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Synthesis, Characterization and Antioxidative Activity of Lanthanide Complexes with Genistein 被引量:3
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作者 樊娟 申蕊 唐宁 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第S1期25-28,共4页
Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1... Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L. 展开更多
关键词 GENISTEIN lanthanide complexes antioxidative activity synthesis and characterization rare earths
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Effects of chilling tolerance induced by spermidine pretreatment on antioxidative activity,endogenous hormones and ultrastructure of indica-japonica hybrid rice seedlings 被引量:4
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作者 ZENG Yan-hua ZAHNG Yu-ping +4 位作者 XIANG Jing WU Hui CHEN Hui-zhe ZHANG Yi-kai ZHU De-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期295-308,共14页
Spermidine(Spd) is known to be involved in the regulation of plant responses to chilling stress and counteract the adverse effect of stress conditions.Antioxidant activities,endogenous hormones and ultrastructure ch... Spermidine(Spd) is known to be involved in the regulation of plant responses to chilling stress and counteract the adverse effect of stress conditions.Antioxidant activities,endogenous hormones and ultrastructure change under chilling stress were investigated in indica-japonica hybrid rice seedlings.12-d-old seedlings were subjected to exogenous Spd(1 mmol L^(-1)) and then a chilling stress(6℃,4 d) was induced,followed by a subsequent recovery(25℃,4 d).Results showed that malondialdehyde(MDA) and proline content were enhanced significantly,whereas shoot fresh and dry weights decreased during chilling stress and after recovery;chlorophyll content of chilling-stressed seedlings increased slightly but declined after recovery;additionally,total soluble sugar,sucrose,fructose and starch contents increased significantly during chilling stress,and only soluble sugar and fructose contents were observed in increase after recovery;chilling stress-induced increases in superoxide dismutase(SOD),peroxidase(POD) and catalase(CAT) activities,but declined after recovery,and the level of ascorbate peroxidase was lower during chilling stress and after recovery;however,endogenous indole-3-acetic acid(IAA),zeatin riboside(ZR),gibberellic acid(GA_3),and abscisic acid(ABA) levels were induced decreased compared with Spd pretreatment.The microscopic analysis revealed that chilling stress-induced destruction of the chloroplast envelope during chilling stress and increased the number of plastoglobuli along with aberrations in thylakoid membranes after recovery.In contrast,exogenous Spd protected rice seedlings from chilling-induced injuries in terms of lower malondialdehyde,proline and carbohydrates accumulation coupled with increased endogenous hormones metabolism.After recovery,Spd pretreatment chilling-exposed seedlings showed higher activities of antioxidant enzymes and normal physiological function of chloroplasts.These results suggest that Spd could promote effectively chilling tolerance which might be largely attributable to the integrity of cell structure and normal metabolism of endogenous hormones in indica-japonica hybrid rice seedlings. 展开更多
关键词 polyamines chilling stress antioxidative activity endogenous hormones ultrastructure indica-japonica hybrid rice(Oryza sativa L.)
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Synthesis, Characterization and Antioxidative Activity of Lanthanide Complexes with 3,5-Dibenzyloxybenzoyl-2,4-Dihydroxybenzaldehyde-Hydrazone
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作者 张玲 唐宁 +1 位作者 房建国 谭民裕 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第5期595-597,共3页
In order to study the coordination character of the rare earth elements with hydrazones and the antioxidative activity of the ligand and the complexes, 3,5 dibenzyloxybenzoyl 2,4 dihydroxybenzaldehyde hydrazone (H ... In order to study the coordination character of the rare earth elements with hydrazones and the antioxidative activity of the ligand and the complexes, 3,5 dibenzyloxybenzoyl 2,4 dihydroxybenzaldehyde hydrazone (H 2L), a new chelating ligand, and its six lanthanide complexes, Ln (HL)(OAc) 2· n H 2O [Ln=La, Sm, Eu, Gd, Tb, Dy; n =2, 4, 5], were synthesized and characterized on the basis of elemental analyses, IR and 1H NMR spectra, molar conductivity. The results show that the lanthanide ions are coordinated by O, O and N donors of the phenol (Ar OH) without deprotonation, the enol oxygen of the hydrazone group (NCO -) and the azomethine group (CH=N) from the ligand respectively, and by the four carboxylic oxygen from two acetate groups (CH 3COO -) in the bidentate form. The scavenging activity of the ligand and the six lanthanides complexes on the 2,2 Diphenyl 1 picrylhydrazyl (DPPH) free radicals is also evaluated. The results show that both the ligand and the complexes have the scavenging activity on the DPPH radicals, and the scavenging activity of the complexes is better than the ligand. 展开更多
关键词 inorganic chemistry hydrazone complexes CHARACTERIZATION antioxidative activity rare earths
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Antioxidative activity of protein hydrolysates from anchovy
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作者 DING Li-jun LAI Xue-ling LIU Xiao-qing 《Journal of Chemistry and Chemical Engineering》 2008年第6期56-59,65,共5页
Alcalase hydrolyzed protein from Anchovy under controlled condition, and the hydrolysates were rich in active peptides. The peptide content was determined by TCA-biuret method, and amino acid was determined by Ninhydr... Alcalase hydrolyzed protein from Anchovy under controlled condition, and the hydrolysates were rich in active peptides. The peptide content was determined by TCA-biuret method, and amino acid was determined by Ninhydrin. The antioxidative activity of the hydrolysates was investigated by measuring the reducing ability, the inhibition of lipoxygenase activity, and antioxidative ability in linoleic acid oxidation system. The hydrolysates exhibited high antioxidative activity. In addition, the hydrolysates scavenged 58.38% on hydroxyl radical and 46.88% on superoxide radical. 展开更多
关键词 protein hydrolysatey PEPTIDES antioxidative activity free radicals ANCHOVY
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Total Phenolic Content and Antioxidative Activity in Seasoning Protein Hydrolysate as Affected by Pasteurization and Storage
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作者 K. Arunrat S. Siripongvutikom C. Thongraung 《Journal of Food Science and Engineering》 2011年第4期252-262,共11页
Protein hydrolysate prepared from fish and shrimp by-products were used to prepare a seasoning protein hydrolysate (SPH). The effects of pasteurization and storage on total phenolic content (TPC), DPPH radical sca... Protein hydrolysate prepared from fish and shrimp by-products were used to prepare a seasoning protein hydrolysate (SPH). The effects of pasteurization and storage on total phenolic content (TPC), DPPH radical scavenging activity, reducing power, and color of the SPH were investigated. Pasteurization at 90 ℃ for 10 minutes led to a reduction of TPC and DPPH radical scavenging activity and an increase of reducing power of solid fraction of SPH by about 30%, 99%, and 100%, respectively. Consequently it increased TPC DPPH radical scavenging activity, and reducing power of the liquid phase by about 32%, 600%, and 100%, respectively. Storage at 28, 35, or 45 ℃ for 12 weeks altered color values and increased brownness intensity (OD420). The storage led to an apparent increase of the TPC and antioxidative activity of the product. The results indicate the possibility of producing healthy appetizers from protein hydrolysate prepared from by-products of the seafood industry. 展开更多
关键词 Seasoning protein hydrolysate PASTEURIZATION DPPH storage and antioxidative activity.
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Preparation,characterization and antioxidant activity analysis of three Maillard glycosylated bone collagen hydrolysates from chicken,porcine and bovine
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作者 Liwei Qi Hongru Zhang +2 位作者 Yujie Guo Hong Liu Chunhui Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2002-2013,共12页
Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant activity.Maillard glycosylated reacti... Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant activity.Maillard glycosylated reaction is considered as a promising method to enhance the antioxidant activity of peptides.Hence,this research aims at investigating the Maillard glycosylation activity and antioxidant activity of bone collagen hydrolysates from different sources.In this study,3 glycosylated bone collagen hydrolysates were prepared and characterized,and cytotoxicity and antioxidant activity were analyzed and evaluated.The free amino groups loss,browning intensity,and fluorescence intensity of G-Cbcp(glycosylated chicken bone collagen hydrolysates(peptides))were the heaviest,followed by G-Pbcp(glycosylated porcine bone collagen hydrolysates(peptides))and G-Bbcp(glycosylated bovine bone collagen hydrolysates(peptides)).The results of amino acid analysis showed that amino acid composition of different bone collagen hydrolysates was significantly different and the amino acid decreased to different degrees after Maillard glycosylated reaction,which may lead to differences in Maillard glycosylated reaction activity.Furthermore,the 3 glycosylated hydrolysates showed no significant cytotoxicity.The results showed that glycosylation process significantly increased the antioxidant activity of bone collagen hydrolysates,and G-Cbcp showed the strongest antioxidant activity,followed by G-Pbcp and G-Bbcp.Therefore,compared with the bone collagen hydrolysates,3 glycosylated hydrolysates showed significant characteristic and structural changes,and higher antioxidant activity. 展开更多
关键词 Bone collagen hydrolysates Glycosylation reaction Antioxidant activity
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Total Alkaloid Content, Total Phenolic Content, In Vitro Antioxidant Activity, and Preliminary Antiglycemic Potential of the Methanol Extract from Mozambican Wild Fruits of Vangueria infausta
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作者 Paulo Cumbane Angellique Niyragira +1 位作者 Anésia Felicidade Machava Borges Chambal 《Food and Nutrition Sciences》 CAS 2024年第9期905-920,共16页
This study investigated the antioxidant activity and alpha-amylase inhibitory potential of the methanolic extract from Vangueria infausta fruits with the aim of exploring its therapeutic and nutritional applications. ... This study investigated the antioxidant activity and alpha-amylase inhibitory potential of the methanolic extract from Vangueria infausta fruits with the aim of exploring its therapeutic and nutritional applications. Bioactive compounds such as total phenolics (TPC) and total alkaloids (TAC) were analyzed. Antioxidant activity was assessed using the DPPH, ABTS, FRAP, Ferrozine, Phosphomolybdate, and Folin-Ciocalteu methods, while alpha-amylase inhibitory activity was determined using the 3,5-Dinitrosalicylic Acid (DNSA) and 2-chloro-p-nitrophenyl-α-D-maltotrioside (CNPG3) methods. The results revealed significant variations in antioxidant activity across the methods used, with IC50 values ranging from 318.42 to 1255.56 µg/mL. Alpha-amylase inhibition was also significant, with IC50 values ranging from 140.85 to 121.06 µg/mL. The TPC was found to be 95.6 mg of gallic acid equivalent per 100 g of dry powder, and the TAC was 0.188 mg of atropine equivalent per 100 g of dry powder. These findings suggest that Vangueria infausta possesses promising antioxidant and alpha-amylase inhibitory potential, indicating its potential application in antioxidant therapies and in the management of carbohydrate digestion. 展开更多
关键词 Vangueria infausta Antioxidant activity Alpha-Amylase Inhibition TPC TAC
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Antioxidant Activity of Ethyl Acetate Extract of Amomum villosum Lour.
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作者 Ziyan TAN Yanling QIAN +6 位作者 Pingping MENG Dongjing TENG Yanfei QIN Caiqi NONG Suoyi HUANG Ke SUN Tingting HE 《Medicinal Plant》 2024年第5期4-6,共3页
[Objectives]To study the antioxidant activity of the ethyl acetate extract of Amomum villosum Lour.[Methods]The removal rate of chelated iron ions,hydroxyl radicals,superoxide anion free radicals and DPPH free radical... [Objectives]To study the antioxidant activity of the ethyl acetate extract of Amomum villosum Lour.[Methods]The removal rate of chelated iron ions,hydroxyl radicals,superoxide anion free radicals and DPPH free radicals by the ethyl acetate extract of A.villosum Lour.was determined by UV spectrophotometer.[Results]0.5000μg/mL ethyl acetate extract of A.villosum Lour.had the strongest ability to chelate with ferrous ions and to remove hydroxyl radicals,superoxide anion free radicals and DPPH free radicals.The ability to chelate with ferrous ions was 95.14%,and the removal rate of the above free radicals was 86.217%,81.44%,and 85.16%.[Conclusions]The ethyl acetate extract of A.villosum Lour.had a strong antioxidant effect,and its antioxidant capacity was related to the sample concentration,which provides a theoretical basis for its application in the development of antioxidant skin care products. 展开更多
关键词 Amomum villosum Lour. EXTRACT Antioxidant activity Free radicals
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Antioxidant Activity and Phytochemical Screening in Acacia rigidula Benth. Leaves
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作者 Aneth Ochoa-Negrete Rene Rangel +1 位作者 Marcus Antonius Ynalvez Ruby A. Ynalvez 《Advances in Bioscience and Biotechnology》 CAS 2024年第1期15-38,共24页
This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoli... This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin. 展开更多
关键词 ACACIA Plant Extract Antioxidant activity Total Phenolic Acid HPLC Gallic Acid
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UV,five wavelengths fusion and electrochemical fingerprints combined with antioxidant activity for quality control of antiviral mixture
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作者 Kaining Zhou Zini Tang +2 位作者 Guoxiang Sun Ping Guo Lili Lan 《Asian Journal of Traditional Medicines》 2024年第3期119-136,151,共19页
Aiming to ensure the consistency of quality control of Traditional Chinese Medicines(TCMs),a combination method of high-performance liquid chromatography(HPLC),ultraviolet(UV),electrochemical(EC)was developed in this ... Aiming to ensure the consistency of quality control of Traditional Chinese Medicines(TCMs),a combination method of high-performance liquid chromatography(HPLC),ultraviolet(UV),electrochemical(EC)was developed in this study to comprehensively evaluate the quality of Antiviral Mixture(AM),and Comprehensive Linear Quantification Fingerprint Method(CLQFM)was used to process the data.Quantitative analysis of three active substances in TCM was conducted.A fivewavelength fusion fingerprint(FWFF)was developed,using second-order derivatives of UV spectral data to differentiate sample levels effectively.The combination of HPLC and UV spectrophotometry,along with electrochemical fingerprinting(ECFP),successfully evaluated total active substances.Ultimately,a multidimensional profiling analytical system for TCM was developed. 展开更多
关键词 TCM antiviral mixture five-wavelength fusion fingerprint(FWFF) Comprehensive Linear Quantification Fingerprint Method(CLQFM) quantization fingerprint antioxidant activity profilling
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Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization
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作者 L.Antony Catherine Flora Kirubanandan Shanmugam Renganathan Sahadevan 《Proceedings of Anticancer Research》 2024年第5期89-104,共16页
Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the caroten... Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments. 展开更多
关键词 Marine algae FUCOXANTHIN ULTRASONICS Extraction OPTIMIZATION TLC DPPH Antimicrobial antioxidant activities
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Structural and antioxidative properties of royal jelly protein by partial enzymatic hydrolysis 被引量:2
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作者 Shanshan Li Lingchen Tao +3 位作者 Shiqin Peng Xinyu Yu Xiaobin Ma Fuliang Hu 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1820-1827,共8页
The objective of this study was to investigate the structural and antioxidative properties of royal jelly protein(RJP)at different degrees of hydrolysis(DH)by partial enzymatic hydrolysis. RJP was hydrolyzed by alcala... The objective of this study was to investigate the structural and antioxidative properties of royal jelly protein(RJP)at different degrees of hydrolysis(DH)by partial enzymatic hydrolysis. RJP was hydrolyzed by alcalase for 0 min, 15 min, 1 h, 5 h and 8 h to obtain hydrolysates at DH of 5.34%, 11.65%, 15.19%, 21.38% and 23.91%, respectively. With the increased DH, the RJP hydrolysates showed elevated antioxidative activities. The molecular weight of RJP hydrolysates was significantly decreased but their primary backbone kept unchanged. Analysis of circular dichroism spectra revealed that the enzymolysis reduced the content of α-helix but increased the contents of β-sheet, β-turn and random coil. Meanwhile, the surface hydrophobicity and fluorescence intensity of RJP hydrolysates were decreased and a red shift occurred. As the enzymolysis continued, the surface morphology of RJP was gradually changed from a sheet-like structure into microparticles. Changes in antioxidative activities and structures generally followed a DH-dependent manner, however these changes became insignificant for samples at DH beyond 20%. Taking into consideration of both effectiveness and productivity, the optimum enzymatic duration was determined at 5 h. 展开更多
关键词 Royal jelly protein Acalase Enzymatic hydrolysis antioxidative activity STRUCTURE
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Effect of Ultrasound and Thermal Pasteurization on Physicochemical Properties and Antioxidant Activity of Juice Extracted from Ripe and Overripe Pineapple 被引量:2
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作者 Asraful Alam Mrityunjoy Biswas +5 位作者 Tanjim Ahmed Md. Ashrafuzzaman Zahid Mahfujul Alam Mustafa Kamrul Hasan Bikramjit Biswas Roxana Zaman 《Food and Nutrition Sciences》 CAS 2023年第4期300-314,共15页
It has become necessary to assess how food processing methods affect qualitative qualities due to the increased consumer awareness of the health benefits of various nutrients in food. In the current study, the effects... It has become necessary to assess how food processing methods affect qualitative qualities due to the increased consumer awareness of the health benefits of various nutrients in food. In the current study, the effects of ultrasound treatment (37°C, 5 min), pasteurization (90°C, 5 min), and their combination on quality parameters, including pH, total soluble solids (TSSs), titratable acidity (TA), color values (L*, a*, b*), ascorbic acid (AA), total phenolic content (TPC), and antioxidant activity (DPPH), of pineapple juice from ripe and overripe pineapples were assessed. Color values (L*), ascorbic acid (AA), total phenolic content (TPC), and DPPH radical scavenging activity in all juice samples that were sonicated alone and in combination with pasteurization improved significantly (p and color value (a* and b*) decreased in comparison to the control. Whereas pH and acidity did not change significantly (p < 0.05). Pasteurization significantly (p , but sonicated samples significantly (p quality parameters and antioxidant activity, notably in ripe juice. Overall, pasteurization degraded these liquids but sonication, either alone or in combination with it, was advantageous for preserving their quality by retaining nutrients. 展开更多
关键词 Pineapple Juice ULTRASOUND PASTEURIZATION Phenolic Compounds Antioxidant activity
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Functional properties,antioxidant activity and in-vitro digestibility characteristics of brown and polished rice flours of Indian temperate region 被引量:1
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作者 Nafiya Qadir Idrees Ahmed Wani 《Grain & Oil Science and Technology》 2023年第1期43-57,共15页
The present investigation was aimed to study functional properties,antioxidant activity and in-vitro digestibility characteristics of brown and polished flours obtained from four rice cultivars(SR-4,K-39,Mushq Budij a... The present investigation was aimed to study functional properties,antioxidant activity and in-vitro digestibility characteristics of brown and polished flours obtained from four rice cultivars(SR-4,K-39,Mushq Budij and Zhag)of Kashmir.Brown rice flours had higher total dietary fibre(3.08%-3.68%),oil absorption(116.0%-139.0%),emulsion capacity(4.78%-9.52%),emulsion stability(87.46%-99.93%)and resistant starch content(6.80%-9.00%)than polished flours.However,polished flours presented greater water absorption(102.0%-122.0%),foaming capacity(8.00%-13.63%),apparent amylose(19.16%-22.62%),peak(2260.0-2408.0 cP),trough(1372.0-1589.0 cP)and breakdown(714.0-978.0 cP)viscosities than their brown counterparts.Brown rice flours depicted highest total phenolic content(4.40-6.40 mg GAE/g)and inhibition of lipid peroxidation(19.50%-33.20%).However,equilibrium starch hydrolysis percentage(C∞)and predicted glycemic index of brown rice flours were lower than their polished counterparts.Among rice cultivars,brown Zhag flour had the highest total dietary fibre(3.68%),emulsion capacity(9.52%),emulsion stability(99.93%),resistant starch(9.00%),DPPH radical scavenging activity(85.45%)and inhibition of lipid peroxidation(33.20%),respectively.Emulsion capacity and emulsion stability were positively correlated with protein content of rice flours.However,peak,trough,breakdown and setback viscosities were negatively correlated with protein and fat contents of rice flour.The present investigation will be helpful in identifying nutritive role of rice flours from studied cultivars in human diet. 展开更多
关键词 POLISHING Rice flour Functional properties Antioxidant activity In-vitro digestibility
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Composition and antioxidant activity of Paeonia lactiflora petal flavonoid extract and underlying mechanisms of the protective effect on H_(2)O_(2)-induced oxidative damage in BRL3A cells
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作者 Lei Liu Yingdan Yuan +1 位作者 Jiajia Zuo Jun Tao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期335-344,共10页
Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UH... Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UHPLC-ESI-Q-Exactive HF MS/MS method was established for characterization, and 21 predominant flavonoid compounds were tentatively identified in PPF. Among them, isoscutellarein-7-(6’-acetylallosyl-(1->2)-glucoside) and scutellarin methylester were discovered in PPF for the first time. Pretreatment with PPF significantly reduced H2O2-induced cell damage, ROS accumulation, and malondialdehyde content and increased the activity of SOD, CAT, and GSH-Px in buffalo rat liver 3A(BRL3A) cells. Moreover, the expression of nuclear Factor E2-related factor(Nrf2) was upregulated by PPF, whose expression trend was consistent with that of heme oxygenase-1(HO-1), glutamate-cysteine ligase catalytic subunit(GCLC), and NAD(P)H quinone oxidoreductase-1(NQO1). These findings suggested that herbaceous peony flavonoids can be used as a natural bioactive agent to prevent oxidative stress. 展开更多
关键词 Antioxidant activity Flavonoid Herbaceous peony petal Oxidative stress Solid-phase extraction
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Synthesis and Antioxidant Activity of(E)ω-Formylcamphene-Based Thiazole Hydrazone Derivatives
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作者 Jiayu Chang Qingying Ding +9 位作者 Chong Zhong Yao Long Zhuanquan Xiao Hai Luo Yuling Yang Zongde Wang Shengliang Liao Jinzhu Chen Shangxing Chen Ji Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第1期379-391,共13页
(E)ω-formylcamphene was synthesized fromα-pinene,the main component of turpentine,and then reacted with thiosemicarbazide to obtain(E)ω-formylcamphene thiosemicarbazide 3,which was reacted with 14α-bromoace-tophen... (E)ω-formylcamphene was synthesized fromα-pinene,the main component of turpentine,and then reacted with thiosemicarbazide to obtain(E)ω-formylcamphene thiosemicarbazide 3,which was reacted with 14α-bromoace-tophenone compounds to obtain 14(E)ω-formylcamphene thiazole hydrazone compounds 5a–5n;the yields were all above 80%.The structures of the target compounds were characterized by IR,^(1)H-NMR,^(13)C-NMR,and HR-MS analyses.Then,500,250,125,62.5,and 31.25 mg/L drug solutions were prepared.Free radical scavenging experi-ments of 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2-bis(3-ethyl-benzothiazole-6-sulfonic acid)diammonium salt(ABTS)were carried out with Trolox and L-ascorbic acid as the control samples.The scavenging rates of 14 compounds for DPPH and ABTS free radicals were obtained;the IC_(50) values of scavenging free radicals were fitted using SPSS software.The results show that 14(E)ω-formylcamphene-based thiazole hydrazone compounds exhibited good scavenging effects on the two free radicals,especially when the concentration of the drug solution was 125 and 62.5 mg/L;most compounds exceeded the scavenging efficiency of Trolox and L-ascorbic acid. 展开更多
关键词 (E)ω-formylcamphene THIOSEMICARBAZONE thiazohydrazone structural analysis antioxidant activity
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Bioactivity profile of dissolved organic matter and its relation to molecular composition
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作者 Teresa S.Catalá Linn G.Speidel +2 位作者 Arlette Wenzel-Storjohann Thorsten Dittmar Deniz Tasdemir 《Natural Products and Bioprospecting》 CSCD 2023年第1期425-440,共16页
Dissolved organic matter(DOM)occupies a huge and uncharted molecular space.Given its properties,DOM can be presented as a promising biotechnological resource.However,research into bioactivities of DOM is still in earl... Dissolved organic matter(DOM)occupies a huge and uncharted molecular space.Given its properties,DOM can be presented as a promising biotechnological resource.However,research into bioactivities of DOM is still in early stages.In this study,the biotechnological potential of terrestrial and marine DOM,its molecular composition and their relationships are investigated.Samples were screened for their in vitro antibacterial,antifungal,anticancer and antioxidant activities.Antibacterial activity was detected against Staphylococcus aureus in almost all DOM samples,with freshwater DOM showing the lowest IC50 values.Most samples also inhibited Staphylococcus epidermidis,and four DOM extracts showed up to fourfold higher potency than the reference drug.Antifungal activity was limited to only porewater DOM towards human dermatophyte Trichophyton rubrum.No significant in vitro anticancer activity was observed.Low antioxidant potential was exerted.The molecular characterization by FT-ICR MS allowed a broad compositional overview.Three main distinguished groups have been identified by PCoA analyses.Antibacterial activities are related to high aromaticity content and highly-unsaturated molecular formulae(O-poor).Antifungal effect is correlated with highly-unsaturated molecular formulae(O-rich).Antioxidant activity is positively related to the presence of double bonds and polyphenols.This study evidenced for the first time antibacterial and antifungal activity in DOM with potential applications in cosmeceutical,pharmaceutical and aquaculture industry.The lack of cytotoxicity and the almost unlimited presence of this organic material may open new avenues in future marine bioprospect-ing efforts. 展开更多
关键词 Dissolved organic matter Antibacterial activity Antifungal activity Antioxidant activity Molecular composition
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Cd and Hg Mediated Oxidative Stress,Antioxidative Metabolism and Molecular Changes in Soybean(Glycine max L.)
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作者 Sheeba Naaz Nadeem Ahmad +3 位作者 Asma AAl-Huqail Mohammad Irfan Faheema Khan Mohammad Irfan Qureshi 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第6期1725-1742,共18页
Cadmium(Cd)and Mercury(Hg)is among the heavy metals most hazardous for plant and human health.Known to induce oxidative stress in plants and disbalance equilibrium in the antioxidant defence system,these metals alter ... Cadmium(Cd)and Mercury(Hg)is among the heavy metals most hazardous for plant and human health.Known to induce oxidative stress in plants and disbalance equilibrium in the antioxidant defence system,these metals alter plant growth and cause damage at the cellular and molecular levels.Soybean is an important oilseed crop that is raised in soils often contaminated by Cd and Hg.The comparative studies on the deleterious effect of Cd and Hg and the defence system of antioxidants were not studied earlier in soybean plant.In this study,soybean plants were exposed to Cd(100μM CdCl_(2))and Hg(100μM HgCl_(2))and studied for physiological,biochemical and molecular responses.Both Cd and Hg treatment increased the magnitude of oxidative stress.Activities of antioxidant enzymes were significantly upregulated in response to Cd and Hg stress.Quantitative and qualitative assessment of isolated RNA showed significant differences in RNA under stress.Integrity values of RNA confirmed alterations.Transcript level of the Actin gene,involved in the morphogenesis of plants and also used as referenced gene in expression studies was analyzed using qRT-PCR just to check its stability and response under heavy metal stress.Results showed significant upregulation of the gene in the presence of Cd.It can be concluded that both Cd and Hg caused oxidative damage to plants,and adversely affected the quality of RNA.However,soybean tried to limit the adverse impacts of Cd and Hg stress by elevating the antioxidant system and upregulating Actin gene. 展开更多
关键词 SOYBEAN heavy metal stress actin gene enzymatic antioxidant activity QRT-PCR
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Thymoquinone enhances the antioxidant and anticancer activity of Lebanese propolis
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作者 Sima AlDreini Zaynab Fatfat +3 位作者 Najwa Abou Ibrahim Maamoun Fatfat Hala Gali-Muhtasib Hala Khalife 《World Journal of Clinical Oncology》 CAS 2023年第5期203-214,共12页
BACKGROUND Reactive oxygen species(ROS)are produced by multiple cellular processes and are maintained at optimal levels in normal cells by endogenous antioxidants.In recent years,the search for potential exogenous ant... BACKGROUND Reactive oxygen species(ROS)are produced by multiple cellular processes and are maintained at optimal levels in normal cells by endogenous antioxidants.In recent years,the search for potential exogenous antioxidants from dietary sources has gained considerable attention to eliminate excess ROS that is associated with oxidative stress related diseases including cancer.Propolis,a resinous honeybee product,has been shown to have protective effects against oxidative stress and anticancer effects against several types of neoplasms.AIM To investigate the antioxidant and anticancer potential of Lebanese propolis when applied alone or in combination with the promising anticancer compound Thymoquinone(TQ)the main constituent of Nigella sativa essential oil.METHODS Crude extracts of Lebanese propolis collected from two locations,Rashaya and Akkar-Danniyeh,were prepared in methanol and the total phenolic content was determined by Folin–Ciocalteu method.The antioxidant activity was assessed by the ability to scavenge 2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical and to inhibit H2O2-induced oxidative hemolysis of human erythrocytes.The anticancer activity was evaluated by[3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide]MTT assay against HCT-116 human colorectal cancer cells and MDAMB-231 human breast cancer cells.RESULTS The total phenolic content of propolis extract from Rashaya and Akkar-Danniyeh were 56.81μg and 83.503μg of gallic acid equivalent/mg of propolis,respectively.Both natural agents exhibited strong antioxidant activities as evidenced by their ability to scavenge DPPH free radical and to protect erythrocytes against H2O2-induced hemolysis.They also dose-dependently decreased the viability of both cancer cell lines.The IC50 value of each of propolis extract from Rashaya and Akkar-Danniyeh or TQ was 22.3,61.7,40.44μg/mL for breast cancer cells at 72 h and 33.3,50.9,33.5μg/mL for colorectal cancer cells at the same time point,respectively.Importantly,the inhibitory effects of propolis on DPPH radicals and cancer cell viability were achieved at half its concentration when combined with TQ.CONCLUSION Our results indicate that Lebanese propolis extract has antioxidant and anticancer potential and its combination with TQ could possibly prevent ROS-mediated diseases. 展开更多
关键词 Lebanese propolis THYMOQUINONE COMBINATION Antioxidant activity Anticancer activity Phenolic compounds
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Extraction,Antioxidant Activity and Identification of Flavonoids from Root Tubers of Kosteletzkya virginica
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作者 Yu Zai Shaohua Liu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期225-236,共12页
Kosteletzkya virginica(K.virginica)is used for revegetation of salt-affected coastal tidal flats and as a raw material of biodiesel.K.virginica root tuber,a biowaste with low economic value,is rich in bioactive compou... Kosteletzkya virginica(K.virginica)is used for revegetation of salt-affected coastal tidal flats and as a raw material of biodiesel.K.virginica root tuber,a biowaste with low economic value,is rich in bioactive compounds.This study aimed to extract and identify flavonoids from K.virginica root tubers.The optimal extraction conditions were 1/25(w/v)solid/liquid ratio,40%ethanol concentration at 40℃ for 60 min.Under these conditions,65.2±3.7 mg/g total flavonoid content was extracted from the roots,which were collected from salinized soil in late autumn of the third year.Antioxidant activity was evaluated through 1,1-diphenyl-2-picrylhydrazyl,hydroxyl radical,and superoxide anion scavenging assays.The extracted flavonoids exhibited antioxidant activity in a dose-dependent manner.Five flavonoids,glucoliquiritin apioside,licoisoflavone B,5-methoxy-7,8-diprenylflavone,7,2′-dihydroxy-6,8-dimethyl-4′,5′-methylenedioxyflavan,and 5,7,4′-trihydroxy-3′-methoxy-6,8-di-Cmethylflavanone,were identified by ultra-performance liquid chromatography–tandem mass spectrometry.Our results suggest that the flavonoids of K.virginica root tubers might be potent antioxidants and can be effectively applied as an ingredient in food and natural medicine. 展开更多
关键词 Kosteletzkya virginica total flavonoid antioxidant activity UPLC-MS/MS
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