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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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V(HSO_4)_3 catalyzed chemoselectivity acetylation of alcohols and phenols in solution and under solvent-free conditions 被引量:2
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作者 Farhad Shirini Ali Reza Sakhaei Masoumeh Abedini 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期439-443,共5页
A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yiel... A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yields of the products, easy procedure and selective acetylation of alcohols and phenols in the presence of amines and thiols are the main advantages of this procedure. 展开更多
关键词 ALCOHOLS phenolS ACETYLATION Solvent-free conditions Vanadium hydrogen sulfate
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Glycerol-Based Carbon-SO<sub>3</sub>H Catalyzed Benign Synthetic Protocol for the Acetylation of Alcohols, Phenols and Amines under Solvent-Free Conditions
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作者 Katakam N. Gangadhar Manneganti Vijay +1 位作者 Rachapudi Badari Narayana Prasad Bhetala Lakshmi Anu Prabhavathi Devi 《Green and Sustainable Chemistry》 2013年第2期122-128,共7页
A simple and efficient solvent-free method was developed for the acetylation of alcohols, phenols and amines in excellent yields employing glycerol-based sulfonic acid (-SO3H) functionalized carbon catalyst under envi... A simple and efficient solvent-free method was developed for the acetylation of alcohols, phenols and amines in excellent yields employing glycerol-based sulfonic acid (-SO3H) functionalized carbon catalyst under environmentally benign reaction conditions. The salient features of this protocol are the short reaction time, ease of product isolation and reusability of the carbon catalyst. 展开更多
关键词 ACETYLATION Glycerol-Based Carbon-SO3H Catalyst Solvent-free Method ALCOHOLS phenolS AMINES
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在红枣汁中乳酸菌、酵母菌单一及偶联发酵特征物质差异分析
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作者 张江宁 叶峥 杨春 《现代食品科技》 CAS 北大核心 2024年第5期64-72,共9页
该试验以红枣为原料,研究乳酸菌、酵母菌单一及偶联发酵对枣汁总糖、总酸、总酚、黄酮和酒精含量的影响,使用液相色谱-质谱联用(Liquid Chromatograph-Mass Spectrometer,LC-MS)技术进行游离型酚酸差异分析,气相色谱-离子迁移谱联用(Gas... 该试验以红枣为原料,研究乳酸菌、酵母菌单一及偶联发酵对枣汁总糖、总酸、总酚、黄酮和酒精含量的影响,使用液相色谱-质谱联用(Liquid Chromatograph-Mass Spectrometer,LC-MS)技术进行游离型酚酸差异分析,气相色谱-离子迁移谱联用(Gas Chromatography-Ion Migration Spectrum,GC-IMS)技术进行挥发性有机物差异分析。结果表明,原枣汁无论是单一菌种发酵还是混合菌种发酵,总糖、黄酮含量降低,总酸、总酚含量、酒精度均增加,反式阿魏酸、4-羟基苯甲酸、氢化肉桂酸、香草酸、苯甲酸、丁香酸增加;酵母菌发酵枣汁总酚、黄酮、酒精度、苯丙氨酸、儿茶素、表儿茶素、丁香酸、芥子酸含量均高于乳酸菌发酵枣汁,总酸含量低于乳酸菌发酵枣汁;经混菌偶联发酵,糖类物质降解效率、产酸效率、总酚生成率、黄酮留存率以及产酒精效率更高;游离型酚酸反式阿魏酸、反式肉桂酸、香草酸、没食子酸、对香豆酸、苯甲酸、原儿茶酸、咖啡酸、丁香酸较单菌发酵样品高;挥发性成分53种,包括11种醇类化合物、9种酯类化合物、8种酮类化合物、8种醛类化合物、2种酸类化合物、2种吡嗪吡嗪类化合物,混菌发酵样品中风味物质酯类、醇类、醛类分别占17.2%、58.2%、和1.3%,酯类和醛类显著高于乳酸菌发酵样品、酵母菌发酵样品及原枣汁,香味浓烈,因此采用酵母菌、乳酸菌混合发酵,可以有效地增强发酵枣汁的品质,丰富口感,该研究为推动混菌发酵在红枣酵素发酵生产行业的应用,提供相应的理论基础和科学实践依据。 展开更多
关键词 红枣 混菌发酵 游离型酚酸 风味物质
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桑葚果实、桑葚干酒和桑葚利口酒中酚类化合物的高效液相色谱串联电喷雾二级质谱分析及其抗氧化活性比较
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作者 张文娜 魏萌 +7 位作者 韩爱云 陈佳 胡连霞 解立斌 李亚楠 白佳敏 剧慧栋 陈永民 《食品与发酵工业》 CAS CSCD 北大核心 2024年第14期246-252,共7页
为了解桑葚果酒和桑葚果实在酚类化合物的种类、含量及抗氧化活性之间的差异,该研究以桑葚果实、桑葚干酒和桑葚利口酒为试材,采用高效液相色谱串联电喷雾二级质谱(high performance liquid chromatography-electron spray ionization-m... 为了解桑葚果酒和桑葚果实在酚类化合物的种类、含量及抗氧化活性之间的差异,该研究以桑葚果实、桑葚干酒和桑葚利口酒为试材,采用高效液相色谱串联电喷雾二级质谱(high performance liquid chromatography-electron spray ionization-mass spectrometry/mass spectrometry,HPLC-ESI-MS/MS)对酚类化合物进行定性定量分析。HPLC-ESI-MS/MS分析结果表明,在桑葚果实、桑葚干酒和桑葚利口酒中均检测到花青素-3-葡萄糖苷和花青素-3-芸香糖苷,而花葵素-3-芸香糖苷和4-丙酮酸-花青素-3-葡萄糖苷分别只在桑葚干酒和桑葚利口酒中被检测到。同时,桑葚干酒和桑葚利口酒中花青素-3-葡萄糖苷和花青素-3-芸香糖苷的含量均显著低于桑葚果实。此外,在桑葚果实中鉴定的8种非花色苷多酚中,仅有4种存在于桑葚干酒和桑葚利口酒中。相较于桑葚果实,桑葚干酒和利口酒中原儿茶素、二氢槲皮素和槲皮素的含量显著升高。桑葚果实DPPH自由基清除能力介于桑葚干酒和利口酒之间。综上,桑葚果酒和桑葚果实中酚类化合物的种类、含量及抗氧化活性之间差异显著。 展开更多
关键词 桑葚果实 桑葚果酒 酚类化合物 DPPH自由基清除能力
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3种云南酿酒葡萄皮渣的营养、化学成分及功能活性 被引量:1
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作者 李雅静 宋静 +5 位作者 陈万谨 田辉 张雪春 王娟 王振兴 武霄 《食品科学》 EI CAS CSCD 北大核心 2024年第12期194-204,共11页
实验以云南酿酒葡萄皮渣(‘玫瑰蜜’‘云中舞’‘法国野’)为原料,测定其营养成分、氨基酸和花青素相关化合物组成。进一步提取3种葡萄皮渣中的游离酚、结合酚和酯化酚,并以1,1-二苯基-2-三硝基苯肼自由基和2,2’-联氮双(3-乙基苯并噻唑... 实验以云南酿酒葡萄皮渣(‘玫瑰蜜’‘云中舞’‘法国野’)为原料,测定其营养成分、氨基酸和花青素相关化合物组成。进一步提取3种葡萄皮渣中的游离酚、结合酚和酯化酚,并以1,1-二苯基-2-三硝基苯肼自由基和2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力、铁还原能力以及α-葡萄糖苷酶和α-淀粉酶抑制能力为指标,评估其体外抗氧化和降血糖活性。同时利用高效液相色谱法对其中的酚类化合物进行定量分析。结果表明,3种葡萄皮渣具有相似的营养组成,具有高膳食纤维、低脂肪的特点,且必需氨基酸含量丰富、组成合理。总体上看,‘玫瑰蜜’具有最高的营养价值。在3种葡萄皮渣中,共检测到2种花青素和34种花色苷,且花色苷主要以-3-O-葡萄糖苷的形式存在,其中‘云中舞’的花青素类化合物含量最高、种类最多,其次为‘玫瑰蜜’;在3种葡萄皮渣中,‘玫瑰蜜’的总酚含量、体外抗氧化能力和α-葡萄糖苷酶抑制能力最强,α-淀粉酶抑制能力与‘法国野’相当。对于不同形式的多酚而言,结合酚的总酚含量和体外抗氧化能力高于游离酚和酯化酚,而酯化酚的α-淀粉酶抑制能力较好。从3种葡萄皮渣中一共检测到18种酚类化合物,其中16种在‘玫瑰蜜’中检测到,并且结合酚中的酚类化合物含量高于游离酚和酯化酚。综上所述,3种葡萄皮渣具有良好的营养价值和功能活性,适合作为高纤维、低脂肪、具有一定抗氧化和降血糖能力的功能食品原料进行开发。其中,‘玫瑰蜜’具有最大的开发价值。研究结果对云南酿酒葡萄皮渣的高值化综合利用具有重要的参考价值,并对云南高原葡萄酒产业的发展具有一定意义。 展开更多
关键词 葡萄皮渣 游离酚 酯化酚 结合酚 营养成分 功能活性
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核桃仁发育过程中不同形态酚及其抗氧化活性的动态变化
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作者 崔茂凯 王若辉 +2 位作者 李庆杨 沈丹玉 刘毅华 《中国粮油学报》 CAS CSCD 北大核心 2024年第2期131-139,共9页
阐明发育期核桃仁中3种不同形态酚(游离、酯化和结合)及其单体酚组成的变化,探究酚类成分与抗氧化能力的关系,为深入了解核桃功能性成分形成规律和深化功能性产品开发提供参考。以核桃品种‘寒丰’为对象,运用UPLC-MS/MS测定3种形态酚组... 阐明发育期核桃仁中3种不同形态酚(游离、酯化和结合)及其单体酚组成的变化,探究酚类成分与抗氧化能力的关系,为深入了解核桃功能性成分形成规律和深化功能性产品开发提供参考。以核桃品种‘寒丰’为对象,运用UPLC-MS/MS测定3种形态酚组成,分光光度计法测定核桃的羟自由基清除能力,皮尔逊相关分析用于研究酚类物质与羟自由基清除能力的相关性关系。在核桃仁发育过程中,酚形态中以游离态为主且占比大于58%;3种形态总酚含量最高值均出现在采前63 d,分别为10.47 mg/g(游离态)、2.76 mg/g(酯化态)、1.28 mg/g(结合态);鞣花酸、咖啡酸、绿原酸等单体酚的3种形态质量分数随着核桃仁发育显著降低(58.03%~88.83%);单体酚含量与抗氧化活性呈现显著相关性,相关系数为0.63~0.97。核桃仁3种形态总酚含量和抗氧化活性最大值均出现在未成熟早期,游离态是核桃仁中提供抗氧化活性的酚类物质主要形态,并且核桃仁发育过程中单体酚的抗氧化能力与成熟度、酚形态有关。 展开更多
关键词 核桃仁 游离酚 结合酚 抗氧化活性 成熟度
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不同发酵时间对沙米甜醅营养、感官品质及其酚类物质抗氧化活性的影响
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作者 黄玉敏 韩富娟 韩立宏 《中国粮油学报》 CAS CSCD 北大核心 2024年第1期75-82,共8页
为促进沙米作为食品原料的开发利用,以其为材料进行甜醅制作,探究不同发酵时间对沙米甜醅营养、食用品质及其酚类物质抗氧化活性的影响。结果表明,不超过12 h的短时发酵处理对沙米成分没有显著性(P>0.05)影响;处理时间大于12 h后,沙... 为促进沙米作为食品原料的开发利用,以其为材料进行甜醅制作,探究不同发酵时间对沙米甜醅营养、食用品质及其酚类物质抗氧化活性的影响。结果表明,不超过12 h的短时发酵处理对沙米成分没有显著性(P>0.05)影响;处理时间大于12 h后,沙米甜醅的总酸、还原糖含量随处理时间延长显著增大(P<0.05),两者均在48 h后出现下降趋势,而游离氨基酸、总酚含量及其DPPH清除率一直呈现显著(P<0.05)升高趋势;36 h及以上的发酵处理可使沙米淀粉中抗性淀粉含量相比对照显著(P<0.05)增大,快速消化淀粉显著(P<0.05)降低;发酵处理使得沙米色泽偏红偏黄,饱和度增高;感官评价表明发酵48 h的沙米甜醅食用品质最佳。 展开更多
关键词 沙米甜醅 发酵时间 游离氨基酸 酚类物质 抗氧化 消化特性
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黑涩石楠总多酚超声辅助提取工艺优化、抗氧化活性评价及单体酚分析
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作者 罗维巍 吕琳琳 +3 位作者 孙丽阳 李铁纯 郭俊生 刁全平 《中国酿造》 CAS 北大核心 2024年第5期199-205,共7页
以黑涩石楠冻果为原料,采用单因素试验结合响应面法优化超声波辅助提取黑涩石楠果实中总多酚工艺,并对其体外抗氧化活性及单体酚分进行分析。结果表明,黑涩石楠总多酚的最佳提取工艺条件为:乙醇体积分数54%、超声提取时间125 min、超声... 以黑涩石楠冻果为原料,采用单因素试验结合响应面法优化超声波辅助提取黑涩石楠果实中总多酚工艺,并对其体外抗氧化活性及单体酚分进行分析。结果表明,黑涩石楠总多酚的最佳提取工艺条件为:乙醇体积分数54%、超声提取时间125 min、超声提取温度46℃、料液比1∶40(g∶mL)、超声提取功率700 W,超声提取频率40 kHz。在此优化条件下,总多酚的提取量为(12.69±0.079)mg/g。黑涩石楠总多酚具有较强的抗氧化能力,其对1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、2,2'-联氨-双(3-乙基苯并噻唑啉-6-磺酸)二胺盐自由基(ABTS^(+)·)和超氧阴离子自由基(O_(2)^(-)·)的半抑制浓度(IC_(50))值分别为0.30 mg/mL、0.42 mg/mL和0.35 mg/mL。经高效液相色谱(HPLC)分析,黑涩石楠中含有原儿茶酸、新绿原酸、绿原酸、咖啡酸和槲皮素等单体酚,含量分别为0.24 mg/g、1.08 mg/g、2.22 mg/g、0.31 mg/g和0.31 mg/g。 展开更多
关键词 黑涩石楠 多酚 超声波辅助提取 响应面法 抗氧化活性 单体酚
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Free radical scavenging and reducing power of Lawsonia inermis L.seeds 被引量:1
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作者 Philip Jacob P Madhumitha G Mary Saral A 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第6期457-461,共5页
Objective:To determine the antioxidant activity,total phenolic and flavonoid content of Petroleum ether extract(PE),Dichloromethane extract(DCM),Ethanol extract(ET) and aqueous extract(AQ) of henna seeds.Metho... Objective:To determine the antioxidant activity,total phenolic and flavonoid content of Petroleum ether extract(PE),Dichloromethane extract(DCM),Ethanol extract(ET) and aqueous extract(AQ) of henna seeds.Methods:Total antioxidant assay(phosphomolybenum method), DPPH radical scavenging assay,reducing power assay and lipid peroxidation inhibition assay were used to ascertain the potential of seeds as an antioxidant.Results:In all the assays carried out ET showed a greater potential to scavenge DPPH radical,reduce MO(Ⅳ) to MO(Ⅴ) complex and Fe(Ⅲ) to Fe(Ⅱ) and to inhibit lipid peroxidation.The IC<sub>50</sub> of ET was far greater than that of the standard,ascorbic acid(AS) in the lipid peroxidation assay.The activity of AQ was lesser when compared with that of ET but greater than PE and DCM.The amount of phenolics and flavonoids were present in higher amounts in ET followed by AQ.Trace amounts of phenolics were detected in PE and DCM,but the amount of flavonoids were below the detection level.The study showed that the antioxidant activity and the concentrations of phenolics and flavonoids are proportionate to each other.Conclusions:Ethanolic extract of henna seeds are efficient antioxidants,which can be utilized for further isolation of active compounds and pharmaceutical applications. 展开更多
关键词 Lawsonia inermis ANTIOXIDANT REDUCING free RADICAL phenolics FLAVONOIDS
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Silica triflate as an efficient reagent for the solvent-free synthesis of coumarins 被引量:1
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作者 Farhad Shirini Katayoun Marjani +1 位作者 Hossein Taherpour Nahzomi Mohammad Ali Zolfigol 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期909-911,共3页
Silica triflate, as a new silica-based reagent, can be used for the efficient synthesis of 4-substituted coumarins via a Pechmann reaction under solvent-free reaction conditions. All reactions were performed at 80 ℃ ... Silica triflate, as a new silica-based reagent, can be used for the efficient synthesis of 4-substituted coumarins via a Pechmann reaction under solvent-free reaction conditions. All reactions were performed at 80 ℃ in good to high yields. 展开更多
关键词 Silica triflate COUMARINS Pechmann reaction Solvent-free reaction conditions phenolS
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In vitro evaluation of anti-acetylcholinesterase and free radical scavenging potential of leaf extracts of some selected medicinal plants 被引量:1
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作者 Annie Jessica Toppo Sheela Chandra +1 位作者 Dhruv Jha Papiya Mitra Mazumder 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2019年第2期60-65,共6页
Objective: To evaluate the phytochemical present in various solvent extracts from leaves of Ocimum sanctum(L.), Swertia chirayita(L.), Butea monosperma(Lam.) and Stevia rebaudiana(Bert.) as well as antioxidant and ant... Objective: To evaluate the phytochemical present in various solvent extracts from leaves of Ocimum sanctum(L.), Swertia chirayita(L.), Butea monosperma(Lam.) and Stevia rebaudiana(Bert.) as well as antioxidant and anticholinergic activities employing different in vitro models. Methods: Total phenol content of diethyl ether, chloroform and methanolic extracts obtained from leaves of different medicinal plants was determined by Folin-Ciocalteau's spectrophotometric method. Moreover, antioxidant and anticholinergic studies were conducted by four different in vitro methods which included diphenyl picrylhydrazyl radical scavenging, 2,2-azinobis(3-ethylbezoline-6-sulphonic acid), reducing activity by ferrous reduced antioxidant power and anti-acetylcholinesterase assay, in order to ensure pharmacological potential of the plants. Results: The methanolic leaf extract of Ocimum sanctum showed the highest total phenol content which was(21.13±1.04) GAE/g DW and antioxidant activities compared to other plants with the IC50 value of 40.43 μg/mL in diphenyl picrylhydrazyl radical scavenging assay and 53.5 μg/mL in 2,2-azinobis(3-ethylbezoline-6-sulphonic acid) assay as well as metal ion reduced by(78.22±0.38) TE/g DW in ferrous reduced antioxidant power assay. The inhibition percentage of the anti-acetylcholinesterase assay was(94.22±0.26)%. Conclusions: The results of our current study show that Ocimum sanctum leaf is the most significant source of phytochemicals that possesses antioxidant and anticholinergic properties. However, further investigation on isolation and characterization of active compound which is responsible for the pharmacological potential is needed. 展开更多
关键词 DPPH ASSAY Antioxidant free RADICAL Anti-acetylcholinesterase phenolics content
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代用茶茶汤中功能性成分组成及含量分析 被引量:3
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作者 赵珊 杨飞洋 +5 位作者 秦琳 李曦 黄世群 郑幸果 雷欣宇 仲伶俐 《食品研究与开发》 CAS 北大核心 2023年第2期162-168,共7页
该文选取18种代用茶为研究对象,包括蒲公英、桑叶茶、荷叶、黑苦荞、黄金苦荞、全株苦荞、决明子、红枣片、黑枸杞、红枸杞、山楂片、陈皮、茉莉花、胎菊、金盏菊、玫瑰花、金银花和牛蒡根。以游离氨基酸、总酚、总黄酮、游离酚酸、花... 该文选取18种代用茶为研究对象,包括蒲公英、桑叶茶、荷叶、黑苦荞、黄金苦荞、全株苦荞、决明子、红枣片、黑枸杞、红枸杞、山楂片、陈皮、茉莉花、胎菊、金盏菊、玫瑰花、金银花和牛蒡根。以游离氨基酸、总酚、总黄酮、游离酚酸、花青素、可溶性糖和多糖为成分考察指标,分析其茶汤中功能性成分的组成和含量,比较水提和醇提对代用茶中总酚、总黄酮和花青素浸出的影响。结果表明:18种代用茶中水浸出物含量为13.1%DW~86.6%DW,其中大部分组成是可溶性糖和多糖,占12.1%~98.0%;游离氨基酸和酚酸分别检出18种和14种,含量较高的氨基酸有精氨酸、天冬酰胺、脯氨酸以及绿原酸类酚酸。玫瑰花的总酚(181.1 mg GAE/g DW)和游离氨基酸总量含量(42.8 mg/g DW)最高;荷叶的总黄酮含量(41.0 mg RE/g DW)最高,金盏菊的多糖含量(6.4%DW)最高,金银花和胎菊中绿原酸类成分含量(54.7、53.7 mg/g DW)较高。2种提取方式的结果表明大部分样品茶汤中总酚、总黄酮和花青素的含量占醇提取物的60%以上。 展开更多
关键词 代用茶 茶汤 功能性成分 游离氨基酸 酚酸 黄酮
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Oxalic acid catalyzed solvent-free one pot synthesis of coumarins 被引量:4
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作者 Nagnnath D.Kokare Jaiprkash N.Sangshetti Devanand B.Shinde 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1309-1312,共4页
草酸酸被发现是为 Pechmann 冷凝作用的有效催化剂,它包括在酚和香豆素衍生物的β - keto 酉旨导致形成之间的反应。现在的方法的优点是便宜、容易的可得到的催化剂,没有溶剂的反应条件,更好的收益和更短的反应时间的使用。
关键词 香豆素 草酸 溶剂自由反应 冷凝 苯酚
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园艺绿化用胶粘剂的合成与粘接性能研究 被引量:1
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作者 王瑜 李福全 《粘接》 CAS 2023年第12期38-41,共4页
为了开发出环保型高性能园艺绿化用胶粘剂,考察了各种条件因素对园艺绿化用胶粘剂的游离甲醛、游离苯酚含量和粘接强度的影响。结果表明,当胶粘剂中NaOH用量为4%、木质素取代率为40%、反应温度和时间分别为80℃和1.5 h、甲醛/木质素比例... 为了开发出环保型高性能园艺绿化用胶粘剂,考察了各种条件因素对园艺绿化用胶粘剂的游离甲醛、游离苯酚含量和粘接强度的影响。结果表明,当胶粘剂中NaOH用量为4%、木质素取代率为40%、反应温度和时间分别为80℃和1.5 h、甲醛/木质素比例为10%时,胶粘剂具有较低的游离甲醛、游离苯酚和较高的胶合强度。在此基础上,进一步研究表明,尿素添加有助于提升胶粘剂的胶合强度,且随着尿素添加量升高,胶粘剂的胶合强度先增大后减小,在尿素添加量4%时取得最大值。 展开更多
关键词 胶粘剂 影响因素 游离苯酚 游离甲醛 胶合强度
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An Environment Friendly, Low-Cost Extraction Process of Phenolic Compounds from Grape Byproducts. Optimization by Multi-Response Surface Methodology
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作者 Hiba N. Rajha Nada El Darra +2 位作者 Eugène Vorobiev Nicolas Louka Richard G. Maroun 《Food and Nutrition Sciences》 2013年第6期650-659,共10页
Due to their beneficial effects on human health, phenolic compounds are increasingly attracting the attention of scientists and researchers all over the world. The main interest is in the extraction process of those n... Due to their beneficial effects on human health, phenolic compounds are increasingly attracting the attention of scientists and researchers all over the world. The main interest is in the extraction process of those natural plant-originated compounds from fruits, vegetables and plant wastes, namely grape wastes, in which phenolic compounds are the most abundant secondary metabolites. This waste exploitation not only re-assimilates those byproducts into the food cycle, but also avoids major environmental problems. Herein, the optimization of the phenolic compounds concentration and free radical scavenging activity from Cabernet Sauvignon grape byproducts was conducted, using multi-response surface methodology. A conventional solid-liquid extraction process was performed with pure water as a solvent to study the effects of both time and temperature on the procedure. The maximal phenolic compounds concentration (878.9 mg/L) was reached at 47℃ after 30 hours while the optimal free radical scavenging activity (41.15%) was obtained at 30℃ after 20 hours. A multi-response surface methodology compromised between the quantity and the quality of the extracted phenolics, and the parameters maximizing both responses were obtained at 37℃ and 28 hours. This low-cost and energy saving process provides an excellent tool for further industrial applications. 展开更多
关键词 phenolIC Compounds GRAPE BYPRODUCTS Extraction OPTIMIZATION free RADICAL SCAVENGING Activity
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海带、坛紫菜和裙带菜游离和结合酚抗氧化和酶抑制活性比较 被引量:2
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作者 彭春彦 谢星 +4 位作者 李一华 胡朋朋 谢作桦 涂宗财 张露 《食品与发酵工业》 CAS CSCD 北大核心 2023年第4期110-116,共7页
海带、坛紫菜和裙带菜是我国大型经济海藻,具有丰富的营养价值和保健功能。该文对比研究了海带、坛紫菜和裙带菜中游离和结合酚提取物的总酚含量、总黄酮含量、抗氧化能力,以及α-葡萄糖苷酶、酪氨酸酶和乙酰胆碱酯酶的抑制能力,旨在为... 海带、坛紫菜和裙带菜是我国大型经济海藻,具有丰富的营养价值和保健功能。该文对比研究了海带、坛紫菜和裙带菜中游离和结合酚提取物的总酚含量、总黄酮含量、抗氧化能力,以及α-葡萄糖苷酶、酪氨酸酶和乙酰胆碱酯酶的抑制能力,旨在为3种海藻的高附加值开发提供指导。结果表明,3种海藻原料中均以结合酚为主,坛紫菜结合酚提取物具有最高的总酚含量(干物质内含量)(863.53μg/g)[以没食子酸当量(gallic acid equivalent,GAE)计],其次为裙带菜结合酚提取物(819.67μg GAE/g);裙带菜游离酚提取物中的总黄酮含量最高(干物质内含量)(49.31μg/g)[以槲皮素当量(quercetin equivalent,QE)计]。海带结合酚提取物具有最强的DPPH自由基清除和酪氨酸酶活性抑制能力,裙带菜结合酚提取物的α-葡萄糖苷酶和乙酰胆碱酯酶抑制能力最强,而坛紫菜游离酚提取物的ABTS阳离子自由基清除能力最强,IC 50值分别为401.19、196.28、156.52、289.46、213.21μg/mL,海带和裙带菜结合酚提取物的铁离子还原能力较好,且无显著差异(P>0.05)。相关性分析表明,酚类化合物是3种海藻提取物中主要的抗氧化和酶活性抑制成分。因此,相比于其他两种海藻,海带作为抗氧化剂和酪氨酸酶抑制剂的开发潜力更大,裙带菜可作为α-葡萄糖苷酶和乙酰胆碱酯酶抑制剂的潜在资源。 展开更多
关键词 海藻 结合酚 游离酚 酶抑制活性 抗氧化活性
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高铁酸钾降解隧道施工废水中苯酚的效能研究
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作者 熊鹰 邓钰伟 +3 位作者 刘万林 刘黎东 唐祥辉 刘媛媛 《水处理技术》 CAS CSCD 北大核心 2023年第10期52-56,共5页
采用高铁酸钾对两种隧道施工废水中的苯酚、COD、氨氮(NH3-N)进行去除,并分别研究高铁酸钾浓度、温度、pH、时间和苯酚浓度对苯酚去除效果的影响。采用纳氏比色法、分光光度法、高效液相色谱法对废水中的NH3-N、COD、苯酚浓度进行测定;... 采用高铁酸钾对两种隧道施工废水中的苯酚、COD、氨氮(NH3-N)进行去除,并分别研究高铁酸钾浓度、温度、pH、时间和苯酚浓度对苯酚去除效果的影响。采用纳氏比色法、分光光度法、高效液相色谱法对废水中的NH3-N、COD、苯酚浓度进行测定;通过设计砂柱实验,模拟真实的地下水环境系统下处理苯酚污染的地下水。结果表明:高铁酸钾去除含苯酚的隧道施工废水效果较好;施工废水中的苯酚降解随高铁酸钾的投加量增加而增加、随温度的升高而降低;施工废水中的苯酚降解在酸性条件下效果较好,随着pH的增加效果降低;同时,高铁酸钾对含苯酚的隧道施工废水中的COD、氨氮(NH3-N)去除也有一定效果。通过淬灭实验探究反应当中的产生的自由基类别。 展开更多
关键词 高铁酸钾 苯酚 隧道施工废水 自由基
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Antioxidant Activity of 50 Traditional Chinese Medicinal Materials Varies with Total Phenolics 被引量:1
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作者 Zhengyou He Minbo Lan +2 位作者 Dongying Lu Hongli Zhao Huihui Yuan 《Chinese Medicine》 2013年第4期148-156,共9页
This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent ex... This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage. 展开更多
关键词 TRADITIONAL CHINESE MEDICINAL Material Total phenolics ANTIOXIDANT ACTIVITY Ferric Reducing/Antioxidant Power free Radical SCAVENGING ACTIVITY
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乳杆菌发酵对黑米多酚含量及组成的影响 被引量:2
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作者 刘秉杰 崔春丹 陈中 《食品工业科技》 CAS 北大核心 2023年第5期114-120,共7页
以植物乳杆菌(Lactobacillus plantarum 115,LP)、嗜酸乳杆菌(Lactobacillus acidophilus 14,LA)、干酪乳杆菌(Lactobacillus casei GB,LC)、保加利亚乳杆菌(Lactobacillus bulgaricus 134,LB)、副干酪乳杆菌(Lactobacillus paracasei 3... 以植物乳杆菌(Lactobacillus plantarum 115,LP)、嗜酸乳杆菌(Lactobacillus acidophilus 14,LA)、干酪乳杆菌(Lactobacillus casei GB,LC)、保加利亚乳杆菌(Lactobacillus bulgaricus 134,LB)、副干酪乳杆菌(Lactobacillus paracasei 37,LPC)和鼠李糖乳杆菌(Lactobacillus rhamnosus GG,LGG)为发酵菌种,研究乳杆菌发酵对黑米游离酚和结合酚的含量及组成的影响。结果表明,6株乳杆菌发酵均显著提高了黑米游离酚的含量,但不同乳杆菌发酵后提高的程度具有显著差异,其中提高最显著的是LB。不同乳杆菌发酵后黑米中9种游离态和结合态单体酚的含量变化存在显著差异,其中,6株乳杆菌发酵后黑米中游离态的香草酸和对羟基苯甲酸的含量均显著降低(P<0.05),LP菌株除外游离态咖啡酸的含量均显著提高(P<0.05),而6株乳杆菌发酵后结合态阿魏酸含量均显著降低(P<0.05)。该研究为黑米的高效利用和天然活性产品的开发提供参考。 展开更多
关键词 乳杆菌 黑米 游离酚 结合酚
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