苜蓿褐斑病抗性与几种同工酶的关系   总被引：6，自引：1，他引：5  

袁庆华  桂枝 《草业学报》2003,12(6):58-63

以苜蓿5个品种在褐斑病抗性上存在差异的抗、感单株为材料，研究了接种病菌后苜蓿褐斑病抗性与多酚氧化酶(PPO)、过氧化物酶(POD)和超氧化物歧化酶(SOD)及其酶活性的关系。研究结果表明，褐斑病侵染后，苜蓿抗病株系和感病株系叶片中PPO、POD和SOD同工酶谱带多少和强弱存在明显的差异，即大部分抗病株系PPO、POD和SOD酶活性高于感病株系，并有新的同工酶带出现。PPO、POD和SOD在苜蓿抗褐斑病上可能起到重要作用，其同工酶谱带和酶活性的差异有可能做为鉴定苜蓿抗褐斑病的一种同工酶标记。  相似文献   

苹果梨中多酚氧化酶酶学特性的研究   总被引：26，自引：2，他引：26  

程建军  马莺  杨咏丽  凌海波  焦明晶  庄严 《园艺学报》2002,29(3):261-262

 以苹果梨中的多酚氧化酶为研究对象, 对其酶的活性变化及其特性的研究表明, 苹果梨中的多酚氧化酶的最适pH 值是4. 6 , 最适温度是40 ℃; 亚硫酸氢钠、维生素C、柠檬酸对苹果梨中多酚氧化酶的抑制作用依次减弱, 硫酸钠几乎无抑制作用。不同底物和同底物不同浓度影响多酚氧化酶特性。  相似文献   

外源绿原酸对苹果抗病相关酶的影响   总被引：4，自引：1，他引：4  

陈建中  章镇  黄赛芹  高志红 《果树学报》2003,20(1):67-69

采用离体培养方法对富士、红星和八棱海棠进行绿原酸处理,研究苹果在外源绿原酸处理下POD、PPO、PAL活性的动态变化以及绿原酸含量的变化。结果表明,富士以0.0001%绿原酸、红星以0.0008%绿原酸、八棱海棠以0.0004%绿原酸处理后,其PAL活性均显著提高,苹果体内也因此而提高了绿原酸水平。  相似文献   

鲜切莲藕中褐变因素分析的研究进展   总被引：1，自引：0，他引：1  

权美平 《保鲜与加工》2017,17(4):139-142

鲜切莲藕的褐变问题很大程度上限制了产品的生产和销售,分析其褐变因素对解决贮运保鲜问题具有重要意义。本文针对文献资料介绍的导致鲜切莲藕褐变的各因素(酚类物质、多酚氧化酶及环境条件)进行总结和分析,阐明各因素在保鲜贮藏中的变化规律,以期为莲藕加工提供理论借鉴和技术指导。  相似文献   

辣椒雄性不育系小孢子发育及脯氨酸等含量的研究   总被引：9，自引：1，他引：9  

孙立全  霍治军  常彩涛  张成合  李明  刘文明 《华北农学报》2003,18(4):39-41

对辣椒雄性不育系9601-A和保持系9601-B的小孢子发育过程及其脯氨酸、可溶性蛋白、粗蛋白的含量和过氧化物酶、多酚氧化酶的活性进行了观察和测定。结果表明，9601-A的雄性败育发生在减数分裂末期Ⅱ阶段，导致败育的主要原因是花药绒毡层细胞的高度液泡化，致使小孢子在发育过程中得不到正常的营养供给而死亡；不育系花药可溶性蛋白和粗蛋白(总蛋白)含量均显著低于其保持系，而过氧化物酶和多酚氧化酶的活性则高于其保持系。  相似文献   

Effects of fruit bagging on coloring and related physiology,and qualities of red Chinese sand pears during fruit maturation   总被引：1，自引：0，他引：1  

Chunhui Huang  Bo Yu  Yuanwen Teng  Jun Su  Qun Shu  Zaiquan Cheng  Liqiong Zeng 《Scientia Horticulturae》2009

Red Chinese sand pears (Pyrus pyrifolia Nakai) are particular to China. In order to determine the effects of fruit bagging treatments (including bag types, bag removal patterns and dates) on fruit qualities and to understand the mechanism of coloring of red Chinese sand pears, two experiments were carried out. In the first experiment, fruit of ‘Meirensu’ were firstly covered by light-impermeable paper bags with different levels of light permeable liners during their early development stage, then, the whole bag were/not removed or only the outer layer of bags were removed 3, 2 or 1 weeks before harvest. Thus, the fruit were/not totally re-exposed or were under different levels of sunlight transmission (80.31% or 34.71%). Non-bagged fruit were used as the control. Bagging treatments significantly affected the concentration of anthocyanin and the visual qualities of pear fruit. Compared to control, fruit re-exposed totally for 2 or 3 weeks accumulated the largest amount of anthocyanin and fruit receiving 80.31% and 34.71% of sunlight for 1–3 weeks could synthesize a little anthocyanin, indicating that high light intensity is imperative for coloring in red Chinese sand pears. Bagging treatments did not affect contents of total soluble sugars, but decreased organic acids contents in fruit. In the second experiment, fruit of ‘Meirensu’ and ‘Yunhongli No. 1’ were covered with only one type of light-impermeable bag during the early development stage and totally re-exposed after the bag removal 15 days before harvest. Fruit were then collected at different intervals to trace the time-course of coloring, and related physiology and inner qualities. With increasing time after the bag removal, the concentration of chlorophyll, carotenoid, flavonoid and total phenols changed little, but the concentration of anthocyanin accumulated extremely fast within 10 days after the bag removal in both cultivars and thereafter kept constant. ‘Yunhongli No. 1’ had higher anthocyanin contents and lower hue angle than ‘Meirensu’, indicating a higher potential of anthocyanin synthesis. After the bag removal, the sucrose contents and PAL activities increased gradually and correlation analysis revealed that they were highly correlated with anthocyanin accumulation in two cultivars. This study suggests that anthocyanin biosynthesis in red Chinese sand pears is a highly light dependent process and modified by genotypes. Based on the current results, in order to obtain red Chinese sand pear fruit with attractive appearance and good inner qualities, fruit must be covered with light-impermeable bags at the early stage of fruit development and the bag should be removed totally at least 10 days before harvest.  相似文献   

Dough rheological properties and noodle-making performance of non-waxy and waxy whole-wheat flour blends     

《Journal of Cereal Science》2017

Dough rheological properties and noodle-making performance of non-waxy whole-wheat flour (WWF) with partial- or full-waxy (PW- or FW-) WWF substitution were studied. The substitution levels were 0, 250, 500, 750, and 1000 g/kg, respectively. FW-WWF reduced the peak viscosity and pasting temperature of WWF blends as its substitution level was increased due to its higher proportions of B-type starch granules and short amylopectin chains, while PW-WWF increased peak viscosity with the increasing substitution level because of its higher amylopectin content. As demonstrated by farinograph and rheometer measurements, FW-WWF interfered with gluten development because of the increased competition for water by arabinoxylans and amylopectin; however, PW-WWF enhanced dough strength due primarily to its increased protein content. Consequently, FW-WWF showed a detrimental effect on cooked noodle texture as the cooked noodle hardness was reduced by 50% at the 1000 g/kg substitution level. In contrast, PW-WWF enhanced noodle integrity and elasticity by increasing cooked noodle cohesiveness and resilience by 10.1% and 14.8%, respectively, at the 1000 g/kg substitution level. The results suggest that with waxy WWF substitution, the changes in starch composition, arabinoxylans, and protein content could modify the interactions among flour components and influence the quality characteristics of noodle products.  相似文献   

北青龙衣褐变机制的研究     

谢荣娟  霍金海  王伟明 《中国农学通报》2017,33(12):129-136

北青龙衣在由鲜品到干品的贮藏期间会出现失水、颜色变深等褐变现象。研究该褐变过程发生的机制,为控制褐变、提高药材的稳定性提供试验依据。采用北青龙衣鲜果果皮,4℃低温贮藏,研究其褐变度(browning degree,BD)、多酚氧化酶(polyphenol oxidase,PPO)、苯丙氨酸解氨酶(phenylalanine ammonialyase,PAL)、过氧化物酶(peroxidase,POD)活性变化、丙二醛(malondialdehyde,MDA)、总多酚(total polyphenols,TP)、还原糖含量及维生素C(Vitamin C,VC)含量变化。试验数据显示果皮颜色变深、TP含量下降、PPO活性降低、PAL活性上升、SOD和POD活性先上升后下降、MDA含量升高、还原糖和VC含量下降。BD与PPO、SOD、POD活性和TP含量呈显著负相关,与PAL活性呈显著正相关,与VC和还原糖无显著相关性。北青龙衣贮藏过程中发生了酶促褐变和非酶褐变,且以酶促褐变为主,PPO在酶促褐变中可能起主要作用。  相似文献   

UV-C处理对水蜜桃果实冷害及贮藏品质的影响     

陈奕兆  李建龙 《中国果业信息》2013,42(1)

为了缓解水蜜桃果实采后冷藏保鲜对果实品质的负面影响,达到更好的保鲜效果,以江苏省张家港市的凤凰水蜜桃（Prunus persica)为实验材料,研究了不同剂量（0.5kJ/m2、1kJ/m2、1.5kJ/m2）UV-C对低温（3℃?℃）条件下水蜜桃果实冷害和品质的影响。实验结果表明：三种剂量的UV-C处理对水蜜桃均能有效减少果实的褐变,保存果实的可溶性固形物（TSS）,并明显延缓了丙二醛（MDA）、多酚氧化酶（PPO酶）的上升趋势;处理之间没有明显的效果差异,但1.5 kJ/m2处理的硬度值在5-20d之间均显著大于CK组（P<0.05）,表现出更好的抗软化能力;另外,UV-C处理易使果实相对电导率加速升高,该趋势随照射剂量的增大而增强。  相似文献   

Microbial HemG‐type protoporphyrinogen IX oxidase enzymes for biotechnology applications in plant herbicide tolerance traits     

Clayton T Larue  Joel E Ream  Xuefeng Zhou  Farhard Moshiri  Arlene Howe  Michael Goley  Oscar C Sparks  Steven T Voss  Erin Hall  Christine Ellis  Janice Weihe  Qungang Qi  Daniela Ribeiro  Xiaoping Wei  Shirley Guo  Artem G Evdokimov  Marguerite J Varagona  James K Roberts 《Pest management science》2020,76(3):1031-1038

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