Myricetin naringin

The most important members of the flavonoid family include anthocyanidins (e.g., cyanidin, delphinidin, malvidin), flavonols (e.g., quercetin, kaempferol), flavones (e.g., luteolin, apigenin), flavanones (e.g., myricetin, naringin, hesperetin, naringenin), flavan-3-ols (e.g., catechin, epicatechin, gallocatechin) and, although sometimes classified separately, the isoflavones (e.g., genistein, daidzein). For chemical structures see Figure 1. All these phytochemical are frequently referred to as bioflavonoids due to well established effects in human health maintenance. 

Numerous studies were dedicated to the effects of flavonoids on microsomal and mitochondrial lipid peroxidation. Kaempferol, quercetin, 7,8-dihydroxyflavone and D-catechin inhibited lipid peroxidation of light mitochondrial fraction from the rat liver initiated by the xanthine oxidase system [126]. Catechin, rutin, and naringin inhibited microsomal lipid peroxidation, xanthine oxidase activity, and DNA cleavage [127]. Myricetin inhibited ferric nitrilotriacetate-induced DNA oxidation and lipid peroxidation in primary rat hepatocyte cultures and activated DNA repair process [128]. 

Compounds 1 = 4-hydroxycoumarin 2 = umbelliferon 3 = 4-methyl-esculetin 4 = isopimpinellin 5 = esculin 6 = flavone 7 = a-naphtoflavone 8 = kaempferol 9 = quercetin 10 = isoquercitrin 11 = robinetin 12 = robinin 13 = myricetin 14 = luteolin 7-O-glucoside 15 = rutin 16 = hes-peretin 17 = hespiridin 18 = naringin 19 = pelargonin chloride 20 = polargonin chloride 21 = malvin chloride. 

Fig. 2.45. Gradient elution chromatogram of flavonoids investigated. Peak identification 1 = naringin 2 = hesperidin 3 = quercitrin 4 = myricetin 5 = naringenin 6 = hesperetin 7 = luteolin 8 = apigenin 9 = flavone 10 = acacetin. Reprinted with permission from M. A. Hawryt et al. [136].

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