转录和蛋白质组学分析热空气处理对桃果实采后冷藏期间糖酸和酚类物质代谢的影响

桃果实采后低温贮藏易发生冷害,为研究热空气（hot air,HA）处理对桃果实冷藏过程中调控代谢途径的作用,本实验采用HA处理（40 ℃、4 h）桃果实,于（1±1）℃下贮藏35 d,每隔7 d取样并对可溶性糖、柠檬酸、苹果酸、总酚、总黄酮含量和花色苷含量等指标进行测定,同时选取样品进行转录组学和蛋白质组学分析。结果表明：HA处理可以有效抑制桃果实冷藏期间蔗糖、柠檬酸、苹果酸、总酚和总黄酮含量的下降,并抑制果糖和葡萄糖含量的上升,同时HA显著提高了桃果实花色苷的含量（P＜0.05）。转录组和蛋白质组学分析结果表明,HA处理调控的差异表达基因和蛋白主要集中于碳水化合物代谢和次级代谢物代谢途径;桃果实糖酸代谢变化主要与转化酶、蔗糖合酶、蔗糖磷酸合酶、苹果酸脱氢酶和柠檬酸合酶基因和蛋白的表达有关;HA通过上调苯丙氨酸解氨酶、香豆酸CoA连接酶、查耳酮合酶、二氢黄酮醇还原酶、花青素合成酶和类黄酮葡萄糖基转移酶的表达量,促进酚类、黄酮类和花青素的合成。综上所述,HA处理可以有效延缓桃果实采后糖酸和酚类物质含量的下降,并提高果实花色苷的含量。     

Influence of branch bending on sugar,organic acid and phenolic content in fruits of ‘Williams’ pears (Pyrus communis L.)

Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ‘Williams’ pears using high‐performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg^?1 fresh weight (FW) of fructose, 9.42 g kg^?1 FW of glucose, 7.94 g kg^?1 FW of sucrose and 24.59 g kg^?1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg^?1 FW, 2.24 g kg^?1 FW, 71.79 mg kg^?1 FW and 0.49 mg kg^?1 FW, respectively). Chlorogenic acid (280.86–357.34 mg kg^?1 FW) was the predominant phenolic acid, followed in concentration (mg kg^?1 FW) by syringic acid (95.46–131.32), epicatechin (46.55–83.09), catechin (25.67–44.81), vanillic acid (1.87–3.48), sinapic acid (0.83–1.72) and caffeic acid (0.72–1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry     

野山杏果肉总有机酸对高脂血症大鼠血脂及相关基因表达的影响

目的：研究野山杏果肉总有机酸（total organic acids from wild apricot,TOAWA）对高脂血症大鼠的降血脂作用及机理。方法：建立高脂血症大鼠模型,以灌胃血脂康大鼠为阳性对照组,利用试剂盒测定血脂浓度和载脂蛋白质量浓度;利用实时荧光定量聚合酶链式反应（real-time polymerase chain reaction,qPCR）测定大鼠肝脏过氧化物酶体增殖物激活受体α（peroxisome proliferator-activated receptor-α,PPAR-α）和低密度脂蛋白受体（low-density lipoprotein receptor,LDL-R）的基因表达水平;制作实验大鼠的肝脏组织切片,观察其对肝脏组织结构的影响;探究TOAWA对高脂血症大鼠血脂的影响及作用机理。结果：TOAWA能极显著降低灌胃高脂乳剂实验大鼠的总胆固醇、甘油三酯和低密度脂蛋白胆固醇（low-density lipoprotein cholesterol,LDL-C）浓度（P＜0.01）,显著降低载脂蛋白（apoprotein,Apo）B质量浓度（P＜0.05）,极显著升高ApoA-I质量浓度和ApoA-I/Apo-B（P＜0.01）,显著升高高密度脂蛋白胆固醇浓度（P＜0.05）。qPCR结果显示,灌胃高脂乳剂实验大鼠肝脏PPAR-α和LDL-R基因表达量降低,给予TOAWA干预后,实验大鼠肝脏PPAR-α和LDL-R基因表达量有明显的升高。肝脏组织切片的观察结果显示,TOAWA可明显改善肝功能。结论：TOAWA能调节高脂血症大鼠的血脂浓度,其作用与TOAWA调节Apo质量浓度、上调肝脏PPAR-α和LDL-R基因表达量及改善肝功能有关。     

中国野生葡萄果实基本品质、酚类物质含量及其抗氧化活性分析

中国野生葡萄资源丰富,但对其利用有限;为揭示不同种野生葡萄的品质差异及进一步利用奠定理论基础,本研究对中国野生葡萄的10个种(46个株系)和不同对照品种(4份材料)的基本品质、酚类物质含量及其抗氧化活性指标进行评价。结果表明:1)除刺葡萄外,中国野生葡萄的单果质量小于‘赤霞珠’;中国野生葡萄的皮果比高于‘赤霞珠’。2)中国野生葡萄和对照之间糖的组成相似,果糖与葡萄糖所占的比例没有差异,总糖含量显著低于‘赤霞珠’和‘户太8号’;除刺葡萄外,中国野生葡萄的总酸含量显著高于对照‘赤霞珠’和‘户太8号’,中国野生葡萄的酒石酸/苹果酸的比值低于‘赤霞珠’,说明中国野生葡萄属于高苹果酸型;河岸葡萄和圆叶葡萄的糖酸含量与中国野生葡萄的糖酸含量较接近;‘赤霞珠’和‘户太8号’属于高糖低酸型,中国野生葡萄属于低糖高酸型。3)中国野生葡萄的抗氧化活性和酚类物质的含量变异较大,大部分的野生葡萄与‘赤霞珠’的酚类物质含量和抗氧化活相近,但中国野生葡萄的花色苷含量高于对照的花色苷含量。综上所述,中国野生葡萄中的燕山葡萄、蘡薁葡萄和刺葡萄的品质较好,其与‘赤霞珠’和‘户太8号’的糖酸组分、酚类物质含量及抗氧化活性接近。     

Total phenols and antioxidant capacity in 10 Moroccan pomegranate varieties

The study focused on characterizing the 10 major Moroccan cultivars to acknowledge the quality and bioactive compounds of the fruits. The following determinations were assessed: pomegranate fruit maturity index, which truly defines juice taste, as well as organic acids and sugar contents, total phenols, and antioxidant activity of pomegranate juice. The cultivar per se (genotype) behaved as the most influencing factor conditioning pomegranate sugar and organic acids profiles, antioxidant activity, and total phenolics. The assessment of pomegranate chemical compositions implies the great potential of Moroccan cultivars for both fresh market and fruit processing. In fact, the "Hamde" sour cv. seems particularly suitable for juice production because of its high phenolics content. Additionally, the presence of bioactive compounds in pomegranate juices may encourage their consumption for potential health benefits. PRACTICAL APPLICATION: The cultivar per se (genotype) behaved as the most influencing factor conditioning pomegranate sugar and organic acids profiles, antioxidant activity, and total phenolics. Given the divergence observed on bioactive compounds concentrations and antioxidant activity among evaluated cultivars, the genotype factor should be considered as the most influencing factor in future breeding programs to enhance the synthesis of beneficial bioactive compounds.     

麦汁组成对啤酒有机酸的影响

有机酸是啤酒中的主要呈味物质,其含量和麦汁组成有着较密切的关系。麦汁中糖组成及氨基酸组成的改变,都会引起有机酸含量的变化,通过试验发现不同糖组成含量影响着有机酸的含量,同时氨基酸含量的高低也影响着啤酒最终的pH和总酸。     

南酸枣皮中酚类化合物体外模拟消化与溶剂提取的比较研究

对南酸枣皮进行体外模拟胃肠液消化与溶剂提取,研究不同提取方法对南酸枣皮中总多酚、总黄酮、原花青素释放的影响,并通过透析袋模拟肠道的吸收作用,考察其生物利用率。结果表明：体外消化过程中酚类化合物主要在胃部释放,经模拟胃液消化1 h后,总多酚、总黄酮、原花青素释放量分别为73.72、38.55、37.53 mg/g;肠液消化2 h后,总多酚、总黄酮释放量分别增加10.29 mg/g和8.78 mg/g,而部分原花青素发生分解,降幅为17.87%;透析袋内总多酚、总黄酮、原花青素释放量分别为5.94、5.48、3.21 mg/g,生物利用率分别为7.07%、11.59%和10.42%,因此黄酮类化合物最可能被人体吸收利用。不同处理方法的多酚类化合物的释放量为模拟胃肠液消化＜传统热水浸提＜超声波辅助乙醇提取（化学提取＞中药口服＞直接食用）。     

Nut and kernel traits and chemical composition of hazelnut (Corylus avellana L.) cultivars

BACKGROUND: Nut and kernel traits and chemical composition of 24 Italian and foreign hazelnut cultivars were analysed in 2002–2004 in order to study the effect of genotype and environment on nut quality. Nuts were sampled in a germplasm collection in the Italian province of Viterbo. RESULTS: Quantitative and qualitative determinations of sugars, organic acids and lipids revealed good nutritional and health potential of the nuts, with several differences among cultivars and years. The total contents of oil and sugars ranged from 563.69 to 656.36 g kg^?1 dry weight (DW) and from 39.80 to 59.51 g kg^?1 DW respectively. Fatty acid profile and sugar and total phenolic contents varied with the year. Significantly higher palmitic acid concentration (6.18%) was found in the hot summer year 2003; lower saturated fatty acid concentration (8.20%) and higher unsaturated/saturated acid ratio (11.27) were observed in the coolest year (2004). These differences among years were highlighted by discriminant analysis. CONCLUSION: The information relating to secondary components such as sugars, organic acids and phenolics was useful for discriminating among cultivars and years. Owing to the effect of these compounds on sensory attributes perceived by consumers, their concentration and the varietal differences can be considered primary determinants of nut quality and should be valued when planning the cultivar choice for new plantations. Copyright © 2008 Society of Chemical Industry     

国内啤酒有机酸组成及其综合评价

有机酸是对啤酒质量(口感和稳定性)有重要影响的一类物质,本文通过采用HPLC法测定国内市售的20种啤酒中主要有机酸的含量,且采用统计学中多指标综合评价法,建立了以6种有机酸(丙酮酸、苹果酸、乳酸、乙酸、柠檬酸和琥珀酸)为指标综合评价啤酒的方法。通过该方法可以对啤酒或者试验样品进行整体性比较和“优劣”排序,对研究啤酒中有机酸类物质的组成有重要意义。     

Color Development in a Model System During Frying: Role of Individual Amino Acids and Sugars

The color of fried potato products is limited by reducing sugars, but can be affected by free amino acids. Filter paper discs saturated with solutions of amino acids in combination with glucose, fructose and sucrose were fried in oil to investigate color formation. Four phases of color development were identified; equilibrium, lag, rapid and slow phase, corresponding to the water content of the system. Lysine, 7-aminobutyric acid and glycine produced most color and glutamic acid least. Fry color of glucose and fructose systems was very similar, but sucrose systems produced less color. Glucose and fructose systems were not affected by pH changes, but there was a slight effect on sucrose systems.     

青梅酱中的有机酸成分分析

分析了青梅酱的可溶性固形物、总酸、还原糖等主要成分,并采用高效液相色谱法对其中的草酸、酒石酸、苹果酸、乳酸、乙酸、柠檬酸及琥珀酸等7种有机酸进行了测定.有机酸分析采用的色谱柱为Zorbax SB-Aq C18(4.6x250 mm,5μm),流动相为0.01 mol/L KH2 PO4(pH 2.8),流速为1mL/m...     

基于Illumina MiSeq高通量测序技术分析贵州水豆豉中细菌多样性

以不同生产阶段的贵州水豆豉为研究对象，利用Illumina?MiSeq高通量测序技术，对贵州水豆豉自然发酵前后、调味后发酵3?个阶段的细菌菌群结构及多样性进行研究，并对其优势菌进行分离鉴定。结果表明，3?个样品共得到296?063?条有效数据，1?124?个操作分类单元。在3?个样品中共注释了6?个门类，21?个属类。在门水平上，随着发酵时间的延长，厚壁菌门（Firmicutes）丰度不断增加，变形菌门（Proteobacteria）不断减少。在属水平上，随着发酵时间的延长，芽孢杆菌属（Bacillus）丰度不断增加。后发酵24?h后（DCFW3），由于食盐、香辛料等抑菌成分的加入，细菌种类下降。此外，通过对贵州水豆豉中优势菌的分离纯化，利用VITEK?MS全自动微生物质谱从贵州水豆豉中获得4?株产蛋白酶较高的菌株，分别为枯草芽孢杆菌、解淀粉芽孢杆菌和蜡样芽孢杆菌。该研究为贵州水豆豉标准化和安全控制提供一定的参考依据。     

不同种类木瓜样品的总有机酸含量测定

建立木瓜中总有机酸含量的测定方法,并测定和比较皱皮木瓜和光皮木瓜共5个不同样品中的总有机酸含量.结果显示:24h内同一样品的测定结果稳定,RSD为1.28%,平均回收率为99.59%(n=6),RSD为1.548%;5个不同木瓜样品的总有机酸含量(以苹果酸酸计)在2.09%～3.47%之间.其中以皱皮木瓜1号的总有机酸含量最高(3.47%),皱皮木瓜4号最低(2.09%).     

Impact of shelf life on content of primary and secondary metabolites in apple (Malus domestica Borkh.)

In this study, we evaluated the changes in apple fruit quality during shelf life. After a month of cold storage, apples of cultivars "Jonagold" and "Golden Delicious" were exposed to ambient temperatures for 21 d, with subsequent sampling every 3 or 4 d. Fruit firmness, changes in amounts of sugars, malic acid, and phenolics were observed during shelf life. Chemical analyses were done with HPLC-PDA system. An interchange between various sugars was noticed, but in general, the sum of sugars remained at the same level. The content of malic acid remained stable or dropped, resulting in sweeter fruit. Levels of phenolics were more constant in the pulp of both cultivars analyzed, while in the peel, the changes were more pronounced. In the pulp, a peak in the content of hydroxycinnamic acids and flavanols was noticed on the 2nd or 3rd sampling and afterwards, the amounts remained constant. In the peel an initial decrease of all analyzed phenolic groups was observed in both cultivars, however it was more pronounced in "Jonagold." It can be concluded that changes in primary and secondary metabolites are not the main reason for the lower quality of fruit exposed to ambient temperatures. On the other hand, fruit firmness might be the limiting factor for shelf life duration.     

木瓜酒和木瓜醋发酵工艺及其有机酸组成分析

以光皮木瓜为原料,发酵木瓜干酒,再通过液态深层发酵酿制木瓜醋,确定了木瓜干酒和木瓜醋的发酵工艺,并对木瓜酒和醋主要有机酸进行分析。光皮木瓜经榨汁、调整糖度后进入发酵工序,酒精发酵采用带皮渣半固态发酵方式,条件为加水比例1.5∶1（m/m）、初始糖度18%、果酒干酵母接种量0.1%、在24 ℃条件下发酵64 h,木瓜酒酒度（乙醇体积分数）为9.45%。醋酸发酵采用半连续式液态深层发酵法,调整初始酒度7%,醋酸菌接种量10%,在34 ℃条件下醋酸发酵80 h,木瓜醋总酸度为4.52%;分割留种发酵仅需24 h即可完成醋酸发酵。采用反相高效液相色谱法从木瓜干酒和木瓜醋中检出10 种有机酸,分别是草酸、酒石酸、甲酸、苹果酸、α-酮戊二酸、乳酸、醋酸、柠檬酸、富马酸和琥珀酸。实验确定的发酵工艺以及有机酸的分析与鉴定可为木瓜干酒及木瓜醋产品的开发提供理论依据。     

卷烟中非挥发性有机酸、糖类、某些氨基酸和磷酸的同时测定

以山梨醇作内标,羟胺吡啶和BSTFA 1%TMCS为衍生化剂,采用GC法同时测定了国内外21种牌号卷烟中的木糖、阿拉伯糖、鼠李糖、果糖、甘露糖、半乳糖、葡萄糖、蔗糖、麦芽糖、天门冬氨酸、天门冬酰胺、丙二醇、丙三醇、乳酸、丙二酸、苹果酸、柠檬酸和磷酸。结果显示:①丙二醇和阿拉伯糖的RSD>10%,乳酸、天门冬酰胺、鼠李糖、半乳糖和麦芽糖的RSD>5%,其它成分的RSD<5%;②除丙二酸、半乳糖、鼠李糖、丙三醇和阿拉伯糖的回收率介于70%~75%外,其它组分的回收率>80%;③在所分析的卷烟样品中,进口混合型卷烟中柠檬酸、天门冬氨酸、天门冬酰胺、丙二醇和丙三醇含量较国产烤烟型卷烟的高,而糖类的含量则普遍较低,其它成分差别不大。