seven stilbenes and one catechin were bioactivity-guidedly isolated from the rhizomes of rheum palmatem. their structures were identified as piceatannol(1), resveratrol(2), piceid(3), rhapontigenin(4), piceatannol-3'-o-β-d-glucopyranoside(5), rhaponticin(6), catechin(7) and desoxyrhapontigenin(8). anti-monoamine oxidase (mao) activities of compounds 1–8 were tested. compounds 1 and 8 showe...

to develop a new more accurate spectrophotometric method for detecting monoamine oxidase inhibitors from plant extracts, a series of amine substrates were selected and their ability to be oxidized by monoamine oxidase was evaluated by the hplc method and a new substrate was used to develop a peroxidase-linked spectrophotometric assay. 4-(trifluoromethyl) benzylamine (11) was proved to be an exc...

OBJECTIVES This study was designed to investigate whether nicotinamide adenine dinucleotide 3-phosphate (reduced form) (NADPH) oxidase is expressed in the human heart and whether it contributes to reactive oxygen species (ROS) production in heart failure. BACKGROUND A phagocyte-type NADPH oxidase complex is a major source of ROS in the vasculature and is implicated in the pathophysiology of h...

Biowaste derived porous 2D carbon as sustainable, rapid, and efficient oxidase mimic for ascorbic acid (A.A.) detection.

Enzymatic oxidation of apocynin, which may mimic in vivo metabolism, affords a large number of oligomers (apocynin oxidation products, AOP) that inhibit vascular NADPH oxidase. In vitro studies of NADPH oxidase activity were performed to identify active inhibitors, resulting in a trimer hydroxylated quinone (IIIHyQ) that inhibited NADPH oxidase with an IC(50)=31nM. Apocynin itself possessed min...

Objectives. Using apocynin (inhibitor of NADPH oxidase), and Mitoquinol 10 nitrate (MitoQ; mitochondrial-targeted antioxidant), we addressed the importance of mitochondria versus NADPH oxidase-derived ROS in glucose-induced apoptosis of pericytes. Methods. NADPH oxidase was localised using Western blot analysis and cytochrome C reduction assay. Apoptosis was detected by measuring caspase-3 acti...

A fundamental requirement for cellular vitality is the maintenance of plasma ion concentration within strict ranges. It is the function of the kidney to match urinary excretion of ions with daily ion intake and nonrenal losses to maintain a stable ionic milieu. NADPH oxidase is a source of reactive oxygen species (ROS) within many cell types, including the transporting renal epithelia. The focu...

That flavonoids inhibit xanthine oxidase from cow milk was confirmed by measuring oxygen consumption with an oxygen electrode. In contrast, flavonoids did not inhibit glucose oxidase, another oxygen consuming enzyme. Among the flavonoids tested, quercetin, kaempferol, myricetin, chrysin, quercitrin, and morin were potent inhibitors of xanthine oxidase; their inhibition rates (%) were 80, 70, 69...