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Biological and Chemical Studies on Extracts from Natural Plants and Maillard Reaction Systems.

机译：天然植物和美拉德反应体系提取物的生物化学研究。

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摘要

Medicinal plant extracts that contain antioxidant acitivity have been used to treat various diseases and have received much attention in recent years. The antioxidant activity of volatile extracts of teas prepared from mulberry (Morus alba L.) Camellia sinensis L., Cudrania tricuspidata (Carr.) Burea plant, and broccoli (Brassica oleracea L.) sprouts was examined using three antioxidant assays. All extracts exhibited antioxidant activity with a clear dose response in the aldehyde/carboxylic acid, the malonaldehyde/gas chromatography (MA/GC), 1-1-diphenyl-2-picrylhydrazyl (DPPH) assay. At the level of 500 mug/mL, they inhibited hexanal oxidation by 77.02 +/- 0.51% (stems of Burea plant), 52.57 +/- 0.92% (fermented tea of Camellia and stems of Mulberry tea), and 99.48 +/- 1.49% (broccoli sprouts) in the aldehydes/carboxylic acid assay. MA formation was also inhibited by 76.17 +/- 0.27% (roots of Burea plant) to 59.32 +/- 0.27% (stems of Mulberry tea) at the level of 160 mug/mL, and by 82% (broccoli sprouts) at the level of 500 mug/mL. The antioxidant activity of the extracts obtained from mulberry ( Morus alba L.) Camellia sinensis L., Cudrania tricuspidata (Carr.) Burea plant, and broccoli (Brassica oleracea L.) sprouts was comparable to those of known antioxidants, &agr;-tocopherol and BHT. Volatile extracts were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) to identify the principal antioxidant(s). Among volatile compounds of teas prepared from mulberry (Morus alba L.) Camellia sinensis L., Cudrania tricuspidata (Carr.) Burea plant, eugenol, 2,5-dihydroxyl acetophenone, and isoeugenol exhibited antioxidant activity comparable to that of BHT in both assays. Fraction II of volatile extracts from broccoli sprouts inhibited hexanal oxidation by 96 % for up to 30 days at the level of 100 microg/ml used in the aldehyde/carboxylic acid assay which contained high levels of 4-methylpentylisothiocyanate, 4-methylthiobutylnitrile, 5-methylthiopentylnitrile, 3-methylthiopropylisothiocyanate, and 4-methylthiobutyl-isothiocyanate. The residual aqueous solutions from the steam distillation also exhibited antioxidant activity in the DPPH assay (58% at the level of 1000 mug/ml) and in the lipid/Ma assay (74% at the level of 500 mug/ml).;All Seven fractions obtained from rhubarb were investigated to determine emodin using high-performance liquid chromatography-diode array detection (HPLC-DAD) and then examined for antioxidant activity using MA/GC assays. Among the fractions, fraction VI showed very high antioxidant activity and contains the highest level of emodin. This fraction inhibited MA formation from cod liver oil by 75.4 +/- 13.7% at the level of 50 mug/mL, 92.8 +/- 0.6% at the level of 100 mug/mL, and 93.9 +/- 1.1% at the level of 500 mug/mL. The antioxidant activity of fraction VI was comparable to those of known antioxidants, &agr;-tocopherol and BHT. The positive relationship between emodin and antioxidant activity was observed.;Caramel color is one of the oldest and most widely used colorings for variety of foods and beverages. It is well known that the major reaction that occurs in a caramel model system is Maillard reaction. Amounts of carcinogenic 4(5)-methylimidazole (MI) formed from D-glucose/ammonia /sulfite Mallard model systems were analyzed by LC/MS and GC. The amount formed ranged from 7.0 to 155.0 ppm (LC/MS) and 28.56 to 1,269.71 mug/mL (GC) under various conditions. Addition of sodium sulfide reduced formation of 4(5)-MI significantly, suggesting that sulfite plays an important role in the formation of carcinogenic 4-MI in caramel color. Glyoxal, methylglyoxal, and diacetyl known as precursors of 4(5)-MI formed from sucrose alone and from the D-glucose/ammonia /sulfite Mallard model systems were analyzed by GC. Amounts of glyoxal, methylglyoxal, and diacetyl formed in Maillard model systems ranged from 2.98 to 46.12 mug/mL, from 8.27 to 156.61 mug/mL, and from 14.94 to 1,588.45 mug/mL, respectively. Addition of sodium sulfide also reduced formation of these chemicals significantly. Total &agr;-dicarbonyl compounds in 12 commercial soft drinks ranged from 5.75 to 50.72 mug/mL. 4(5)-MI was found in levels ranging from 1.76 to 28.11 mug/mL in 10 commercial soft drinks.
机译：含有抗氧化剂活性的药用植物提取物已被用于治疗各种疾病，并且近年来受到了广泛的关注。使用三种抗氧化剂测定法检查了从桑树（Morus alba L.）山茶，Cudrania tricuspidata（Carr。）Burea植物和西兰花（Brassica oleracea L.）新芽制备的茶的挥发性提取物的抗氧化活性。所有提取物均在醛/羧酸，丙二醛/气相色谱法（MA / GC），1-1-二苯基-2-吡啶并肼基（DPPH）分析中表现出明显的抗氧化剂活性。在500杯/毫升的水平上，它们抑制己醛氧化的程度分别为77.02 +/- 0.51％（Burea植物的茎），52.57 +/- 0.92％（山茶的发酵茶和桑树茶的茎）和99.48 +/-。在醛/羧酸测定中为1.49％（西兰花芽）。在160杯/毫升的水平下，MA的形成也被76.17 +/- 0.27％（Burea植物的根）抑制为59.32 +/- 0.27％（桑树茶的干）; 500杯/毫升的水平。从桑树（Morus alba L.）茶花，Cudrania tricuspidata（Carr。）Burea植物和西兰花（Brassica oleracea L.）芽中获得的提取物的抗氧化活性与已知的抗氧化剂α-生育酚相当。和BHT。挥发性提取物通过气相色谱（GC）和气相色谱-质谱（GC / MS）进行分析，以鉴定主要抗氧化剂。在两种测定中，由桑树（Morus alba L.）山茶、,木（Cudrania tricuspidata）（Carr。Burea）植物制得的茶的挥发性化合物中，丁香酚，2,5-二羟基苯乙酮和异丁香酚的抗氧化活性均与BHT相当。 。西兰花芽的挥发物提取物的馏分II在醛/羧酸测定中使用的100微克/毫升的水平上将96％的己醛氧化抑制长达30天，该醛/羧酸测定中含有高含量的4-甲基戊基异硫氰酸酯，4-甲基硫代丁基腈，5-甲硫基戊腈，3-甲硫基丙基异硫氰酸酯和4-甲硫基丁基异硫氰酸酯。来自蒸汽蒸馏的残留水溶液在DPPH分析中（1000杯/毫升的水平为58％）和脂质/ Ma分析（500杯/毫升的水平74％）也显示出抗氧化活性。使用高效液相色谱-二极管阵列检测（HPLC-DAD）对大黄中的七种馏分进行了研究，以确定大黄素，然后使用MA / GC分析检测了抗氧化活性。在馏分中，馏分VI显示出非常高的抗氧化活性，并且含有最高水平的大黄素。该组分在50杯/毫升的水平下抑制了从鱼肝油中形成MA的75.4 +/- 13.7％，在100杯/ mL的水平下抑制了92.8 +/- 0.6％和93.9 +/- 1.1％的水平500杯/毫升。馏分VI的抗氧化活性与已知的抗氧化剂α-生育酚和BHT相当。观察到大黄素与抗氧化活性之间呈正相关关系。焦糖色是最古老，使用最广泛的多种食品和饮料色料之一。众所周知，在焦糖模型系统中发生的主要反应是美拉德反应。通过LC / MS和GC分析了由D-葡萄糖/氨水/亚硫酸盐Mallard模型系统形成的致癌4（5）-甲基咪唑（MI）量。在各种条件下，形成的量为7.0至155.0 ppm（LC / MS）和28.56至1,269.71杯/ mL（GC）。硫化钠的添加显着减少了4（5）-MI的形成，表明亚硫酸盐在焦糖色的致癌性4-MI的形成中起着重要作用。通过GC分析了由单独的蔗糖和由D-葡萄糖/氨/亚硫酸盐Mallard模型系统形成的4（5）-MI的前体的乙二醛，甲基乙二醛和二乙酰基。在Maillard模型系统中形成的乙二醛，甲基乙二醛和二乙酰基的量分别为2.98至46.12马克杯/毫升，8.27至156.61马克杯/毫升和14.94至1,588.45马克杯/毫升。硫化钠的添加也显着减少了这些化学物质的形成。 12种商业软饮料中的-二羰基化合物总量为5.75至50.72杯/毫升。在10种商业软饮料中发现的4（5）-MI含量范围为1.76至28.11马克杯/毫升。

著录项

  • 作者

    Jang, Hae Won.;

  • 作者单位

    University of California, Davis.;

  • 授予单位 University of California, Davis.;
  • 学科 Agriculture Food Science and Technology.;Chemistry Analytical.
  • 学位 Ph.D.
  • 年度 2013
  • 页码 127 p.
  • 总页数 127
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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