Capacity of Reductants and Chelators To Prevent Lipid Oxidation Catalyzed by Fish Hemoglobin

Abstract

The efficiency of different reductants (reduced glutathione, ascorbic acid, and catalase) and metal chelators [ethylenediaminetetraacetic acid (EDTA), citric acid, sodium tripolyphosphate (STPP), and adenosine-5'-triphosphate (ATP)] to inhibit lipid oxidation promoted by fish hemoglobin was investigated. The inhibitory activity on hemoglobin-catalyzed lipid oxidation was also evaluated for grape oligomeric catechins (proanthocyanidins), which have both reducing and chelating properties. The antioxidant activity was studied in two different lipid oxidation models, liposomes and washed minced fish muscle. Grape proanthocyanidins were found to be significantly more effective than other reductants to prevent hemoglobin-mediated lipid oxidation in both liposomes and washed fish muscle. Reduced glutathione was also efficient to retard lipid oxidation at the same molarity in washed fish muscle, whereas catalase and ascorbic acid showed a lower antioxidant activity. Metal chelators were less active than reductants, and consequently, the former were necessarily evaluated at much higher concentration than grape proanthocyanidins and reducing compounds. STPP was found to be the iron chelator with the strongest efficiency to delay hemoglobin-mediated lipid oxidation followed by EDTA. Citric acid and ATP were ineffective in retarding lipid oxidation in both systems. Grape proanthocyanidins provided the most extensive protection to preserve hemoglobin at ferrous state in washed fish muscle. Our results draw attention to the greater capacity of reducing compounds to prevent fish hemoglobin-mediated lipid oxidation in comparison with iron chelators, suggesting that the free radical scavenging and/or reduction of ferrylHb species are crucial actions to avoid the pro-oxidant capacity of fish hemoglobin.

Alterations in the Intestinal Assimilation of Oxidized PUFAs Are Ameliorated by a Polyphenol-Rich Grape Seed Extract in an In Vitro Model and Caco-2 Cells

“…The stability of many fish species has been tested during various refrigerated (20) and frozen (47) storage periods. The observed inhibition of lipid oxidation using the GSE in minced mullet during chilled storage is in agreement with results found in liposomes and mackerel muscle (20,48).…”

“…The same GSE extract has shown high effectiveness against the development of lipid oxidation catalyzed by endogenous prooxidants, like hemoglobin (20,48), in fish muscle. Similarly, red wine polyphenols had an antioxidant effect on heated red muscle tissue homogenate in simulated in vitro gastric conditions (11,16).…”

Comparative study on the effect of acid- and alkaline-aided extractions on mechanically separated turkey meat (MSTM): Chemical characteristics of recovered proteins

“…When exposed to acid and alkaline conditions, proteins carry a net positive and net negative charge, respectively, which is a key factor for obtaining high solubility, along with low viscosity of the initial homogenate. Low viscosity provides separation of insoluble parts, especially membrane lipids, which are known to be the primary substrates for deteriorative changes in lipid oxidation [7] and their removal is expected to increase the stability of the final isolate greatly.…”

Fluorescence imaging and spectroscopy for real-time, in-situ characterization of interactions of free radicals with oil-in-water emulsions

“…Various approaches are commonly employed to reduce generation, propagation and interaction of free radicals with bioactive compounds. These approaches can be broadly classified into two categories: (1) reducing radical generation using metal chelators or scavenging radicals using sacrificial antioxidants (Choe & Min, 2006;Graf et al, 1984); (2) protecting active ingredients using encapsulation techniques (Frankel, 1996;Maestre, Pazos, Iglesias, & Medina, 2009). Encapsulation matrix can provide a physical barrier to limit interactions of free radicals generated in a bulk phase with active ingredients enclosed in an encapsulation barrier (Frankel, Huang, Aeschbach, & Prior, 1996;Heinzelmann, Franke, Jensen, & Haahr, 2000;Weiss et al, 2008).…”