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1.
Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and individual phenolic compounds were determined in canihua collected at approx. 3850 m altitude. The TAC values varied among samples from 2.7 to 44.7 by the ferric reducing antioxidant power (FRAP) method and from 1.8 to 41 by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method expressed as micromol of Trolox equivalents/g dw. The content of TPH was 12.4-71.2 micromol gallic acid equivalents/g dw and that of the TF ranged between 2.2 and 11.4 micromol of catechin equivalents/g dw. The data obtained by the four methods showed several significant correlations. Prior to analysis by HPLC, the samples were subjected to acid hydrolysis and in the water-soluble extracts this led to an up to 20-fold increase in the TAC values in comparison with the values of the nonhydrolysed samples. HPLC analysis showed the presence of eight major compounds identified as catechin gallate, catechin, vanillic acid, kaempferol, ferulic acid, quercetin, resorcinol and 4-methylresorcinol. Their estimated contribution to the TAC value (FRAP method) indicated that resorcinols contributed most of the antioxidant capacity of the water-soluble extract. The results show that canihua is a potential source of natural antioxidant compounds and other bioactive compounds which can be important for human health.  相似文献   

2.
The cytoprotective effects of five flavonoids (quercetin, rutin, catechin, kaempferol and morin) and four hydroxycinnamic acids (caffeic, ferulic, sinapic and chlorogenic acids) were evaluated by the degree of protection they provided against H2O2-induced damage to human neuroblastoma SH-SY5Y cells. All compounds exhibited protection against H2O2-mediated cytotoxicity in a dose dependent manner. The concentration required to give a 50% reduction in cell death (EC50 value) were derived from their dose–response relationships. The cytoprotective activities of these phenolic compounds in the order of quercetin > caffeic acid > rutin > chlorogenic acid > catechin > ferulic acid > sinapic acid > morin > kaempferol. The EC50 values of the phenolic compounds were strongly related to their chemical structures. The EC50 values were compared with the antioxidant activities as determined by five different chemically based antioxidant assays [2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP) and lipid peroxidation inhibition capacity (LPIC)]. The ability of these phenolic compounds to protect from H2O2-induced SH-SY5Y cell death correlated (r 2 = 0.85) with their determined LPIC values and weakly (r 2 = 0.44) with their ABTS activities. There was no correlation between EC50 values and ORAC, FRAP or DPPH activities. The cytoprotection assay is a more biologically relevant measurement than the chemically defined antioxidant activity assays because it uses human cells as a substrate and therefore accounts for some aspects of uptake, metabolism and location of antioxidant compounds within cells.  相似文献   

3.
In this study, fifty‐one monofloral Sardinian honeys from ten various floral origins were screened for their phenolic content, antioxidant activity, colour and electrical conductivity. The total phenolic amounts have been evaluated by Folin–Ciocalteu method, whereas quantification of several phenolic compounds (phenolic acids and flavonoids) has been carried out by HPLC‐DAD technique. The richest sample in phenolic compounds resulted strawberry tree honey with about 40 mg GAE/100 g, as well FRAP test and DPPH˙ test confirm that antioxidant activity of strawberry tree honey extract exceed both honey extracts and synthetic antioxidants like BHA and BHT. Among the studied phenolic compounds a total of five phenolic acids (ferulic, syringic, trans‐cinnamic, chlorogenic and p‐hydroxycinnamic) and nine flavonoids (catechin, kaempferol, rutin, quercetin, luteolin, apigenin, galangin, pinocembrin and pinobanksin) were identified. Our results show good correlations between total polyphenol amount and antioxidant activity and between colour and electrical conductivity.  相似文献   

4.
滁菊的功能成分及其体外抗氧化活性   总被引:1,自引:0,他引:1  
为明确滁菊中抗氧化活性物质的含量及其抗氧化能力,对其进行进一步的开发利用,对滁菊(Chrysanthemum morifolium Ramat)酚类、多糖、类胡萝卜素提取物抗氧化能力及含量进行研究。结果表明:滁菊总酚和黄酮含量较高,分别为53.67 mg/g和70.32 mg/g,高于大洋菊等菊花;多糖和类胡萝卜素含量较低。3 种提取物中,酚类抗氧化能力最强,对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)和2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基的清除能力分别为208.79 mmol/g和160.23 mmol/g,对Fe3+的还原能力达到238.35 mmol/g,高于杭白菊等菊花。采用高效液相色谱法测定了滁菊酚类及类胡萝卜素单体组成,初步鉴定出滁菊含有绿原酸、儿茶素、咖啡酸、阿魏酸、金丝桃苷、槲皮素6 种单体酚,以及叶黄素和β-类胡萝卜素2 种类胡萝卜素单体。酚类物质中绿原酸含量最高,达到813.21 mg/g;金丝桃苷次之,达到408.17 mg/g;类胡萝卜素中叶黄素含量最高,为78.6 mg/g。在不考虑协同作用情况下,酚类物质中绿原酸对Fe3+还原能力、DPPH及ABTS阳离子自由基清除能力的贡献均最大,类胡萝卜素中叶黄素对DPPH自由基的清除能力贡献最大。  相似文献   

5.
This study aimed to evaluate the effects of storage period (0, 2, 4, and 6 months) and temperature (15 °C, 25 °C, and 35 °C) on the germination, vigor, technological properties, starch digestion, and phenolic compound content of mung beans. The germination, vigor, protein solubility, inhibition of the ABTS radicals, and the total free and bound phenolic compound content reduced while cooking time, leached solids, and electrical conductivity increased during storage. Minor changes were observed in grains stored at 15 °C. Starch digestion was higher in stored grains than in freshly harvested beans; however, it decreased on increasing the temperature. The content of bound gallic acid, bound chlorogenic acid, free and bound ferulic acid, free and bound rutin, and free and bound quercetin contents reduced after storage. In contrast, the content of bound caffeic acid, bound vanillic acid, bound myricetin, free coumaric acid, and free catechin contents increased after storage at 15 °C. These results suggested that mung beans could be cooled at 15 °C to reduce the detrimental effects of storage and maintain the nutritional value and germination viability.  相似文献   

6.
Industrial processing modified the polyphenol content, composition and antioxidant activity of the yerba mate extracts. Pre-dried leaves were the most appropriate raw material combining maximum activity with high polyphenol content. Chlorogenic acid and its derivatives were the major components of the phenolic fraction but we also identified caffeic, rutin and quercetin.Yerba mate extracts inhibited malonedialdehyde formation in sunflower oil (20 μmol/kg) and conjugated dienes production in oil/water emulsions (60 μmol/kg). Enhancing the dose to 60 μmol/kg reduced 27.8% the extract’s activity in oil.The relationship between polyphenol composition and antioxidant activity of a mixture of caffeic, chlorogenic, kaempferol, quercetin and rutin was satisfactorily predicted with a polynomial model. Results showed that quercetin was the highest contributor to the linear term followed by kaempferol and caffeic acid while rutin and chlorogenic acid inputs were the lowest. The model detected five synergistic and six antagonistic effects.  相似文献   

7.
以黑脉羊肚菌为原料,分离提取羊肚菌多酚(游离酚和结合酚),对提取物中酚类物质的含量及抗氧化活性进行研究,并采用超高效液相色谱-二极管阵列检测器/电喷雾飞行时间质谱对黑脉羊肚菌游离酚和结合酚的组分进行鉴定。结果表明,黑脉羊肚菌多酚主要为游离酚,且游离酚的DPPH自由基清除率、还原力及氧自由基吸收能力都显著强于结合酚(P0.05),而两者清除ABTS~+·能力相当。从黑脉羊肚菌多酚中鉴定出15种组分,分别是没食子酸、焦性没食子酸、原儿茶酸、对羟基苯甲酸、儿茶素、咖啡酸、绿原酸、荭草素、芦丁、金丝桃苷、白藜芦醇、木犀草素、槲皮素、肉桂酸、阿魏酸,游离酚提取物有15种组分,结合酚提取物有14种组分。  相似文献   

8.
Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p‐coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59 mg kg?1 fresh weight, while naringenin levels were lower than 12.55 mg kg?1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32 mg kg?1 fresh weight, followed by caffeic acid, while p‐coumaric and ferulic acids showed similar concentrations lower than 5 mg kg?1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50 mg kg?1 fresh weight), while the concentration in the other varieties was between 50 and 30 mg kg?1, with the exception of Liso (less than 20 mg kg?1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry  相似文献   

9.
15 种柑橘果实主要酚类物质的体外抗氧化活性比较   总被引:1,自引:0,他引:1  
张华  周志钦  席万鹏 《食品科学》2015,36(11):64-70
为了明确柑橘果实主要酚类物质单体的抗氧化活性差异,利用1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)法、2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(2,2’-azino-bis(3-ethylbenzthiozoline-6)-sulphonic acid,ABTS)法、铁离子还原(ferric reducing/antioxidant power,FRAP)法3 种离线法,以及两种在线高效液相色谱-DPPH/ABTS(high performance liquid chromatography-DPPH/ABTS,HPLC-DPPH/ABTS)柱后衍生系统联用技术分别对15 种柑橘果实主要酚类物质单体的抗氧化活性进行测定和比较分析。结果表明:抗氧化活性综合(antioxidant potency composite,APC)指数可有效反应各单体的抗氧化活性,柑橘果实15 种主要酚类物质抗氧化活性明显不同,4 种酚酸的抗氧化活性最强,依次为:没食子酸(92.32%)>咖啡酸(85.29%)>绿原酸(69.75%)>阿魏酸(50.97%)。圣草酚(39.38%)、圣草次苷(39.36%)和芦丁(27.42%)的抗氧化活性中等,橙皮素、柚皮素、地奥司明、橙皮苷、川陈皮素、甜橙黄酮、柚皮苷和橘皮素的抗氧化活性较小(<5%)。酚羟基的糖基化或甲基化会都降低柑橘酚类物质的自由基清除能力,酚羟基数目越多,抗氧化活性越强。  相似文献   

10.
超微粉碎对香菇多酚组成及抗氧化活性的影响   总被引:3,自引:0,他引:3  
将鲜香菇分为伞、柄后进行适当干燥,利用超微粉碎得到不同粒径的香菇伞粉和香菇柄粉,比较气流超微粉碎和纳米超微粉碎与普通粉碎处理在香菇伞粉和柄粉多酚溶出率、组成及抗氧化活性之间的差异。结果表明:与普通粉碎相比,超微粉碎可以使香菇伞粉总酚溶出率提高13%;通过高效液相色谱(high performanceliquid chromatography,HPLC)检测分析,香菇多酚类物质主要为没食子酸、儿茶素、咖啡酸、芦丁、阿魏酸和槲皮素,其中游离酚以没食子酸和儿茶素为主,结合酚以没食子酸、儿茶素和槲皮素为主。抗氧化能力评价中,气流超微粉碎能明显改善香菇多酚的还原力、2,2’-联氨-双-(3-乙基-苯并噻唑啉-6-磺酸)二氨盐(2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid),ABTS)自由基清除力和总氧自由基吸收能力(oxygen radical absorbancecapacity,ORAC);纳米超微粉碎能够提高柄粉多酚的1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除力。超微粉碎能够提高香菇多酚的溶出率及抗氧化活性,可以作为以香菇为原料开发功能性食品的一种前处理加工手段。  相似文献   

11.
Antioxidative activities of different phenolic compounds (catechin, caffeic acid, ferulic acid and tannic acid) at various levels were determined by different assays. Among all the phenolic compounds tested, tannic acid exhibited the highest 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and ferric reducing antioxidant power (FRAP). Nevertheless, catechin showed the highest metal chelating activity (P < 0.05), whereas caffeic acid had the highest lipoxygenase (LOX) inhibitory activity (P < 0.05). The impact of different phenolic compounds at a level of 100 mg/l on lipid oxidation of menhaden oil-in-water emulsion and mackerel mince was investigated. Tannic acid showed the highest efficacy in retardation of lipid oxidation for both model systems as evidenced by the lower peroxide value (PV), conjugated diene (CD) and thiobarbituric acid-reactive substances (TBARS) values. This was also related with the lower non-heme iron content in tannic acid treated samples. Tannic acid was therefore considered as the most potential natural antioxidant for controlling oxidation of fish oil-in-water emulsion and fish mince, whereas ferulic acid seemed to possess the lowest preventive effect on lipid oxidation.  相似文献   

12.
The antioxidant activity of grape juices, wines made from the same lot as juices and their major polyphenolic constituents was measured by the inhibition of lipid oxidation (ferric-thiocyanate) and free radical scavenging (2,2-diphenyl-1-picrylhydrazyl) methods. dl-α-Tocopherol and 3-tertiary-butyl-4-hydroxyanisole (BHA) were used as references. The inhibition of lipid oxidation of the standards followed the order: rutin = ferulic acid > tannic acid = gallic acid = resveratrol > BHA = quercetin > dl-α-tocopherol > caffeic acid. Meanwhile, the free radical scavenging activity of gallic acid was the highest, tannic acid, caffeic acid, quercetin, BHA and rutin activities were intermediate and that for ferulic acid, dl-α-tocopherol and resveratrol were the lowest. Wines had higher activity than the corresponding grape juices and red wine showed the strongest activity among the grape products tested. The antioxidant activity of the samples seems to be based on their free radical scavenging capacity.  相似文献   

13.
草莓、黑莓、蓝莓中多酚类物质及其抗氧化活性研究   总被引:5,自引:0,他引:5  
研究草莓、黑莓、蓝莓3种小浆果的总酚、总黄酮、原花青素含量及其总抗氧化能力。结果表明:蓝莓全果的总酚、总黄酮、原花青素含量在所测3种浆果全果中最高,分别为9.44mg没食子酸/g干质量、36.08mg芦丁/g干质量、24.38mg儿茶素/g干质量;其总抗氧化能力也最强,达14.98mmol Trolox/100g干质量。草莓的总酚、总黄酮、原花青素含量则最低,抗氧化能力也最弱。此外,3种浆果果渣中的总酚、总黄酮、原花青素含量以及总抗氧化能力均高于全果和果汁,即果渣>全果>果汁。总酚含量、总黄酮含量以及原花青素含量与总抗氧化能力之间的相关性分析表明,总酚含量与总抗氧化能力之间存在显著线性相关,相关系数r达到0.9704,表明酚类物质是其抗氧化作用的主要物质基础。  相似文献   

14.
The total antioxidant capacity (TAC) of bovine milk, whey, and low-molecular-weight (LMW) fractions of whey was investigated using spectrophotometric methods including an ABTS-based method (reduction of the cation radical of 2,2′-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)) and a FRAP method (reduction of Fe3+). Significant antioxidant capacity in milk and whey was demonstrated by the ABTS method (TAC(ABTS)), and it apparently increased with increasing pH. TAC (ABTS) was several-fold higher in milk than in whey, which had a slightly higher TAC than a LMW fraction prepared from it. Also the FRAP method could be used to demonstrate TAC in whey, although the low pH necessary for this method led to some protein precipitation. Most of the ferric-reducing activity of whey was found in the LMW fraction. The TAC values obtained using these methods were also compared to those obtained using a newly developed flow-injection amperometric (FIAmp) procedure for LMW fractions. High correlations were found for the TAC values of LMW samples obtained by the ABTS, FRAP and FIAmp methods (R2>0.8, P<0.001). Furthermore, to identify the major antioxidants in the LMW fraction, it was treated by uricase. Since most of the TAC (using ABTS, FRAP and FIAmp methods) was removed by uricase treatment, it could be concluded that urate is the major antioxidant in the LMW fraction. Also the effect of heat treatment on TAC in milk and whey was monitored. After heating of whey at 63°C for 1 h, TAC(ABTS) tended to increase by at least 20%, while TAC(FRAP) was not significantly changed. In milk, TAC(ABTS) remained constant during the same heat treatment. It is concluded that the methods tested gave the most reliable results for the LMW fraction of whey and that the use of several methods is necessary to characterise the antioxidant capacity of milk.  相似文献   

15.
In the present study, betalains content, phenolic composition, and antioxidant activity of different parts of red beet (Beta vulgaris L. conditiva) (i.e., roots and stems) were compared. Crude extract of root showed the highest betalain content with a maximum of 53 ± 4 mg betanin eq and 46 ± 3 mg vulgaxantin I eq g?1 of extract stems showed higher total phenolic concentration than roots, ranging between 2.0 ± 0.4 and 14.6 ± 0.5 mg gallic acid eq?1 of extract. Chemical composition was analyzed using LC-MS. Betalains (vulgaxanthin I, betanin, and isobetanin) and phenolics (gallic acid, ferulic acid, chlorogenic acid, caffeic acid, vanillic acid, syringic acid, ellagic acid myricetin, quercetin, rutin, kampferol) were identified in roots and stems. Betalain extract obtained from roots showed higher antioxidant activity than extract obtained from stems.  相似文献   

16.
李晓英  薛梅  樊汶樵 《食品科学》2017,38(3):142-147
比较蓝莓花、嫩茎、嫩叶及老叶总多酚、总黄酮、原花青素的含量,并研究其抗氧化性能差异。结果表明:嫩叶中总多酚含量最高,为43.77 mg GAE/g(以干质量计,下同),分别是花、嫩茎和老叶的3.45、1.42、1.12倍;老叶中总黄酮、原花青素含量最高,为68.01 mg RE/g、23.29 mg CAE/g,分别是花的2.57倍和4.61倍、嫩茎的1.79倍和1.23倍、嫩叶的1.03倍和1.98倍。抗氧化性能中,老叶的铁还原能力最大,其次是嫩茎和花,嫩叶较差;清除·OH的能力为嫩茎嫩叶花老叶;清除DPPH自由基能力和总抗氧化能力均为嫩茎嫩叶老叶花甲醇提取物,均高于对照品;蓝莓各部分提取物对DPPH自由基的清除能力最强,总抗氧化能力次之,清除·OH能力和铁还原能力较差。  相似文献   

17.
In order to understand how interaction of individual phenolics contributes to the total antioxidant capacity, we quantitatively measured antioxidant capacity of various phenolics in different combinations, using ABTS radical-scavenging ability in a model system. Selected phenolics included in this study were those often found in fruits and vegetables, such as catechin, chlorogenic acid, cyanidin, cyanidin 3-glucoside, cyanidin 3-rutinoside, epicatechin, peonidin, peonidin 3-glucoside, quercetin, quercetin 3-glucoside, quercetin 3-galactoside and quercetin 3-rutinoside. Individual phenolics showed their characteristic antioxidant capacities, while the mixtures, with two or three phenolics combined revealed that the summation of antioxidant capacities of individual phenolics led to total antioxidant capacity. Therefore, it can be concluded that there was no synergistic effect among the phenolics studied. Only an additive effect of antioxidant capacity was observed.  相似文献   

18.
The mung bean (Vigna radiata) sprout is a popular fresh vegetable in many parts of the world. In this study, the dynamic change of ascorbic acid, phenolic composition and antioxidant capacity were evaluated in green and black mung bean sprouts. Germination increased ascorbic acid, total phenolic content and antioxidant capacity in both mung beans. The green mung bean sprout generally had higher ascorbic acid, total phenolic content and antioxidant capacity than the black mung bean sprout. Most phenolic compounds, such as caffeic acid, catechin, ferulic acid, gallic acid and rutin, were found to gradually increase after germination. Therefore, mung bean sprouts, especially green mung bean sprout possessing high level of antioxidant phytochemicals, can be valuable functional vegetables and good sources of natural antioxidants.  相似文献   

19.
Bitter bean (Parkia speciosa), also known as petai, is a popular non-timber forest product. Traditionally, its fruits are consumed as vegetables and herbal medicines in Malaysia. The present study aimed to evaluate the antioxidant activities of aqueous and ethanol extracts of P. speciosa empty pods using various antioxidant assays, as well as examining their polyphenolic constituent contents. Results showed that with the exception of superoxide radical scavenging activity, ethanol extracts possessed stronger DPPH and ABTS radical scavenging, anti-lipid peroxidation, metal chelating and reducing power activities than aqueous extracts. It was found to contain a higher level of total flavonoids and total phenols than aqueous extracts. The major polyphenolic constituents present in these extracts were gallic acid, catechin, ellagic acid, and quercetin. Although aqueous extracts contained a higher level in gallic acid, its catechin, ellagic acid, and quercetin contents were lower than ethanol extracts. Taken together, the higher amount of polyphenolic compounds present in ethanol extracts could have contributed to its stronger antioxidant activities than aqueous extracts; these results also provided the chemical basis for certain health benefits claimed of P. speciosa empty pods in folk medicine and as foods.  相似文献   

20.
Novel postharvest technology not only preserves the freshness of fruits and vegetables, but also triggers the biosynthesis of antioxidant compounds as a secondary response. This study examined the browning and antioxidant properties of button mushrooms (Agaricus bisporus) treated with UV‐C irradiation in combination with cold storage. Three sample preparation methods for antioxidant activity analysis, simulative gastrointestinal digestion (GAR), direct evaluation (QUENCHER) and traditional solvent extraction (TSE), were used to evaluate the samples, and followed analysing by both FRAP and ABTS assays. Broadly, the results indicated that, following an initial increase, UV‐C irradiation suppressed browning during a cold storage period of 18 days. And the total phenolic content of the treated mushrooms were higher than that of the control, while the ascorbic acid content decreased sharply during storage, and UV‐C treatment had negative effects on ascorbic acid content. Results from the QUENCHER and GAR methods showed that UV‐C treatment significantly increases the total antioxidant capacity (TAC) of mushrooms throughout the entire storage period, and have a larger magnitude than that of TSE method. In conclusion, the combination of UV‐C irradiation and cold storage showed great potential for improving mushroom quality as a new postharvest technology.  相似文献   

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