The objective of this study was to determine phytochemical characteristics, chemiluminescence antioxidant capacities, and neuroprotective effects on PC12 cells for methanol extracts of Spatholobus suberectus, Uncaria rhynchophylla, Alpinia officinarum, Drynaria fortunei, and Crataegus pinnatifida. The C. pinnatifida extract (CPE) afforded the greatest yield and total phenolic content. The S. su...

Abstract Coumarin and its nitrogen analogue 1-aza coumarin are a class of lactones lactams, respectively, which indispensable heterocyclic units to both chemists biochemists. 1-Aza derivatives, ultimately metabolize as the corresponding 8-hydroxy coumarins in biological system therefore found be very good anti-inflammatory, anti-cancer, analgesic agents. A series hybrid substituted azacoumarin-...

The freezing and thawing process not only is associated with serious damage to sperm such as damage to the plasma membrane and the acrosomal membrane but also changes the membrane permeability to some ions including calcium. Also, the generation of oxygen free radicals is increased during the freezing-thawing process. The purpose of this study was to evaluate of the effects of Trolox as an anti...

The yeast Trichosporon mucoides, grown on either glucose or phenol, was able to transform biphenyl into a variety of mono-, di-, and trihydroxylated derivatives hydroxylated on one or both aromatic rings. While some of these products accumulated in the supernatant as dead end products, the ortho-substituted dihydroxylated biphenyls were substrates for further oxidation and ring fission. These r...

Background: The mechanism of hypoxic pulmonary vasoconstriction (HPV) is still debatable. It has been proposed that reactive oxygen species (ROS) might be involved in HPV. However, there is no special transporter for superoxide anion in the cell membrane and it may release from the cells via anion exchanger. Therefore, the aim of this study was to investigate the interaction of ROS and anion ex...

N itronate com pounds resembling the aa-carboxylate reaction interm ediate in the reaction catalyzed by isopropylm alate isomerase were investigated as enzyme inhibitors and potential herbicides. The nitronic acids o f l-hydroxy-2-nitrocyclopentane-l-carboxylic acid, nitroisop ropylm alate and o f l-hydroxy-2-nitrocyclohexane-l-carboxylic acid were all po ten t inhibi­ tors o f isopropylm alate...

Six new furan derivatives, named 5-(3-methoxy-3-oxopropyl)-furan-2-carboxylic acid (1), 1-(5-(2-hydroxypropanoyl)-furan-2-yl)-pentan-3-one (2), 2-hydroxy-1-(5-(1-hydroxypentyl)-furan-2-yl)-propan-1-one (3), 1-(5-(1,2-dihydroxypropyl)-furan-2-yl)-pentan-1-one (4), 5-(1-hydroxypent-4-en-1-yl)-furan-2-carboxylic acid (5) and 5-(3-hydroxypentyl)-furan-2-carboxylic acid (6), together with two new na...

18O labeling studies on the catechol 1,2-dioxygenase-catalyzed oxidative cleavage of pyrogallol demonstrate that the enzyme functions both as a dioxygenase and a monooxygenase in this reaction. Two products are observed, 2-pyrone-6-carboxylic acid, 99% singly labeled at the carboxylate, and 2-hydroxy-cis,cis-muconic acid, 74% doubly labeled (one 18O at each carboxylate) and 24% single labeled (...

Although arsenic trioxide (As(2)O(3)) is an effective therapy in acute promyelocytic leukemia (APL), its use in other malignancies is limited by the toxicity of concentrations required to induce apoptosis in non-APL tumor cells. We looked for agents that would synergize with As(2)O(3) to induce apoptosis in malignant cells, but not in normal cells. We found that trolox (6-hydroxy-2,5,7,8-tetram...

Studies have shown increased oxidative stress in patients with chronic airflow limitation; however, the population-based evidence for the association of oxidative stress with pulmonary function is limited. The authors analyzed the association of plasma thiobarbituric acid-reactive substances (TBARS), glutathione, glutathione peroxidase, and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid...