荞麦手性肌醇提取及其降糖功能研究

该文报道Gr+3催导苦荞(Fagopyrium tartarian)仁发芽,整粒抽提种子中手性肌醇(D-chiro- inositol,D-CI)工艺方法;并使用SPSS软件评价D-CI抽提物对糖尿病ICR小鼠具有显著降低空 腹血糖(FBG)(P<0．05),及对糖尿病患者具有显著降低空腹血糖(FBG)和极显著降低餐后血糖 (PG)作用(P<0．01)。     

Buckwheat trypsin inhibitor enters Hep G2 cells by clathrin-dependent endocytosis

Recombinant buckwheat trypsin inhibitor (rBTI) was studied to evaluate if it could enter cancer cells and to determine the mechanism. Fluorescein isothiocyanate-labelled buckwheat trypsin inhibitor (FITC-BTI) entered Hep G2 cells in a concentration-dependent manner. FITC-BTI colocalised with labelled transferrin (Tf) in the punctate structure, implying that rBTI enters Hep G2 cells by clathrin-dependent endocytosis. Incubation of Hep G2 cells with different chemical inhibitors abolished diffuse, but not punctate fluorescence, thus indicating that membrane potential plays a critical role in this process. Impairment of clathrin-mediated endocytosis by RNAi with clathrin heavy chain greatly reduced or completely abolished both diffuse and punctate fluorescence, further supporting a theory of a single route of endocytosis. Consistent with our working hypothesis, Hep G2 cells which were arrested in the M phase did not show any vesicular or diffuse FITC-BTI. We conclude from these results that both endocytosis and membrane potential are required for rBTI entry into Hep G2 cells.     

Impact of Rutin and Other Phenolic Substances on the Digestibility of Buckwheat Grain Metabolites

Tartary buckwheat (Fagopyrum tataricum Gaertn.) is grown in eastern and central Asia (the Himalayan regions of China, Nepal, Bhutan and India) and in central and eastern Europe (Luxemburg, Germany, Slovenia and Bosnia and Herzegovina). It is known for its high concentration of rutin and other phenolic metabolites. Besides the grain, the other aboveground parts of Tartary buckwheat contain rutin as well. After the mixing of the milled buckwheat products with water, the flavonoid quercetin is obtained in the flour–water mixture, a result of rutin degradation by rutinosidase. Heating by hot water or steam inactivates the rutin-degrading enzymes in buckwheat flour and dough. The low buckwheat protein digestibility is due to the high content of phenolic substances. Phenolic compounds have low absorption after food intake, so, after ingestion, they remain for some time in the gastrointestinal tract. They can act in an inhibitory manner on enzymes, degrading proteins and other food constituents. In common and Tartary buckwheat, the rutin and quercetin complexation with protein and starch molecules has an impact on the in vitro digestibility and the appearance of resistant starch and slowly digestible proteins. Slowly digestible starch and proteins are important for the functional and health-promoting properties of buckwheat products.     

Antioxidant properties of tartary buckwheat extracts as affected by different thermal processing methods

The effects of roasting, pressured-steam heating and microwave heating on total phenolics, total flavonoids, and antioxidant properties of whole-meal flour from tartary buckwheat (Fagopyrum tataricum Gaertn.) were investigated. The total phenolics were evaluated by Folin-Ciocalteau assay, total flavonoids by aluminum nitrate colorimetric assay whilst antioxidant properties were based on free radical scavenging activity of flour extracts against hydroxyl and superoxide anion radicals, and inhibition of lipid peroxidation in vitro. This study showed that thermal treatment of buckwheat flour caused a decrease in total phenolics, total flavonoids and antioxidative activities. The changes in trend of the antioxidant activities due to the thermal treatment were positively correlated with the content of phenolics (R² = 0.8401-0.9909). Therefore, it can be suggested that special care should be taken when processing method is selected for the exploration of tartary buckwheat products.     

苦荞遗传多样性分析与核心种质筛选--测试文章

利用SSR分子标记技术,对来自西藏、陕西、四川、贵州等4省区的210份苦荞品种进行遗传多样性研究。结果表明,所选用的50对SSR引物中,有16对引物多态性良好,共扩增出178个条带,其中多态性条带达118个,占总数的66.3%;210份苦荞种质的遗传变幅为0.62～0.98,平均值为0.80,在遗传相似系数为0.88处可划分为5大类。聚类结果显示,来自同一地区的苦荞品种显示出聚为一类的趋势,表明苦荞的遗传信息受地理分布的影响较大;第V类所聚的41份分别来自西藏（27份）、陕西（8份）和贵州（6份）的品种表现出较为丰富的遗传多样性,与其他种质相比,这41份材料不仅遗传差异较大,而且遗传来源广泛,可作为苦荞核心种质筛选的基础。     

苦荞麦麸复合饮料的研究

为综合开发苦荞功能食品,以苦荞麦麸为主要原料,对苦荞麦麸复合饮料的工艺进行研究。结果表明:过40目筛的苦荞麦麸粉用质量比1︰30的水于90℃浸提10 min,分别取体积分数80%的麦麸浸提液、15%的梨汁、5%西柚汁,并加入1%质量分数的蜂蜜,经海藻酸钠进行澄清过滤,所得苦荞麦麸复合饮料,其总黄酮含量为0.256 mg/mL,呈淡褐色、具有苦荞特有的清香。     

酶法水解苦荞麦蛋白制备生物活性肽的研究

介绍了采用2709碱性蛋白酶水解苦荞麦蛋白粉制备生物活性肽,并对其纯化效果、抗氧化性、氨基酸组成进行了研究,结果表明：苦荞麦活性肽经Sep Hadex G-25层析后基本上得到了纯化;苦荞麦活性肽对超氧阴离子自由基有很强的清除作用,清除率达到28．67%;氨基酸组成分析表明,苦荞麦活性肽由17种氨基酸组成,含有7种人体必需的氨基酸（Val、Ile、Leu、Phe、Met、Thr、Lys）,占苦荞麦活性肽氨基酸总含量的31．11%,具有较高的营养价值和较强的保健功能。     

微波协同L-苯丙氨酸处理对苦荞萌发中黄酮的影响

以川乔1号苦荞种子为研究对象,研究微波处理协同营养液L-苯丙氨酸(L-Phe)处理富集发芽苦荞黄酮效果.采用单因素和CCD响应面优化的方法,以苦荞芽中黄酮含量为指标,优化微波协同L-Phe处理下苦荞萌发富集黄酮的最佳工艺,并采用高效液相色谱法(HPLC)对苦荞芽中黄酮成分进行分析.结果表明,最优富集工艺为:苦荞种子经消...     

苦荞-小麦混合粉流变学特性及烘焙特性研究

该文对苦荞小麦混合粉粉质特性、拉伸特性进行系统研究。随着苦荞粉比例增加,形成时间、稳定时间缩短,弱化度上升,评价值下降,拉伸参数均呈下降趋势;且苦荞粉比例越大,下降幅度越大。另外,面包烘焙实验表明,苦荞添加量为10％和20％时,苦荞面包尚有较好烘焙特性,添加量增至30％时,烘焙特性显著下降,添加量达40％或50％时,烘焙特性极差。     

响应曲面法优化荞麦总黄酮的提取工艺

以米荞1号种子为原料,优化荞麦总黄酮的提取工艺条件。在单因素试验基础上,分别考察提取温度、提取时间、料液比和乙醇体积分数对荞麦总黄酮得率的影响,确定各因素的适宜水平。再根据Box-Behnken试验设计原理,利用Design-Expert 7软件进行响应曲面法试验,并建立总黄酮得率的二次回归方程,确定最佳提取条件。荞麦总黄酮的最佳提取工艺条件为提取温度68.5℃、提取时间90 min、料液比1:42(g/mL)、乙醇体积分数69%,在此条件下得到的实际总黄酮得率为2.157%,总黄酮得率的预测值为2.291%,两者基本吻合,表明此方法应用于荞麦总黄酮提取工艺的优化筛选可行。