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71.
Plasma Membrane Lipids Are the Powerful Components for Early Stage Aluminum Tolerance in Triticale 总被引:1,自引:0,他引:1
Tadao Wagatsuma Satoru Ishikawa Matsuo Uemura Wataru Mitsuhashi Takeshi Kawamura Md. Shahadat Hossain Khan Keitarou Tawaraya 《Soil Science and Plant Nutrition》2005,51(5):701-704
The order of aluminum (Al) tolerance in triticale lines (ST2>ST22) after re-elongation in an Al-free 0.2 mM calcium (Ca) solution for 9 h (Ca period) following 1 h pretreatment with 20 μM Al (Al period) agreed with that after 24 h of Al treatment. Permeability of the plasma membrane (PM) of root-tip cells after the Ca period was significantly increased in Al-sensitive ST22. Al was accumulated more heavily in the root-tip portion of ST22 than in that of ST2, although similar amounts of malic and citric acid anions were released from both triticale lines. We established a new system examining lipid permeability using synthesized nylon-2,8 ultrathin and porous capsules trapped previously with 0.1% (w/v) methylene blue solution and coated thereafter with PM lipid isolated from root tips by a newly developed technique. Permeability of the PM lipid measured with time in 0.2 mM Ca with or without 50 μM Al photometrically ( A 680 ) was significantly greater in Al-sensitive ST22 after 5 min of Al treatment. This is the first report to directly show the primary and early role of PM lipid in Al tolerance in triticale. 相似文献
72.
在豆奶中添加山药提取物和功能性甜味剂,控制乳酸菌可代谢糖含量制备一种具有降脂功效、后发酵质量稳定的无糖酸豆奶。采用筛选菌株,确定发酵剂;比较不同酸度下制品感官质量的变化,探讨后发酵质量的控制方法;以正交试验对配方优化;以高脂饲料建立高血脂大鼠模型,制品为干预饲料,了解制品对模型大鼠血脂的影响。结果表明:最佳工艺为豆奶75.6%,山药提取物12%,鲜牛奶5%,麦芽糖醇5.9%,嗜热链球菌H菌株发酵剂1%,保加利亚乳杆菌LB菌株发酵剂0.5%,配料接种后于42℃发酵10h。制品口感好,粘度好,后发酵酸度变化小,不产生涩味,质量稳定,对大鼠血清总胆固醇(TC)、甘油三酯(TG)水平均有显著降低作用,效果随剂量增大而增大,并显示添加山药提取物增效显著。本研究所确定生产工艺可较好地解决酸豆奶后发酵引起质量不稳定的问题,制品对高血脂大鼠的血脂具有很好的降低作用,可作为糖尿病人和高血脂病人的功能性食品来开发生产。 相似文献
73.
74.
小麦雄性不育系绒毡层异常代谢与小孢子败育的关系 总被引:1,自引:0,他引:1
【目的】研究小麦遗传型雄性不育系花药绒毡层降解及营养物质代谢,并揭示其与花粉败育的关系。【方法】以小麦S型1376不育系[(S)-1376(A)]及其保持系[(A)-1376(B)]为试材,在三核期分别用DAPI和KI-I2对花粉粒内淀粉积累进行染色观察;采用半薄切片技术对不育系(S)-1376和保持系1376绒毡层发育过程及多糖、脂类和蛋白等物质积累进行观察和比较;采用软件cellSens Entry和IPP 6.0分别计算图片中小孢子和绒毡层细胞的面积及分析各发育时期图像中的平均光密度值。【结果】与保持系1376比较,(S)-1376花粉粒被KI-I2染成浅黄色,表明三核期其花粉中无淀粉积累,花粉败育彻底;不育系(S)-1376绒毡层较保持系1376绒毡层细胞提前至四分体时期启动细胞程序化死亡(PCD)过程;不育系(S)-1376花粉核发育迟缓,大多发育至单核晚期停止分裂,仅少数可发育至二核期;(S)-1376小孢子在四分体时期和单核早期显著增大;绒毡层细胞在四分体时期也显著大于保持系1376绒毡层细胞。在(S)-1376花粉的发育过程中,除四分体时期外,其余各时期多糖含量(呈红色)均低于保持系对应的各发育时期,不育系(S)-1376绒毡层中多糖在四分体时期多于保持系,在单核早期显著降低。在花粉整个发育过程中,不育系(S)-1376花粉中被染成黑色脂类的含量明显低于保持系,不育系绒毡层中的脂类含量在各个时期也低于保持系。不育系(S)-1376小孢子母细胞四分体时期被染成蓝色的蛋白含量很高,但单核晚期显著降低;在绒毡层细胞中单核早期蛋白含量显著低于保持系,这可能暗示该时期保持系绒毡层开始启动降解。在花粉发育整个过程中保持系1376小孢子母细胞中四分体时期多糖和蛋白的含量都低于不育系(S)-1376,这可能与该时期不育系绒毡层提前降解需要大量的多糖和蛋白有关;单核晚期小孢子中的多糖、脂类和蛋白含量高于不育系,该时期是正常小孢子发育的关键时期,不育系中各种物质供应不足可能是导致花粉败育的主要原因。在二核期和三核期,不育系(S)-1376花粉营养细胞中大液泡不消失,细胞质内含物也不持续增加,淀粉粒、脂类等物质积累终止,最终导致小孢子内没有内含物的积累,呈空壳晶体状。【结论】小麦S型1376A不育系花药绒毡层提前降解所诱发的物质异常代谢,使小孢子在由单核晚期向二核期发育的过程中物质供应不足导致细胞核分裂异常,最终引起花粉败育。 相似文献
75.
This study determined the profile of hydrophobic phytochemicals (steroid-like components and lipophilic phenolics) and antioxidant potential (DPPH and Rancimat tests) of wheat grain in relation to sowing date (standard vs. delayed) using six cultivars of Triticum aestivum wheat grown in Poland. The study found that “sowing time” generally had a low impact on sterols, carotenoids, squalene and total lipophilic phenolics in wheat grain. The highest impact of “sowing time” was noted for α-tocopherol, C19:0 alkylresorcinol and campesterol. Delayed sowing reduced their content by up to 9%. The antioxidant potential of grain extracts obtained by the use of water-saturated butanol (WSB) was mostly cultivar-dependent (depending on assay: DPPH 56.3% and Rancimat 75.1% of explained variation, respectively). Wheat grain WSB extracts increased rapeseed oil induction time by up to 21% and their antioxidant capacity was up to 1.24 μM TEg−1. 相似文献
76.
T. A. Johnston M. D. Wiegand W. C. Leggett R. J. Pronyk S. D. Dyal K. E. Watchorn S. Kollar J. M. Casselman 《Ecology of Freshwater Fish》2007,16(3):295-306
Abstract – Understanding how maternal and ova traits influence offspring quality is a key issue in both ecological research and fish culture. We examined the survival and size at hatch of walleye embryos in relation to a suite of maternal and ova traits in laboratory incubation trials involving two native walleye populations. Ova were analysed for size, lipid content, fatty acid composition, soluble protein content and size composition, and mineral (Ca, Co, Cu, Fe, Mg, Mn and Zn) content. Embryonic survival (egg hatching success) varied most consistently with respect to spawning date and maternal age. Embryonic survival increased with maternal age, but other indices of maternal health, such as condition (residual mass at length) or somatic lipid content, did not account for significant amounts of variation. Indices of ova total lipid content, fatty acid composition and mineral composition explained significant variation in embryonic survival not accounted for by maternal age and spawning date, whereas indices of protein content and composition generally explained less variance. Both larval mass and length at hatch were primarily determined by ovum size, but length at hatch was also related to some aspects of ova fatty acid and mineral composition. 相似文献
77.
Wang Zhen-yu 《林业研究》2005,16(3):228-232
The effects of anthocyanin fromMalva sylvestris on plasma lipids and free radical were investigated by Reagent Kit method and in vitro assay. High fat model was set up with
albino rats that were fed with different dosages of anthocyanin fromMalva sylvestris (0.03 g·d−1, 0.04 g·d−1 and 0.05 g·d−1). The results showed that the total cholesterol was decreased by 19.7% at an anthocyanin of 0.04 g·d−1 and triglyceride was decreased by 34.4% at an anthocyanin of 0.05 g·d−1. In vitro assay, some indexes of anthocyanin were measured including the capability of scavenging free radical, reducing
force and the capability of anti-lipid peroxidation by orthophenanthroline Fe+2 oxidation-reduction method. The results indicated that the clearance rate of free radical reached to 43.46% when the content
of anthocyanin was 0.20 mg·mL−1 and the inhibition ratio of lipid peroxidation reached 18.82% when the content was 0.5 mg·mL−1. Therefore anthocyanin is a kind of natural and effective free radical remover and antioxidant and can prevent from the formation
of the thrombus and reduced the emergence of the cardiovascular disease.
Biography: Wang Zhen-yu (1957-), male, Prof. in Forestry College, Northeast Forestry University and Food Science Academy, Harbin Institute
of Technology, Harbin, P.R. China.
Responsible editor: Zhu Hong 相似文献
78.
血浆极低密度脂蛋白浓度的双向选择对肉鸡生长性能与血脂的影响 总被引:2,自引:0,他引:2
对零世代8周龄肉鸡血浆极低密度脂蛋白(VLDL)浓度进行降低腹脂的间接选择,明显改善了一世代低VLDL系鸡生长期饲料转化率,并对8周龄血浆甘油三酯、总脂浓度产生明显影响,但对8周龄血浆胆固醇浓度及各周龄体重未产生明显影响。低VLDL系鸡饲料转化率优于高VLDL系,肉仔鸡耗料比,5~9周龄高VLDL系明显高于低VLDL系(P=0.05),而7~9周龄高VLDL系显著高于低VLDL系(P<0.01)。8周龄血浆甘油三酯及总脂浓度,高VLDL系显著高于低VLDL系(P<0.001,P<0.01)。一世代高、低VLDL系血浆VLDL和腹脂的变异系数仍然很大,继续选择以培育脂肪更低、饲料转化率更高的低脂系是可能的,各周龄体重的变异系数不高(小于25%),但高、低VLDL系的变异系数大大高于总变异系数,表明选择使高、低VLDL系体重的整齐度降低,因此,继续对血浆VLDL浓度结合体重选择效果会更好。 相似文献
79.
80.
为了研究阿勒泰大尾羊不同部位脂肪组织沉积的变化规律,本试验选取90和270日龄健康、雄性阿勒泰大尾羊各6只,分别采集了90和270日龄时肾周脂、尾脂、腹部皮下脂肪组织样和血清,采用冰冻脂肪组织切片油红O滴染技术和Motic显微数字图像处理系统,测定脂肪细胞面积,并采用放射性免疫技术和酶联免疫法测定了血脂指标.结果显示,90日龄时,阿勒泰大尾羊尾脂脂肪细胞面积极显著高于肾周脂脂肪细胞面积(P<0.01),270日龄时,尾脂和腹部皮下脂肪脂肪细胞面积均极显著高于肾周脂脂肪细胞面积(P<0.01),但脂肪细胞的面积在尾脂和皮下脂肪之间无显著差异(P>0.05);与90日龄相比,270日龄阿勒泰大尾羊肾周脂脂肪细胞面积显著增高(P<0.05),而尾脂脂肪细胞面积极显著降低(P<0.01);90日龄阿勒泰大尾羊血清中leptin和HSL含量极显著高于270日龄(P<0.01),而血清中AST和ALT含量极显著低于270日龄(P<0.01).结果表明,阿勒泰大尾羊从90日龄生长至270日龄时,肾周脂脂肪细胞面积呈增加的趋势,而尾脂脂肪细胞的面积呈减少的趋势,这种变化可能与血清瘦素、激素敏感脂肪酶、天门冬氨酸氨基转氨酶和丙氨酸氨基转移酶含量有关. 相似文献