Antioxidative and antibacterial effects of seeds and fruit rind of nutraceutical plants belonging to the Fabaceae family

In the present study, the seeds and fruit rind of six plants of the Fabaceae family were selected to evaluate their potential as antioxidant and antibacterial agents. The dried powders were individually extracted with various organic solvents by the cold percolation method, were evaluated for antibacterial activity and methanol extracts used for antioxidant activities. Total phenol, protein and sugar contents were also measured. Antioxidant activities were measured by DPPH free radical scavenging activity, superoxide anion radical scavenging activity and reducing capacity assessment. Antibacterial activity was measured by the agar well diffusion method against four Gram positive and four Gram negative bacteria. The methanol extract of the fruit rind of C. indica showed the maximum DPPH free radical scavenging activity, superoxide anion radical scavenging activity, a high reducing capacity assessment and also had the highest total phenol content. There was a direct correlation between the phenol content and the antioxidant activity. The antibacterial activity of all the extracts was more pronounced on Gram positive bacteria than on Gram negative bacteria. Thus, the fruit rind of C. indica showed the best antioxidant and antibacterial activities.     

绿茶、桑叶和臭黄荆叶细粉水提液抑菌和抗氧化能力

探究绿茶、桑叶和臭黄荆叶3种植物干叶细粉水提液的抑菌和抗氧化能力。采用当量法测定3种原料中黄酮、多酚含量,二倍稀释法测定水提液对大肠杆菌、金黄色葡萄球菌的最小抑菌浓度和最小杀菌浓度,牛津杯法分析原料的抑菌活性。利用分光光度法研究3种水提液及其两两等比混合后的DPPH自由基清除率、羟自由基清除率和Fe²⁺螯合能力。结果表明,绿茶粉中水溶性黄酮、多酚含量最高,分别为62. 22、133. 82 mg/g,桑叶粉次之,臭黄荆叶粉最少。绿茶、桑叶和臭黄荆叶细粉在DPPH自由基清除率、羟自由基清除率和Fe²⁺螯合能力方面无协同作用,但黄酮、多酚含量与其抑菌和抗氧化活性间存在显著的量效关系(P <0. 05)。因此,绿茶、桑叶和臭黄荆叶细粉水提液抑菌和抗氧化能力依次减弱,且三者抗氧化活性没有协同增效作用。     

蜂胶中总酚提取纯化工艺及抗氧化活性研究

为研究西藏蜂胶抗氧化活性,评估开发潜力,分析了西藏蜂胶及其模拟消化液的抗氧化成分（总酚和总黄酮）和活性（还原力、羟自由基清除能力（·OH清除率）、1,1-二苯基-2-三硝基苯肼自由基清除率（DPPH·清除率）、金属离子螯合率和脂质过氧化抑制率）。结果表明,西藏蜂胶总酚和总黄酮含量分别为7.02%和10.05%。模拟消化液的总酚和总黄酮含量持续降低,模拟胃液（消化2 h）总酚和总黄酮含量分别为0.43%和6.43%,模拟肠液（消化2 h）则为0.32%和5.11%。西藏蜂胶在1 mg/mL时,还原力、·OH清除率、DPPH·清除率、金属离子螯合率和脂质过氧化抑制率达到最高值,分别为0.35、96.60%、92.53%、19.96%和97.01%。模拟胃液还原力和DPPH·清除率的最高值比未消化时升高,分别为0.39和95.69%。·OH清除率、金属离子螯合率和脂质过氧化抑制率较未消化时降低。模拟肠液·OH清除率、金属离子螯合率和脂质过氧化抑制率较模拟胃液提高,最高值分别为99.72%、69.26% 和80.69%;还原力和DPPH·清除率则降低,但DPPH·最高清除率仍有74.74%。综上所述,西藏蜂胶具有较好的体外抗氧化活性,胃肠模拟消化对抗氧化各指标均有显著影响,各指标的变化趋势不一致,但多个指标仍有较好表现。西藏蜂胶可作为一种天然抗氧化剂进行后续研发。     

Antioxidant activity of Indian propolis and its chemical constituents

We report for the first time the antioxidant activity of the aqueous and ethanol extracts of Indian propolis (AEP and EEP, respectively). The antioxidant activity was measured by chemical and electrochemical assays. Reducing power and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were the chemical assays, whereas, cyclic voltammetry was used as the electrochemical assay. In all these assays, AEP showed significantly greater activity over EEP; which is in contradiction with the previous reports of propolis from other countries. This may be due to its higher polyphenol content. Hence aqueous extract may well be a substitute of organic solvent extracts of propolis. Moreover, two flavonoids, pinocembrin (1) and galangin (2) were isolated from EEP; among which (2) showed high DPPH radical scavenging activity. Thus Indian propolis, being a rich source of natural antioxidants, may be used in the prevention of various free radicals related diseases.     

不同处理工艺对玫瑰花中抗氧化物质含量及抗氧化活性的影响

目的 研究不同处理工艺对平阴玫瑰中总黄酮、芦丁、总多酚含量及抗氧化活性的影响。方法 对干花直接提取、干花超微粉碎提取以及鲜花冷冻干燥提取3种不同处理工艺的平阴玫瑰进行水提,采用分光光度法测定水提液中总黄酮、总多酚的含量,高效液相色谱法测定水提液中芦丁含量,并对3种不同处理工艺的水提液进行1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基清除、羟自由基清除以及超氧阴离子清除能力的研究。结果 3种不同工艺处理的玫瑰花总黄酮含量、芦丁含量、总多酚含量及抗氧化活性均为：鲜花冷冻干燥>干花超微粉碎>干花直接提取。结论 经冷冻干燥处理后的平阴玫瑰抗氧化性物质含量及抗氧化活性均有升高,为玫瑰花抗氧化应用提供依据。     

Antioxidant activity and polyphenol contents in Brazilian green propolis extracts prepared with the use of ethanol and water as solvents in different pH values

Propolis is a natural product with a variable and complex chemical composition associated with its high concentration on polyphenolic compounds. The effect of pH variation (2.0, 3.0, 4.3, 6.0 and 8.0) during aqueous and ethanolic propolis extraction was studied for up to 10 days. Total phenols and flavonoids contents were measured for the extracts by spectrophotometric assays. Antioxidant activity was measured by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and ferric thiocyanate (FTC) methods. The best time of extraction was up to 5 days for all samples. Basic aqueous extracts (pH 8.0) resulted in a higher concentration of compounds than the extract without pH modification, reaching an increase of 160% in flavonoids and 25% in phenols. Ethanolic extracts with pH variation resulted in an extract with 50% less polyphenols and 6% less flavonoids than extract without pH modification. The antioxidant activity was highest for ethanolic extract at pH 4.3 and aqueous extract at pH 8.0 – almost 90% and 45%, respectively, in DPPH method – and was related to the level of polyphenols by Pearson's correlations.     

啤酒花活性成分与抗氧化活性的相关性

以3 个品种的萨斯特啤酒花为原料,比较了其石油醚、氯仿、乙酸乙酯、正丁醇和水相等不同极性溶剂提取物中α-酸、β-酸、总黄酮和总多酚的含量,采用?OH、1,1-二苯基-2-三硝基苯肼自由基、β-胡萝卜素-亚油酸3 种不同的抗氧化活性评价体系对各极性溶剂提取物的抗氧化活性进行了研究,并与其活性成分的含量进行了相关性分析。结果表明,啤酒花各极性部位均具有不同程度的抗氧化活性。α-酸、β-酸在石油醚相中含量较高,在3 个啤酒花样品中的含量范围分别为α-酸444.29～583.81 mg/g、β-酸131.83～293.19 mg/g,在氯仿相中含量相对较低,其余提取物中均未检出;相关性研究表明α-酸、β-酸是石油醚和氯仿相抗氧化活性的主要物质基础。中等极性和极性较大溶剂提取物中啤酒花总黄酮、总多酚含量较高,相关性研究也表明黄酮、多酚类物质是这类提取物抗氧化活性的主要物质基础;其中,3 个啤酒花样品中总黄酮、总多酚在乙酸乙酯相中含量最高,分别为20.43～24.13 mg/g和34.97～40.24 mg/g,正丁醇次之,分别为9.45～11.68 mg/g和12.12～19.14 mg/g。     

木瓜抗氧化活性研究

采用DPPH法、ABTS法和FRAP法三种测定法对木瓜叶和木瓜果实体外抗氧化活性进行综合评价,并分析其总多酚与总黄酮含量与抗氧化活性的关系。结果表明:木瓜6个提取物中,木瓜叶乙酸乙酯部位清除ABTS自由基及还原Fe3+（IC50=6.66μg/mL,TEAC=1293.25μmol/g）最强,其中,清除ABTS自由基活性和阳性对照BHT（IC50=6.56μg/mL）相当,还原Fe3+能力低于BHT（TEAC=2503.17μmol/g）;木瓜果实乙酸乙酯部位清除DPPH自由基（IC50=48.99μg/mL）能力最强,弱于阳性对照BHT（IC50=24.49μg/mL）。木瓜叶乙酸乙酯部位清除ABTS自由基及还原Fe3+的能力可能与其多酚、黄酮含量高有关,木瓜果实乙酸乙酯部位清除DPPH自由基的能力可能也与其多酚、黄酮含量高有关。      

短瓣金莲花不同提取部位的抗氧化活性

目的：研究短瓣金莲花的抗氧化活性部位。方法：将短瓣金莲花药材依次用石油醚、乙酸乙酯、95%乙醇、60%乙醇、30%乙醇和去离子水提取,采用紫外-可见分光光度法对不同溶剂提取部位的黄色素、总黄酮和总酚含量进行分析,并测试各提取部位对羟自由基（•OH）和1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基的清除作用以对其抗氧化活性进行研究。结果：短瓣金莲花石油醚提取部位的黄色素含量最高,为（11.37±0.07 ）mg/g;而60%乙醇提取部位总黄酮和总酚含量最高,分别为（213.21±1.12）mg/g和（121.75±0.58） mg/g,95%乙醇提取部位次之,分别为（200.47±0.65）mg/g和（105.19±0.61）mg/g。石油醚提取部位清除•OH能力最强,半抑制浓度（50% inhibiting concentration,IC50）为92.77 mg/L;95%乙醇提取部位清除DPPH自由基能力最强,IC50为10.14 mg/L,60%乙醇提取部位次之,IC50为10.70 mg/L。结论：短瓣金莲花清除•OH能力与黄色素含量呈正相关性,而清除DPPH自由基能力与黄酮和多酚含量呈正相关性;短瓣金莲花的石油醚和95%乙醇提取部位是最佳的抗氧化活性部位,有待进一步深入研究。     

青钱柳叶活性成分的抗氧化活性及UPLC-QTOF-MS/MS分析

利用96孔板法测定青钱柳叶不同溶剂(水、70%乙醇、乙酸乙酯和正己烷)提取物中总酚、总黄酮含量及抗氧化活性(DPPH自由基清除能力、还原能力、总抗氧化能力),考察酚类物质含量与抗氧化活性的相关性,并采用超高效液相色谱-四极杆飞行时间串联质谱(ultra performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spetrometry,UPLC-QTOF-MS/MS)分析提取物中主要活性成分。结果表明:不同提取物中总酚、总黄酮含量及抗氧化活性存在显著性差异且70%乙醇溶液提取物表现出最高的总酚(219.01 mg GAE/g)、总黄酮含量(7.23 mg CE/g)及最强的DPPH自由基清除能力(35.46 mg TE/g)和还原能力(1.89 mmol Fe SO_4/g);总酚、总黄酮含量与DPPH自由基清除能力、还原能力之间呈正相关,与总抗氧化能力呈显著负相关,表明多酚类物质是青钱柳中主要的抗氧化剂。UPLC-QTOF-MS/MS分析70%乙醇溶液提取物并初步鉴定出22种化合物,包括2种有机酸、4种酚酸、5种黄酮、8种三萜皂苷类和3种酯类,其中酚酸和黄酮类化合物是主要的抗氧化活性成分,有机酸、三萜皂苷及酯类化合物可能是潜在的抗氧化活性成分。     

Antioxidant properties of commercial soft and hard winter wheats (Triticum aestivum L.) and their milling fractions

The total phenolic content (TPC), total antioxidant activity (TAA), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging capacity, inhibition of coupled oxidation in a β‐carotene–linoleate model system, iron(II) chelation activity and inhibition of copper‐induced oxidation of human low‐density lipoprotein (hLDL) cholesterol of 80% ethanolic extracts of soft and hard winter wheat samples and their milling fractions, namely flour, germ, bran and shorts, were investigated. Soft wheat extracts examined demonstrated higher TPC and TAA compared to those of hard wheat extracts. The germ fraction possessed the highest TPC, followed by bran, shorts, whole grain and flour for both wheat types examined. The TAA of both wheat types showed similar results except that shorts performed better than bran in this assay. Free radical scavenging properties of whole grain and milling fractions of both soft and hard wheat samples were examined against DPPH radical. The germ and flour fractions demonstrated the highest and lowest DPPH radical scavenging activity, respectively, among wheat fractions. Wheat extracts were also efficient in preventing bleaching of β‐carotene, which is also known to be free radical mediated. In the iron(II) chelation assay the flour extracts demonstrated excellent activity, while the germ extracts showed a weak activity. The trends were similar in both soft and hard wheat for the iron(II) chelation assay. Wheat extracts also inhibited copper‐induced oxidation of hLDL. In LDL oxidation assay, wheat extracts performed better than the reference antioxidant, ferulic acid. Thus wheat phenolics may serve as effective antioxidative components as measured by in vitro techniques. Copyright © 2005 Society of Chemical Industry     

响应面法优化蜂胶黄酮提取工艺及其抗氧化活性研究

采用响应面法对蜂胶黄酮提取工艺进行优化。以蜂胶为原料,基于单因素实验,以乙醇体积分数、液料比、提取时间和提取温度为相应因素、蜂胶黄酮提取率为响应值,采用四因素三水平的响应面分析法,确定最佳提取工艺条件为:液料比14:1（mL·g-1）、提取温度72.6℃、提取时间2.5h、乙醇浓度80%（v/v）,在此条件下理论提取率为33.9324%,与实测值基本相符,说明优化工艺可行。以VC为对照物,经DPPH法和铁氰化钾法验证蜂胶黄酮的抗氧化活性,发现蜂胶黄酮具有较强的清除DPPH自由基能力和还原能力,可作为优良的天然抗氧化剂资源。      

覆盆子不同极性溶剂提取物的抗氧化活性比较

为比较覆盆子不同极性溶剂提取物的抗氧化活性,分别用正丁醇、乙酸乙酯、丙酮、去离子水、50％乙醇和石油醚进行萃取,测定各提取物总多酚和总黄酮的含量,并通过清除DPPH自由基、ABTS自由基、羟基自由基和总还原能力4种体系对其体外抗氧化活性进行评价.结果显示,乙酸乙酯提取物中总多酚含量最高,50％乙醇提取物中总黄酮含量最高...     

不同加工方式对青稞中酚类物质的影响

为探明不同加工方式对青稞全谷物中酚类物质的影响,最大程度地保留抗氧化和降血糖活性物质。以海南昆仑17号青稞籽粒为实验材料,分别采用蒸制、煮制、炒制、微波、烤制、空气炸锅等六种加工方式对青稞籽粒进行热加工处理,分析加工前后青稞中游离多酚、结合多酚、游离黄酮和结合黄酮的含量,以及抗氧化和降血糖活性的变化。结果表明,不同加工方式制备的青稞多酚和黄酮含量存在一定程度上的差异。与未加工相比,其他加工方式所得青稞游离多酚和游离黄酮的含量均显著降低（P<0.05）（除炒制外）,结合多酚和结合黄酮的含量均升高。与未加工相比,蒸制和煮制的方式对青稞游离多酚含量的损失高达43.77%和67.85%,炒制使青稞结合黄酮含量增加38.10%。此外,不同加工方式的青稞多酚提取物具有较好的DPPH自由基清除能力和α-葡萄糖苷酶抑制活性,且清除和抑制能力在一定浓度范围内具有浓度依赖性。在六种加工方式中,炒制处理青稞游离和结合多酚提取物（5 mg/mL）的DPPH自由基清除率最高,分别为70.01%、54.52%,且其α-葡萄糖苷酶抑制率也最高,分别为84.84%、75.70%。因此,炒制处理可较好地保留热加工前全谷物青稞中酚类物质的含量,从而发挥抗氧化和降血糖作用。     

Anti-AGE activity of poplar-type propolis: mechanism of action of main phenolic compounds

This study aimed to compare the protective effect of two geographically distinct propolis against the formation of advanced glycation end products (AGEs). The polyphenol content of propolis extracts (EEPs) was analysed using HPLC-DAD-MS profiling and evaluated for their protective effects against pentosidine-like AGEs. Dicarbonyl trapping capacities of major EEP compounds were determined using a methylglyoxal scavenging in vitro assay. Both propolis samples were characterised with high levels of pinobanksin derivatives exhibiting strong anti-AGE properties. EEPs reduced AGE formation more effectively than well-known natural AGE inhibitors such as quercetin or chlorogenic acid. Individual evaluations of the five major compounds in EEPs showed that flavonoids strongly inhibit the formation of AGEs by trapping dicarbonyl intermediates, whereas compounds such as caffeic acid derivatives only act as antioxidant agents. Propolis is thus a promising candidate for the prevention and control of AGE-related chronic diseases.     

蜂胶不同溶剂萃取物组成和抗氧化性的研究

以蜂胶为原料,分别以甲醇、乙醇、氯仿、蒸馏水为溶剂进行萃取,测定各萃取物总酚与黄酮类物质的含量,通过测定还原能力,清除DPPH 自由基能力的测定来比较4 种不同萃取物的抗氧化性。结果表明：甲醇萃取物具有较强的抗氧化性。甲醇萃取物浓度为0.25mg/ml 时还原力高达1.162,且浓度为0.05mg/ml 时对DPPH 自由基清除率为64.676%。乙醇萃取物通过石油醚、氯仿、乙酸乙酯、丙酮依次分级萃取后所得到4 种萃取物各项指标测定结果表明,氯仿萃取了蜂胶乙醇萃取物中主要成分,但乙酸乙酯和丙酮萃取物的还原能力及清除DPPH 自由基清除能力较佳,在浓度为0.05mg/ml 时还原力分别为2.087 和1.798,DPPH自由基清除率达87.724% 和88.013%。     

两种松科植物松多酚体外抗氧化活性评价

以红松和红皮云杉两种松科植物的树皮为实验原料,采用三种体外抗氧化体系(还原能力、DPPH.清除能力、OH.清除能力)对比评价松多酚的抗氧化活性,通过测定树皮中多酚、原花青素、黄酮含量,分析抗氧化活性与松多酚组成之间的关系。结果表明,红松松多酚和红皮云杉松多酚具有较高的还原能力,可以有效地清除DPPH.和OH.。两种树皮中总酚和原花青素的含量较高,黄酮的含量相对较低。原花青素是松多酚重要组分,影响松多酚的抗氧化活性。松多酚具有较高的抗氧化活性,因此可以作为一种天然抗氧化剂,广泛应用在食品、化妆品、保健品和医药领域。      

不同品种甘薯叶提取物抗氧化及对α-葡萄糖苷酶抑制活性的研究

本研究旨在通过比较7个品种甘薯叶提取物的抗氧化活性和α-葡萄糖苷酶抑制活性,探讨甘薯叶抗氧化和降血糖的潜力。以甘薯叶为研究对象,测定其总多酚和总黄酮含量,体外实验评价其抗氧化活性(DPPH·清除能力、ABTS+·清除能力、·OH清除能力和还原能力)及对α-葡萄糖苷酶的抑制活性。结果表明7个品种甘薯叶提取物总多酚和总黄酮含量、抗氧化活性以及α-葡萄糖苷酶抑制活性具有明显差异。甘薯叶总多酚含量介于15.02~33.33 mg GAE/g DW,总黄酮含量介于1.06~3.11 mg RE/g DW。徐薯18、济薯18和龙薯9甘薯叶总多酚和总黄酮含量最高,品种间无统计学差异(P>0.05)。龙薯9自由基(DPPH·、ABTS+·、·OH)清除能力最强;济薯18还原能力最强;商薯19抑制α-葡萄糖苷酶活性最强。总多酚和总黄酮含量与抗氧化活性之间具有极显著的正相关性(P<0.01),而与α-葡萄糖苷酶抑制活性之间没有显著的相关性(P>0.05)。本研究表明甘薯叶是潜在抗氧化剂和α-葡萄糖苷酶抑制剂的优质来源,为甘薯种植和生产品种的选择提供理论依据。     

槟榔提取物不同部位的抗氧化性比较及成分研究

采用DPPH法、ABTS法和FRAP法3种测定法对槟榔提取物体外抗氧化活性进行综合评价,并分析其总多酚与总黄酮含量与抗氧化活性的关系。研究结果发现,槟榔提取物乙酸乙酸部位和正丁醇部位均有一定的抗氧化活性。其中乙酸乙酯部位清除DPPH自由基和ABTS+自由基的能力（IC50=14.60、2.04μg/m L）和还原Fe3+的能力（TEAC=4762.99μmol/g）均强于阳性对照BHT（DPPH方法:IC50=24.49μg/m L;ABTS方法:IC50=6.56μg/m L;FRAP方法:TEAC=2503.17μmol/g）,正丁醇部位清除DPPH自由基和ABTS+自由基的能力（IC50=44.32、7.62μg/m L）和还原Fe3+的能力（TEAC=1587.42μmol/g）均弱于阳性对照BHT,且乙酸乙酯部位总多酚和总黄酮含量均大于正丁醇部位。可见,乙酸乙酯部位清除DPPH自由基、ABTS+自由基及还原Fe3+的能力可能与其总多酚、总黄酮含量高有关。      

黑木耳的生物活性物质及其在食品行业的加工现状

为探索富锗木耳菌丝体不同溶剂提取物的体外抗氧化能力,以富锗木耳菌丝体为材料,通过水、70%乙醇和乙酸乙酯对富锗木耳菌丝体进行了物质提取,比较了不同提取物对超氧阴离子自由基、羟自由基和DPPH自由基的清除能力。采用隶属函数值评价了不同溶剂提取物的综合抗氧化能力,并对物质含量与抗氧化能力进行了相关性分析。结果表明：富锗木耳菌丝体有机锗含量为542.83 μg/g。不同溶剂提取物的提取率和物质含量均不同,水和乙醇提取物的提取率较高,水提取物中多糖含量最多,乙酸乙酯提取物中多酚和黄酮含量最多。不同溶剂提取物对自由基均有一定的清除能力,且随着提取物浓度的增加而增加。水提取物对超氧阴离子自由基清除率最强,当提取物浓度为9 mg/mL时,清除率最高为43.32%。70%乙醇提取物对羟自由基和DPPH自由基的清除效果最好,当提取物浓度为9 mg/mL时,清除率分别为70.10%和76.99%。多糖、多酚和黄酮在清除自由基中均发挥不同的作用,70%乙醇提取物的综合抗氧化能力最强。多糖、多酚和黄酮含量均与DPPH自由基清除率有显著（P<0.05）正相关。70%乙醇提取物中多酚含量与羟自由基清除率有显著（P<0.05）正相关。多糖、多酚及黄酮对超氧阴离子自由基的清除率均有显著（P<0.05）影响。富锗木耳菌丝体含有较高含量的有机锗,提取物对自由基具有一定的清除能力,具有较好的抗氧化性能。本研究对开发富锗木耳功能食品具有一定指导意义。