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Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels
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作者 Rui Yu Zhensheng Shen +6 位作者 Yanan Liu Chengxiang Shi Juncong Qu Lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期104-109,共6页
Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin... Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil. 展开更多
关键词 High-density fuel BIOFUEL Hydrogenation ALKYLATION Lignin phenolics
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Qualitative and quantitative analysis of characteristic free and bound phenolics in three colored quinoas
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作者 Jianxin Song Dezhi Gao Xiaodong Wang 《Journal of Polyphenols》 2024年第2期78-86,共9页
Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound ... Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound phenolics in three colored quinoas including WQ(white quinoa),RQ(red quinoa)and BQ(black quinoa)were investigated.Result showed a total of 14 phenolics both acted as free and bound form were analyzed in three colored quinoas(WQ,RQ and BQ).Gallic acid,vanillic acid,epicatechin,p-coumaric acid and quercetin existed both as free and bound forms were common phenolics in quinoas.The highest total free phenolics(238.10 mg/kg)and bound phenolics(3377.75 mg/kg)were presented in WQ and RQ,respectively.It indicated WQ and RQ were respectively good source of free and bound phenolics.Moreover,characteristic free and bound phenolics in three colored quinoas could be well analyzed by principal component analysis(PCA),indicating it was an effective and reliable method in distinguishing three colored quinoas based on their characteristic free and bound phenolics,respectively. 展开更多
关键词 QUINOA free phenolics bound phenolics PCA
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The hypoglycemic potential of phenolics from functional foods and their mechanisms 被引量:2
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作者 Oksana Golovinskaia Chin-Kun Wang 《Food Science and Human Wellness》 SCIE CSCD 2023年第4期986-1007,共22页
Long-term postprandial hyperglycemia is a primary risk factor for developing chronic metabolic diseases such as obesity,type 2 diabetes,and cardiovascular disease.Chronic hyperglycemia induces the glycation of protein... Long-term postprandial hyperglycemia is a primary risk factor for developing chronic metabolic diseases such as obesity,type 2 diabetes,and cardiovascular disease.Chronic hyperglycemia induces the glycation of proteins,oxidative stress,inflammation and increases plasma insulin and lipid concentrations.Insulin resistance is the primary cause of postprandial excursions of blood glucose and lipids.Hyperglycemia can be treated by lowering dietary carbohydrates intake,digestion,and absorption.Various functional foods improve glucose metabolism by increasing insulin sensitivity and inhibitingα-glucosidase in the small intestine.Natural phytochemicals,especially active phenolics are good antioxidants and show anti-inflammatory action and regulate blood glucose.This review aimed to report on hypoglycemic properties of active phenolics from functional foods and their proposed anti-diabetic mechanisms.Nevertheless,further clinical trials are required to confirm the bioavailability,safety,and efficacy of phenolics,especially the dosage and duration of treatment,to avoid adverse effects and give better dietary recommendations. 展开更多
关键词 phenolics Functional foods HYPOGLYCEMIA Insulin resistance Insulin secretion
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Physicochemical and Biochemical Characterization, Total Phenolic and Energy Value from Bulbs of Different Onion (Allium cepa L.) Varieties in Senegal
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作者 Ndeye Adiara Ndiaye Lahat Niang +1 位作者 Modou Dieng Ndeye Coumba Kane Touré 《Food and Nutrition Sciences》 CAS 2024年第2期129-139,共11页
The purpose of this study is to investigate the physicochemical properties of some local varieties of onion (Allium cepa L.) and compare them with an imported variety, all collected in May 2021. Proteins, reducing sug... The purpose of this study is to investigate the physicochemical properties of some local varieties of onion (Allium cepa L.) and compare them with an imported variety, all collected in May 2021. Proteins, reducing sugars, lipids, and polyphenol content were estimated according to the AFNOR standardized methods. The determination of calcium, magnesium, iron, sodium, potassium and phosphorus was performed by atomic absorption spectrophotometer coupled with a CCD detector. The results highlighted an average acidity of 0.377% ± 0.002% lower than the value of the imported variety which is 0.520% ± 0.001%. Local varieties have a pH ranging from 6.35 ± 0.003 to 6.42 ± 0.004, while the variety has a pH of 6.36 ± 0.003. The ash and dry matter contents vary respectively from 4.788% ± 0.004% to 8.253% ± 0.003% and 7.945% ± 0.021% to 11.945% ± 0.007% for the local varieties. Moreover, the imported one has ash and dry matter contents of 5.175% ± 0.007% and 10.035% ± 0.021% respectively. The results show that the protein, reducing sugar and lipid contents in the local onion varieties vary respectively from 2.815 ± 0.000 to 15.634 ± 0.001 g·100 g<sup>-1</sup>;4.691 ± 0.001 to 12.596 ± 0.002 g·100 g<sup>-1</sup> and 0.006 ± 0.001 to 0.050 ± 0.057 g·100 g<sup>-1</sup>. Furthermore, the imported variety has a protein, reducing sugar and lipid content of 5.649 ± 0.002;8.565 ± 0.002 g·100 g<sup>-1</sup> and 0.011 ± 0.010 g·100 g<sup>-1</sup> respectively. The maximum levels of total polyphenols are obtained in the imported variety, Bellani and Gandiol, respectively 9.973 ± 0.001, 4.535 ± 0.002, and 3.425 ± 0.006 mg EAG/g of dry matter. The local varieties have a significant calorific intake of between 35.451 ± 0.001 and 112.980 ± 0.003 kcal·100 g<sup>-1</sup> compared to the imported one with an energy value of 56.953 ± 0.001 kcal·100 g<sup>-1</sup> of dry matter. The bulbs of different onion varieties studied have a fairly high content of mineral elements. The potassium content of local varieties is between 502.16 ± 0.06 mg·100 g<sup>-1</sup> and 582.77 ± 0.04 mg·100 g<sup>-1</sup> while the imported variety has a content of 536.62 ± 1.30 mg·100 g<sup>-1</sup>. They note that the local varieties have a better calcium content (249.75 ± 0.07 to 434.20 ± 0.57 mg·100 g<sup>-1</sup>) and magnesium (142.15 ± 0.07 to 162.60 ± 0.42 mg·100 g<sup>-1</sup>) than the imported variety (229.58 ± 0.04 mg·100 g<sup>-1</sup>) except for the varieties White Grano (228.29 ± 0.01 mg·100 g<sup>-1</sup>) and Rouge Amposta (117.00 ± 0.42 mg·100 g<sup>-1</sup>) respectively. These results reveal that Gandiol, Dayo and Orient F1 are nutritionally found better due to their higher antioxidant property, proteins, carbohydrates, and reducing sugar and should be included in diets to supplement our daily allowance needed by the body. 展开更多
关键词 Allium cepa L. Characterization PHYSICOCHEMICAL BIOCHEMISTRY Total phenolic
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Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance
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作者 Wenjie Xu Wenda Song +4 位作者 Xianfeng Jia Cheng Ma Jitong Wang Wenming Qiao Licheng Ling 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期192-199,共8页
Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,s... Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications. 展开更多
关键词 NANO-SILICA Carbonfiber phenolic aerogel Insulation Ablation
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Quantification of Total Phenols, Total Flavonoids, Total Anthocyanins and Evaluation of Antioxidant and Antiradical Activities of Detarium Senegalense Extracts from Chad
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作者 Salomon Madjitoloum Betoloum Séverin Mbaihougadobe +3 位作者 Abel Mbaiogaou Djibrine Adoum Oumar Mbaindiguim Dagoto Yaya Mahmout 《Advances in Biological Chemistry》 CAS 2024年第1期1-15,共15页
The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity o... The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. . 展开更多
关键词 Total phenols Total Flavonoids Total Anthocyanins Antioxidant and Anti-Radical Activities Detarium Senegalense CHAD
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Distribution of antioxidants and phenolic compounds in flour milling fractions from hard red winter wheat
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作者 Lauren Renee Brewer Jittawan Kubola +1 位作者 Sirithon Siriamornpun Yong-Cheng Shi 《Grain & Oil Science and Technology》 CAS 2024年第2期71-78,共8页
Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not bee... Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not been well documented in terms of conventional milling by-product streams.In this study,multiple analytical methods were used to investigate antioxidant activity and phenolic compound compositions of hard red winter wheat(whole ground wheat),the parts of a wheat kernel(bran,flour,germ),and wheat by-product streams(mill feed,red dog,shorts)for the first time.For each mill stream,phenolic compounds(total,flavonoid,and anthocyanin contents)were determined and antioxidant activities were evaluated with 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical-scavenging activity,ferric reducing/antioxidant power(FRAP),and total antioxidant capacity assays.Significant differences(P<0.05)were observed in phenolic concentrations among fractions of bran,flour,and germ milled from the same kernels and noted that germ accounts for the majority of antioxidant properties,whereas bran contains a substantial portion of phenolic compounds and anthocyanins.Mill feed was high in phenolic content(5.29 mg FAE/g),total antioxidant capacity(866 mg/g),and antioxidant activity(up to 75% DPPH inhibition and 20.26μmol FeSO_(4)/g).The comprehensive information on distribution of antioxidants and phenolic compounds provides insights for future human consumption of commonly produced co-products from flour milling,and for selecting and using different milling fractions to make foods with improved nutritional properties. 展开更多
关键词 Wheat Milling streams ANTIOXIDANTS phenolic acids Flavonoid ANTHOCYANIN
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Hollow ZIF-67-derived Co@N-doped carbon nanotubes boosting the hydrogenation of phenolic compounds to alcohols
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作者 Zhihao Guo Jiuxuan Zhang +3 位作者 Lanlan Chen Chaoqun Fan Hong Jiang Rizhi Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期157-166,共10页
The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named... The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named Co@NCNTs,were designed and constructed by direct pyrolysis of hollow ZIF-67(HZIF-67)under H_(2)/Ar atmosphere.The evolution of the catalyst surface from the shell layer assembled by ZIF-67-derived particles to the in situ-grown hollow nitrogen-doped carbon nanotubes(NCNTs)with certain length and density is achieved by adjusting the pyrolysis atmosphere and temperature.Due to the synergistic effects of in situ-formed hollow NCNTs,well-dispersed Co nanoparticles,and intact carbon matrix,the as-prepared Co@NCNTs-0.10-450 catalyst exhibits superior catalytic performance in the hydrogenation of phenolic compounds to alcohols.The turnover frequency value of Co@NCNTs-0.10-450is 3.52 h^(-1),5.9 times higher than that of Co@NCNTs-0.40-450 and 4.5 times higher than that of Co@NCNTs-0.10-550,exceeding most previously reported non-noble metal catalysts.Our findings provide new insights into the development of non-precious metal,efficient,and cost-effective metal-organic framework-derived catalysts for the hydrogenation of phenolic compounds to alcohols. 展开更多
关键词 phenolic compounds Hollow ZIF-67 pyrolysis Nitrogen-doped carbon nanotubes Reduction Multiphase reaction Catalysis
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Screening for Antioxidant Phenolic Compounds from Polygonum capitatum
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作者 Yan LIN 《Medicinal Plant》 2024年第4期1-3,10,共4页
[Objectives]To discover antioxidant natural products from the famous Hmong medicinal plant Polygonum capitatum.[Methods]The antioxidant activities of the isolated components were evaluated by ABTS and DPPH assays.[Res... [Objectives]To discover antioxidant natural products from the famous Hmong medicinal plant Polygonum capitatum.[Methods]The antioxidant activities of the isolated components were evaluated by ABTS and DPPH assays.[Results]A total of 27 free phenolics were isolated form P.capitatum.Then the in vitro antioxidant potential of these components was evaluated according to the DPPH and ABTS radical scavenging assays.Among them,five compounds(13,14,17,23,and 25)showed most significant ABTS radical-scavenging activity(IC 50 values of 3.81-15.09μg/mL).And 12 components(1,2,6,7,9,12,13,14,16,17,23,and 25)showed notable radical scavenging activity against DPPH(inhibition rates>88%).[Conclusions]Most of the above bioactive compounds were reported for the first time. 展开更多
关键词 Polygonum capitatum phenolic compounds Antioxidant activity
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Mechanism of action of Balanophora involucrata polyphenolic compounds in the treatment of myocardial injury based on network pharmacology and molecular docking techniques
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作者 Shipeng Duan Ting Gao +4 位作者 Feifei Li Xuehan Li Haojun Shen Fang Wang Xiaoshu Zhang 《Journal of Polyphenols》 2024年第2期45-55,共11页
The objective of this work was to investigate the mechanism of action of Balanophora involucrata polyphenolic compounds in the treatment of myocardial injury.In the present study,Balanophora involucrata was extracted ... The objective of this work was to investigate the mechanism of action of Balanophora involucrata polyphenolic compounds in the treatment of myocardial injury.In the present study,Balanophora involucrata was extracted by refluxing 75%of ethanol.The obtained extract was extracted with petroleum ether,ethyl acetate and n-butanol respectively.And the ethyl acetate layer was separated.The extract was prepared by silica gel column chromatography,sephadex LH-20 elution and thin layer chromatography.After that,the Swiss target prediction database was utilized to obtain the targets of Balanophora involucrata,and the Genecards,OMIM and TTD databases were used to predict and screen the targets of Balanophora involucrata for the treatment of myocardial injury.The active ingredient-target network was constructed using Cytoscape software,and the PPI network was mapped using String database and Cytoscape software.GO bioprocess enrichment analysis and KEGG pathway enrichment analysis were performed by Metascape software to predict the mechanism of action.Molecular docking was performed in Discovery Studio 2016 client software to verify the binding of Balanophora involucrata polyphenols to key targets.In this study,six polyphenolic compounds were isolated from Balanophora involucrata.By GO enrichment analysis,1614 biological processes(BP),127 cellular compositions(CC),and 215 molecular functions(MF)were obtained;a total of 155 cross-targets were involved in the KEGG enrichment analysis.The PPI network showed that quercetin was the main active component of polyphenolic compounds against myocardial injury and that AKT1,EGFR,STAT3,SRC,ESR1,MMP9,HSP90AA1 and other related signals were associated with myocardial injury treatment.Finally,the multi-component-multi-target-multi-pathway action of Balanophora involucrata was concluded,which provided new ideas and methods for further research on the mechanism of action of Balanophora involucrata in myocardial injury. 展开更多
关键词 Balanophora involucrata myocardial injury phenolic compounds network pharmacology molecular docking
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Evaluation of Phytochemical Analysis and Total Phenol Content of Proso Millet and Barnyard Millet
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作者 Deepa Priya Ramadoss Kirubanandan Shanmugam 《Proceedings of Anticancer Research》 2024年第2期13-19,共7页
Whole grains of proso and barnyard millets were sequentially extracted using different solvents(hexane,chloroform,ethyl acetate,and methanol).Phytochemical analysis was performed qualitatively,and the total phenolic c... Whole grains of proso and barnyard millets were sequentially extracted using different solvents(hexane,chloroform,ethyl acetate,and methanol).Phytochemical analysis was performed qualitatively,and the total phenolic content in the extracts of proso and barnyard millets was quantified.Alkaloids and cardiac glycosides were identified in all solvent extracts of both millets.Anthraquinone and glycosides yielded negative results in all solvent extracts of both millets.Among all the solvent extracts,methanol extracts of proso and barnyard millets showed the presence of major compounds such as flavonoids,terpenoids,amino acids,tannins,and phenolics compounds.The maximum amount of phenols was found in methanolic extracts of proso and barnyard millets(0.669±0.003 and 0.625±0.003),followed by the chloroform extract of proso and barnyard millets(0.284±0.002 and 0.257±0.003).The minimum amount of phenolics was found in the acetone extract of proso and barnyard millets.The methanol extract of both millets showed the presence of major compounds with high phenolic content. 展开更多
关键词 Proso millet Barnyard millet Sequential solvent extraction Phytochemical analysis Total phenolic content
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In vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah 被引量:11
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作者 M Amzad Hossain Muhammad Dawood Shah +1 位作者 Charles Gnanaraj Muhammad Iqbal 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第9期717-721,共5页
Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dr... Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane.ethyl acetate,chloroform,butanol and aqueous methanol.The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) method.Results:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil.The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract】ethyl acetate extract】chloroform】butanol】hexane extract also the antioxidant activity was not detected in essential oil.Conclusions:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract.Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant. 展开更多
关键词 Total phenolics FLAVONOIDS Antioxidant aotivity Essential oil EXTRACTS Tetrastigma
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Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS 被引量:9
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作者 Sunil Kumar Awantika Singh Brijesh Kumar 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第4期214-222,共9页
Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid... Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P.niruri. 展开更多
关键词 PHYLLANTHUS SPECIES HPLC-ESI-QTOF-MS/MS phenolics
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Correlation Between Antioxidation and the Content of Total Phenolics and Anthocyanin in Black Soybean Accessions 被引量:20
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作者 XU Jin-rui ZHANG Ming-wei +4 位作者 LIU xing-hua LIU Zhang-xiong ZHANG Rui-fen SUN Ling QIu Li-juan 《Agricultural Sciences in China》 CAS CSCD 2007年第2期150-158,共9页
The objective of this study was to investigate the correlations between antioxidations and the contents of the total phenolics and anthocyanin in 127 accessions of black soybean. A T-test, a fast clustering procedure,... The objective of this study was to investigate the correlations between antioxidations and the contents of the total phenolics and anthocyanin in 127 accessions of black soybean. A T-test, a fast clustering procedure, and a correlation coefficient analysis were used for experimentation. The variation ranges of the total antioxidant capacity (TAC), the total phenolics, and anthocyanin contents in 127 black soybean accessions were 0.44-3.56, 7.05-74.82, and 0.22-1.87 mg g-l, respectively, displaying significant genotype differences. The major differences in TAC, the total phenolics, and the anthocyanin contents existed among various types of accessions from geographical regions. The differences between the accessions from black and yellow soybeans, spring and autumn, summer and autumn, Dongbeichun and Nanfangchun, Dongbeichun and Nanfangxia, Beifangchun and Nanfangchun, and Beifangchun and Nanfangxia were significant at 0.01 or 0.05 levels, respectively. The general tendency was that the TAC, the total phenolics, and the anthocyanin contents of Beifangchun accessions were higher than that of Dongbeichun ones, while that of Nanfangchun accessions were the worst. 127 black soybean accessions could be clustered into 6 clusters, which consisted of 3, 24, 20, 31, 37, and 12 accessions, respectively. The most significant (P 〈 0.01) correlations existed respectively between the TAC and the total showed that the total substances phenolics content, and the TAC and the anthocyanin content of black soybean. The results phenolics and anthocyanin in black soybean seed coat were the important antioxidation 展开更多
关键词 seed coat of black soybean ANTIOXIDATION total phenolics content anthocyanin content CORRELATION
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Gradient nanoporous phenolics as substrates for high-flux nanofiltration membranes by layer-by-layer assembly of polyelectrolytes 被引量:3
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作者 Yazhi Yang Qianqian Lan Yong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期114-121,共8页
Thin film composite(TFC) membranes represent a highly promising platform for efficient nanofiltration(NF)processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein,highly... Thin film composite(TFC) membranes represent a highly promising platform for efficient nanofiltration(NF)processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein,highly permeable gradient phenolic membranes with tight selectivity are used as substrates to prepare TFC membranes with high permeances by the layer-by-layer assembly method. The negatively charged phenolic substrates are alternately assembled with polycation polyethylenimine(PEI) and polyanion poly(acrylic acid)(PAA)as a result of electrostatic interactions, forming thin and compact PEI/PAA layers tightly attached to the substrate surface. Benefiting from the high permeances and tight surface pores of the gradient nanoporous structures of the substrates, the produced PEI/PAA membranes exhibit a permeance up to 506 L? m-2?h-1?MPa-1, which is ~2–10 times higher than that of other membranes with similar rejections. The PEI/PAA membranes are capable of retaining N 96.1% of negatively charged dyes following the mechanism of electrostatic repulsion. We demonstrate that the membranes can also separate positively and neutrally charged dyes from water via other mechanisms.This work opens a new avenue for the design and preparation of high-flux NF membranes, which is also applicable to enhance the permeance of other TFC membranes. 展开更多
关键词 NANOFILTRATION membrane POLYELECTROLYTE Layer-by-layer assembly High PERMEANCE GRADIENT phenolIC
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Evaluation of Standards and Interfering Compounds in the Determination of Phenolics by Folin-Ciocalteu Assay Method for Effective Bioprocessing of Biomass 被引量:2
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作者 Krishna Prasad Bastola Yadhu Nath Guragain +1 位作者 Vamsi Bhadriraju Praveen Venkata Vadlani 《American Journal of Analytical Chemistry》 2017年第6期416-431,共16页
Folin Ciocalteu (F-C) assay is the most widely used and convenient method to determine the total phenolics content in foods, herbs, and other plant extracts. Different phenolics standards such as gallic acid, ferulic ... Folin Ciocalteu (F-C) assay is the most widely used and convenient method to determine the total phenolics content in foods, herbs, and other plant extracts. Different phenolics standards such as gallic acid, ferulic acid, chlorogenic acid, catechol, and vanillic acid have been used for calibration curves in this assay method. Comparison of these standards, in single or combination of two or more, for more accurate determination of phenolics has not been reported so far. This study tested five single phenolics and seven combinations of mixed phenolic standards to evaluate the optimal standards for F-C method. The different standards were tested to calculate the phenolic content in three known test solutions. We also evaluated interference effect of various compounds in phenolics estimation by F-C method that is usually present in the lignocellulosic biomass-derived sugar solution, and in food products along with phenolics. Finally, the optimal standards with five phenolics were used for the determination of phenolics in alkali pretreated biomass extract. The results indicated that gallic acid was the best standard among the single phenolic compounds and five phenolic compounds solution was the best standard among the mixed phenolic solutions. The presence of glucose, HMF, furfural, and vitamin-B12 did not interfere in phenolic determination;whereas ascorbic acid, tyrosine, formic acid, and acetic acid strongly interfered the results. The results also showed that biomass pelleting process did not affect the generation of phenolics in alkali pretreatment extract. 展开更多
关键词 phenolics FOLIN-CIOCALTEU Interferents BIOMASS
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Chemical Composition, Phenolics, Anthocyanins Concentration and Antioxidant Activity of Ten Wild Edible Plants 被引量:2
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作者 Khalil I. Ereifej Hao Feng +4 位作者 Taha Rababah Ali Almajwal Muhammad Alu’datt Sana I. Gammoh Layal I. Oweis 《Food and Nutrition Sciences》 2015年第7期581-590,共10页
Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was ... Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was the highest among the plants. Ruta chalepensis had high levels of fat and carbohydrates (4.2% and 51.7%, respectively), but had the lowest level of ash (8.7%). Mineral concentrations varied and found to have appreciable amounts of Ca, Na, K, Cu, Fe, Mg, Mn, Zn and P. Total phenolic ranged from 163.1 (Tetragonolobus palaestinus) to 1328.8 mg GAE/100g (Ruta chalepensis). Anthocyanins ranged between 18.1 (Gundelia tournefortii) and 100.1 mg/100g (Rumex acetosella). These plants differed in free radical scavenging activity. It was concluded that these plants could be considered as natural sources for antioxidants and valuable natural resources as a new addition to the diet of inhabitants. 展开更多
关键词 WILD EDIBLE Plants Total phenolics Anthocyanins ANTIOXIDANT Activity DPPH
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Studies on Changes of Phenolics in the Apple Fruit Peel in Response to Light Intensity 被引量:1
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作者 HAOYan-yan HUANGWei-dong ZHANGWen-he 《Agricultural Sciences in China》 CAS CSCD 2004年第2期108-115,共8页
Fruits from 9-year-old apple trees (Malus domestic Borkh. cv. Fuji) were wrapped by two-layerbag in middle of June, and bags were removed in middle of September. The bag-removed treatmentwas performed in following thr... Fruits from 9-year-old apple trees (Malus domestic Borkh. cv. Fuji) were wrapped by two-layerbag in middle of June, and bags were removed in middle of September. The bag-removed treatmentwas performed in following three ways: once-removing all inner and outer bags; twice-removingbag (removing inner bag 3 d after removing outer bag); dipping 5 s in 1 mM salicylic acid (SA)after once-removing all bags. Changes of phenolic compounds in fruit peel in response to lightenvironment were studied before or after removing bag. The results showed that the baggedtreatment could significantly decrease the contents of UV (ultraviolet)absorbing compounds,rutin and anthocyanins of the fruit peel, but increased chlorogenic acid level. After removalof bag, the level of SA and quercetin in the fruit peel appeared peak 1 d after bag-removed,except that quercetin was decreased in SA-treated fruits. UV absorbing compounds, anthocyaninsand rutin were kept increasing all along after the removal of bag, except that chlorogenic acidwas decreased during being retained inner bag in the treatment of twice removing bag. Thepositive correlations existed between changes of UV absorbing compounds and changes ofanthocyanins or rutin. It was suggested that light played an important role in phenolicsmetabolism. 展开更多
关键词 BAG Fruit peel phenolics SA
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Phenolics,tannins,flavonoids and anthocyanins contents influenced antioxidant and anticancer activities of Rubus fruits from Western Ghats,India 被引量:4
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作者 Kasipandi Muniyandi Elizabeth George +4 位作者 Saikumar Sathyanarayanan Blassan P.George Heidi Abrahamse Suman Thamburaj Parimelazhagan Thangaraj 《Food Science and Human Wellness》 SCIE 2019年第1期73-81,共9页
Rubus fruits are rich in nutrition with a wide range of phytochemical and consumed by humans,but many of its wild varieties are not commercially useful.Phytochemical exploration of these wild fruits could improve the ... Rubus fruits are rich in nutrition with a wide range of phytochemical and consumed by humans,but many of its wild varieties are not commercially useful.Phytochemical exploration of these wild fruits could improve the commercial usage of these Rubus species.This study focuses to analyze the phytochemical,antioxidant and cytotoxicity of three wild Rubus ellipticus,R.niveus and R.fairholmianus fruits comparatively,which has not revealed.The in vitro antioxidant studies indicated the ethyl acetate and methanol extracts of studied Rubus species competent in scavenging different stable and generated radical.The correlation and regression analysis also statistically supported the contents in the extracts could act against various radicals.Correlation between phytochemical constituent and radical scavenging activity found to be highly positive.The results acquired from this investigation revealed that they are equally competent and could be recommended as dietary supplements or as nutraceuticals. 展开更多
关键词 ANTICANCER ANTIOXIDANT FLAVONOIDS NUTRACEUTICALS phenolics
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Role of phenolics as antioxidants,biomolecule protectors and as anti-diabetic factors-Evaluation on bark and empty pods of Acacia auriculiformis 被引量:1
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作者 Arumugam Sathya Perumal Siddhuraju 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第10期757-765,共9页
Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis (A.auriculiformis).Methods:Sa... Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis (A.auriculiformis).Methods:Samples of bark and empty pod extracts were analyzed for bioactives(phenolics,flavonoids and proanthocyanidins) and subjected to free radical scavenging activity on DPPH<sup>*</sup>,ABTS<sup>?</sup>,OH<sup>?</sup>,O<sub>2</sub><sup>*</sup>,and NO along with the determination of reducing power, iron chelating activity and peroxidation inhibition.Defensive action of extracts on biomolecules and cell membranes were evaluated by DNA nicking assay and haemolysis inhibition assay respectively,α-amylase andα-glucosidase inhibitory potentials were also determined. Results:All the bioactives analyzed were higher in bark(B) than empty pods(EP)[TPC:B (574.51±16.11);EP(96.80±3.45) mg GAE/g.TFC:B(94.71±7.65);EP(24(?)87±20.45) mg RE/g. Proanthocyanidins:B(2.81±0.31);EP(1.25±0.01) mg LE/100 g DM]except flavonoids.Both the extracts showed higher quenching capacity on DPPH and ABTS(DPPH:B(0.21±0.01);EP(1.51±0.17) g extract/g DPPH.ABTS:B(111 519.14±79 340.91);EP(80 232.55±32 894.12) mmol TE/g) with the FRAP of B(84 515.63±3 350.69) and EP(47 940.79±1 257.60) mmol Fe((?))/g.Iron chelation was not observed.In addition,they showed lower quenching activity on OH<sup>?</sup>(B(48.95±1.72);EP(34.94±1.62)%) and equivalent quenching on O<sub>2</sub><sup>?</sup>(B(53.47±3.92);EP(24.41±2.61)%),NO(B(49.04±5.04); EP(51.00±5.13)%),peroxidation inhibition(B(67.50±5.50);EP(55.l±2.3)%) and antihaemolytic potential(B(87.60±6.84)%) towards authentic antioxidant standards.Interestingly,Empty pod extracts are devoid of antihaemolytic activity.Both the extracts showed dose dependent DNA protection.Besides this,bark and empty pod extracts exhibited dual inhibiting potential againstα-amylase andα-glucosidase enzymes.Conclusions:On summarization,it insinuated that both bark and empty pods can be used for the preparation of antioxidant/nutraceutical supplements and in anti-diabetic formulations. 展开更多
关键词 phenolics BARK EMPTY PODS ACACIA auriculiformis Antioxidant activity TypeⅡdiabetes
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