Antioxidant activity of 2,6-dimethyl-3,5-dialkoxycarbonyl-1,4-dihydropyridines in metal-ion catalyzed lipid peroxidation

Abstract

The 1,4-dihydropyridine (I, 1,4-DHP) derivatives, especially compounds unsubstituted in position 4 (I, R'=H), show AOA in homogenous lipid systems (TIRZITIS et al. 1988;ABDALLA et al. 1999). IThe 2,6-dimethyl-3,5-diethoxycarbonyl-1,4-DHP (trade name Diludin) possesses considerable AOA in the stabilization of edible oils (KOUØIMSKÁ et al. 1993) and exhibits synergistic properties with antioxidants, such as α-tocopherol (TIRZITIS et al. 1983) and 2,6-bis(tert-butyl)-4-hydroxytoluene (BHT) (TIRZITIS & KIRULE 1999). Unfortunately the insufficient solubility of Diludin in lipids limits its practical application. This limitation demanded the synthesis and investigation of more lipophilic Diludin homologues.Most foods differ from refined oils and fats in that they are oil-in-water emulsions, where the aqueous phase contains hydrated proteins and carbohydrates (including dietary fibre), and on the other hand, also trace metals that catalyze oxidation. The 1,4-DHP has been less investigated in transition valence metal-ion catalyzed peroxidation. The aim of our study was to investigate the relationship between AOA and alkyl substituent (R) length in of increasing lipophilicity ranging from C 1 (methyl) to C 16 (hexadecyl) in the ester moiety of 1,4-DHP. This would help to choose the best compound for fat, oil and another lipid containing product stabilization studies.We used metal-ion (ferrous and copper) catalyzed phospholipid liposome peroxidation. Liposomes belong to very important lipid systems, present in most foods. The AOA of tested I was compared with AOA of Probucol™ and Trolox™, which belong to relatively polar antioxidants. The study of incorporation of 1,4-DHP into phosphatidylcholine liposomes was carried out as well. The results could be useful for the stabilization of non-homogenous lipid products (margarines, salad dressings, creams, etc.). Antioxidants with 1,4-dihydropyridine structure were investigated as a less harmful alternative to synthetic phenolic antioxidants in liposomes under conditions simulating food storage. The antioxidant activities (AOA) of 2,6-dimethyl-3,5-dialkoxycarbonyl-1,4-dihydropyridines possessing various side chain length alkyls (CH 3 -C 16 H 33 ) in ester moiety were tested in transition metalion catalyzed liposome peroxidation and compared with AOA of Trolox™ and Probucol™. The compounds with C 2 H 5 -C 4 H 9 residues in the 3,5-position ester moieties exert the most pronounced AOA. The AOA of tested compounds is associated with their ability to incorporate into liposomes. MATERIALS AND METHODS Phospholipid

Effects of diludine supplementation on growth performance, liver antioxidant enzyme activities and muscular trace elements of rainbow trout (Oncorhynchus mykiss) juveniles at a low water temperature

“…Therefore, it is widely used as antioxidant in food and for stabilization of edible oils (Kourimska et al. 1993; Tirzitis et al. 2001).…”

Synthesis and studies of calcium channel blocking and antioxidant activities of novel 4-pyridinium and/or N-propargyl substituted 1,4-dihydropyridine derivatives

“…Ca 2+ antagonism, IC 50 (mM) Cell SH-SY5Y A7r5 antioxidant activity of the synthesised 1,4-DHP derivatives. Diludine (diethyl-1,4-dihydro-2,6-dimethyl-3,5pyridinecarboxylate), a well-known 1,4-DHP derivative with antioxidant properties [37,38], was used as a positive control. The obtained results ( Fig.…”

“…4 (m, 5H). 13 C NMR (CDCl 3 ) d: 14.22; 15.21; 36.38 (N-CH 2 ); 38.52 (4-C-DHP); 60. 21 6.86; N, 3.81; found: C, 71.59; H, 6.90; N, 3.77 2).…”

Radical scavenging activity of decalpoline, a novel compound characterized from Decalepis hamiltonii

“…Decalpoline is observed to have more potent metal chelating activity than its source extract and BHA (Table 3), which is due to -OH, -O-, and C=O functional groups. In addition, the presence of the 6 CH 3 functional groups may also be responsible for the synergistic effect of decalpoline [21][22][23]. It has been reported that structures containing two or more of the functional groups -OH, -SH, -COOH, -PO 3 H 2 , C=O, -NR 2 , -S-, and -O-in a favorable structurefunction configuration are responsible for their metal chelating activity [24,25].…”