乔麦精粉中的黄酮及其自由基清除活性

对５种不同来源的荞麦Ａｓｔｒａ,Ｈｒｕｓｚｏｗｓｋａ,Ｌｅ Ｈａｒｐｅ Ｌｉｌｅｊａ及Ｐｒｅｇｏ的黄酮物质进行了研究。光谱分析表明Ａｓｔｒａ、Ｈｒｕｓｚｏｗｓｋａ,Ｌｅ Ｈａｒｐｅ、Ｌｉｌｅｊａ和Ｐｒｅｇｏ精粉中总的抗氧化剂含量分别为１４．６、２１．４、１３．８、１６．０和１１．４ｍｇ／１００ｇ;反相高效液相色谱分析说明,除了荞麦中最重要的芦丁以外,Ａｓｔｒａ中有白藜芦醇,原儿茶酸和儿茶素,Ｈｒｕ     

苦荞提取液的抗氧化活性研究

本文研究了苦荞籽粒各部分提取液的抗氧化活性 ,抗氧化能力大小顺序为麸皮 >外层粉 >芦丁>壳 >心粉。提取液中的总酚含量在 2 .34～ 4 3.4 5mgGAE/ 10 0mL ,酚酸主要是原儿茶酸和对羟基苯甲酸 ,黄酮浓度在 4 .34～ 74 .35mg芦丁 / 10 0mL ,原花色素浓度在 0 .6～ 10 0 .6mg/ 10 0mL。提取液的抗氧化活性是总多酚共同作用的结果     

毛细管电泳-电化学检测测定荞麦中表儿茶素、芦丁、槲皮素的含量

用毛细管电泳-电化学检测的方法研究了荞麦中黄酮类物质:表儿茶素、芦丁、槲皮素的含量,研究了电极电位、缓冲液的pH值、分离电压及进样时间对电泳的影响,得到优化的测定条件。以直径为300μm的碳圆盘电极为检测电极,工作电极电位为0.95V(vs.SCE),在50mmol/L硼砂(pH8.5)运行缓冲液中,上述3组分在12min内完全分离。表儿茶素、芦丁、槲皮素线性范围分别为5×10-7￣1×10-4g/mL、1×10-6￣1×10-4g/mL、1×10-6￣1×10-4g/mL;检出限分别为1.83×10-7g/mL、2.9×10-8g/mL、1.00×10-7g/mL;3种标样7次平行进样的相对标准偏差(RSD)小于2.5%;回收率表儿茶素100.4%、芦丁98.1%、槲皮素100.1%(n=3)。该法灵敏可靠,结果令人满意。     

苦荞饮料黄酮、酚酸含量及抗氧化能力分析

本文探究了苦荞饮料制作过程中及苦荞饮料与市售饮品之间总黄酮、总酚酸含量及抗氧化能力的差异。分别采用三氯化铝比色法、福林酚法测定饮料中总黄酮和总酚酸的含量,运用高效液相色谱质谱联用仪测定自制苦荞饮料及市售饮品中单体黄酮酚酸含量并进行对比,并对1,1-二苯基-2-苦基肼自由基清除能力和2,2’-联氮-双(3-乙基-苯并噻唑啉-6-磺酸)二铵盐自由基清除能力进行分析。结果表明:苦荞饮料的总黄酮含量为0.1258mg/g、总酚酸含量为0.2767μg/g、清除1,1-二苯基-2-苦基肼自由基能力半抑制浓度值为70.79mg/mL、清除2,2’-联氮-双(3-乙基-苯并噻唑啉-6-磺酸)二铵盐自由基能力半抑制浓度值为57.49mg/mL,苦荞饮料中表儿茶素、儿茶素、槲皮素、芦丁、原儿茶酸含量分别为48.52、133.30、374.00、464.70、666.00μg/g。苦荞饮料中表儿茶素、儿茶素、槲皮素、芦丁、原儿茶酸含量,均高于四种市售饮品,所以苦荞饮料可以作为一种特色饮料走向市场。     

‘菲尔杜德’和‘托拉蜜’红树莓果实发育过程中5种酚类物质含量的研究

目的 阐明‘菲尔杜德’和‘托拉蜜’红树莓不同发育时期果实的5种酚类物质含量的研究。方法 采用高效液相色谱法,选择C18色谱柱（200 mm*4.6 mm,5 μm）,以乙腈和0.5% 乙酸水溶液为流动相进行梯度洗脱,对两品种红树莓4个发育时期果实（青果、黄果、红果、深红果）中咖啡酸、阿魏酸、儿茶素、表儿茶素和芦丁的含量进行分析测定;检测波长为280 nm,流速为0.8 mL/min,柱温为25 ℃。结果 红树莓从青果发育到深红果的过程中,‘菲尔杜德’和‘托拉蜜’ 的咖啡酸含量均呈先下降后上升的趋势,深红果的咖啡酸含量最高,最高值分别为16.383 mg/100 g FW、60.815 mg/100 g FW,‘托拉蜜’深红果的咖啡酸含量极显著高于‘菲尔杜德’（P＜0.01）;两品种的阿魏酸含量、儿茶素含量、表儿茶素含量、芦丁含量均呈下降趋势,均为青果的含量最高,阿魏酸最高含量分别为163.752 mg/100 g FW和143.148 mg/100 g FW,儿茶素最高含量分别为543.915 mg/100 g FW 和139.058 mg/100 g FW,表儿茶素最高含量分别为2.079 mg/100 g FW和1.603 mg/100 g FW,芦丁最高含量分别为0.906 mg/100 g FW和0.651 mg/100 g FW。‘菲尔杜德’青果的阿魏酸、儿茶素、表儿茶素、芦丁含量极显著高于‘托拉蜜’青果（P＜0.01）。结论 在‘菲尔杜德’和‘托拉蜜’红树莓果实发育过程中,5种酚类物质的含量变化规律在两品种间一致,采摘‘菲尔杜德’青果时期的果实可得到最高含量的阿魏酸、儿茶素、表儿茶素、芦丁,采摘 ‘托拉蜜’深红果时期的果实可得到最高含量的咖啡酸。本研究为更好的利用其酚类物质研发营养保健食品及药物提供了重要的理论依据。     

山楂多酚含量的反相高效液相色谱法测定

建立同时测定山楂中绿原酸、表儿茶素和芦丁3 种酚类物质的反相高效液相色谱方法,并研究这三种酚类物质在山楂干果果肉、干果果核和鲜果果肉中的含量。经测定,表儿茶素在山楂鲜果果肉中含量最高,达到(1.661 ± 0.024) mg/g;绿原酸和芦丁在山楂干果果肉中含量最高,分别达到(0.550 ± 0.002) mg/g 和(0.498 ± 0.002) mg/g。本方法样品处理简单,具有良好的重现性和线性,相关性系数均达到0.999,绿原酸、表儿茶素和芦丁的回收率分别为91.8%～110.9%、94.6%～107.9% 和94.2%～108.8%;检出限分别为0.14、0.37 和0.68μg/ml (S/N ＝ 3)。     

木瓜酒发酵过程中多酚类物质的高效液相色谱测定及含量变化分析

实验优化了高效液相色谱法同时测定木瓜酒中10种多酚类物质的测定条件,并分析各单体酚在发酵过程中的含量变化情况。结果表明,在优化的色谱条件下,木瓜酒中10种多酚物质能在60 min之内得到有效分离,各酚类物质在0.1~10 mg/L的质量浓度范围内相关系数R~20.993 6,线性关系良好,检出限在0.01~0.02mg/L之间,木瓜酒样品加标回收率在97.04%~107.32%之间,回收率高、准确可靠,适用于同时测定木瓜酒中没食子酸、原儿茶酸、香豆酸、绿原酸、槲皮苷、咖啡酸、儿茶素、芦丁、表儿茶素、山奈素10种酚类物质。经测定,3种木瓜酒中各单体酚含量在发酵过程中变化趋势与总酚含量基本一致,呈现先增加而后缓慢减少的趋势,发酵4个月后,3种木瓜酒中总多酚含量均显著增加(p0.05)。野木瓜酒(样品1)、皱皮木瓜酒(样品2)和光皮木瓜酒(样品3)的总多酚含量分别为903、1 178、1 057 mg/100 m L。3种木瓜酒中各酚类物质在发酵过程中变化趋势与总酚含量基本一致,主要含有的多酚物质有儿茶素、原儿茶酸和绿原酸;儿茶素含量在3种木瓜酒中含量最高且差异显著(p0.05),可用于区分上述3种木瓜品种。     

提取工艺对色谱法检测芦荟叶多酚含量影响

试验采用高效液相色谱法法比较不同提取工艺对芦荟叶中没食子酸(Gallic acid)、原儿茶酸(Protocate-chuicacid)、儿茶素(Catechin)、绿原酸(Chlorogenicacid)、表儿茶素(Catechin)、咖啡酸(Caffeicacid)、阿魏酸(Ferulicacid)和芦丁(Rutin)8种多酚含量的影响。试验采用ZORBAX SB-C18色谱柱(125 mm×4.6 mm×5μm),流动相A相为乙腈;流动相B相为0.1(V/V)甲酸,梯度洗脱,流速为0.8 mL/min,DAD检测波长为280 nm,柱温为45℃。检测结果表明,不同提取工艺得到的芦荟叶粉中没食子酸、原儿茶酸、儿茶素、绿原酸、表儿茶素、咖啡酸、阿魏酸和芦丁8种芦荟叶多酚的总含量以超临界二氧化碳萃取最高,超临界二氧化碳萃取过程没有加热处理,最大程度地保留了芦荟叶多酚;该检测方法在加标为1 000~100 000μg/kg浓度范围内的回收率为98.21%~103.28%,精密度为1.29%~4.67%(n=6),方法的检出限为0.02~0.05 mg/L,检测线性范围最宽为0.01~500 mg/kg;结果表明,从芦荟叶多酚的含量及物质特性保留的角度考虑,选择芦荟叶的提取工艺以超临界二氧化碳萃取为宜。     

萌发荞麦中芦丁和槲皮素含量变化的研究

研究分析荞麦萌发过程中芦丁和槲皮素含量的变化趋势,为荞麦萌动食品的开发提供了理论参考。以发芽时间为试验因素,采用反相液相色谱法对荞麦萌发前后的芦丁和槲皮素进行测定比较。结果表明(1)萌发有助于提高苦荞中芦丁和槲皮素的含量,有助于提高甜荞中芦丁的含量。苦荞萌发7 d后芦丁含量为19.33 mg/g远高于甜荞的0.66 mg/g。(2)苦荞萌发过程中芦丁含量呈先上升后下降再上升的趋势,萌发7 d后芦丁含量提高了66.64%。甜荞萌发7 d后,芦丁含量提高了75.13%。苦荞萌发7 d,槲皮素含量整体呈上升趋势,由8.93 mg/g上升至11.90 mg/g。甜荞萌发过程中未检测出槲皮素。荞麦萌动后提高了黄酮类成分,苦荞中的芦丁含量萌发前后均高于甜荞,选择苦荞作为荞麦萌动食品原料具有更好的营养价值。     

不同等级荞麦粉抗氧化性研究

以中国固阳荞麦和加拿大温莎荞麦籽粒为材料,采用石磨法磨制荞麦粉,以出粉率不同收集全粉(90%)、普粉(75%)、精粉(60%)和营养粉(40%)4个等级粉,采用甲醇提取荞麦粉抗氧化物质,分析其抗氧化活性。结果表明,荞麦营养粉的总酚、总黄酮含量最高,精粉最低。固阳荞麦营养粉的总酚和总黄酮含量分别为(3.80±0.05)和(5.49±0.20)mg/g,加拿大温莎荞麦营养粉的总酚和总黄酮含量分别为(4.10±0.09)、(5.45±0.05)mg/g。荞麦营养粉的总抗氧化能力显著高于全粉,全粉显著高于精粉。荞麦各等级粉对DPPH·、·OH及ABTS+·均具有一定的清除能力,清除作用大小为营养粉全粉普粉精粉。固阳荞麦营养粉具有更高的亚铁离子螯合能力,加拿大温莎营养粉和全粉的亚铁离子螯合能力显著高于普粉和精粉。荞麦粉总抗氧化能力、DPPH·清除率、·OH清除率、ABTS+·清除率、亚铁离子螯合能力与总酚、总黄酮含量呈高度正相关。     

荞麦蜜酚酸含量的高效液相色谱测定及其抗氧化作用的研究

以中国产荞麦蜜为原料,采用高效液相色谱-电化学检测法(HPLC-ECD)测定其中的原儿茶酸、没食子酸、咖啡酸、丁香酸、p-香豆酸、绿原酸、阿魏酸和鞣花酸等8种酚酸的含量。结果表明,中国荞麦蜜中含有原儿茶酸、没食子酸、咖啡酸、p-香豆酸、阿魏酸等五种酚酸,其含量分别为没食子酸为461μg/100g蜂蜜,p-香豆酸为150μg/100g蜂蜜,咖啡酸为79μg/100g蜂蜜,原儿茶酸为30μg/100g蜂蜜,阿魏酸为39μg/100g蜂蜜。本文还对荞麦蜜酚酸提取物的抗氧化作用进行了研究,结果显示荞麦蜜酚酸提取物对超氧阴离子自由基、羟基自由基、DPPH自由基和脂质过氧化均有抑制作用。     

云南水晶石榴果皮中多酚组分及抗氧化活性分析

对云南水晶石榴果皮中的多酚含量和组成进行了分析,并研究了其提取物的抗氧化活性。结果表明:云南水晶石榴果皮中多酚含量为99.60 mg/g(干重);香豆酸、儿茶素和原儿茶酸是多酚的主要成分,含量分别为4.80、3.96和1.96 mg/g(干重)。多酚提取物的还原能力、DPPH自由基清除能力、抑制脂质体过氧化能力和清除亚硝酸盐能力较强,且与浓度显著性正相关(P<0.01),相关性系数(R2)在0.888 1～0.995 8。     

Fractionation and quantification of phenolic antioxidants from Saeunamu (Ostrya japonica)

Saeunamu (Ostrya japonica), a natural plant in Jeju, was extracted and fractionated on a Sephadex LH-20 column, and their phenolic compounds and integral antioxidative capacity (IAC) were evaluated. Eight fractions were obtained, and the relative contents of ethanol fractions (F1-F6) and methanol fractions (F7, F8) were 64.0 and 33.1%, respectively. Total phenolics in the methanol fractions were high as 672.8 and 613.3 mg catechin equivalents (CE)/g in F8 and F7, compared with those in the ethanol fractions as 438.4 and 411.1 mg CE/g in F4 and F5, respectively. Only 4 phenolics such as protocatechuic acid, caffeic acid, catechin, and quercetin were identified. Catechin was concentrated as 4.6 and 4.4 times in F7 and F8, and quercetin was 2.9 and 2.6 times in F5 and F6, respectively, compared with the unfractionated. IAC of water-soluble substances were high as 6.41 and 7.71 mmol ascorbic acid equivalents/g, and those of lipid-soluble substances were high as 2.50 and 2.41 mmol Trolox equivalents/g in F4 and F5, respectively. It was concluded that ethanol fractions (F4-F6) possessing strong IAC may be used as a natural source of antioxidants in functional food ingredients.     

Major Polyphenolics in Pineapple Peels and their Antioxidant Interactions

Major polyphenolic compounds in pineapple peels were identified and quantified. The antioxidant capacities of pineapple peel extracts and these polyphenolic compounds were determined using DPPH? scavenging capacity and phosphomolybdenum method. Effects of these polyphenolics’ interactions on their antioxidant capacity were also evaluated. Gallic acid (31.76 mg/100 g dry extracts), catechin (58.51 mg/100 g), epicatechin (50.00 mg/100 g), and ferulic acid (19.50 mg/100 g) were found to be the main polyphenolics in pineapple peels. The IC₅₀ for DPPH? scavenging assay of the extracts was 1.13 mg/ml and total antioxidant capacity was 0.037 g ascorbic acid equivalents/g. The order of DPPH? scavenging capacity of per mole of these polyphenolic compounds present in pineapple peels was gallic acid > epicatechin = catechin > ferulic acid, but it was different when using phosphomolybdenum method the order of which was epicatechin. > catechin > gallic acid = ferulic acid. Results of polyphenolics’ interactions indicated no synergistic effects. In the combinations of ferulic acid-epicatechin and ferulic acid-gallic acid, additive effects were found using both antioxidant activity assays.     

Major flavan-3-ol composition and antioxidant activity of seeds from different grape cultivars grown in Turkey

The major flavan-3-ols composition and antioxidant activity of the seeds of 12 different common grape varieties that grow in Turkey were investigated. The quantities of gallic acid, catechin, epicatechin and total flavan-3-ol were determined with high performance liquid chromatography (HPLC) and spectrophotometric method in grape seeds extracts. Gallic acid, catechin, epicatechin and total flavan-3-ol varied from 18 to 101, 121–845, 85–893 and 4 507–13 360 mg/100 g in grape seeds, respectively. The seeds of Papaz Karası, Alicante Boushet and Kalecik Karası cultivars were good sources for these compounds among the cultivars examined. In most cultivars, the amount of epicatechin was greater than that of catechin. The cultivars that have high total flavan-3-ol content had the strongest free radical scavenging activities and results were shown that there is a highly significant correlation between the total flavan-3-ol content and antiradical efficiency (AE) (r=0.9168, P<0001).     

UPLC-DAD/ESI-TOF-MS鉴定黑脉羊肚菌多酚化合物

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。     

Fatty acid composition,oxidative stability,antioxidant and antiproliferative properties of selected cold-pressed grape seed oils and flours

Cold-pressed chardonnay, muscadine, ruby red, and concord grape seed oils and their defatted flours were studied for their fatty acid composition, oxidative stability and antioxidant and antiproliferative activities. The phenolic profiles of the seed flours were also measured. The most abundant fatty acid in the oils was linoleic acid, ranging from 66.0 g/100 g of total fatty acids in ruby red seed oil to 75.3 g/100 g of total fatty acids in concord seed oil. The oils were also high in oleic acid and low in saturated fat. Ruby red grape seed oil recorded the highest oxidative stability index of 40 h under the accelerated conditions. Total phenolic content (TPC) was up to 100 times lower in the oils than in the flours. Lutein, zeaxanthin, cryptoxanthin, β-carotene, and α-tocopherol levels were also measured. DPPH radical-scavenging capacity ranged from 0.07 to 2.22 mmol trolox equivalents (TE)/g of oil and 11.8 to 15.0 mmol TE/g of flour. Oxidative stability of menhaden fish oil containing extracts of the seed flours was extended by up to 137%. HPLC analysis was conducted to determine the levels of free soluble, soluble conjugated and insoluble bound phenolics in the seed flours. The phenolic compounds analyzed included catechin, epicatechin, epicatechin gallate, quercetin, gallic acid, and procyanidins B1 and B2. Antiproliferative activity was tested against HT-29 colon cancer cells. All of the seed flours and muscadine seed oil registered significant (P < 0.05) inhibition of cancer cell growth. The results from this study demonstrate the potential of developing value-added uses for these seed oils and flours as dietary sources of natural antioxidants and antiproliferative agents for optimal health.     

Determination of folate in some cereals and commercial cereal-grain products consumed in Poland using trienzyme extraction and high-performance liquid chromatography methods

A trienzyme treatment (rat plasma conjugase, -amylase, protease) followed by affinity chromatography (with folate-binding protein from bovine milk) and reversed-phase high-performance liquid chromatography with UV and fluorescence detections was performed for quantification of different folate derivatives in some commercial cereal-grain products and cereals cultivated in Poland. The method described allowed good separation of the main folate vitamins. Of the commercial cereal-grain products analyzed, buckwheat groats (30 g/100 g) had the highest content of total folate, followed by rye flour (29 g/100 g), barley groats (21 g/100 g) and wheat flours (19–20 g/100 g). Two of the ready-to eat breakfast products were found to be fortified with folic acid with the level slightly exceeding the label declaration. The total folate content of whole-grain wheat flours was more than half as much as in white flours (33–40 g/100 g), and the highest folate content was found in rye whole grains (123–135 g/100 g). 5-Formyltetrahydrofolate was the predominating folate form in the cereal products analyzed, above all in rye flour.     

The antioxidant activity and the bioactive compound content of Stevia rebaudiana water extracts

Stevia rebaudiana (SR), a chrysanthemum herb, has been used as a vegetable-based sweetening additive in health drinks and in other foods. This study was conducted to investigate the antioxidant activity and the bioactive compounds found in water extracts taken from SR leaves and calli. Analysis of vitamins in the leaves showed that folic acid (52.18 mg/100 g) was a major component, followed by vitamin C. The total phenolic and flavonoid contents were found to be 130.76 μg catechin and 15.64 μg quercetin for leaves and 43.99 μg catechin and 1.57 μg quercetin for cellus at mg of water extracts, respectively. Pyrogallol was the major material among the phenolic compounds in both leaf and callus extracts. Furthermore, our results showed that the leaf extracts contained higher amounts of free radicals, hydroxyl radicals and superoxide anion radical scavenging activities than those of the callus extracts.