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The dietary effect of vitamin E supplementation on fingerlings of Labeo rohita during refrigerated storage was investigated. Six graded levels of vitamin E, between 0-125 mg/kg vitamin E, were fed to fish. After 60-day feeding trial, fish were sacrificed, fillets were stored in refrigerator at -20°C and analyzed on 0, 15 and 30th day of storage. Upon refrigeration the vitamin E fed fish showed reduced level of Thiobarbituric acid reactive substances (TBARS) at all storage days. The enzyme activities were improved by elevating the levels of vitamin E in diet as well as by storage period (P < 0.05) for all treatments. Fatty acid profile indicated that n-3, n-6 fatty acids and the ratios of ARA/EPA and n-3/n-6 were increased by increasing vitamin E supplementation and decreased with an increase in the storage period. Conclusively, the dietary vitamin E reduced lipid peroxidation and improved the fillet quality of stored fish. [ABSTRACT FROM AUTHOR]

A synthesis of two series of homoleptic phenolate complexes with fluorinated aryloxide ligands A2[M(OAr)4] with M = Co(super 2+) or Cu(super 2+), OAr(super -) = (OC6F5)(super -) (OAr(super F)) or {3,5-OC6H3(CF3)2}(super -) (OAr'), A(super +) = K (18-crown-6)(super +), Tl(super +), Ph4P(super +), Et3HN(super +), or Me4N(super +) was conducted.

Two series of homoleptic phenolate complexes with fluorinated aryloxide ligands A2[M(OAr)4] with M = Co2+ or Cu2+ OAr- = (OC6F5)- (OArF) or &lcub;3,5-OC6H3(CF3)2&rcub;- (OAr′), A+ = K (18-crown-6)+, Tl+, Ph4P+, Et3HN+, or Me4N+ have been synthesized. Two related complexes with nonfluorinated phenoxide ligands have been synthesized and studied in comparison to the fluorinated aryloxides demonstrating the dramatic structural changes effected by modification of OPh to OArF. The compounds &lcub;K(18-crown-6)&rcub;2[Cu(OArF)4], 1a; &lcub;K(18-crown-6)&rcub;2[Cu(OAr′)4], 1b; [Tl2Cu(OArF)4], 2a; [Tl2Cu(OAr′)4], 2b; (Ph4P)2[Cu(OArF)4], 3; (nBu4N)2[Cu(OArF)4], 4; (HEt3N)2[Cu(OArF)4], 5; &lcub;K(18-crown-6) &rcub;2[Cu2(μ2-OC6H5)2(OC6H5)4], 6; &lcub;K(18-crown-6) &rcub;2[Co(OArF)4], 7a; &lcub;K(18-crown-6) &rcub;2[Co(OAr′)4], 7b; [Tl2Co(OArF)4], 8a; [Tl2Co(OAr′)4], 8b; (Me4N)2[Co(OArF)4], 9; [Cp2Co]2[Co(OAr′)4], 10; and &lcub;K(18-crown-6) &rcub;2[Co2(μ2-OC6H5)2(OC6H5)4], 11, have been characterized with UV-vis and multinuclear NMR spectroscopy and solution magnetic moment studies. Cyclic voltammetry was used to study 1a, 1b, 7a, and 7b. X-ray crystallography was used to characterize 1b, 3, 4, 5, 6, 7a, 7b, 10, and 11. The related [MX4]2 compound (Ph4P)2[Co(OArF)2Cl2], 12, has also been synthesized and characterized spectroscopically, as well as with conductivity and single-crystal X-ray diffraction. Use of fluorinated aryloxides permits synthesis and isolation of the mononuclear, homoleptic phenolate anions in good yield without oligomerized side products. The reaction conditions that result in homoleptic la and 7a with OArF upon changing the ligand to OPh result in μ2-OPh bridging phenoxides and the dimeric complexes 6 and 11. The [M(OArF)4]2 and [M(OAr′)4]2- anions in 1a, 1b, 3, 4, 5, 7a, 7b, 9, and 10 demonstrate that stable, isolable homoleptic phenolate anions do not need to be coordinatively or sterically saturated and can be achieved by increasing the electronegativity of the ligand. [ABSTRACT FROM AUTHOR]