首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 859 毫秒
1.
高压电场处理对贮藏番茄活性氧代谢的调节   总被引:7,自引:4,他引:3  
为探讨高压电场调控采后果实成熟衰老的作用机理,研究了交变电场和稳恒电场处理对采后番茄活性氧代谢的影响。试验结果表明:交变电场处理可诱导贮藏前期番茄超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,延缓贮藏后期SOD活性上升和CAT活性下降;稳恒电场处理对酶活性的诱导不显著。两种电场处理均延缓了过氧化物酶(POD)活性高峰出现的时间。稳恒电场处理果实整个贮藏过程中保持了高水平的抗坏血酸(AsA)以及还原型谷胱甘肽(GSH)含量。整个贮藏期间高压电场处理均显著抑制了番茄过氧化氢含量以及超氧阴离子的产生。  相似文献   

2.
Lactic acid bacteria (LAB) are generally sensitive to oxidative stress caused by reactive oxygen species (ROS). Antioxidant enzymes, especially superoxide dismutase (SOD) and catalase (CAT), can protect against ROS by eliminating superoxide and H(2)O(2), respectively. Lactobacillus rhamnosus is a valuable probiotic starter culture but is deficient in both SOD and CAT, and is thus likely to suffer from oxidative stress in industrial fermentation. To confer high level of oxidative resistance on L. rhamnosus , the SOD gene sodA from Streptococcus thermophilus and CAT gene katA from L. sakei were coexpressed in L. rhamnosus AS 1.2466. The enzyme activities of SOD and CAT were 147.80 ± 1.08 U/mg protein and 2.53 μmol of H(2)O(2) /min/10(8) cfu, respectively, in the recombinant L. rhamnosus CS. After incubation with 10 mM H(2)O(2), the survival ratio of L. rhamnosus CS was 400-fold higher than that of L. rhamnosus CAT. In long-term aerated conditions, viable cells of L. rhamnosus CS remained ~10(6) cfu/mL after incubation for 7 days, while no living cells of the control were detected. These results showed that the cooperation between SOD and CAT could significantly enhance oxidative resistance in L. rhamnosus . To our best knowledge, this is the first report of two synergistic antioxidant genes being coexpressed in the same Lactobacilli.  相似文献   

3.
Fresh peppers (Capsicum annuum L., variety California) in their green and red ripe stages were stored at 20 degrees C for 7 and 19 days to determine the effects of storage on whole fruit antioxidant capacity (TAA) and ascorbate (ASC) content, as well as on some antioxidant enzyme activities, such as catalase (CAT), superoxide dismutase (SOD), and those of the ASC-glutathione cycle. At least one Mn-SOD, two Fe-SODs, and three CuZn-SODs were detected in the fruit extract after native polyacrylamide gel electrophoresis. All of the SOD isozymes and glutathione reductase had higher activity levels in the red control fruits than in the green fruits, whereas the activities of monodehydroascorbate and dehydroascorbate reductase were higher in green fruits. Ascorbate peroxidase (APX) was found to be similar in both fruits. SODs, CAT, and APX seem to be involved in pepper fruit ripening and senescence during storage at 20 degrees C, perhaps influencing the active oxygen species levels in the fruit. TAA, as well as the ASC content, was higher in red peppers than in green, and storage increased the ASC in both green and red fruits.  相似文献   

4.
为研究壳聚糖-纳米氧化锌复合涂膜对甜樱桃贮藏期生理及品质的影响,以新鲜大连甜樱桃为材料,研究4℃条件下3种壳聚糖-纳米氧化锌复合涂膜处理(0.1%纳米氧化锌+0.2%壳聚糖、0.1%纳米氧化锌+0.5%壳聚糖、0.1%纳米氧化锌+0.8%壳聚糖)对甜樱桃的腐烂率、失重率、可溶性固形物、可滴定酸、维生素C(Vc)含量、呼吸强度、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量变化的影响。结果表明,0.1%纳米氧化锌+0.8%壳聚糖复配的壳聚糖-纳米氧化锌涂膜处理对甜樱桃果实的保鲜效果优于壳聚糖单膜处理(1.0%壳聚糖)。壳聚糖-纳米氧化锌复合涂膜处理能够使可溶性固形物、可滴定酸、Vc含量维持在较高水平,降低果实的腐烂率、失重率,有效延缓呼吸强度、MDA含量的上升及CAT活性的下降,抑制POD和SOD活性。在维持甜樱桃贮藏品质和延缓衰老方面,以0.1%纳米氧化锌+0.8%壳聚糖复配的壳聚糖-纳米氧化锌复合膜处理的保鲜效果最好。本研究结果为改性壳聚糖涂膜在甜樱桃贮藏保鲜中的应用提供了理论依据。  相似文献   

5.
用剂量为5、10、15和30Gy的60Coγ射线辐照羽化后1~2d雄果蝇,以探讨γ辐射对果蝇寿命及其子代生理变化趋势的影响,同时也为防治害虫提供参考。结果显示,辐照后各处理组果蝇的平均寿命、最高寿命及90%死亡时间均显著缩短(P0.05),30Gyγ射线使得雄果蝇初期的存活率急剧下降,但寿命变化与其他剂量组差异不显著。不同剂量辐照后的雄蝇与未经辐照的处女蝇交配,其生殖量在交配第7天前低于对照组,但第11天后辐照组均高于对照组。辐照组F1代体重增加,生理应激能力下降。  相似文献   

6.
不同抗旱性小麦叶片膜脂过氧化的氮素调控机制   总被引:3,自引:0,他引:3  
在田间条件下研究了施氮对不同抗旱性冬小麦叶片全生育期黄嘌呤氧化酶(XOD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性以及过氧化氢(H2O2)和丙二醛(MDA)含量的影响。结果表明,施氮提高了叶片CAT和SOD活性,降低了XOD活性和MDA含量,以N180处理效果最明显,而且产量最高,表明N180处理对小麦膜脂抗过氧化能力和产量形成最为适宜;不施氮(N0)处理条件下,旱地品种较水浇地品种具有较高的保护酶系活性和较低的XOD活性、MDA含量。而适量氮素能够提高叶片保护酶系活性和降低XOD活性、MDA含量,所以氮素能够通过提高叶片膜质抗过氧化能力来增强小麦对干旱的适应。由于降低了超氧阴离子的生成量,使XOD活性降低和CAT活性提高,H2O2和MDA含量维持在较低水平,最终提高小麦产量。  相似文献   

7.
采用果实薄片培养试验研究不同钙浓度(0、1和10 mmo1/L CaCl2 ;5 mmo1/L EGTA)和处理时间(6、12、24和48 h)下苹果果实活性氧代谢特征;运用荧光定量PCR方法分析苹果超氧化物歧化酶(SOD)、过氧化氢酶(CAT)基因在分子水平的表达。高钙处理12 h后,SOD酶的活性显著增加,O2.-产生速率显著下降;高钙处理24 h后,CAT酶的活性显著增加,H2O2含量显著下降;缺钙处理下SOD酶和CAT酶的活性受到抑制,O2.-形成速率和H2O2含量显著增加。基因表达实验显示,高钙处理12h后,SOD基因的表达量增加,与SOD酶活性变化一致,说明SOD酶的活性取决于SOD基因的表达量;高钙处理12 h后,CAT1基因的表达量增加,而CAT酶的活性是在加钙处理24 h后显著增加,说明CAT酶的活性并不完全取决于CAT1基因的表达量,推断其酶活性还取决于该基因翻译后的修饰调控。上述研究表明苹果外源补钙通过在分子水平上调SOD和CAT1基因表达量来激活SOD和CAT酶的活性,有效减少体内活性氧积累,确保果实生理代谢平衡。  相似文献   

8.
Fruit of two apricot cultivars 'Bagheri' and 'Asgarabadi' were treated with putrescine (Put) or spermidine (Spd) at 1 mM and then were stored at 1 °C for 21 days. Fruit were sampled weekly and stored 2 days at 20 °C for shelf-life study. The treatments reduced ethylene production and maintained the firmness and color of the fruit. Peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), and polyphenol oxidase (PPO) activities and total phenol (TP) concentrations were measured during storage. Both cultivars showed chilling injury (CI) incidence, and the severity in control fruit was higher than either Put or Spd treatments. CI incidence in Spd-treated fruit was lower than that of Put-treated fruit. Polyamine (PA) treatment generally increased antioxidant enzyme activity of fruit during storage. PA treatments may help maintain the quality of apricot fruit during storage by inhibiting ripening and decreasing CI incidence.  相似文献   

9.
生长期喷钙提高锦橙果实品质及延长贮藏期   总被引:2,自引:0,他引:2  
探讨钙对柑橘果实贮藏品质及衰老的影响,为合理调控柑橘钙素营养、延长果实的贮藏保鲜期提供理论和技术支撑。通过在北碚447锦橙(Citrus sinensis Osbeck cv.Jincheng)生长的不同时期进行树体补钙,研究钙对果实贮藏品质及酶活性的影响。结果表明,在锦橙的生长期喷钙能提高果实钙含量,抑制果实贮藏过程中维生素C等物质的氧化分解,提高果实可溶性固形物含量和糖酸比,改善果实品质。不同时期喷钙均能提高果实中抗氧化酶(CAT、SOD)活性,降低细胞壁水解酶(PG、CX)、过氧化物酶(POD)活性,减轻脂质过氧化程度,果胶的分解转化速度减慢,丙二醛、可溶性果胶的含量明显降低,从而维持果皮具有一定的强度,延缓了果实的衰老,降低烂果的发生率,延长了果实的贮藏保鲜期。其中以幼果期喷钙在提高果实钙含量、延长贮藏期等方面的效果较好,其次是果实膨大期喷钙,成熟期喷钙效果最差。在幼果期和果实膨大期喷钙是提高果实品质、延长采后果实贮藏保鲜期的重要措施。  相似文献   

10.
采用急性染毒方法研究Cd2+胁迫对不同发育阶段中华稻蝗SOD、CAT、POD活性的影响。结果表明,在Cd2+的作用下,不同发育阶段中华稻蝗体内SOD、CAT、POD活性均发生变化。SOD、CAT、POD 3种酶对Cd2+有一定的耐受性:当Cd2+浓度在这3种酶的耐受范围内酶活性提高,反之酶活性降低。Cd2+对不同发育阶段虫体3种抗氧化酶的影响不同:3龄若虫SOD、POD活性最高;雌性成虫CAT活性最低,而3龄雄性若虫CAT活性最高。  相似文献   

11.
Arbuscular mycorrhizal (AM)-mediated plant physiological activities could contribute to plant salt tolerance. However, the biochemical mechanism by which AM fungi enhance salt tolerance of halophytic plants is unclear. A pot experiment was conducted to determine whether salt tolerance of the C 3 halophyte Suaeda salsa was enhanced by the AM fungus Glomus mosseae. When 60-day-old S. salsa seedlings were subjected to 400 mmol L-1 NaCl stress for 35 days, plant height, number of leaves and branches, shoot and root biomass, and root length of G. mosseae-colonized seedlings were significantly greater than those of the nonmycorrizal seedlings. Leaf superoxide dismutase (SOD) activity at all sampling times (weekly for 35 days after salt stress was initiated) and leaf catalase (CAT) activity at 2 and 3 weeks after salt stress was initiated were also significantly enhanced in G. mosseae-colonized S. salsa seedlings, while the content of leaf malondialdehyde (MDA), a product of membrane lipid peroxidation, was significantly reduced, indicating an alleviation of oxidative damage. The corresponding leaf isoenzymes of SOD (Fe-SOD, Cu/Zn-SOD1, and Cu/Zn-SOD2) and CAT (CAT1 and CAT2) were also significantly increased in the mycorrhizal seedlings after 14 days of 400 mmol L-1 NaCl stress. Our results suggested that G. mosseae increased salt tolerance by increasing SOD and CAT activities and forming SOD and CAT isoforms in S. salsa seedlings.  相似文献   

12.
以水稻离体叶片模拟叶片衰老过程,通过不同的硅处理方式,研究水稻衰老过程中硅对叶片体内丙二醛(MDA)含量以及过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性的影响。结果表明,无论是在叶片离体前还是离体后进行硅处理,都能增加丙二醛(MDA)的含量,提高过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性,施硅处理尤其对过氧化氢酶(CAT)活性的影响较为显著。因此,硅可通过参与植株体内代谢并调节抗氧化系统酶活性,来延缓水稻的衰老。  相似文献   

13.
为研究饲料中不同枣粉添加量(0,10%,15%,20%和25%)下陕北白绒山羊肉的抗氧化性能,选取初始体质为(20.15±1.63)kg的40只6月龄健康白绒山羊,随机分为5组,分别饲喂无枣粉添加(对照组)、10%(I试验组)、15%(II试验组)、20%(III试验组)、25%(IV试验组)的日粮,饲养试验预试期10d,饲喂期70d;分别饲喂基础日粮和试验日粮,测定瘤胃降解率和生长性能。饲喂试验结束后屠宰全部试验羊,以山羊背最长肌为试验材料,分别测定羊肉的色泽、丙二醛、肌红蛋白氧化状态、抗氧化能力和抗氧化酶基因并进行比较分析。结果表明:随着枣粉添加量增加,绒山羊的干物质消化率(Dry Matter Digestibility,DMD)、粗蛋白消化率(Crude Protein Digestibility,CPD)、平均日采食量(Average Daily Feed Intake,ADFI)、平均日增重(Average Daily Gain,ADG)、肌红蛋白(Myoglobin,Mb)含量、超氧化物歧化酶(Superoxide Dismutase,SOD)和SOD基因表达量逐渐增加,而料肉比(Feed Conversion Ratio,FCR)和丙二醛(Malondialdehyde,MDA)含量逐渐降低;其中III组的DMD、ADFI和ADG均显著高于对照组(P 0.05)。III组的红度值、肌红蛋白含量、氧合肌红蛋白(Oxymyoglobin,OMb)相对含量显著高于对照组、I和II组(P 0.05);在抗氧化中,III组的SOD酶活、谷胱甘肽过氧化物酶(GlutathionePeroxidase,GSH-Px)活力显著高于对照组和I组(P0.05);III组的过氧化氢酶(Catalase,CAT)活力显著高于对照组、I和IV组(P0.05);在抗氧化酶基因中,III组的SOD、GSH-Px基因表达量显著高于对照组、I和II组(P 0.05),而脂氧合酶(Lipoxygenase,LOX)基因表达量低于对照组、I和II组(P0.05)。总体上饲料中添加枣粉能够增加羊肉的抗氧化机制,抑制脂质氧化并改善肉色,在枣粉水平为20%时,能有效缓解山羊肉组织中的氧化应激,提高抗氧化能力。  相似文献   

14.
镁对大豆叶片细胞膜透性和保护酶活性的影响   总被引:5,自引:1,他引:5  
采用溶液培养方法研究不同的镁水平对两个大豆品种在五叶期和盛花期叶片细胞膜透性和保护酶活性的变化。结果表明,在缺镁胁迫下,大豆叶片的质膜透性(MP)和丙二醛(MDA)含量显著增加,产生的活性氧物质诱导超氧化物歧化酶(SOD)和过氧化物酶(POD)活性升高,而过氧化氢酶(CAT)活性下降;而施镁则能明显降低大豆叶片MP和MDA含量,提高CAT活性,有利于大豆抗膜脂过氧化胁迫。在施镁1~10.mg/L浓度下,大豆叶片的质膜透性和MDA以及SOD和POD活性均达最低值,而CAT活性则达最高值。说明在低镁胁迫下,大豆叶片的CAT活性受到抑制,而适量施镁则大大增强了CAT活性,有利于大豆体内活性氧的清除和抗逆境胁迫能力的提高。各处理下,大豆盛花期SOD和CAT活性明显降低,说明随着时间的延长,大豆叶片细胞内产生过多的活性氧超出了酶的防御能力,造成了酶活性伤害,而POD活性则变化不大;说明POD对活性氧具有较强的耐受性,是盛花期时起主要清除活性氧的作用的保护酶。本试验表明,大豆体内保护系统所存在的酶类在抵御逆境胁迫中相互协调,协同抗氧化。  相似文献   

15.
为提高柑橘的保鲜效果,本试验以椪柑为材料,研究柠檬精油及其与壳聚糖、氯化钙和纳他霉素复配对果实采后贮藏品质的影响。结果表明,柠檬精油及其与壳聚糖、氯化钙和纳他霉素复配可以降低果实腐烂率和失重率,抑制果实呼吸速率,延缓果实可滴定酸(TA)和维生素C(Vc)的降解,更好地维持果实营养价值和感官品质;柠檬精油及其复合物可提高果实超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性,抑制果皮相对电导率的上升和果肉丙二醛(MDA)含量的积累。其中,1%柠檬精油+1%壳聚糖+1%氯化钙+300 mg·L-1纳他霉素复配对椪柑保鲜效果最好,其果实Vc和TA含量最高,腐烂率、失重率、果皮相对电导率和果肉MDA含量最低,且在维持抗氧化酶(CAT、SOD和POD)活性方面的效果最优。本研究结果为柠檬精油及其复配物作为防腐剂保鲜果蔬提供了理论支撑。  相似文献   

16.
R. XU  M. YAMADA  H. FUJIYAMA 《土壤圈》2013,23(2):213-222
Salinity stress is a major factor limiting the growth of turfgrass irrigated with recycled wastewater. The change in lipid peroxidation in terms of malondialdehyde (MDA) content and the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxide (APX) and glutathione reductase (GR) in the shoots and roots of Kentucky bluegrass and tall fescue were investigated under salinity stress. Plants were subjected to 0, 50, 100, 150 and 200 mmol L 1 NaCl for 40 d. The MDA content under salinity stress was lower in tall fescue than in Kentucky bluegrass in both shoots and roots. Activities of SOD in the shoots of both species increased with salinity stress. The activities of CAT and APX decreased in Kentucky bluegrass, but no significant difference in the activities of CAT and APX was observed in tall fescue. The activities of SOD, CAT and APX in the shoots of tall fescue were higher than those in Kentucky bluegrass. In the roots of Kentucky bluegrass, SOD and GR activities increased and CAT and APX activities decreased in comparison with the control. In the roots of tall fescue, salinity increased the activities of SOD, CAT, and APX. These results suggested that tall fescue exhibited a more effective protection mechanism and mitigated oxidative stress and lipid peroxidation by maintaining higher SOD, CAT and APX activities than Kentucky bluegrass.  相似文献   

17.
甜菜M14品系与二倍体栽培甜菜耐盐性的比较研究   总被引:2,自引:0,他引:2  
【目的】甜菜属于耐盐碱作物,通过比较两个优质甜菜材料的耐盐性,为甜菜育种提供科学依据。【方法】本试验以甜菜M14品系(18+1条染色体)和来自同一亲本分离得到的二倍体栽培甜菜(18条染色体)为试验材料,在正常和200 mmol/L NaCl胁迫条件下进行水培试验。在处理0、1、3、5、7天后,采集幼苗样品,测定株高、根长,分析K^+、Na^+、丙二醛(MDA)和甜菜碱含量,测定主要抗氧化物酶基因(SOD、CAT、APX、GR)和甜菜碱合成基因(CMO、BADH)的转录水平及以上6个基因编码酶活性。【结果】1)正常条件下,两个甜菜材料的株高和根长均无明显差异;200 mmol/L NaCl胁迫条件下,M14品系的株高和根长均优于二倍体。2)正常条件下,M14品系与二倍体的根吸收K^+和Na^+的能力相似,代谢过程中产生甜菜碱的量相当;200 mmol/L NaCl胁迫条件下,两个甜菜材料根中的K^+、Na^+含量差异不显著,而M14品系根中的甜菜碱含量高于二倍体。3)正常条件下,两个甜菜材料根中的SOD、CAT、APX、GR、CMO和BADH基因转录水平差异均不显著;200 mmol/L NaCl胁迫条件下,M14品系根中的SOD和GR基因转录水平均在第1天时高于二倍体,CAT、APX、CMO和BADH基因转录水平在第3~5天显著高于二倍体。4)正常条件下,两个甜菜材料根中SOD、CAT、APX、GR、CMO和BADH活性差异不显著;200 mmol/L NaCl胁迫条件下,M14品系根中各酶活性均显著高于二倍体。【结论】在200 mmol/L NaCl胁迫条件下,甜菜M14品系根部的甜菜碱含量较高,抗氧化物酶基因转录水平及酶活性均显著高于二倍体,表现出更高的耐盐性。  相似文献   

18.
为确定抗病基因PnAG3与花生抗旱性关系,本实验利用土壤盆栽试验,通过控水模拟干旱条件,利用荧光定量方法分析不同程度干旱、苗期不同抗病花生(Arachis hypogaea L.)品种PnAG3基因的表达变化,同时测定它们耐旱生理指标的变化。结果表明,抗病品种在中度干旱胁迫下超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)活力分别升高了3.15、2.55和4.95倍,而不抗病品种在3种处理下差异不显著;丙二醛(malondialdehyde,MDA)含量在不同干旱程度下均有所升高,且不抗病品种升高幅度大于抗病品种;基因PnAG3的表达量在抗病品种中要高于不抗病品种,但抗病品种在中度和重度干旱胁迫下基因表达量出现的峰值较不抗病品种早,与CAT活性的变化相似。整体来看,SOD呈持续上升趋势,而基因PnAG3表达量、POD、CAT和MDA呈现先上升后下降的趋势,结合耐旱生理指标及抗病相关基因PnAG3的变化情况,基因PnAG3表达量变化与耐旱生理指标的变化有相关性,且在抗病品种中基因PnAG3的表达量大于不抗病品种,推测基因PnAG3的功能与花生抗逆性有关。本研究为进一步研究花生抗性育种和种质筛选提供依据。  相似文献   

19.
为探讨高湿贮藏对减轻茄子冷害的作用及其与抗氧化系统的关系,本试验将茄子果实分别放置于4℃的干雾控湿高湿冷库(相对湿度96%~99%)和低湿冷库(相对湿度70%~75%)中贮藏15 d,每隔3 d进行取样测定,比较分析相关指标的变化。结果表明,与低湿贮藏相比,高湿贮藏能显著抑制茄子果实冷害指数、相对电导率和失重率的上升(P<0.05),保持茄子果实较高的硬度及总酚和花青素含量。同时,高湿贮藏能显著提高茄子果实中超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化氢酶(CAT)和过氧化物酶(POD)等抗氧化酶的活性(P<0.05),抑制过氧化氢(H2O2)和超氧阴离子( O 2 - · )的产生,保持更高的1,1-二苯基-2-三硝基苯肼(DPPH)和羟基自由基清除能力。上述结果表明,高湿贮藏可维持茄子果实较高的抗氧化系统活性,从而抑制活性氧对茄子的伤害,减轻果实冷害。本研究为高湿贮藏在茄子果实采后保鲜中的应用提供了一定的依据。  相似文献   

20.
丁香叶油及其与壳聚糖和CaCl_2复配对砀山酥梨的保鲜效果   总被引:3,自引:1,他引:2  
研究了砀山酥梨用丁香叶油及其与壳聚糖和CaCl2复配剂涂膜处理后低温冷藏(0℃~2℃)的保鲜效果。结果表明,丁香叶油及其与壳聚糖和CaCl2复配剂对砀山酥梨具有明显的保鲜作用,其中以DKLO2(40μl/L丁香叶油+1%壳聚糖+1%CaCl2)浸涂保鲜效果最好,可显著延缓砀山酥梨采后硬度和可溶性固形物的下降,可使呼吸高峰较对照推迟10d出现,并能显著抑制MDA含量的增加及相对电导率和PPO活性的上升;贮藏至第30天,SOD活性较对照增加95.61%,CAT和POD活性分别是对照的2.22及4.28倍。DKL02浸涂处理可使砀山酥梨的贮存期达7个月。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号