排序方式: 共有78条查询结果,搜索用时 218 毫秒
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以‘紫娘喜’等6个海南主栽荔枝品种为试材,研究了果实采后贮藏过程中品质变化,结果表明:果实贮藏期间,6个品种的果实果皮褐变指数快速上升,好果率下降,同时,果皮失水率和pH值上升,果皮花色苷含量下降。无核荔枝果皮褐变最快,而紫娘喜果皮褐变最慢,主要与果皮失水速率有关。贮藏过程中供试品种果肉可溶性固形物(TSS)、可滴定酸(TA)和抗坏血酸(Vc)含量均下降,妃子笑、无核荔枝TSS/TA值呈先上升后下降趋势。新球蜜荔果肉TSS和TSS/TA值最高,TA最低;而紫娘喜果肉TA含量最高,TSS/TA值最低。紫娘喜与新球蜜荔Vc含量高于其它品种。 相似文献
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抗裂性不同的荔枝品种果皮发育过程中钙的分布动态研究 总被引:6,自引:0,他引:6
研究比较了抗裂荔枝品种‘怀枝’和易裂品种‘糯米糍’果皮中钙的含量, 并用电子探针技术(X - 射线电子散射能谱, X-Ray electron dispersive spectrum) 分析了两者钙的显微分布动态。研究表明,‘怀枝’积累钙的能力明显高于‘糯米糍’。两品种果皮发育早期, 海绵组织形成之前(花后10 d) , 在中果皮内层有大量的富钙区域, 随着果皮发育, 海绵组织形成, 该部位的富钙区消失; 而在果肉快速膨大前(花后52~66 d) , 内果皮成为钙信号最强的区域, 同时, 表皮细胞内积累大量的钙, 成为富钙细胞层, 表明钙可在果皮组织内再分布。果实发育后期(花后66~80 d) 表皮之下的厚壁组织钙分布最弱。本文还对两品种钙含量差异与种子发育的关系及各部位钙与果皮力学性能的关系进行了讨论。 相似文献
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黄冠梨果皮多酚氧化酶的酶学特性 总被引:2,自引:1,他引:2
[目的]研究黄冠梨果皮中多酚氧化酶(PPO)的酶学特性,为黄冠梨的贮藏保鲜和加工提供理论基础。[方法]采用分光光度法分别测定在不同反应pH值、不同反应温度、不同底物和抑制剂条件下的PPO活性。[结果]该酶的最适温度为25℃,50℃以上PPO活力明显受抑制;最适pH值为6.0;以邻苯二酚为底物时,Km=0.031 7 mol/L;以绿原酸作为底物时,Km=0.018 9 mol/L;在选定的浓度范围内(0.2~1.0 mmol/L),所用抑制剂的抑制能力从强至弱排列为L-Cys>Vc>Na2S2O3>NaHSO3>EDTA-Na2。较高浓度的CaCl2、NaCl也可对黄冠梨果皮PPO产生抑制作用。Cu2+能提高黄冠梨果皮PPO活性。[结论]绿原酸在黄冠梨果皮酶促褐变中的作用值得重视;采取调节pH值、热烫、添加安全抑制剂可以明显控制该PPO活性。 相似文献
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玉米Opaque2(O2)基因突变显著影响子粒胚乳中蛋白体形成、淀粉含量、氨基酸组成等,其中,赖氨酸含量提高使营养品质大幅度提升。通过回交转育的方法构建17份糯玉米o2近等基因系,对子粒表型、种皮厚度、百粒重和粗淀粉含量等性状分析。结果表明,与对照相比,16个近等基因系子粒明显皱缩、胚乳变为粉质,6个近等基因系种皮厚度增加,11个近等基因系百粒重显著降低,12个近等基因系子粒粗淀粉含量显著降低。由此表明,o2基因的导入对糯玉米子粒表型、产量、淀粉含量等主要起负调控作用,影响程度与导入背景密切相关。 相似文献
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玉米子粒的果皮是全部继承母本遗传信息的F1代组织[1].将玉米F1代种子的果皮分离并从中提取DNA,以160对SSR引物为基础对本单位自育和生产上大面积推广的5个玉米单交种及双亲进行特异引物的筛选.特异引物的标准是能同时区分双亲及杂交种.用这些特异引物对杂交种、亲本和从杂交种上分离的果皮DNA进行PCR扩增.实验表明,果皮中的DNA利用SSR分析,具有与杂交种母本完全相同的DNA指纹.可通过杂交种种子获得其母本的全套DNA及其DNA指纹图谱.在亲子鉴定、自交系DNA指纹库建立及品种权保护等方面具有应用前景。 相似文献
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Wheat bran tissue fractionation using biochemical markers 总被引:1,自引:0,他引:1
Carole Antoine Stphane Peyron Valrie Lullien-Pellerin Joël Abecassis Xavier Rouau 《Journal of Cereal Science》2004,39(3):467
Phenolic acid analysis of hand-isolated outer grain layers and endosperm led to the identification of markers of pericarp and aleurone layers, respectively. A new dehydrotrimer of ferulic acid (DHT) was found to be concentrated in the outer pericarp of wheat bran whereas p-coumaric (p-CA) acid was mainly in the aleurone layer. Phytates were also used as a marker of aleurone layer and starch as a marker of starchy endosperm. Biochemical markers constitute an original method for determining the histological composition of any technological bran fractions. A pin milling process was applied to coarse bran produced by a conventional milling process. Three different fractions (B1, B2 and B3) were obtained by sieving the bran products and then the smallest bran particle fraction (B3) was air-classified to obtain two particle size fractions (B3a and B3b with a D50 of 83 and 7 μm, respectively). The biochemical composition of these fractions was used to calculate the distribution of tissues according to the sieving process. The dissociation behavior of individual bran tissues upon mechanical fractionation was investigated in relation to particle size and discussed according to their mechanical properties. 相似文献
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The dynamics of pericarp development compared to that of the embryo, as well as the effect of pre-anthesis and post-anthesis shading on pericarp histogenesis and dry weight dynamics of fruits from two sunflower (Helianthus annuus L.) hybrid cultivars along three capitulum positions, peripheral, mid and central were studied. During fruit formation, the cell division phase of the carpel takes place before anthesis. Eight days after anthesis the pericarp reached its final size, while its cell wall's sclerification was almost complete 13 days after anthesis. Pre-anthesis shading affected the carpel cell division period reducing (17–33%) the number of pericarp middle layer strata and increased the thickenings of the cell wall of the mid (19%) and central (33–63%) fruits. In central fruits, the dry weight accumulation period was reduced. In contrast, post-anthesis shading reduced both the cell wall thickness (16–64%) and the number (38–58%) of pericarp middle layer sclerified strata of fruits in the three positions of the capitulum. In the mid and central fruits, the dry weight accumulation period extended 11–16 and 3–4 days, respectively, over those of the control. Both shading treatments produced thinner and lighter pericarps, but with different anatomical features that were associated with differences in the efficiency of use of the fruit for industrial oil extraction. 相似文献
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