黑果腺肋花楸花色苷提取工艺优化及其抗氧化活性和组成鉴定

目的：优化超声波辅助提取黑果腺肋花楸花色苷的条件,测定花色苷的抗氧化能力,鉴定黑果腺肋花楸花色苷提取物的组成成分。方法：采用响应面法优化花色苷提取条件,通过1,1-二苯基-2-三硝基苯肼自由基清除能力、2,2’-联氨-双（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基清除能力及Fe3＋还原能力方法评价其抗氧化能力,高效液相色谱-质谱联用法进行成分分析。结果表明：提取温度60?℃、超声功率100?W、料液比1∶30（g/mL）、超声时间31?min、乙醇体积分数64%和pH?2.0时为最优提取条件,此时黑果腺肋花楸花色苷含量可达（3.61±0.01）mg/g。体外抗氧化实验表明,在相同质量浓度条件下,黑果腺肋花楸花色苷提取物的抗氧化活性明显高于VC。组分鉴定表明黑果腺肋花楸花色苷提取物中共有6?种花色苷,其中矢车菊-己糖苷二聚体和矢车菊-3,5-二己糖苷为新检测出的2?种花色苷。     

麦胚清蛋白抗氧化肽的筛选及对细胞氧化损伤的保护作用

本研究运用超滤与凝胶层析等分离纯化技术逐级分离麦胚清蛋白中性蛋白酶酶解产物,以氧化自由基吸收能力（oxygen radical absorbance capacity,ORAC）与2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)（2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid),ABTS）阳离子自由基清除率为评价指标,筛选具有较高抗氧化活性的产物组分,并以该组分为研究对象,利用液相色谱-串联质谱结合PeptideRanker数据库活性预测技术筛选出具有高抗氧化活性的小肽,并通过高糖诱导血管平滑肌细胞（vascular smooth muscle cells,VSMCs）及H2O2诱导HepG2细胞与VSMCs建立细胞氧化应激模型,评价小肽对细胞氧化损伤的保护作用。结果表明,经超滤与层析筛选出分子质量较小的V组分抗氧化活性最高,液相色谱-串联质谱鉴定出该组分主要由20 个小肽组成,PeptideRanker预测与抗氧化实验验证发现肽序列LNYPPY（765.3 Da）抗氧化活性最高（ORAC 3.01 μmol TE/μmol）、ABTS阳离子自由基清除率95.58%）。肽序列LNYPPY对H2O2诱导的HepG2细胞和VSMCs氧化损伤具有很好的保护作用,但对高糖诱导的VSMCs异常增殖以及活性氧水平上升无明显影响。综上,肽LNYPPY具有良好的体外抗氧化活性,且对H2O2诱导的细胞氧化损伤具有保护作用,研究可为麦胚清蛋白的开发利用提供重要的理论参考。     

5’-磷酸腺苷（5’-AMP）体外抗氧化作用的研究

目的：研究5’-磷酸胞苷（5’-AMP）清除活性氧自由基能力及对体外氧化损伤脾细胞的损伤修复能力;方法：采用化学比色法测定5’-AMP清除羟自由基和DPPH自由基的能力,建立H2O2氧化损伤体外培养脾细胞模型,用MTT法检测5’-AMP的修复作用,以评价5’-磷酸腺苷（5’-AMP）的体外抗氧化能力;结果：5’-磷酸腺苷具有剂量依赖性的清除羟自由基和修复脾细胞氧化损伤的能力,但是5’-AMP的DPPH清除能力比较弱。20mmol／L5’-AMP的羟自由基清除能力高达53．009％,而DPPH清除率为17．190％;10mmol／L5＇-AMP清除羟自由基和DPPH自由基的能力分别相当于7．5mmol／L Vc和0．02mm01／LVc;与对照组相比,添加0．5,1,5,10mmol／L5’-AMP均能极显著（P〈0．01）地修复H2O2诱导的脾细胞氧化损伤,其中10mmol／L5’-AMP作用最强;结论：5’-磷酸腺苷具有显著的抗氧化作用。     

红曲色素的抗氧化活性及对HepG2氧化损伤的保护作用研究

目的 研究纯化后的红曲色素(monascus pigments,MPs)抗氧化活性及对HepG2细胞氧化损伤的修复作用。方法 以红曲米粉为原料,对其含有的MPs进行提取、纯化和鉴定。通过测定MPs的总抗氧化能力、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt, ABTS]阳离子自由基清除率评估了其抗氧化活性。同时,选用0.20 mmol/L的H2O2建立氧化应激模型,探索不同浓度MPs对细胞氧化损伤的保护机制。结果 纯化后的MPs含有4种MPs单体,分别为安卡红曲黄素、红曲玉红素、红曲素和潘红胺。MPs的总抗氧化能力（total antioxidant capacity,T-AOC）、DPPH自由基和ABTS阳离子自由基清除率与其浓度呈正相关。用不同浓度的MPs预处理后,与MC组相比,较低浓度（10 μg/mL）的MPs能显著提高细胞的存活率,但较高浓度的MPs (20 μg/mL)显著降低了细胞的存活率,这可能是H2O2与MPs协同作用导致的。随着MPs浓度增加,细胞中活性氧(reactive oxygen species,ROS)累积量逐渐减少。当MPs浓度为20 μg/mL时,过氧化氢酶(catalase,CAT)和超氧化物歧化酶(superoxide dismutase,SOD)活性分别从14.75 U/mL±0.04 U/mL、3.87 U/mL±0.09 U/mL提升至15.25 U/mL±0.05 U/mL、8.28 U/mL±0.68 U/mL。结论 MPs有较强的自由基清除能力,对H2O2诱导的氧化损伤有保护作用,这可能是与MPs提高了抗氧化酶活性,降低了细胞内ROS累积量有关。     

稠李花色苷的纯化及体外抗氧化活性

目的：建立AB-8大孔树脂纯化稠李花色苷的方法,并检测稠李花色苷体外抗氧化活性。方法：通过AB-8大孔树脂对稠李花色苷的动态吸附与解吸条件优化,确定最佳纯化条件;采用四唑氮蓝（nitroblue tetrazolium,NBT）光化还原法测定花色苷体外抗氧化活性,2’,7’-二氢二氯荧光素二乙酸酯（2’,7’-dichlorodihydrofluorescein diacetate,DCFH-DA）法观察花色苷对H2O2诱导的N2A细胞氧化损伤的保护作用。结果：稠李花色苷的最佳动态纯化条件是：吸附流速0.01 mL/s,粗提液质量浓度8 mg/mL,过柱次数2 次;解吸剂乙醇体积分数70%,流速0.01 mL/s,pH 3,纯化之后稠李花色苷的色价为57.1,纯化了16.31 倍;NBT实验结果表明,稠李花色苷具有清除超氧阴离子自由基的能力,且具有较好的剂量-效应关系;0.025 mg/mL的稠李花色苷能够保护H2O2损伤的N2A细胞,0.05 mg/mL的稠李花色苷能够降低细胞内活性氧水平。结论：AB-8大孔树脂是纯化稠李花色苷的一种有效方法,稠李花色苷在一定质量浓度范围内具有较好的体外抗氧化活性。     

红凤菜花色苷提取物的热降解动力学与抗氧化活性研究

对红凤菜花色苷水提取物的粗提物和纯化物分别进行了热稳定性的研究,并以DPPH法、ABTS法、邻二氮菲-Fe2+法评价了它们的抗氧化活性。结果表明:红凤菜花色苷提取物的热降解遵循一级反应动力学规律。在65～95℃范围内,红凤菜花色苷粗提物和纯化物的半衰期t1/2分别为3.55～1.73 h和26.52～2.92 h,反应活化能Ea分别为45.45 kJ/mol和101.31 kJ/mol。红凤菜花色苷提取物清除不同自由基的能力由大到小依次为羟自由基 DPPH自由基 ABTS自由基,其中对羟自由基清除率优于维生素C对照。粗提物、纯化物和维生素C清除羟自由基的EC50分别为1.17 mg/mL、0.57 mg/mL、2.65 mg/mL,清除DPPH自由基的EC50分别为0.50 mg/mL、0.15 mg/mL、49.50μg/mL,清除ABTS自由基的EC50分别为0.72 mg/mL、0.24 mg/mL、49.62μg/mL。纯化后的花色苷提取物热稳定性和抗氧化活性均优于粗提物。     

紫薯花青素体外抗氧化及对H2O2诱导HepG2细胞氧化损伤的保护作用

目的：研究紫薯花青素的体外抗氧化作用,建立H2O2诱导HepG2细胞氧化损伤模型,初步评价紫薯花青素的抗氧化应激作用。方法：紫薯干粉经过提取、纯化制得紫薯花青素干粉,分别测定紫薯花青素的总还原力、对羟自由基（·OH）、超氧阴离子自由基（O2－•）的清除能力以及对大鼠红细胞溶血的保护作用。建立H2O2诱导HepG2细胞氧化损伤模型,采用四甲基偶氮唑蓝（methyl thiazolyl tetrazolium,MTT）法检测不同质量浓度紫薯花青素对HepG2细胞氧化损伤的保护作用。结果：紫薯花青素的还原力和VC基本相当;紫薯花青素对·OH有很好的清除效果,在实验浓度范围内有明显的剂量-效应关系;随紫薯花青素浓度的升高,对O2－•的清除作用增强,呈现良好的量-效关系,单位浓度的紫薯花青素对O2－•的清除作用比2,6-二叔丁基-4-甲基苯酚（butylated hydroxytoluene,BHT）效果好。不同质量浓度的紫薯花青素均可抑制H2O2诱导的大鼠红细胞溶血,且随着紫薯花青素质量浓度的升高,大鼠红细胞的溶血度降低,呈现良好的量-效关系。H2O2诱导的HepG2细胞氧化损伤模型中,50～1 600 μg/mL的紫薯花青素均能够抑制H2O2引起的HepG2细胞凋亡,当紫薯花青素质量浓度达到800 μg/mL时,HepG2细胞存活率为（88.03±7.48）%。结论：紫薯花青素具有良好的体外抗氧化作用,并对H2O2诱导HepG2细胞氧化损伤具有明显的保护作用,研究初步揭示了紫薯花青素具有体外抗氧化作用。     

‘蓓蕾’蓝靛果中花色苷组成鉴定及抗氧化能力比较分析

对蓝靛果中花色苷的组成进行鉴定,并对其抗氧化能力进行比较分析。实验以蓝靛果(‘蓓蕾’品种)为原料,采用有机溶剂60%乙醇(0.1%盐酸酸化)溶液,超声辅助提取90 min;利用D101大孔树脂对获得的粗提物进行纯化,之后冷冻干燥制得粉末物质。通过p H示差法和福林-酚法分别测定总花色苷含量和总多酚含量,分别为(353.35±0.79)、(474.01±2.12)mg/g;并用高效液相色谱-质谱联用法对花色苷组成进行鉴定,共发现11种花色苷,其中矢车菊-3-葡萄糖苷为主要花色苷(90.679%)。此外,实验还通过总抗氧化能力测定和2,2’-联氨-二(3-乙基苯并噻唑-6-磺酸)二铵盐自由基、1,1-二苯基-2-三硝基苯肼自由基清除能力测定,比较分析蓝靛果花色苷提取物、矢车菊-3-葡萄糖苷、VC的抗氧化能力,结果表明,3种物质的抗氧化能力排序为:矢车菊-3-葡萄糖苷花色苷提取物VC。     

利用AB-8大孔树脂纯化‘黑宝石’李果实花色苷的研究

本文以‘黑宝石’李果实为材料,实验通过AB-8大孔树脂静态和动态条件下的吸附和解吸优化了AB-8大孔树脂纯化花色苷的条件,同时对纯化前后花色苷的成份和含量及抗氧化能力的变化进行了研究。结果表明,最佳纯化工艺条件:以浓度0.015 mg/m L、p H3.5的提取液,流速1.0 m L/min进行上样;以流速0.5 m L/min、80%的乙醇进行洗脱。纯化花色苷的抗氧化能力有所提高,在浓度小于100μg/m L时,纯化花色苷对DPPH自由基的清除能力明显高于粗提物对DPPH自由基的清除能力;在浓度为10和15μg/m L时,纯化花色苷样品对ABTS+·自由基的清除能力分别为粗花色苷的1.24和1.07倍。‘黑宝石’李中的花色苷为矢车菊素-3-葡萄糖苷和矢车菊素-3-芸香糖苷,纯化后两种花色苷单体的含量分别达到261.6 mg/L和26.6 mg/L。研究成果将为李花色苷性质研究、李资源开发和深加工转化提供理论依据和技术支撑。      

稠李花色苷酶法制备及对H2O2诱导大鼠胰岛素瘤细胞损伤的保护作用

目的：探究纤维素酶酶法制备稠李花色苷的最佳条件,并研究制备的稠李花色苷对H2O2诱导的大鼠胰岛素瘤（Ins-1）细胞损伤的保护作用。方法：通过单因素试验和正交试验,优化得到酶法制备稠李花色苷的最佳条件;稠李花色苷处理大鼠Ins-1细胞,进行形态学观察、3-（4,5-二甲基噻唑-2）-2,5-二苯基四氮唑溴盐[3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide,MTT]细胞活力实验、2’,7’-二氢二氯荧光素二乙酸酯（2’,7’-dichlorodihydrofluorescein diacetate,DCFH-DA）荧光探针法检测细胞内活性氧实验研究稠李花色苷对H2O2诱导损伤的Ins-1细胞保护作用。结果：纤维素酶法提取稠李花色苷的最佳条件为：温度60 ℃、纤维素酶添加量9 mg/g、料液比1∶35（g/mL）、pH 3.5,此条件下稠李花色苷得率为（0.956±0.027） mg/g;形态学观察及MTT细胞活力实验显示,稠李花色苷对H2O2诱导损伤的Ins-1细胞具有较强的保护作用,DCFH-DA法检测细胞内活性氧实验说明,稠李花色苷能够显著地清除Ins-1细胞内的活性氧。结论：纤维素酶法制备稠李花色苷是一种有效的方法,制备的稠李花色苷对H2O2诱导的大鼠Ins-1细胞损伤具有较强的保护作用。     

越橘提取物中花青素分析及其体外抗氧化活性

研究越橘提取物中花青素的组成与含量及其体外抗氧化活性。实验采用高效液相色谱与质谱联用法对越橘提取物中的花青素组成进行鉴定,并以矢车菊素-3-O-葡萄糖苷为标准品测定了花青素的含量。以V_C为对照,测定越橘提取物对DPPH自由基、ABTS自由基、羟基自由基的清除能力和还原力。结果表明,越橘提取物中含有14种花青素,包括飞燕草素、矢车菊素、矮牵牛素、芍药素和锦葵素类;越橘提取物中花青素的总含量为408.74 μg/mg,其中,矢车菊素类花青素含量最高,为159.93 μg/mg,占总含量的39.12%;体外抗氧化实验表明,越橘提取物的DPPH自由基清除能力、ABTS自由基清除能力和羟基自由基清除能力的IC₅₀分别为26.16、13.07、1.91 mg/mL,还原力在浓度为250 μg/mL时达到0.617。本研究为越橘的开发利用提供一定理论与数据基础。     

黑色小扁豆中不同结合态酚类含量、花青素组成及其抗氧化活性研究

黑色小扁豆因含有丰富的营养素、微量营养素和植物化学物成分而受到研究者的关注。为深入了解小扁豆的营养价值,对小扁豆中不同结合形态的酚类化合物含量及其抗氧化活性(亚铁离子还原能力、DPPH自由基清除能力、ABTS自由基清除能力)进行测定。结果表明,黑色小扁豆中不同存在形式的酚类提取物含量差异显著。酯键合态酚类提取物中含有较高的酚酸含量(1.61 mg/g),碱水解结合态酚类提取物具有较高的黄酮含量(1.07 mg/g)及抗氧化活性【亚铁离子还原能力(43.80 mmol/g)、DPPH自由基清除能力(2.13 mg/g)、ABTS清除能力(3.92 mg/g)】。对黑色小扁豆中存在的花青素进行提取和分析鉴定,其含有的花青素主要为飞燕草-3-O-(2-O-β-D-吡喃葡萄糖基-α-L-吡喃阿拉伯糖苷)和矢车菊素衍生物。     

蔓越莓花色苷的组成鉴定及抗氧化能力

对蔓越莓花色苷的组成进行鉴定,并对其抗氧化能力进行测定。采用pH示差法测定花色苷提取量,超高压辅助提取蔓越莓花色苷含量为（75.49±0.43）mg/100?g,常规溶剂提取蔓越莓花色苷含量为（67.31±1.08）mg/100?g,蔓越莓中总花色苷含量为（79.52±0.50）mg/100?g;选择AB-8大孔树脂对蔓越莓花色苷粗提物进行纯化,冻干粉中花色苷含量从（46.10±0.92）mg/g提高到（309.26±2.37）mg/g。通过测定1,1-二苯基-2-三硝基苯肼自由基清除率、2,2’-联氮基-双-（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基清除能力和总抗氧化能力,比较蔓越莓花色苷与VC的抗氧化能力。结果表明：同质量浓度条件下,蔓越莓花色苷的抗氧化能力强于VC。通过高效液相色谱-质谱联用技术在蔓越莓中鉴定出7?种花色苷：芍药素-3,5-二己糖苷、矢车菊素-3-半乳糖苷、矢车菊素-3-葡萄糖苷、矢车菊素-3-阿拉伯糖苷、芍药素-3-半乳糖苷、芍药素-3-葡萄糖苷、芍药素-3-阿拉伯糖苷,其中芍药素-3,5-二己糖苷首次在蔓越莓中被鉴定出。     

Phenolic Compounds and Bioactivities of Pigmented Rice

The pigmented rice has been consumed in China, Japan, and Korea for a long time. It has been used for strengthening kidney function, treating anemia, promoting blood circulation, removing blood stasis, treating diabetes, and ameliorating sight in traditional Chinese medicine. The extracts from pigmented rice are used as natural food colorants in bread, ice cream, and liquor as well as functional food. The pigmented rice is mainly black, red, and dark purple rice, and contains a variety of flavones, tannin, phenolics, sterols, tocols, γ-oryzanols, amino acids, and essential oils. Anthocyanins are thought as major functional components of pigmented rice. Several anthocyanins have been isolated and identified from the pigmented rice, including cyanidin 3-glucoside, cyanidin 3-galactoside, cyanidin 3-rutinoside, cyanidin 3,5-diglucoside, malvidin 3-galactoside, peonidin 3-glucoside, and pelargonidin 3,5-diglucoside. This review provides up-to-date coverage of pigmented rice in regard to bioactive constituents, extraction and analytical methods, and bioactivities. Special attention is paid to the bioactivities including antioxidant and free radical scavenging, antitumor, antiatherosclerosis, hypoglycemic, and antiallergic activities.     

不同品种紫薯抗氧化物质及体外抗氧化活性比较

为比较福建产区主栽紫薯抗氧化物质成分含量及其体外抗氧化活性,对7个不同品种紫薯中总酚、总黄酮、总花色苷及花青素组分进行了分析,并测定其清除自由基活性。结果表明:福宁紫3号紫薯中所含抗氧化活性成分如总酚、总黄酮、总花色苷和花青素的含量均为最高。通过高效液相色谱法分析测定紫薯中含有的花青素单体主要为飞燕草色素、芍药色素和矢车菊色素,不同品种紫薯中花青素组成及含量表现出的一定的差异性。福宁紫3号紫薯表现出较强的自由基清除活性,0.5 mg·L^-1紫薯鲜样提取液DPPH自由基、OH自由基及ABTS清除率分别达到88.4%、49.1%、90.1%。 相对于其他品种,福宁紫3号紫薯在抗氧化活性成分含量及体外抗氧化活性方面表现最佳。     

Changes of Anthocyanins, Anthocyanidins, and Antioxidant Activity in Bilberry Extract during Dry Heating

ABSTRACT:  Thermal stability of 10 anthocyanins found in a bilberry extract was studied at different heating temperatures and times. Degradation of the 10 anthocyanins, delphinidin, cyanidin, petunidin, peonidin, and malvidin derivatives with different conjugated sugars, followed 1st-order reaction kinetics at heating temperatures 80, 100, and 125 °C. Though the degradation rate constants of anthocyanins were not significantly different from each other at the same heating temperature, they increased drastically when heating temperature was increased to 125 °C. At that temperature, the half-lives for all anthocyanins were less than 8 min. The degradation rate constants followed the Arrhenius equation. The trend of lower activation energy of the anthocyanins with arabinoside than with galactoside or glucoside was observed. These conjugated sugars were cleaved from the anthocyanins to produce their corresponding anthocyanidins or aglycones during heating. The production of anthocyanidins increased constantly and was converted from approximately 30% of the degraded anthocyanins when heated at 100 °C for up to 30 min. At 125 °C, the increase of anthocyanidins lasted for 10 min, after which the degradation rate of anthocyanidins exceeded the production rate. Antioxidant activities of the heated extracts were estimated by measuring DPPH (2, 2'-diphenyl-1-picrylhydrazyl) free radical scavenging activity. The extracts heated at 80 °C for 30 min, 100 °C for 10 and 20 min, and 125 °C for 10 min had higher free radical scavenging capability than unheated extract.     

Antiproliferative effects of cherry juice and wine in Chinese hamster lung fibroblast cells and their phenolic constituents and antioxidant activities

Cherries are good sources of bioactive phenolic compounds that are widely considered to be potentially healthy. Here we investigated the protective activities of juice and wine products of tart and sweet cherries and their constituent anthocyanins (e.g., cyanidin 3-glucoside and cyanidin 3-rutinoside) against oxidative stress induced by hydrogen peroxide (H₂O₂) in Chinese hamster lung fibroblasts (V79-4). Total phenolics in the cherry juices and wines were 56.7–86.8 mg of gallic acid equivalents (GAE)/l and 79.4–149 mg GAE/l, respectively. Total anthocyanins in the cherry juices and wines were 7.9–50.1 mg of cyanidin 3-glucoside equivalents (CGE)/l and 29.6–63.4 mg CGE/l, respectively. Both cherry juices and wines exerted protective effects against oxidative stress induced by H₂O₂ on V79-4 cells and also enhanced the activities of antioxidative enzymes, such as superoxide dismutase and catalase, in a dose-dependent manner. The protection of V79-4 cells from oxidative stress by phenolics was mainly attributable to anthocyanins. The positive correlation between the protective effects against oxidative stress in V79-4 cells and the antioxidant enzyme activities was stronger for cyanidin 3-glucoside than for cyanidin 3-rutinoside.     

Antioxidant activity of corozo (<Emphasis Type="Italic">Bactris guineensis</Emphasis>) fruit by electron paramagnetic resonance (EPR) spectroscopy

The antioxidant activity of an anthocyanin-rich extract (ARE) of corozo fruit (Bactris guineensis) and its major constituents, cyanidin-3-rutinoside, cyanidin 3-glucoside and peonidin-3-rutinoside, was measured by stabilised free-radical EPR spectroscopy. The ARE of corozo exhibited a higher radical scavenging activity than pure anthocyanins using ABTS and DPPH free radicals. The antioxidant activity values for pure anthocyanins against the two radicals were different; however, a second-order kinetic model was followed in all of the cases. A cooperative effect regarding free-radical scavenging activity among studied anthocyanins was suggested. This study is the starting point to consider the ARE of corozo fruit as promising antioxidant material to be used in food industry.     

LC‐MS identification of anthocyanins in boysenberry extract and anthocyanin metabolites in human urine following dosing

The anthocyanin composition of boysenberry (Rubusloganbaccus × baileyanus Britt) extract was determined by LC‐ESI‐MS. Four anthocyanins were identified, all comprising a cyanidin‐anthocyanidin‐type skeleton. The two major components were identified as the disaccharide cyanidin‐3‐O‐sophoroside and the monosaccharide cyanidin‐3‐O‐glucoside. The two less abundant components were identified as the rutinosides, cyanidin‐3‐O‐2^G‐glucosylrutinoside and cyanidin‐3‐O‐rutinoside, respectively. These same four anthocyanins were also detected in human urine following a dosing study with boysenberry extract indicating that glycosylated anthocyanins can be absorbed from the gut and excreted intact in the urine. Several anthocyanin metabolites were also detected in the urine and were identified by LC‐ESI‐MS as monoglucuronides of peonidin, cyanidin and pelargonidin. The results suggest that anthocyanins consumed as part of a diet are bioavailable and are present as intact or metabolized forms in the body. Copyright © 2004 Society of Chemical Industry