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121.
Yu-Chia Chang Liang-Mou Kuo Tsong-Long Hwang Jessica Yeh Zhi-Hong Wen Lee-Shing Fang Yang-Chang Wu Chan-Shing Lin Jyh-Horng Sheu Ping-Jyun Sung 《Marine drugs》2016,14(1)
Three new 9,11-secosterols, pinnisterols A–C (1–3), were isolated from a gorgonian coral Pinnigorgia sp., collected off the waters of Taiwan. The structures of these compounds were elucidated on the basis of spectroscopic methods. The new sterols 1 and 3 displayed significant inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils, and sterol 1 was found to show moderate cytotoxicity in hepatic stellate cells (HSCs). 相似文献
122.
[目的]测定不同油茶品种健康叶片中的3种保护酶活性,为油茶抗病性、抗逆性机理研究提供参考依据.[方法]采用紫外—可见分光光度计法,测定岑软3号油茶、博白大果油茶、普通油茶、岑软2号油茶、香花油茶和陆川油茶6个油茶品种叶片的过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性.[结果]6个品种油茶叶片的POD活性排序为普通油茶>(博白大果油茶和岑软3号油茶)>(岑软2号油茶、香花油茶和陆川油茶),CAT活性排序为岑软3号油茶>(普通油茶、博白大果油茶和岑软2号油茶)>(香花油茶和陆川油茶),SOD活性排序为陆川油茶>岑软3号油茶>(博白大果油茶、普通油茶、岑软2号油茶和香花油茶).[结论]以油茶健康叶片中POD、CAT和SOD活性高低可判断油茶的抗病性或抗逆性强弱. 相似文献
123.
以台湾玉华苦瓜(Momordica charantia L.)为试材,研究淹水时间对苦瓜幼苗生长、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性的影响。结果表明,淹水4 d时,玉华苦瓜幼苗的各项指标与对照差异不显著;淹水8 d后,株高显著低于对照,MDA含量、SOD活性显著高于对照;淹水12 d后,株高、叶片数显著低于对照,MDA含量、SOD活性显著高于对照。说明玉华苦瓜对涝渍胁迫的抵抗能力有限,生理受到伤害,生长受到抑制。 相似文献
124.
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
125.
Maryam Haghighi 《Journal of plant nutrition》2016,39(5):655-665
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
126.
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
127.
Helena M. Amaro Fátima Fernandes Patrícia Valent?o Paula B. Andrade I. Sousa-Pinto F. Xavier Malcata A. Catarina Guedes 《Marine drugs》2015,13(10):6453-6471
Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components—especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+•)) and biological reactive species (O2•− and •NO−). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH• and ABTS+•, respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O2•−, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in •NO− assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance—which appears to hinge, in particular, on the balance between carotenoids and PUFAs. 相似文献
128.
Overproduction of reactive oxygen species involved in the pathogenicity of Fusarium in potato tubers
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 () 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
129.
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
130.
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