natural substances and oriental medicinal herbs (OMH). Three different methods were used to evaluate the antioxidant activity of DPPH radical-scavenging activity, ABTS radical-scavenging activity, and online screening HPLC-ABTS Assays. The results indicated that 17 compounds exhibited better inhibitory activity against ABTS radical than DPPH radical. The IC50 rate of a more practical substance is determined, and the ABTS Assay IC50 values of gallic acid hydrate, (+)-catechin hydrate, caffeic acid, rutin hydrate, hyperoside, quercetin, and kaempferol compounds were 1.03 ± 0.25, 3.12 ± 0.51, 1.59 ± 0.06, 4.68 ± 1.24, 3.54 ± 0.39, 1.89 ± 0.33, and 3.70 ± 0.15 μg/mL, respectively. The ABTS Assay is more sensitive to identifying the antioxidant activity since it has faster reaction kinetics and a heightened response to antioxidants. In addition, there was a very small margin of error between the results of the offline-ABTS Assay and those of the online screening HPLC-ABTS Assay. We also evaluated the effects of 17 compounds on the NO secretion in LPS-stimulated RAW 264.7 cells and also investigated the cytotoxicity of 17 compounds using a cell counting kit (CCK) in order to determine the optimal concentration that would provide an effective anti-inflammatory action with minimum toxicity. These results will be compiled into a database, and this method can be a powerful preselection tool for compounds intended to be studied for their potential bioactivity and antioxidant activity related to their radical-scavenging capacity.
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antioxidant activity analysis of useful compounds from artemisiae annuae herba using on line screening hplc ABTS Assay
Journal of Applied Biological Chemistry, 2014Co-Authors: Jin YeulAbstract:Abstract The Antioxidant activity screening identification offive kind compounds in Artemisiae annuae herba with the on-linescreening high performance liquid chromatography (HPLC)ABTS + Assay. The various experimental variables such as theextraction time (h) and extraction solvent composition (%) ofdipping method were investigated efficiently extraction at theroom temperature 25 o C. The results, the highest yield of totalextract amount (0.458 g, 15.250%) was obtained by dippingmethod with 100% water and extraction time to 3 h. And the on-line screening HPLC-ABTS + Assay method was rapid and efficientto search for bioactivity from natural products.Keywords analysis · annuae herba · artemisiae · identification ·on-line screening high performance liquid chromatography청호(Artemisiae Annuae Herba 이하 AAH)는 널리 한국, 일본,중국 등에 널리 분포되어 있으며 향이 강하고 독특하며 대부분약재로 사용되고 있다(Kim, 등 2003). 국화과의 식물로서 일명황화호(黃花蒿)의 전초를 말하며 1년생 또는 2년생 초본으로 높이는 30−150 cm, 줄기는 원통형이며 어릴적에는 청록색이다(Kim, 등 1999). 청호의 성분으로는 abrotamine, vitamin A, β-bourbonene, caryophyllene, α-pinene, β-pinene, 1,8-cineole,α-thujone 등이 함유되어있다(Kim, 등 1994). 약리작용으로서는해열, 이담, 구충 및 피부진균, 황달, 악창, 탈모의 치료 등에 쓰여지고 있다(Kim, 등 1999; 2002). 본 연구는 상용공정의 기초데이터를 제시하기 위한 방법으로 청호의 추출액 포함된chlorogenic acid, caffeic acid, queretin, aremisinin, vitexin의성분을(Jung 등, 2011), On-line screening high performance liquidchromatography (HPLC)-ABTS
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Antioxidant Activity Analysis of Useful Compounds from Artemisiae Annuae Herba Using On-line Screening HPLC-ABTS + Assay
Journal of Applied Biological Chemistry, 2014Co-Authors: Jin YeulAbstract:Abstract The Antioxidant activity screening identification offive kind compounds in Artemisiae annuae herba with the on-linescreening high performance liquid chromatography (HPLC)ABTS + Assay. The various experimental variables such as theextraction time (h) and extraction solvent composition (%) ofdipping method were investigated efficiently extraction at theroom temperature 25 o C. The results, the highest yield of totalextract amount (0.458 g, 15.250%) was obtained by dippingmethod with 100% water and extraction time to 3 h. And the on-line screening HPLC-ABTS + Assay method was rapid and efficientto search for bioactivity from natural products.Keywords analysis · annuae herba · artemisiae · identification ·on-line screening high performance liquid chromatography청호(Artemisiae Annuae Herba 이하 AAH)는 널리 한국, 일본,중국 등에 널리 분포되어 있으며 향이 강하고 독특하며 대부분약재로 사용되고 있다(Kim, 등 2003). 국화과의 식물로서 일명황화호(黃花蒿)의 전초를 말하며 1년생 또는 2년생 초본으로 높이는 30−150 cm, 줄기는 원통형이며 어릴적에는 청록색이다(Kim, 등 1999). 청호의 성분으로는 abrotamine, vitamin A, β-bourbonene, caryophyllene, α-pinene, β-pinene, 1,8-cineole,α-thujone 등이 함유되어있다(Kim, 등 1994). 약리작용으로서는해열, 이담, 구충 및 피부진균, 황달, 악창, 탈모의 치료 등에 쓰여지고 있다(Kim, 등 1999; 2002). 본 연구는 상용공정의 기초데이터를 제시하기 위한 방법으로 청호의 추출액 포함된chlorogenic acid, caffeic acid, queretin, aremisinin, vitexin의성분을(Jung 등, 2011), On-line screening high performance liquidchromatography (HPLC)-ABTS
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isolation and bioactivity analysis of ethyl acetate extract from acer tegmentosum using in vitro Assay and on line screening hplc ABTS system
Journal of Automated Methods & Management in Chemistry, 2014Co-Authors: Nayoung Song, You Chang Oh, Jin YeulAbstract:The Acer tegmentosum (3 kg) was extracted using hot water, and the freeze-dried extract powder was partitioned successively using dichloromethane (DCM), ethyl acetate (EA), butyl alcohol (n-BuOH), and water. From the EA extract fraction (1.24 g), five phenolic compounds were isolated by the silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatography. Based on spectroscopic methods such as 1H-NMR, 13C-NMR, and LC/MS the chemical structures of the compounds were confirmed as feniculin (1), avicularin (2), (+)-catechin (3), (−)-epicatechin (4), and 6′-O-galloyl salidroside (5). Moreover, a rapid on-line screening HPLC-ABTS+ system for individual bioactivity of the EA-soluble fraction (five phenolic compounds) was developed. The results indicated that compounds 1 and 2 were first isolated from the A. tegmentosum. The anti-inflammatory activities and on-line screening HPLC-ABTS+ Assay method of these compounds in LPS-stimulated murine macrophages were rapid and efficient for the investigation of bioactivity of A. tegmentosum.
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extraction and bioactivity analysis of major flavones compounds from scutellaria baicalensis using in vitro Assay and online screening hplc ABTS system
Journal of Automated Methods & Management in Chemistry, 2014Co-Authors: Pil Mun Jung, You Chang Oh, Nayoung Song, Jin YeulAbstract:The extraction efficiency of a number of solvent compositions for the improvement of bioactive compounds yield from S. baicalensis has been investigated. Also, free radical scavengers in the glycoside baicalin (BG), wogonoside (WG), aglycon baicalein (B), and wogonin (W) compounds of S. baicalensis were screened, identified, and quantified using coupled offline ABTS and online screening HPLC-ABTS Assay. Increasing ethanol content fractions resulted in decreased extract yield of bioactive compounds. In this case, the best yield of 37.01 mg/g in BG, WG, B, and W compounds was obtained by a dipping method with an extraction time of 4 h. In addition, the yield (43.05%) and IC50 (34.04 μg/mL) determined through ABTS Assay of the 60% aqueous ethanol extract were the most satisfactory of all solvent solutions tested. This result shows that an online screening HPLC-ABTS Assay can be a powerful technique for the rapid characterization of bioactivity compounds in plant extracts. Moreover, their anti-inflammatory activities were evaluated via analyzed inhibitory effect on NO and inflammatory cytokine production. Furthermore, WG and W exhibited the strong inhibitory effects on inflammatory mediator production including NO, IL-6, and IL-1β in LPS-stimulated RAW 264.7 macrophages.
Honggao Xu - One of the best experts on this subject based on the ideXlab platform.
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subcritical water extraction and antioxidant activity evaluation with on line hplc ABTS Assay of phenolic compounds from marigold tagetes erecta l flower residues
Journal of Food Science and Technology-mysore, 2014Co-Authors: Honggao Xu, Weiyou Wang, Junping Jiang, Fang YuanAbstract:Subcritical water extraction (SWE) of phenolics was investigated from marigold (Tagetes erecta L.) flower residues. The total phenolics content (TPC), total flavonoids content (TFC) and antioxidant capacities of extracts were determined, furthermore, antioxidant activities of individual compounds were evaluated with on-line HPLC–ABTS•+ system. The optimum SWE time was 45 min, solid-to-liquid ratio was 1:50, and the highest TPC and TFC were obtained at 220 °C respectively. The effect of SWE temperature on TPC and TFC was significant (p < 0.05), and TPC was ranged from 28.42 ± 0.94 to 124.27 ± 1.94 (mg GAE/g), and TFC ranged from 34.21 ± 0.36 to 133.22 ± 1.57 (mg GAE/g) between 80 and 220 °C. On-line HPLC–ABTS•+ profiles revealed that quercetagetin from SWE at 200 °C had nearly twofold radical scavenging activities than that by leaching extraction.
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subcritical water extraction of phenolic compounds from pomegranate punica granatum l seed residues and investigation into their antioxidant activities with hplc ABTS Assay
Food and Bioproducts Processing, 2012Co-Authors: Li He, Honggao Xu, Fang Yuan, Xiaofei Zhang, Chao Xu, želiko Knez, Zoran NovakAbstract:Abstract Subcritical water extraction (SWE) of phenolic compounds from pomegranate seed residues (PSR) was performed. Total phenolic content (TPC) and antioxidant capacities of the extracts obtained at different temperatures were determined, and the individual antioxidant capacities were evaluated by coupling high performance liquid chromatography with ABTS radical reaction system (HPLC–ABTS +). The results showed that the optimum extraction time was 30 min, solid to water ratio was 1:40, and the highest TPC was obtained at 220 °C. The effect of extraction temperature on TPC was significant (p + profiles revealed that nine compounds had antioxidant activity. Furthermore, the formation of Maillard reaction products during SWE was investigated, and the content of 5-hydroxymethylfurfural (5-HMF) was determined. The comparative study indicated that SWE was a promising technique for preparation of PSR phenolics.
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supercritical co2 extraction of oleoresin from marigold tagetes erecta l flowers and determination of its antioxidant components with online hplc ABTS Assay
Journal of the Science of Food and Agriculture, 2011Co-Authors: Ying Gong, Honggao Xu, Szabina Plander, Bela SimandiAbstract:BACKGROUND: Marigold is a traditional medicine herb which shows good pharmacological activity in many aspects. It is very important to obtain and investigate the specific bioactive compounds from marigold. The objective of the study was to extract the oleoresin from marigold with supercritical CO2 (SC-CO2) at different pressures and temperatures, detect the fatty acid composition by gas chromatography–mass spectrometry and investigate the antioxidative components in the extracts by combined online high-performance liquid chromatography-2,2-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid (HPLC-ABTS•+) post-column Assay and HPLC-tandem mass spectrometry. RESULTS: For the pressure range (20–40 MPa) and temperature range (30–70 °C), 30 MPa/70 °C gave the highest yield of oleoresin (58.9 g kg−1). The dominant fatty acids of marigold flower oleoresin were linoleic acid (>26.41%), palmitic acid (>24.22%) and oleinic acid (>20.12%). Significant effects of the extraction pressure and temperature on the antioxidant activity were observed (P < 0.05). Lutein esters, α-tocopherol, β-tocopherol, γ-tocopherol and δ-tocopherol were the dominant antioxidant compounds in the extracts. CONCLUSION: The study has shown that the yield and total antioxidant activity of the marigold extracts were affected by the pressure and temperature of SC-CO2, and that online HPLC technique could be used as an efficient and rapid method for separation and identification of bioactive compounds from a complex mixture. Copyright © 2011 Society of Chemical Industry
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identification of phenolic compounds from pomegranate punica granatum l seed residues and investigation into their antioxidant capacities by hplc ABTS Assay
Food Research International, 2011Co-Authors: Li He, Honggao Xu, Wenhao He, Fang YuanAbstract:Abstract In this study, phenolic compounds were extracted and isolated from pomegranate seed residue (PSR). Phytochemicals and antioxidant capacity of extracts from PSR were firstly investigated. Total phenolic (TP) and proanthocyanidin (PC) contents of the extracts were determined as 2427.90 and 505.63 mg catechin equivalent of 100 g dry weight respectively. To evaluate the antioxidant capacity of individual compounds, on line Assay of coupling high performance liquid chromatographic separation with ABTS free radical reaction system (HPLC–ABTS + ) was carried out. 17 compounds in PSR extracts were detected with antioxidant capacity, and HPLC associated with electrospray ionization mass spectrometry (HPLC–ESI–MS) was used to identify them. The main phenolics in PSR identified were flavol-3-ols, phenolic acids, flavonoid glycosides, and hydrolysable tannin. The results showed that PSR contained some amount of antioxidant compounds, and the HPLC–ABTS + on line method was fast, sensitive and effective.
Nicoletta Pellegrini - One of the best experts on this subject based on the ideXlab platform.
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Application of the 2,2‘-Azinobis(3-ethylbenzothiazoline-6-sulfonic acid) Radical Cation Assay to a Flow Injection System for the Evaluation of Antioxidant Activity of Some Pure Compounds and Beverages
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nicoletta Pellegrini, Barbara Colombi, Marta Bianchi, Furio BrighentiAbstract:The 2,2‘-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) Assay was adapted to a flow injection (FI) system to obtain a sensitive and rapid technique for the monitoring of antioxidant activity of pure compounds and complex matrixes, such as beverages and food extracts. The FI system includes a HPLC pump that flows the mobile phase (a solution of ABTS•+ in ethanol) through a 20 μL loop injector, a single bead string reactor filled with acid-washed silanized beads, a delay coil and a photodiode array UV−visible detector. The technique was very sensitive, with limits of detection and of quantification of 4.14 and 9.29 μmol of Trolox/L, respectively, and demonstrated high repeatability and reproducibility. The proposed technique was then applied to the evaluation of the antioxidant activity of some pure compounds, demonstrating good agreement with published data obtained by the original spectrophotometric ABTS•+ Assay. Finally, the total antioxidant activity of 10 beverages was determi...
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application of the 2 2 azinobis 3 ethylbenzothiazoline 6 sulfonic acid radical cation Assay to a flow injection system for the evaluation of antioxidant activity of some pure compounds and beverages
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nicoletta Pellegrini, Barbara Colombi, Marta Bianchi, Furio BrighentiAbstract:The 2,2‘-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) Assay was adapted to a flow injection (FI) system to obtain a sensitive and rapid technique for the monitoring of antioxidant activity of pure compounds and complex matrixes, such as beverages and food extracts. The FI system includes a HPLC pump that flows the mobile phase (a solution of ABTS•+ in ethanol) through a 20 μL loop injector, a single bead string reactor filled with acid-washed silanized beads, a delay coil and a photodiode array UV−visible detector. The technique was very sensitive, with limits of detection and of quantification of 4.14 and 9.29 μmol of Trolox/L, respectively, and demonstrated high repeatability and reproducibility. The proposed technique was then applied to the evaluation of the antioxidant activity of some pure compounds, demonstrating good agreement with published data obtained by the original spectrophotometric ABTS•+ Assay. Finally, the total antioxidant activity of 10 beverages was determi...
