Abstract
The antioxidant properties of two apple dihydrochalcones, namely phloretin and phloridzin, were evaluated and compared with those of α-tocopherol and butylated hydroxytoluene (BHT). The effects were studied in an oil-in-water emulsion system containing methyl linolenate (ML), methyl eicosapentaenoate (MEPA), and methyl docosahexaenoate (MDHA) in which oxidation was initiated by the peroxyl radical generator 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH) and in fish oil where oxidation was initiated thermally. In the emulsion system, phloretin (1 and 5 mM) completely inhibited the oxidation of ML tested as evidenced by the thiobarbituric acid reactive substances (TBARS) assay. Under the same conditions, phloridzin was less effective than phloretin, but still more effective than α-tocopherol. Both phloretin and phloridzin molecules had a marginal inhibitory effect against oxidation of fish oil induced by heating at 70 °C for 3 hours, when compared to BHT. These results indicate that phloretin and phloridzin have the potential to suppress lipid oxidation in polyunsaturated fatty acid (PUFA) containing foods.
Highlights
Polyunasaturated fatty acids (PUFA) are highly oxidizable molecules and reactive with hydroxyl and peroxyl radicals due to the presence of multiple double bonds [1]
Fish oil by apple skin extracts containing phloretin and phloridzin has been reported [16], but the antioxidant protection of omega-3 PUFA afforded by these two dihydrochalcones individually has not been reported, the objective of this research was to evaluate the antioxidant activity of phloretin and phloridzin in reducing the oxidation of some representative PUFA methyl esters: methyl linolenate (ML), methyl eicosapentaenate (MEPA) and methyl docosahexaenoate (MDHA) in an oil-in-water emulsion and fish oil in comparison with α-tocopherol and butylated hydroxytoluene (BHT)
In order to investigate the antioxidant ability of two predominant dihydrochalcones of apples, phloretin and phloridzin, in protecting PUFA from oxidation, two model systems, namely peroxyl radical-induced oxidation of ML, methyl eicosapentaenoate (MEPA) and MDHA in oil-in-water emulsion and heat-induced oxidation of fish oil were employed
Summary
Polyunasaturated fatty acids (PUFA) are highly oxidizable molecules and reactive with hydroxyl and peroxyl radicals due to the presence of multiple double bonds [1]. The use of omega-3 PUFA as value-added food ingredients has increased [8]; prevention of PUFA oxidation has received renewed attention Synthetic antioxidants such as butylated hydroxytoluene (BHT) have been used to prevent oxidation of PUFA but their future use has been questioned due to their potential carcinogenic properties [9,10]. Phloretin (β-(4-hydroxyphenyl)-1-(2’,4’,6’-trihydroxypropiophenone) and its glucoside phloridzin (phloretin-2β-D-glucose; called phlorhizin or phlorizin) (Figure 1), which belong to the dihydrochalcone (bicylic flavonoid) flavonoid sub-class, are abundantly found in apples [12]. In addition to their free radical scavenging properties [13], dihydrochalcones possess numerous biological activities [14]. The antioxidant protection of omega-3 PUFA and fish oil by apple skin extracts containing phloretin and phloridzin has been reported [16], but the antioxidant protection of omega-3 PUFA afforded by these two dihydrochalcones individually has not been reported, the objective of this research was to evaluate the antioxidant activity of phloretin and phloridzin in reducing the oxidation of some representative PUFA methyl esters: methyl linolenate (ML), methyl eicosapentaenate (MEPA) and methyl docosahexaenoate (MDHA) in an oil-in-water emulsion and fish oil in comparison with α-tocopherol and BHT
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call