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1.
When Rhizopus arrhizus NRRL 1526 was mix-cultured with Proteus vulgaris AHU 1144, a strain having a high fumarase activity, in a medium containing glucose as a substrate, fumaric acid fermentation was successively converted to l-malic acid fermentation and large amounts of l-malic acid were accumulated as an end product.As an inoculum of P. vulgaris for this fermentation, cells in the stationary growth phase (48 to 72 hr culture) were much more favorable than those in the exponential growth phase (18 hr culture) and malic acid yields in the former case were as high as about 70 to 75 % based on initial glucose after 3 to 4 days of the mixed culture. 相似文献
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Kuniharu Suzumura Yoshimasa Hashimura Hitoshi Kubota Hiroshi Ohmizu Toshikazu Suzuki 《Free radical research》2013,47(3):255-264
We investigated the antioxidative property of T-0970, a newly synthesized ureidophenol derivative. The inhibitory effect of T-0970 on spontaneous lipid peroxidation in rat brain was 10 times greater than those of well-known antioxidants such as butylhydroxytoluene (BHT), probucol and α-tocopherol. T-0970 also showed dose-dependent free radical scavenging activities in vitro for both superoxide anions and hydroxyl radicals. The radical-scavenging potencies of T-0970 were about 10–30 times stronger than those of BHT. We evaluated the in vivo antioxidative ability of T-0970 in the animal model of acute oxidative tissue injury in rats. Intraperitoneal injection of ferric nitrilotriacetate (Fe/NTA) caused an acute and remarkable increase in the level of thiobarbituric acid-reactive substances (TBARS) in both plasma and the liver, and also resulted in a considerable elevation of the plasma levels of GOT and GPT indicative of hepatic injury. Both oral and intravenous administration of T-0970 dose-dependently depressed these diagnostic parameters. These results indicate that T-0970 may have a therapeutic potential in various diseases associated with oxidative tissue injury. 相似文献
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The effects of hypoxia and paraquat on the superoxide dismutase activity in different organs of carp, Cyprinus carpio L. 总被引:5,自引:0,他引:5
The effects of hypoxia and paraquat (PQ) were investigated on the superoxide dismutase (SOD) activity in carp gill, liver and brain. Increases in SOD activity occurred in these organs following exposure to both PQ and hypoxia. PQ administration under hypoxic conditions significantly increased the SOD activity in the gill as compared to the level in animals in an hypoxic state without PQ treatment. No such change was observed in the liver or brain. 相似文献
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Kim SY Marekov L Bubber P Browne SE Stavrovskaya I Lee J Steinert PM Blass JP Beal MF Gibson GE Cooper AJ 《Neurochemical research》2005,30(10):1245-1255
Transglutaminase activity was found to be present in highly purified non-synaptosomal rat brain mitochondria. A 78-kDa protein
in these organelles was shown to be a transglutaminase 2 substrate, and incubation of a non-synaptosomal mitochondrial lysate
with transglutaminase 2 yielded high-Mr proteins. The 78-kDa protein was identified as mitochondrial aconitase by MALDI-TOF analysis. Aconitase activity was decreased
in a dose-dependent manner when non-synaptosomal rat brain mitochondria were incubated with transglutaminase 2. Transglutaminase
activity is increased about 2-fold in the mitochondrial fraction of HD caudate. Moreover, Western blotting of the mitochondrial
fraction revealed that most of the mitochondrial aconitase in HD caudate is present as high-Mr aggregates. Aconitase activity was previously shown to be decreased in Huntington disease (HD) caudate (a region severely
damaged by the disease). The present findings suggest that an increase of transglutaminase activity in HD caudate may contribute
to mitochondrial dysfunction by incorporating aconitase into inactive polymers. 相似文献
5.
Leo I. Gordon David Weiss Sheila Prachand Sigmund A. Weitzman 《Free radical research》1991,15(1):65-71
On the basis of previous observations, we attempted to characterize the effects of various products of phospholipid hydrolysis on neutrophil (PMN) respiratory burst activity. We studied the effects of phos- phorylcholine (PC) and phosphorylethanoline (PE) on superoxide anion production in PMN and in a cell free system. We found that PE but not PC inhibited measured superoxide anion, but that this was not due to inhibition of cellular superoxide generation but to scavenging of generated superoxide anion. Further, utilizing a system based upon the photo-oxidation of O-dianisidine sensitized by riboflavin, we were able to determine that the scavenging effect of PE was not superoxide dismutase (SOD)-like but rather a general scavenging or glutathione (GSH)-like effect. These data underscore the importance of identifying the mechanism of inhibition of superoxide generation by putative inhibitors as being due to a direct cellular effect or to a scavenging property. 相似文献
6.
Excessive production of reactive oxygen species (ROS) is a key phenomenon in tumor necrosis factor (TNF)-α-induced cell death. However, the role of ROS in necroptosis remains mostly elusive. In this study, we show that TNF-α induces the mitochondrial accumulation of superoxide anions, not H2O2, in cancer cells undergoing necroptosis. TNF-α-induced mitochondrial superoxide anions production is strictly RIP3 expression-dependent. Unexpectedly, TNF-α stimulates NADPH oxidase (NOX), not mitochondrial energy metabolism, to activate superoxide production in the RIP3-positive cancer cells. In parallel, mitochondrial superoxide-metabolizing enzymes, such as manganese-superoxide dismutase (SOD2) and peroxiredoxin III, are not involved in the superoxide accumulation. Mitochondrial-targeted superoxide scavengers and a NOX inhibitor eliminate the accumulated superoxide without affecting TNF-α-induced necroptosis. Therefore, our study provides the first evidence that mitochondrial superoxide accumulation is a consequence of necroptosis. 相似文献
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Irena Kruk Teresa Michalska Aleksandra Kładna Paweł Berczyński Hassan Y. Aboul‐Enein 《Luminescence》2011,26(6):598-603
A chemiluminescent technique was applied to determine antioxidative activities of adriamycin, farmorubicin, mitomycin C and bleomycin against superoxide anion radical (O2?) in aprotic medium. The antioxidant capacity was expressed as the decrease in light emission from the O2? solution by and antibiotic. A KO2 solution in dimethyl sulphoxide (DMSO) and 18‐crown‐6 ether were used for the generation of O2?. The results showed that the examined compounds decreased the chemiluminescence (CL) sum from the O2?‐generating system in a dose‐dependent manner. Among the antibiotics examined, adriamycin, farmorubicin and bleomycin exhibited antioxidant activity almost comparable to that of 1,2‐dihydroxy benzene‐3,5‐disulphonic acid (tiron), an efficient of the O2? inhibitor. Mitomycin C was two‐times less effective as tiron in decreasing the initial CL intensity. The proposed assay with usage of ultraweak CL technique and the KO2–DMSO–crown ether system was useful for the evaluation of antioxidant activity in aprotic solvents. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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We examined the possibility that the peroxidative damage to central nervous system myelin produced by reactive oxygen species (ROS), could modify the susceptibility of its proteins to the proteolytic action of proteases such as trypsin and subtilisin. Purified myelin membranes obtained from adult rat brains were in vitro peroxidized by two non-enzymatic systems: Fe3+ plus ascorbic acid and Cu2+ plus hydrogen peroxide. Myelin proteins were severely affected by peroxidation. There was an increase in the amount of carbonyl groups (CO), accompanied by and enhanced susceptibility to degradation by trypsin and subtilisin of myelin basic proteins (MBP) and of the major proteolipid protein (PLP). The effect upon the degradation of myelin protein is a possible consequence of the appearance in the structure of myelin proteins of peroxidative modifications that contribute to the recognition by proteolytic enzymes. This hypothesis is supported by the fact that if peroxidation of myelin membranes is done in the presence of EDTA, both CO formation and increased sensitivity to enzymatic breakdown disappear. These results suggest that the appearance of abnormal post-translational modifications in the myelin membrane produced by peroxidation could constitute a putative mechanism of modulating the capacity of myelin proteins to be metabolized by proteases. 相似文献
11.
《Free radical research》2013,47(1):195-204
Oxygen free radicals are the final or intermediate products of many metabolic reactions. Of greatest significance to the organism are superoxide anion radical (O2-), hydrogen peroxide (H2O2), hydroxyl radical (OH). singlet oxygen (lO2) etc. A proper ratio between both production and breakdown of oxy-radicals is essential for the maintenance of a dynamic equilibrium of vital processes. The superoxide dismutases protect cells against toxic influence of the superoxide. In addition, some square-pyramidally pentacoordinated copper(II) complexes, derived from tridentate Schiff bases of the N-salicylideneaminoal-canoate type, show remarkable SOD-like activity. A selected set of complexes of this type have been tested: potassium [aqua-(N-salicylideneglutamato) cuprate] (L-and D,L-form). potassium [(isothiocyanato)-(N-salicylideneglycinato) cuprate], potassium [(isothiocyanato)-(N-salicylidene-D,L-alaninato) cuprate]. potassium ((isothiocyanato)-(N-salicylidene-β-alaninato) cuprate] and potassium [(isocyanate)-(N-salicylideneglycinato) cuprate]. Our results suggest that the copper complexes are not only antioxidants, but may also possess anti-inflammatory, cytostatic and radioprotective properties. 相似文献
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Data on the structure, functions, regulation of activity, and expression of cytosolic and mitochondrial aconitate hydratase isoenzymes of mammals are reviewed. The role of aconitate hydratase and structurally similar iron-regulatory protein in maintenance of homeostasis of cell iron is described. Information on modifications of the aconitate hydratase molecule and changes in expression under oxidative stress is generalized. The role of aconitate hydratase in the pathogenesis of some diseases is considered. 相似文献
13.
Süreyya Ölgen PInar Varol Tülay Çoban Doğu Nebioğlu 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):334-340
The in vitro antioxidant effects of novel N-substituted indole-3-carboxamides (I3CDs) 1-10 on rat liver microsomal NADPH-dependent lipid peroxidation (LP) levels and their free radicals scavenging properties were determined by the inhibition of superoxide anion formation (SOD). Among the synthesized compounds, 4, 5, 8 and 9 significantly inhibited SOD with an inhibition range at 84–100% at 10? 3 M concentration. The presence of halo substituents both ortho- and para- positions of these compounds resulted 100% inhibition of SOD. Comparison the activity results of halogenated and non-halogenated derivatives suggested that the halogenated compounds are more active than the non-halogenated compounds. On the other hand, the introduction of a para fluoro benzyl in the 1-position of indole (compounds 7, 8) has more impact on the SOD inhibition when the benzamide ring was mono halogenated. However, none of other compounds had a significant inhibitory effects on the level of lipid peroxidation. 相似文献
14.
The generation of free radicals in a superoxide (O2-)driven Fe+3 catalysed reactions with isolated myocytic sarcolemma using electron spin resonance was investigated. Incubation of highly purified canine myocytic sarcolemma in the presence of the spin trap, 2-methyl-2-nitrosopropane (MNP). followed by the addition of dihydroxyfurmarate (DHF) and Fe+3-ADP resulted in the generation and detection of radical adducts of this spin trap. Spin trapping of the alkyl radicals with 2-methyl-2-nitrosopropane led to the identification of methyl radical adduct following exposure to DHF/Fe+3-ADP. With sarcolemma and the alkyl nitroso compound, the only radical product trapped was the methyl radical formed by β-scission of alkoxyl radical. The participation of hydroperoxide-derived radicals in this system verified that the decomposition of unsaturated hydroperoxy fatty acid does proceed via a free radical mechanism. 相似文献
15.
The concentration of the endogenous neurotoxin quinolinic acid (QA) is increased in the central nervous system of mice with herpes simplex encephalitis. We have previously shown that the antiherpetic agent acyclovir (AC) has the ability to reduce QA-induced neuronal damage in rat brain, by attenuating lipid peroxidation. The mechanism by which QA induces lipid peroxidation includes the enhancement of the iron (Fe)-mediated Fenton reaction and the generation of free radicals, such as the superoxide anion (O(2)(-)). Thus, the present study determined whether AC has the ability to reduce Fe(2+)-induced lipid peroxidation, O(2)(-) generation and QA-induced superoxide anion generation, and to bind free Fe. O(2)(-) and Fe(2+) are also cofactors of the enzymes, indoleamine-2,3-dioxygenase (IDO) and 3-hydroxyanthranilate-3,4-dioxygenase (3-HAO) respectively. These enzymes catalyse steps in the biosynthesis of QA; thus, the effect of AC on their activity was also investigated. AC significantly attenuates Fe(2+)-induced lipid peroxidation and O(2)(-) generation. AC reduces O(2)(-) generation in the presence of QA and strongly binds Fe(2+) and Fe(3+). It also reduces the activity of both IDO and 3-HAO, which could be attributed to the superoxide anion scavenging and iron binding properties, respectively, of this drug. 相似文献
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Junko Adachi Masafumi Tomita Sachiko Yamakawa Migiwa Asano Takeaki Naito Yasuhiro Ueno 《Free radical research》2013,47(3):321-327
The in vivo paraquat-induced oxidative stress in rat tissue was studied by analyzing cholesterol-derived hydroperoxide as an index of lipid peroxidation. Paraquat (10 mg/kg) was administered i.p. to rats. Rats were sacrificed and lung, liver, and kidney were collected 2, 24 h, and 5 d after paraquat injection. Lipids were extracted and analyzed by HPLC with post-column chemiluminescence. We found that two cholesterol-derived hydroperoxides, 7α-hydroperoxycholest-5-en-3β-ol (7α-OOH) and 7β-hydroperoxycholest-5-en-3β-ol (7β-OOH) were present in lungs of control animals (0.06 and 0.06 nmol/g, respectively), in livers (6.5 and 15.8 nmol/g, respectively) and in kidneys (3.7 and 8.9 nmol/g, respectively). In liver paraquat increased lipid peroxidation approximately by 60% over the levels of control animals only at 2 h after paraquat treatment. In kidney, augmented lipid peroxidation, 7α-OOH and 7β-OOH (by 70% and 147%, respectively) above levels was found at 2 h after paraquat treatment. Interestingly, these increase remained in kidney of rats 5 d after a single dose of paraquat. In contrast, cholesterol-derived hydroperoxides were not affected in lung of paraquat dosed rats. This is the first report on 7α-OOH and 7β-OOH accumulations in rat liver and kidney, and it seems to reflect greater oxidative stress in the pathology of kidney of rats treated with acute paraquat at low dose. 相似文献
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《Free radical research》2013,47(6-7):463-473
AbstractFerritin (Ft) impairment through ?O2–, H2O2, and ?OH production occurs in the cases of ketoses, diabetes mellitus, acute intermittent porphyria and tyrosinemia. In addition to ?Trp and TyrO? radical production, ferrous iron liberation and Ft synthesis stimulation, site-specific oxidation reactions are induced leading to toxic iron accumulation in organs with high Ft content, for example, liver and brain. To elucidate the potential pathways to Ft recovery, repair of oxidative damage to horse spleen apoferritin (apoFt) and Ft by quercetin (QH) or rutin (RH) was studied in the presence and absence of oxygen. ?Trp and TyrO? radicals were produced in pulse radiolysis through apoFt oxidation by ?Br2– radicals. QH and RH bind to apoFt on eight sites with binding constants of ?80,000 and ?32,000 M?1, respectively. In deaerated solutions, a repair of apoFt radicals is observed involving both bound and free flavonoids. This repair occurs by a fast intra- and a slow inter-molecular electron transfer from bound and free flavonoids, respectively. With QH, the rate constants are 104 s–1 and 3.5 × 107 M–1 s–1 for the intra- and intermolecular repair reactions, respectively. Oxygen does not interfere with repair of apoFt or Ft by bound QH but inhibits 90% of Ft repair by RH. These results taken together indicate that flavonoid antioxidants may help alleviate Ft impairment in diseases involving an oxidative stress. 相似文献