Antioxidative potential

Cyanobacteria and algae have evolved a complex defense system against ROS, including non-enzymatic antioxidants like carotenoids, tocopherols (vitamin E), ascorbic acid (vitamin C) and reduced glutathione (Asada 1994). 

Carotenoids exhibit multiple physiological roles, i.e. as light-harvesting pigments in photosynthesis, as quenching solutes for the triplet state of chlorophyll a to 

Tocopherols are the second major class of lipid-soluble antioxidants inphotosynthetic membranes. Their primary function is to protect cells from hpid peroxidation. The water-soluble ascorbic acid also significantly acts against hpid peroxidation and DNA damage. However, these low-molecular weight antioxidants are chemically consumed and hence not considered the most efficient detoxifying agents. 

In contrast, antioxidant enzymes can efficiently counteract all UV-induced ROS (Aguilera et al. 2002). These enzymes are represented by superoxide dismutase (SOD), catalase and glutathione peroxidase as well as those involved in the ascorbate-glutathione cycle, such as ascorbate peroxidase, mono-dehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase. One of the most important classes of antioxidant enzymes is the SOD family, which eliminate noxious superoxide radical anions. Different metalloforms of SOD exist (Fe, Mn, CuZn and Ni), which due to their intracellular localisation protect different cellular proteins (Lesser and Stochaj 1990). 

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Fig. 16.2 Examples of plant phenols with antioxidative potential in foods.

Antioxidant potential of intermediates in phenylpropanoid metabolism in higher FEBS Letters, 368, 188-92. 

GARDNER p T, MCPHAIL D B and DUTHIE G G (1998) Electron spin resonance spectroscopic assessment of the antioxidant potential of teas in aqueous and organic media, J Sci Food Agric, 76, 257-62. 

GRAF E (1992) Antioxidant potential of ferulic acid. Free Radical Biol Med, 13(4) 435-48. 

Some of the advantages of astaxanthin over other carotenoids include (1) better stability compared to other carotenoids, (2) high antioxidant potential (10 times... 

Taken together, these observations emphasize the critical importance of maintaining the antioxidant potential of the pancreatic beta cell in ordet to ensure both its survival and insulin secretory capacity during times of increased oxidative stress. 

Antioxidant-potentiality of gold-chitosan nanocomposites. Colloids and Surface Science B, 32, 117-123. 

Langley-Evans SC. 2000. Consumption of black tea elicits an increase in plasma antioxidant potential in humans. Int J Food Sci Nutr 51(5) 309-315. 

Palace VP, Khaper N, Qin Q and Singal PK. 1999. Antioxidant potentials of vitamin A and carotenoids and their relevance to heart disease. Free Rad Biol Med 26 746—761. 

The photochemiluminiscence (PCL) assay was initially used by Popov and others (1987). Popov and Lewin (1994 1996) have extensively studied this technique to determine water-soluble and lipid-soluble antioxidants. The PCL assay measures the antioxidant capacity, toward the 02 radical, in lipidic and water phase. This method allows the quantification of both the antioxidant capacity of hydrophilic and/or lipophilic substances, either as pure compounds or complex matrices from different origin synthetic, vegetable, animal, human, etc. The PCL method is based on an approximately 1,000-fold acceleration of the oxidative reactions in vitro by the presence of an appropriate photosensitizer. The PCL is a very quick and sensitive method. Chua and others (2008) used this assay to determine the antioxidant potential of Cin-namomum osmophloeum, whereas Kaneh and Wang and others (2006) determined the antioxidant capacity of marigold flowers. The antioxidant activity of tree nut oil extracts was also assessed by this method (Miraliakbari and Shahidi 2008). 

DCFH-DA assay was first developed by Valkonen and Kuusi (1997) as an alternative to measure the total peroxyl radical-trapping antioxidant potential of plasma. This assay uses AAPH to generate peroxyl radicals and DCFH-DA as the oxidizable substrate for the generated radicals. The oxidation of DCFH-DA by peroxyl radicals converts DCFH-DA to dichlorofluorescein. DCF is highly fluorescent (excitation 480 nm, emission 526 nm) and also shows absorbance at 504 nm. Therefore, the produced DCF can be monitored either fluorometrically or spectrophotometrically. 

Campos AM and Lissi EA. 1996. Total antioxidant potential of Chilean wines. Nutr Res 16(3) 385—389. 

Ferreres F, Sousa C, Valentao P, Seabra RM, Pereira JA and Andrade PB. 2007a. Tronchuda cabbage Brassica oleracea L. var. costata DC) seeds phytochemical characterization and antioxidant potential. Food Chem 101(2) 549-558. 

Gardner PT, White TAC, McPhail DB and Duthie GG. 2000. The relative contributions of vitamin C, carotenoids and phenolics to the antioxidant potential of fruit juices. Food Chem 68(4) 471—474. 

Jung ST, Park YS, Zachwieja Z, Folta M, Barton H, Piotrowicz J, Katrich E, Trakhtenberg S and Gorinstei, S. 2005a. Some essential phytochemicals and the antioxidant potential in fresh and dried persimmon. Int J Food Sci Nutr 56(2) 105-113. 

Pereira JA, Pereira APG, Ferreira ICFR, Valentao P, Andrade PB, Seabra R, Estevinho L and Bento A. 2006. Table olives from Portugal phenolic compounds, antioxidant potential, and antimicrobial activity. J Agric Food Chem 54(22) 8425-8431. 

Roy MK, Takenaka M, Isobe S and Tsushida T. 2007. Antioxidant potential, anti-proliferative activities, and phenolic content in water-soluble fractions of some commonly consumed vegetables effects of thermal treatment. Food Chem 103(1) 106-114. 

Valkonen M and Kuusi T. 1997. Spectrophotometric assay for total peroxyl radical-trapping antioxidant potential in human serum. J Lipid Res 38(4) 823-833. 

Robles-Sanchez M, Gorinstein S, Martin-Belloso O, Astiazaran-Garcia H, Gonzalez-Aguilar GA and Cruz-Valenzuela R. 2007. Minimal processing of tropical fruits antioxidant potential and its impact on human health. Intersciencia 32(4) 227-232. 

Simonetti, P., Pietta, P., and Testolin, G., Polyphenol content and total antioxidant potential of selected Italian wines, J. Agric. Food Chem., 45, 1152, 1997. 

Valvi SR, Rathod VS, Yesane DP. Screening of three wild edible fmits for their antioxidant potential. Current Botany. 2011 2(1) 48-52. 

Krishnaiah D, Sarbatly R, Nithyanandam R. A review of the antioxidant potential of medicinal plant species. Food and Bioproducts Processing. 2011 8 9 217-233. 

The main effect of efferent action of Hepamal preparation is inhibition of LPO processes, increase of antioxidative abiUty of the organism and stimulation of enzymes of the organism s detoxication system. These activities are stipulated by natural vitamin complexes (A, E, PP, C, 6-carotenes, foUc acid) present in Hepamal, which have high antioxidative potential, whereas flavonoids and terpenoids, also present in the preparation, stimulate both detoxication phases. 

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