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101.
为了研究营养元素硝酸铵、硝酸钾、葡萄糖酸钙对蓝莓离体繁育的影响,以蓝莓‘夏普蓝’继代增殖苗为试材,就添加了不同浓度的硝酸铵、硝酸钾、葡萄糖酸钙的改良培养基对蓝莓离体增殖的新梢形态及体内超氧化物歧化酶(Superoxide Dismutase,SOD)、过氧化物酶(Peroxidase,POD)、过氧化氢酶(catalase,CAT)活性的影响情况进行了试验研究。试验结果表明:当培养基中硝酸铵的浓度为600 mg·L~(-1)、硝酸钾的浓度为400 mg·L~(-1)、葡萄糖酸钙的浓度为600 mg·L~(-1)时,新梢植株发育良好,植株长势健壮,颜色正常;发育正常的新梢其SOD活性间不存在明显差异,其POD活性间不存在明显差异,其CAT活性间也不存在明显差异;而且其SOD、POD、CAT活性均明显高于发育不正常的新梢。分析结果表明:矿质营养元素能调节蓝莓不定芽抗氧化酶活性;而稳定、平衡的抗氧化酶活性又能促进不定芽的发育。  相似文献   
102.
For trace elements, such as copper (Cu) and zinc (Zn), the bioavailability of these elements, Cu and Zn, in biosolids is important because both are essential elements and both are potential contaminants when biosolids are land applied. A greenhouse study was conducted in factorial experiment based on a completely randomized design (CRD) with four replications on a soil treated with four rates of Cu (0, 50, 100, and 150 mg/kg) and four rates of Zn (0, 150, 300, and 450 mg/kg) on celery plants to investigate the distribution and mobility of these elements as well as growth and antioxidant changes of celery. The results of antioxidant changes were inconclusive due to irregular changes with Zn and Cu applications. However, generally the results show that Cu did not affect superoxide dismutase (SOD) or peroxidase (POD) activities in most of the treatments. On the other hand, Zn stimulated SOD and POD activities in most of the treatments. The photosynthesis rate decreased with the applications of Cu and Zn at the rates above 100 and 300 mg/kg and increased in low Cu concentration (50 mg/kg) compared to S (soil without biosolid).  相似文献   
103.
Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is an important disease affecting sugar beet. Control is achieved through planting of resistant varieties; however, following the introduction of Rz1, new pathotypes that overcome resistance have appeared. To understand how BNYVV overcomes resistance, we examined quantitative protein differences during compatible and incompatible interactions when sugar beet is infected with either a traditional A-type strain or with an Rz1 resistance breaking strain. Proteomic data suggest distinct biochemical pathways are induced during compatible and incompatible sugar beet interactions with BNYVV. Pathways including the detoxification of reactive oxygen species, UB/proteasome, and photosynthesis should be studied in more depth to characterize roles in symptom development.  相似文献   
104.
Differences in virulence between Fusarium sulphureum and Fusarium sambucinum were compared. Changes in reactive oxygen species production and metabolism in inoculated slices of potato tubers were also compared. The result showed that Fusarium infection induced significant production of ROS, lipid peroxidation and loss of cell membrane integrity, but low activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX). Compared to F. sambucinum, F. sulphureum led larger lesion diameters on potato tubers and slices. It resulted in more superoxide anion (O2-) and earlier peak of hydrogen peroxide (H2O2), but lower activity of catalase (CAT) and APX, and accompanied with higher malondialdehyde (MDA) content and lower cell membrane integrity. These findings suggested that overproduction of ROS involved in the pathogenicity of Fusarium in potato tubers.  相似文献   
105.
BALB/c小鼠肺组织中氧化及抗氧化系统的动态研究   总被引:2,自引:1,他引:1  
为探讨BALB/c小鼠正常生理状况下肺组织中的氧化及抗氧化系统的动态变化规律,采用分光光度计法分别测定了肺组织中的黄嘌呤氧化酶(xanthine oxidase,XOD)活性、丙二醛(malondialdehyde,MDA)含量、超氧化物歧化酶(superoxide dismutase,SOD)活性变化。结果表明,在第3、6、7、12天BALB/c小鼠肺组织的XOD活性、MDA含量、SOD活性均无显著差异(P>0.05)。说明生理状态下,BALB/c小鼠肺组织中自由基的产生与清除的酶系统之间维持动态平衡。  相似文献   
106.
超氧化物歧化酶(SOD)是生物体内的重要保护性酶类。采用RT-PCR方法克隆了柞蚕(Antheraea pernyi)铜锌超氧化物歧化酶(Cu/Zn-SOD)基因的ORF序列。生物信息学分析表明,该序列共编码154个氨基酸,具有Cu/Zn-SOD的保守性结构特征,与家蚕(Bombyxmori)、美国白蛾(Hyphantria cunea)、野桑蚕(Bombyx mandarina)以及果蝇(Drosophila melanogaster)Cu/Zn-SOD基因的同源性分别是81.5%、81.7%、81.5%、66.7%。柞蚕蛹经紫外线照射处理后用半定量PCR方法检测,发现照射不同时间脂肪体内Cu/Zn-SOD基因的转录水平存在差异,在照射5 min后开始增加,至10 min时为转录高峰,15 min时又呈下降趋势。  相似文献   
107.
The ability of a set of Photobacterium damselae ssp. piscicida strains isolated from different fish species to produce different superoxide dismutase (SOD) and catalase enzymes was determined. Unlike other bacterial pathogens, P. damselae ssp. piscicida is not able to produce different isoforms of SOD or catalase containing different metal cofactors when cultured under oxidative stress induced by hydrogen peroxide or methyl viologen, or under iron depleted conditions. However, iron content of the growth medium influenced the levels of SOD and catalase activity in cells, these levels decreasing with iron availability of the medium. Comparison of virulent and non-virulent strains of P. damselae ssp. piscicida showed similar contents of SOD, but higher levels of catalase were detected in cells of the virulent strain. Incubation of bacteria with sole, Solea senegalensis (Kaup), phagocytes has shown that survival rates range from 19% to 62%, these rates being higher for the virulent strain. The increased levels of catalase activity detected in the virulent strain indicates a possible role for this enzyme in bacterial survival.  相似文献   
108.
蓖麻蚕滞育与过氧化氢代谢的关系   总被引:1,自引:1,他引:0  
为了探讨蓖麻蚕滞育的机理,研究了蓖麻蚕蛹H2O2代谢的变化,并比较了在5℃冷藏滞育条件下的差异。结果表明,常温环境蓖麻蚕蛹期的H2O2含量呈减少趋势,第3~5天急速变化,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性在第5天出现活性峰,故蛹期第3~5天是蓖麻蚕生理变化的一个敏感时期。第3天开始蛹滞育条件5℃冷藏,雄蛹在30 d前后、雌蛹在80 d左右H2O2含量出现快速改变;SOD和CAT活性一直呈下降趋势,但自30 d开始CAT活性出现快速下降过程,5℃冷藏30 d是蓖麻蚕蛹H2O2代谢的临界期生理时间,这与蚕蛹的30 d冷藏阈值时间吻合。  相似文献   
109.
The experimental diets containing five levels of creatine supplementation, namely control (N = 0 g/kg creatine), B1 (1.00 g/kg glycine), B2 (0.40 g/kg creatine), B3 (0.80 g/kg creatine) and B4 (1.20 g/kg creatine) were tested to red tilapia up to apparent satiation 3 times a day for 56 days. After the feeding trial, fish were stressed by air exposure for challenge test against stress. The results described that creatine supplementation improved final body weight, feed conversion ratio (FCR) and protein retention. Creatine supplementation decreased blood glucose, cholesterol and triglyceride levels (p < .05), indicating more effective usage of non‐protein energy. Furthermore, creatine supplementation also increased plasma insulin levels and upregulated IGF‐1 and GLUT4 gene expressions in the liver significantly; it also improved robustness against stress, which was shown by higher superoxide dismutase, higher postchallenge survival and plasma cortisol, malondialdehyde and lower glucose levels. In conclusion, creatine supplementation at a dose of 0.289–0.389 g/kg diet escalated fish growth and improved robustness against stress via improving the SOD activity in red tilapia.  相似文献   
110.
小兴安岭地区常见蚂蚁营养成分分析   总被引:1,自引:1,他引:0  
为了更好地开发和利用东北林区丰富的蚂蚁资源,提供现实依据和理论基础,笔者对黑龙江省小兴安岭丰林保护区内2种常见蚁种(拟黑多刺蚁、赤蚁)体内营养成分进行分析测定,并对抗氧化物成分进行了比较。结果表明:拟黑多刺蚁与赤蚁均含有丰富的营养成分,粗蛋白质含量超过所有参比的畜禽类及鱼类食品,分别为62.4%、56.6%,经方差分析得知,两者差异性显著(P<0.01);维生素C含量分别为23.0、23.2 mg/g,差异性不显著(F=6.161;P>0.05);超氧化物歧化酶(SOD)含量分别为73.5、42.5 U/mL,SOD在拟黑多刺蚁体内含量比赤蚁体内含量高72.94%;过氧化物酶(POD)含量分别为7.1、4.7 U/mL,POD在拟黑多刺蚁体内含量比赤蚁体内含量高51.06%。因此,拟黑多刺蚁更适合做为蛋白质保健食品进行开发利用,2种蚂蚁体内抗氧化物成分高,可以做药业成分进行开发利用。  相似文献   
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