Antioxidant anthocyanidins

Fig. 16 Antioxidative anthocyanidins, catechins, and anti-inflammatory and an antitumor agents...

Among the plant phenols, the flavonoids and the anthocyanidins, belonging to the 1,3-diphenylpropans, have been studied in most detail, mainly because of their potential health benefits. With more than 4,000 different flavonoids known, systematic studies of the effects of variation in molecular structure on physico-chemical properties of importance for antioxidative effects have also been possible (Jovanovic et al, 1994 Seeram and Nair, 2002). Flavonoids were originally found not to behave as efficiently as the classic phenolic antioxidants like a-tocopherol and synthetic phenolic antioxidants in donating... 

Anthocyanins and anthocyanidins, compounds present with high structural diversity in fruits and wines, showed a pattern as antioxidants different from that of the tea catechins with respect to the effect of substituents. In a liposomal model system induced peroxidation was inhibited increasingly by anthocyanins/ anthocyanidins with an increasing number of hydroxyl groups in the B-ring (Fig. 16.6), while the opposite was seen for the catechins (Seeram and Nair, 2002). For anthocyanidins, the presence of a 3-hydroxy group is important... 

Prior RL, Cao G, Martin A, Sofic E, McEwen J, OBrien C, Lischner N, Ehlenfeldt M, Kalt W, Krewer G and Mainland CM. 1998. Antioxidant capacity as influenced by total phenolic and anthocyanidin content, maturity, and variety of Vaccinium species. J Agric Food chem. 46 2686-2693. 

Flavonoids protect LDL from oxidation, delaying the onset of lipid peroxidation, however, the prevention of atherosclerosis by flavonoids occurs not only by the inhibition of LDL oxidation, but also by the increase of cellular resistance to harmful effects of the oxidized LDL (de Luis and Aller, 2008). The antioxidant activity of anthocyanidins, as well as their protective role against LDL oxidation, has been well demonstrated in different in vitro systems (Aviram and Fuhrman, 2002 Satue-Gracia and others 1997 Teissedre and others 1996). 

The scavenging ability toward O2 can also be measured by using electron spin resonance (ESR) spectrometry. The 02 anion is trapped with 5,5-dimethyl-1-pyrroline TV-oxidc (DMPO), and the resultant DMPO-OH adduct is detected by ESR using manganese oxide as internal standard. Noda and others (1997) used this technique to evaluate antioxidant activities of pomegranate fruit extract and its anthocyanidins (delphinidin, cyanidin, and pelargonidin). 

Noda Y, Kaneyuki T, Mori A and Packer L. 2002. Antioxidant activities of pomegranate fruit extract and its anthocyanidins delphinidin, cyanidin, and pelargonidin. J Agric Food Chem 50(1) 166-171. 

Bilberry Vaccinium myrtillus) Uses Prevent/treat visual problems such as cataract, retinopathy, myopia, glaucoma, macular degeuCTation treat vascular problems such as hemorrhoids, varicose veins Actions Contains anthocyanidin that X vascular permeability, inhibit pit aggregation thrombus formation, t antioxidant effects on LDLs liver, t regeneration of rhodopsin... 

Anthocyanins are composed of anthocyanidines and their sugar molecules. Anthocyanins are one of the most typical phy to chemicals in the pigments of the plant kingdom with various colors such as carotenoids. Surprisingly, the anthocyanins of over 150 flavonoids are highly antioxidative. To date, it is thought that more than 4000 flavonoids have been identified [7]. 

The polyphenols such as anthocyanidins might have a protective effect on atherosclerosis. This concept suggests that the Recommended Optimal Intake (ROI) is a more important factor for the antioxidation than the Recommended Dietary Allowance (RDA). Now, considering the absence of the appropriate methodology to identify anthocyanidins in the plasma, the analysis of the plasma antioxidant capacity might be a suitable index to define the optimal nutritional intake [95]. 

The first chapter, Functionality of Anthocyanins as Alternative Medicine by Noboru Motohashi and Hiroshi Sakagami, presents their antioxidant mechanism for anthocyanidins, which are present in common foods. It is possible that anthocyanins may have been used both preventatively and clinically as part of many folklore medicines worldwide and may have provided healthcare benefits since the appearance of mankind some 7.5 million years ago. The review will inform the reader as to their functionality and mechanism. 

Cyanidin inhibits epidermal growth factor receptor tyrosine kinase (EGF-RTK), a-glycosidase and COX-1 and COX-2. Delphinidin (3,5,7,3, 4, 5 -hexahydroxyflavylium) also inhibits EGF-RTK. Anthocyanidins and anthocyanins can be anti-inflammatory antioxidants by acting as free radical scavengers. Thus, nasunin (delphinidin-3-(j6-coumaroylrutinoside)-5-glucoside) scavenges OH (hydroxyl), 02 (superoxide) and lipid peroxyl radicals and inhibits lipid peroxidation. 

Yue, X. Xu, Z. 2008. Changes of anthocyanins, anthocyanidins, and antioxidant activity in bilberry extract during dry heating. J. Food Sci. 73 C494-C499. 

The antioxidant activity of a compound depends upon which free radical or oxidant is used in the assay (Halliwell and Gutteridge, 1995), and a different order of antioxidant activity is therefore to be expected when analyses are performed using different methods. This has been demonstrated by Tsuda et al. (1994) in their study of antioxidative activity of an anthocyanin (cyanidin-3-O-p-D-glucosidc) and an anthocyanidin (cyanidin) in four different lipophilic assay systems. Both compounds had antioxidative activity in all four systems, but the relative activity between them and their activity, compared with Trolox, varied with the method used. Fukumoto and Mazza (2000) reported that antioxidant activity of compounds with similar structures gave the same trends, although not always the same results, when measured by P-carotene bleaching, DPPH and HPLC detection of malonaldehyde formation in linoleic acid emulsion. 

To prevent oxidation of reduced organosulfur in the wood cell walls, conservators are currently investigating antioxidants. Commercial antioxidants (ascorbic acid, anthocyanidins, proanthocyanins, flavon-3-ols, flavonones and flavonols) are being used to prevent oxidation of reduced species by mopping up free radicals. 

Fig. (2). General structures of antioxidant flavones, flavonols and anthocyanidins.

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