【作者】 吕俊丽；

【导师】 刘邻渭； 俞良莉；

【作者基本信息】 西北农林科技大学 ， 粮食、油脂及植物蛋白质工程， 2013， 博士

【摘要】 小麦(Triticum aestivum L.)是我国三大主粮之一，从营养价值和加工性能方面，小麦是世界上公认的最具加工优势的谷类作物。由小麦制作的食品几乎是所有发达国家餐桌主食的核心，同时也是其农业的主要支柱。由小麦磨制的小麦粉在人们的日常饮食中占据举足轻重的地位，因此对小麦粉的研究意义重大。目前对小麦粉研究较多的主要集中于蛋白质数量、质量、淀粉品质等与面包、面条、馒头加工品质及育种之间的关系，而对小麦粉的营养品质、抗氧化特性及抗癌功能方面的研究甚少。美国是生产小麦的大国，也是世界小麦第一出口国。因此，对美国小麦品质的研究意义重大。本文以美国马里兰州气候条件不同的4个地区的10个小麦品种为原料，磨制小麦粉，出粉率为77.8%~83.0%，对小麦粉中的类胡萝卜素、维生素E、酚酸等功能营养素的含量及抗氧化特性进行研究，并分析了小麦品种、生长环境及品种×环境互作对其影响程度，同时对小麦粉抗癌细胞增殖能力进行了初步研究，取得以下主要结果：（1）小麦粉中的酚酸以三种形式存在，即游离态、共价键结合态和不溶性束缚型。总酚酸主要以阿魏酸、对香豆酸、香草酸、丁香酸、咖啡酸5种酚酸组成，其含量依次为：阿魏酸>对香豆酸>香草酸>丁香酸>咖啡酸。其中阿魏酸主要以不溶性束缚酸的形式存在，含量为123.36~373.95μg/g，占总阿魏酸含量的89.74~94.29%。（2）小麦粉中类胡萝卜素主要包括叶黄素和玉米黄素。其中叶黄素是主要的类胡萝卜素，含量为0.27~0.46μg/g，玉米黄素含量为0.08~0.13μg/g。小麦粉中的生育酚主要包括α-和δ-生育酚，α-生育酚是主要的生育酚，含量为0.30~0.59μg/g，δ-生育酚含量为0.07~0.29μg/g。（3）小麦粉中总酚含量为1.66~2.00mg GAE/g，该类物质具有较强的清除自由基的能力。其二苯代苦味酰基自由基(DPPH·)清除能力约为0.72~1.07μmol TE/g，氧自由基吸收能力为29.90~40.20μmol TE/g，羟自由基清除能力为31.22~41.55μmol TE/g，清除ABTS·+自由基能力为2.01~2.48μmol TE/g。（4）总酚含量与清除ABTS+、 HO、DPPH能力及氧自由基吸收能力等均存在显著正相关性（p <0.001），表明总酚含量对小麦粉的抗氧化能力起着重要的作用。同时，ABTS·+清除能力与DPPH·和氧自由基吸收能力之间呈极显著正相关（p <0.01）。（5）小麦的生长环境对面粉中的类胡萝卜素、总酚、阿魏酸含量有重要影响，也是影响自由基清除能力的主要因素，而生育酚、香草酸、咖啡酸和丁香酸含量主要受品种×环境互作的影响。（6）小麦从抽穗到完熟期间，最高气温、平均气温对小麦粉清除DPPH、ABTS·+自由基和氧自由基吸收能力影响较大，而降水量对其影响较小。（7）小麦品种Jamestown (Keedysville)对HT-29和Caco-2细胞增殖具有明显的抑制作用，而SS MPV57(Clarksville)和USG3555(Keedysville)具有较强的抑制HT-29细胞增殖的作用，对Caco-2细胞增殖的抑制作用不明显。更多还原

【Abstract】 Wheat (Triticum aestivum L.) is one of the three major staple foods in China, and it isrecognized as the best cereal.both from the nutritional value and processing performance inthe world. Wheat product is not only the core of staple food in developed countries, but alsothe main pillar of its agriculture. Flour, made from milling wheat, plays a pivotal role in thediet of people’s daily life. Therefore, it is significant to make some research on flour. Atpresent, more research on flour were focused on the relationship between protein quantity,quality, starch quality and bread, noodle, steamed bread and breeding, but there is littlereference reported on the nutritional quality, antioxidant and anti-cancer activities of wheatflour.The United States is a great nation in the production of wheat, but also the first wheatexporter in the world. Thus, it is very important to make a research on the wheat in US. Using40(10wheat varieties×4growing environment) of the Maryland-grown soft wheat flour asexperimental material, the carotenoids, vitamin E, phenolic acids and antioxidant properties inthe flour were studied. This study also analyzed the impacts of wheat genes, environment andtheir interactive effects on the phytochemical compositions and antioxidant activities.Meanwhile, anti-proliferation abilities of wheat flour were also preliminary discussed. Themain results were exhibited as follows:(1) Phenolic acids in wheat flour were soluble free, soluble conjugated and insoluble boundphenolic acid. According to the contents of total phenolic acids in flour, the order of majorfive phenolic acids in wheat flour was as follows: ferulic acid> p-coumaric acid> vanillicacid> syringic acid> caffeic acid. Insoluble bound ferulic acid was the predominant phenolicacid, and its content was123.36~373.95μg/g, which contributed89.74~94.29%of the totalferulic acid on a per wheat flour weight basis in this study.(2) The carotenoids in tested flour included lutein and zeaxanthin. Lutein, the maincarotenoids, was0.27~0.46μg/g, and the zeaxanthin content was0.08~0.13μg/g.Tocopherol mainly consisted of α-tocopherol and δ-tocopherol. α-Tocopherol was the main tocopherol, and its content was in the range of0.30~0.59μg/g, while δ-tocopherol contentwas0.07~0.29μg/g.(3) Total phenolic contents of tested flour were in the range of1.66~2.00mg GAE/g inthis study, and had strong scavenging free radicals abilities. The DPPH free radicalscavenging capacity was0.72~1.07μmol TE/g. Oxygen radical absorbing capacity was29.90~40.20μmol TE/g. Hydroxyl radical scavenging ability was31.22~41.55μmol TE/g.ABTS+removal capacity was2.01~2.48μmol TE/g.(4) Total phenolic content was significantly positive correlated with scavenging abilitiesof ABTS+, DPPH, hydroxyl and oxygen radicals (p <0.001), suggesting total phenoliccontent plays an important role in the antioxidant ability of flour. Besides, ABTS+, DPPH andoxygen radical scavenging abilities were also significantly positive correlated (p <0.01).(5) Carotenoids, total phenolic, ferulic acid and free radical scavenging abilities weremainly affected by growing environment. Whereas, the contents of tocopherols, vanillic acid,caffeic acid and syringic acid were mainly controlled by the interaction between genes andenvironment.(6) During heading to mature period, the DPPH, ABTS+and oxygen radical scavengingabilities of wheat were mainly affected by maximum temperature and the overall averagetemperature, while rainfall played much less influence on them in the current study.(7) Jamestown (Keedysville) wheat flour showed significant antiproliferative activitiesagainst both HT-29and Caco-2colon cancer cells. SS MPV57(Clarksville) and USG3555(Keedysville) showed strong inhibitive effects just in HT-29cancer cells, and itsantiproliferative activity on Caco-2cells was not obvious.更多还原