Electron Paramagnetic Resonance Study of the Free Radical Scavenging Capacity of Curcumin and Its Demethoxy and Hydrogenated Derivatives.

The quantitative free radical scavenging capacity of curcumin and its demethoxy derivatives (demethoxycurcumin (Dmc) and bisdemethoxycurcumin (Bdmc)) and hydrogenated derivatives (tetrahydrocurcumin (THC), hexahydrocurcumin (HHC) and octahydrocurcumin (OHC)) towards 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide radical (NO), hydroxyl radical (HO(·)) and superoxide anion radical (O2(·)) were investigated by electron paramagnetic resonance (EPR) spectroscopy. One mole of the hydrogenated derivatives scavenged about 4 mol of the DPPH radical, while curcumin and Dmc scavenged about 3 mol of the DPPH radical. Curcumin and THC showed moderate scavenging activity towards NO, yielding 200 mmol of NO scavenged per 1 mol of the scavenger.

Characterisation of a novel oral iron chelator: 1-(N-Acetyl-6-Aminohexyl)-3-Hydroxy-2-Methylpyridin-4-one.

Objectives: Desferrioxamine (DFO), deferiprone (DFP) and deferasirox (DFX) are iron chelators currently in clinical use for the treatment of iron overload. Due to difficulties with administration and associated side effects with these three molecules, the search continues for an efficient nontoxic orally active iron chelator. This communication describes the properties of one such candidate, 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1).

Effect of a novel oral active iron chelator: 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1) in iron-overloaded and non-overloaded mice.

Objective: To evaluate efficacy and toxicity of a novel orally active bidentate iron chelator, 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1) in mice under normal and iron overload conditions.

Methods: Wild type C57BL/6 mice were fed with normal and 0.2% (w/w) ferrocene-supplemented (Fe) diets, respectively for 240 d and orally given the CM1 (50, 100 and 200 mg/kg) for 180 d.

Iron-chelating and anti-lipid peroxidation properties of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1) in long-term iron loading β-thalassemic mice.

Objective: To evaluate the iron-chelating properties and free-radical scavenging activities of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1) treatment in chronic iron-loaded β-thalassemic (BKO) mice.

Methods: The BKO mice were fed with a ferrocene-rich diet and were orally administered with CM1 [50 mg/(kg.day)] for 6 months.

Curcumin extract for prevention of type 2 diabetes.

Objective: To assess the efficacy of curcumin in delaying development of type 2 diabetes mellitus (T2DM) in the prediabetic population.

Research Design And Methods: This randomized, double-blinded, placebo- controlled trial included subjects (n = 240) with criteria of prediabetes. All subjects were randomly assigned to receive either curcumin or placebo capsules for 9 months.

Tetrahydrocurcumin alleviates hypertension, aortic stiffening and oxidative stress in rats with nitric oxide deficiency.

Tetrahydrocurcumin (THC), a major metabolite of curcumin, possesses strong antioxidant and cardioprotective properties. However, the activities of THC in hypertension and its associated complications remain unknown. The aim of this study was to investigate the effect of THC on hemodynamic status, aortic elasticity and oxidative stress in rats with N-nitro-L-arginine methyl ester (L-NAME)-induced hypertension.

Antioxidant and vascular protective effects of curcumin and tetrahydrocurcumin in rats with L-NAME-induced hypertension.

Inhibition of nitric oxide synthesis with N ( ω )-nitro-L-arginine methyl ester (L-NAME) induces marked hypertension and oxidative stress. Curcumin (CUR) has been shown strong antioxidant property. Tetrahydrocurcumin (THU), a major metabolite of CUR, possesses several pharmacological effects similar to CUR; however, it is less studied than CUR.

Improvement in oxidative stress and antioxidant parameters in beta-thalassemia/Hb E patients treated with curcuminoids.

Objectives: To evaluate the hematological profile, oxidative stress, and antioxidant parameters in beta-thalassemia/Hb E patients treated with curcuminoids for 12 months.

Design And Methods: Twenty-one beta-thalassemia/Hb E patients were given 2 capsules of 250 mg each of curcuminoids (a total of 500 mg) daily for 12 months. Blood was collected every 2 months during treatment and 3 months after withdrawal and was determined for complete blood count, malonyldialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) in red blood cells (RBC), and non-transferrin bound iron (NTBI) in serum.

Ultrasound-assisted extraction of capsaicinoids from Capsicum frutescens on a lab- and pilot-plant scale.

The influence of operating parameters (solvent type, powder to solvent ratio and temperature) on the ultrasonically assisted extraction of capsaicinoids from dried Capsicum frutescens (fruit) was studied. From the economic perspective, the suitable condition for capsaicinoid extraction by indirect sonication in an ultrasonic bath with a working frequency of 35 kHz was at a ratio of 1g of solid material: 5 ml of 95% (v/v) ethanol, 45 degrees C, where 85% of the capsaicinoids were removed from the raw material in 3h. In an experimental pilot study in 20-l extraction tank at the fixed ultrasonic frequency of 26 kHz and 70 kHz, the recovery of capsaicinoids was 76% and 70%, respectively.

Comparative antioxidant activities of curcumin and its demethoxy and hydrogenated derivatives.

The antioxidant activities of curcumin, its natural demethoxy derivatives (demethoxycurcumin, Dmc and bisdemethoxycurcumin, Bdmc) and metabolite hydrogenated derivatives (tetrahydrocurcumin, THC; hexahydrocurcumin, HHC; octahydrocurcumin; OHC) were comparatively studied using 2,2-diphenyl-1-picrylhydrazyl (DDPH) radical, 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) induced linoleic oxidation and AAPH induced red blood cell hemolysis assays. Hydrogenated derivatives of curcumin exhibited stronger DPPH scavenging activity compared to curcumin and a reference antioxidant, trolox. The scavenging activity significantly decreased in the order THC>HHC=OHC>trolox>curcumin>Dmc>>>Bdmc.