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Blueberry is one of the fruits that has high antioxidant activity grown in our country. Blueberry is also used for wine making. In this study we investigated alcohol amount, total acidity, reducing sugar, total phenolic content and anthocyanine changes as weekly periods during fermentation in blueberry wine produced by the classical maceration method. It is also performed some antioxidant tests; 2,2-diphenyl-1-dipicrylhydrazyl DPPH radical scavenging activity and reducing power in the final product. Alcohol amount is determined as 12% for final product. Total acidity amount of wine decreased from 11.6 g L-1 to 8.7 g L-1during fermentation and anthocyanine content decreased to 15 mg L-1. Total phenolic content is measured as 199.49 mg L-1. % DPPH Radical scavenging activity and reducing power was found as 52.5% and 0.170, respectively. [ABSTRACT FROM AUTHOR]

Reaction of VOSO4with 2-hydroxy-napthaldeyde-S-R-thiosemicarbazones (R: methyl, ethyl, propyl or allyl) and salicyl aldehyde yielded five-coordinate oxovanadium(IV) complexes having a N1,N4-diarylidene-S-R-thiosemicarbazidato structures. The compounds were characterized by elemental analysis, magnetic measurements, electronic, infrared,1H-NMR, and electron paramagnetic resonance (EPR) spectra. The X-band EPR signals were recorded from powder forms and also in solution. All the complexes have a single asymmetric line shape and theoretical fit studies prove the presence of axial symmetry around the paramagnetic vanadium ions. A computer simulation of the EPR spectrum of each complex was carried out to derive the related EPR parameters. Cyclicvoltammogramsof the complexes exhibited two metal-based reversible redox peaks around 500 and −800 mV corresponding to one electron oxidation/reduction of VIVO/VVO and VIVO/VIIIO, respectively. The reductive response in the 50–350 mV region was assigned to ligand reduction. Antioxidant activities of the compounds were determined with CUPric Reducing Antioxidant Capacity, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid, and 1,1-diphenyl-2-picrylhydrazyl assays. The test results indicated that the antioxidant capacity of the compounds increases with the carbon number of saturated hydrocarbon chain on sulfur atom. [ABSTRACT FROM PUBLISHER]

Extract from leaves of Carthamus tinctorius L. was prepared by using soxhlet extraction method. Total phenolic, flavonoid content and also antioxidant activity of leaves from Carthamus tinctorius L. were determined. To determine the antioxidant capacity, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH?) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.+) radical scavenging tests were used. Reducing power of the extract was also tested. Total phenolic and flavonoid content of the extract were determined as 77.38 ± 6.62 mg GAE/g, 25.49 ± 0.26 mg CE/g dry weight of extract respectively. DPPH radical scavenging activity was determined as 89%. ABTS radical scavenging activity was found as 58% at 1 mg/mL concentration. Reducing power was found as 0.885. [ABSTRACT FROM AUTHOR]

5-Chloro-4-methyl-2-hydroxybenzophenone S-propyl-4-phenyl-thiosemicarbazone (H 2 L) and its cis -dioxomolybdenum(VI) complexes, in the general formula [MoO 2 (L)R-OH)] (R: methyl, 1 ; ethyl, 2 ; n -propyl, 3 ; n -butyl, 4 ; n -pentyl, 5 ), were synthesized and characterized by micro analysis, electronic, infrared and 1 H and 13 C NMR spectra. The crystal structures of complexes, 1 and 3 , have been solved by direct methods (SIR92) and refined to the residual indexes R 1 = 0.098 and R 1 = 0.052 respectively. Complexes 1 and 3 are crystallized in the triclinic space group P −1 with Z = 2. The crystal study of complex 1 showed the first example of intermolecular hydrogen bond for this type of molybdenum–thiosemicarbazone complexes. The hydrogen bond is between the hydroxyl proton of attached alcohol and an oxo oxygen (in MoO 2 2+ unit) of another complex molecule, and its bond distance (1.767(1) Å) is shorter than from the σ -coordination bonds in complex 1 . Antioxidant activities of the compounds were determined by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Ligand showed 23.61% DPPH radical scavenging activity at 250 mg/L concentration. Cupric Reducing Antioxidant Capacity (CUPRAC) was also evaluated and trolox-equivalent antioxidant capacity (TEAC) values were found for ligand, 1 and 3 as 0.51, 0.33 and 0.30 respectively. [ABSTRACT FROM AUTHOR]