铬胁迫对罗汉果幼苗生理生化指标的影响     

张永霞  石贵玉李霞 张厚瑞 《中国农学通报》2011,27(2):12-16

重金属铬对植物的生长发育有非常重要的抑制作用。但是至今为止还没有铬对我国特有药用植物罗汉果植物影响的生理生化机理研究的报道。本实验以罗汉果幼苗为材料,对生长在添加0、50、100、150、200μmol?L-1浓度的重金属铬离子的培养基中生长15天的罗汉果幼苗的相关生理生化变化进行了详尽的分析变化。结果表明,随着铬离子浓度的增加,植株叶片的叶绿素含量、蛋白质含量、可溶性糖含量、超氧物歧化酶活性、过氧化氢酶活性一直下降;过氧化物酶活性先上升后下降;相反,脯氨酸和丙二醛含量则一直上升。表明铬离子 的毒害导致体内保护酶活性受到抑制,膜系统受到伤害,从而影响罗汉果幼苗生长。  相似文献   

A study on low dose cypermethrin induced histopathology, lipid peroxidation and marker enzyme changes in male rat     

V. Muthuviveganandavel 《Pesticide biochemistry and physiology》2008,91(1):12-16

The short term effect of low dose synthetic pyrethroid and insecticide α-cypermethrin was investigated in selected tissues of male albino Wistar strain rats. Cellular antioxidant activities, specific enzyme markers and tissue histopathology were studied using this compound at 5, 10, 25 and 50 mM at given time points during independent experiments. α-Cypermethrin was administered intradermally. Selective tissue responses were determined 6 h post administration employing control and experimental animals using established methods. Different doses of α-cypermethrin increased the malondialdehyde (MDA) content in the brain, heart, liver, kidney and testis of the male rats. Alanine transaminase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (GGT) enzyme activity levels were altered in these tissues and in the serum. Cytotoxic effects produced by α-cypermethrin were reflected in histopathology sections of the treated tissues. α-Cypermethrin decreased the cellular antioxidant activity, altered marker enzyme activity and effected histopathological changes in the treated animal tissues.  相似文献   

Key issues and challenges in whole wheat flour milling and storage   总被引：1，自引：0，他引：1  

Andres F. Doblado-Maldonado  Oscar A. Pike  Jess C. Sweley  Devin J. Rose 《Journal of Cereal Science》2012

Whole wheat flour is increasingly popular as research continues to reveal the benefits of whole grains and the food industry offers more whole grain options for consumers. The purpose of this review is to address milling and shelf-life issues that are unique to whole wheat flour. No standard methods are available for whole wheat flour milling, resulting in very different bran particle sizes. Literature suggests that moderate bran particle size is the best for bread production, while small particle size is better for non-gluten applications. Shelf-life of whole wheat flour is shorter compared to white flour due to the presence of lipids and lipid-degrading enzymes. Lipolytic degradation leads to reduction in functionality, palatability and nutritional properties. Strategies to stabilize whole wheat flour have focused on controlling lipolytic enzyme activity and have marginally succeeded.  相似文献   

Chemical composition of solid waste and effect of enzymatic oil extraction on the microstructure of soybean (Glycine max)     

Ângela Angeloni RovarisCarolinne Odebrecht Dias  Iria Pedroso da CunhaRejane Maria Cirra Scaff  Alicia de FranciscoCarmen L.O. Petkowicz  Edna Regina Amante 《Industrial Crops and Products》2012,36(1):405-414

The solid wastes were obtained from enzymatic extraction of soybean oil using four enzyme systems (Alcalase/Celluclast or Alcalase/Viscozyme L) each with two pH conditions: controlled or not controlled. This last option gave a better oil extraction, regardless of the enzymes used. The ash levels were higher for the enzyme systems subjected to controlled pH, depending on the buffer solutions used. The others constituents presented similar values between each other. The monosaccharides with highest concentrations were galactose, followed by glucose and arabinose. The physical analysis showed that the waste residues had good oil binding capacity. The SEM and epifluorescence microscopy revealed the microstructure of the beans and raw materials, as well as the changes caused by the extraction procedures.  相似文献   

采后嘎拉苹果果实细胞壁代谢及关键酶基因表达特性研究   总被引：2，自引：0，他引：2  

齐秀东  李海山  魏建梅  贾艳茹 《华北农学报》2012,27(2):55-60

以嘎拉苹果为试材,研究其果实细胞壁代谢及关键酶基因表达特性及受1-MCP、乙烯利和低温的影响效应。结果表明,常温下,嘎拉果实硬度变化与WSP显著正相关,与CSP和半纤维素显著负相关,与ISP的关系不大;1-MCP和低温处理显著抑制了WSP含量上升,减缓了CSP和半纤维素降解。嘎拉果实细胞壁酶中,β-Gal活性最高、增加最快,其基因表达亦迅速增加,α-L-Af活性和基因表达虽增加速率低于β-Gal,但二者变化规律相似,均显著受到1-MCP和0℃低温的抑制;PG和PME活性和基因表达量亦呈增加趋势,但未能完全被1-MCP处理和0℃低温所抑制;相关性分析表明,其细胞壁酶活性变化均与硬度呈显著负相关性,并显著受到1-MCP和低温的影响。但是,乙烯利处理虽对嘎拉果实软化有一定的促进作用,但效果不显著。  相似文献   

砂梨果肉褐变与酚类物质及相关酶活性的相关分析   总被引：3，自引：0，他引：3  

邹丽红  张玉星 《果树学报》2012,(6):1022-1026

【目的】为了探明砂梨褐变的内在机制,为砂梨贮藏与加工过程中品种选择和褐变控制提供理论依据,【方法】以11个砂梨品种的成熟果实为试材,测定总酚与酚类物质组成及含量、GSH含量、PPO、SOD、CAT、PAL、POD酶活性等相关指标。【结果】结果表明,不同品种酶促褐变程度有很大差别,‘新兴’和‘早生黄金’褐变较重,而‘秋黄’和‘丰水’较轻。绿原酸、儿茶素、芦丁和没食子酸是梨果肉中含量较高的酚类物质。总酚含量与果实褐变度相关性最高,绿原酸次之,儿茶素最低。【结论】梨果肉褐变相关酶活性与酚类物质组分及含量对其酶促褐变的影响程度因品种不同而存在差异。梨果肉酶促褐变与总酚和绿原酸含量的相关度高于与酶类的相关度。  相似文献   

Kinetics of acid phosphatase in calcium chloride extractable soil organic matter     

S. Marinari  G. Masciandaro  B. Ceccanti  S. Grego 《Soil biology & biochemistry》2008,40(9):2076-2078

The aim of this work was to compare the kinetic parameters of acid phosphatase (EC 3.1.3.2.) extracted from two forest soils under oak or pine. Soil was extracted with 4 mM CaCl₂ and the extract was divided into two fractions by filtration: one >0.2 μm containing microbial cells and soil particulates, and the other <0.2 μm containing fine particles and dissolved organic compounds of soil. The >0.2 μm fraction had higher K_m (0.26–0.82 vs. 0.12–0.39) and V_max (0.07–0.79 vs. 0.06–0.16) values than the <0.2 μm fraction, indicating a higher enzyme-substrate affinity and smaller amount of enzyme in fine particles and dissolved organic matter.  相似文献   

‘乾县火柿’常温保鲜贮藏研究   总被引：1，自引：1，他引：0  

田建文  许明宪  贺普超 《果树学报》1990,(3)

‘柿鲜Ⅰ’药剂处理刚转黄的‘乾县火柿’,不但保持了硬度,而且保持了可溶性固形物和维生素 C 含量.常温下贮藏三个月后,“柿鲜Ⅰ_4一Ⅰ_7”处理的果实硬度都在5.6kg/cm~2以上.可溶性固形物在15%以上.好果率大于86.2%.“柿鲜Ⅰ_7”处理的好果率高达99.2%.常规脱涩后硬柿风味不变.多聚半乳糖醛酸酶(PG)和纤维素酶对柿果的软化有直接作用.“柿鲜Ⅰ”的保鲜机理主要是抑制果实内部乙烯产生和减小呼吸强度.抑制 PG 和纤维素酶的活性,从而减缓不溶性果胶和纤维素的水解.  相似文献   

青香蕉和黄熟香蕉果皮感病过程中5种酶活性的变化   总被引：1，自引：0，他引：1  

黄雪梅  张昭其  季作梁 《果树学报》2005,22(6):662-666

以同一品种的未后熟的青香蕉和已黄熟的香蕉为材料,测定了接种炭疽病菌5d内果皮PPO、POD、SOD、PAL和LOX活性的变化,探讨与香蕉抗病性相关的酶类。结果表明,不论接种与否,青香蕉果皮中的PPO、POD和SOD的活性明显低于黄熟香蕉,而PAL和LOX活性高于黄熟香蕉;接种对PPO、POD和LOX活性影响不大,但引起SOD和PAL活性下降。青香蕉果皮中较低的PPO、POD和SOD的活性有利于活性氧和酚类物质的积累而产生过敏性反应,较高的PAL和LOX活性则利于苯丙烷类代谢和脂质过氧化,有利于抗病物质的形成。PAL和LOX是香蕉抗病性形成的关键酶。  相似文献   

Supplementation of dietary enzymes has varying effects on apparent protein and amino acid digestibility in reproducing sows   总被引：1，自引：0，他引：1  

A.L.P. de Souza  M.D. Lindemann  G.L. Cromwell 《Livestock Science》2007,109(1-3):122-124

The effects of two enzyme (Enz) products on ileal and total tract digestibility (ID and TTD) were evaluated in sows (n = 8) fed corn–soybean meal diets. Treatments were: 1) control diet; 2) control + Enz 1 (protease and cellulase activity); and 3) control + Enz 2 (xylanase activity). Ileal and fecal samples were collected at week 6–7 and 12–13 of gestation and week 2–3 of lactation. There were no improvements in digestibility during gestation. The ID% of dry matter (DM: 77.3, 79.3, 81.7) and N (81.2, 82.5, 84.3) as well as TTD% of DM (89.8, 90.7, 90.8) and N (89.0, 90.0, 90.6) during lactation were affected to varying degrees by the enzymes. The TTD of DM (P = 0.05) and N (P = 0.10) were positively affected by Enz 1. The ID of DM (P = 0.01) and N (P = 0.02) as well as TTD of DM (P = 0.05) and N (P = 0.02) were improved by Enz 2. The improvement in ID of N was not associated with any particular amino acids (AA) but represented small increases in ID of 8 of 10 essential AA with Enz 1 (P = 0.04) and 10 of 10 for Enz 2 (P = 0.01). The product containing xylanase activity, in particular, appears to have potential to increase digestibility of nutrients during lactation in sows.  相似文献