Radical scavenging activity

Fig. 3. a) First order plot of oxygen uptake in the Methylene-blue (MB)-sensitized photooxidation of GA 8.4 pM and 1.3 mM histidine (control) in phosphate buffer pH 7. b) Percentage radical scavenging activity for the control molecule Trolox and GA at pH 7.4 in phosphate buffer 10 mM (hydroxyl radical) and pH 10 in sodium carbonate buffer 50 mM (anion superoxide radical). 

The antioxidant property of ferulic acid and related compounds from rice bran was reported by Kikuzaki et al, (2002). Their results indicated that these compounds elicit their antioxidant function through radical scavenging activity and their affinity with lipid substrates. Another recent study reported by Butterfield et al, (2002) demonstrated that ferulic acid offers antioxidant protection against hydroxyl and peroxyl radical oxidation in synaptosomal and neuronal cell culture systems in vitro. The effect of ferulic acid on blood pressure (BP) was investigated in spontaneously hypertensive rats (SHR). After oral administration of ferulic acid the systolic blood pressure (SBP) decreased in a dose-dependent manner. There was a significant correlation between plasma ferulic acid and changes in the SBP of the tail artery, suggesting... 

This interceptor theory does not seem to be the only protective mechanism in operation. Inhibition of cytochrome P450 enzymes related to the bioactivation of mutagens and toxic radical scavenger activities have been proposed to integrate the different modes of action. Other investigations have reported the involvement of chlorophyUin in inducing apoptosis in human colon cells, which may be important in limiting cancer cell invasion and metastasis. ... 

De Ancos, B., Gonzalez, E., and Cano, M.P., Effect of high-pressure treatment on the carotenoid composition and the radical scavenging activity of persimmon fruit purees, J. Agric. Food Chem., 48, 3542, 2000. 

Nakajima, 1.1. et al., LC/PDA/ESl-MS profiling and radical scavenging activity of anthocyanins in various herries, J. Biomed. Biotechnol., 241, 2004. 

Pippenger, C.E., Meng, X., Stolfi, V, McGonagle, B. and Fazio, V.W. (1991). Free radical scavenging activities and trace element concentrations in erythrocytes and plasma of adult patients with inflammatory bowel disease. In Inflammatory Bowel Diseases. Progress in Basic Research and Clinical Implications (eds. H. Gocbell, K. Ewe, H. Malchow and Ch. Koelbel) p. 33. Kluwer Academic Publishers, Lancaster. 

Bain, S.C., Le Guen, C.A., Lunec, J. and Barnett, A.H. (1991). Comparison of the free radical scavenging activity of captopril versus enalapril a three-month trial in vivo study in hypertensive diabetic patients. J. Human Hypertens. 5, 511-515. 

A major contribution of the free-radical scavenging activity in blood plasma is attributable to the macro-molecular proteins (Wayner et al., 1985) of which albumin is a primary component and trapping agertt (Holt et al., 1984). Serum sulphydryl levels, primarily albumin-related, are decreased in subjects with rheumatoid complicated coalworkers pneumoconiosis, indicative of exacerbated inflammatory R.OM production (Thomas and Evans, 1975). Experimental asbestos inhalation in rats leads to an adaptive but evidendy insufficient response by an increase in endogenous antioxidant enzymes (Janssen etal., 1990). Protection of the vascular endothelium against iron-mediated ROM generation and injury is afforded by the iron sequestiant protein ferritin (Balia et al., 1992). 

The purported prophylactic use of Japanese herbal medicines to combat neuronal ageing has been related to their free-radical scavenging activity (Hiramatsu a al., 1992). Inhibition of the pro-inflammatory effects of cytokine interleukin-1 by recombinant endogenous interleukin-1 receptor antagonist in experimental rats is associated with alleviation of excitotoxic neuronal damage, an action which has also been related to the antiinflammatory effect of lipocortin 1 (Relton and Roth well, 1992). 

Jinno, J., Mori, H., Oshiro, Y., Kikuchi, T. and Sakurai, H. (1991). Evaluation of free radical scavenging activity of OPC-14117 by electron spin resonance technique. Free Rad. Res. Commun. 15, 223-230. 

Baltrusaityte, V., Venskutonis, P. R., and Ceksteryte, V. (2007b). Radical scavenging activity of different floral origin honey and beebread phenolic extracts. Food Chem. 101, 502-514. 

An extract from Lactuca indica showed significant free radical scavenging activity, and protected phixl74 supercoiled DNA against strand cleavage and reduced oxidative stress in human promyelocytic leukemia HL-60 cells. On account of protocatechulic acid, methyl p-hydroxybenzoate, caffeic acid, 3,5-dicaffeoylquinic acid, luteolin 7-O-fT glucopyranoside, and quercetin 3-0-(3-g 1 ucopyranoside are the major antioxidative constituents (111). 

Gollucke APB, Catharino RR, de Souza JC, Eberlin MN and de Queiroz Tavares D. 2008. Evolution of major phenolic components and radical scavenging activity of grape juices through concentration process and storage. Food Chem 112(4) 868—873. 

The 3-morpholinosydnonimine system generates superoxide radicals and nitrogen monoxide, forming peroxynitrite, which releases ethane from KMB (a-keto-y-methiolbutyric acid). This method was used by Lavelli and others (1999) to investigate the radical-scavenging activity of fresh and air-dried tomatoes. 

This method is based on the radical scavenging activity of antioxidants toward the... 

Anagnostopoulou MA, Kefalas P, Papageorgiou VP, Assimopoulou AN and Boskou D. 2006. Radical scavenging activity of various extracts and fractions of sweet orange peel (Citrus sinensis). Food Chem 94 19-25. 

Bajpai M, Mishra A and Prakash D. 2005. Antioxidant and free radical scavenging activities of some leafy vegetables. Int J Food Sci Nutr 56(7) 473-481. 

Calliste CA, Trouillas P, Allais DP, Simon A and Duroux JL. 2001. Free radical scavenging activities measured by electron spin resonance spectroscopy and B16 cell antiproliferative behaviors of seven plants. J Agric Food Chem 49(7) 3321-3327. 

Chinnici F, Bendini A, Gaiani A and Riponi C. 2004. Radical scavenging activities of peels and pulps from cv. golden delicious apples as related to their phenolic composition. J Agric Food Chem 52(15) 4684-4689. 

Kefalas P, Kallithraka S, Parejo I and Makris DP. 2003. A comparative study on the in vitro antiradical activity and hydroxyl free radical scavenging activity in aged red wines. Food Sci Technol Int 9(6) 383-385. 

Lavelli V, Hippeli S, Peri C and Elstner EF. 1999. Evaluation of radical scavenging activity of fresh and air-dried tomatoes by three model reactions. J Agric Food Chem 47(9) 3826—3831. 

Liu JK, Hu L, Dong ZJ and Hu Q. 2004. DPPH radical scavenging activity of ten natural p-terphenyl derivatives obtained from three edible mushrooms indigenous to China. Chem Biodiv 1 (4) 601—605. 

Noda Y, Anzai K, Mori A, Kohno M, Shinmei M and Packer L. 1997. Hydroxyl, end superoxide anion radical scavenging activities of natural source antioxidants using the computerized JES-FR30 ESR spectrometer system. Biochem Mol Biol Int 42(1) 35—44. 

Ordoudi SA and Tsimidou MZ. 2006. Crocin bleaching assay (CBA) in structure-radical scavenging activity studies of selected phenolic compounds. J Agric Food Chem 54(25) 9347-9356. 

Orhan I, Aydin A, Colkesen A, Sener B and Isimer AI. 2003. Free radical scavenging activities of some edible fruit seeds. Pharm Biol 41(3) 163—165. 

Polasek M, Skala P, Opletal L and Jahodar, L. 2004. Rapid automated assay of anti-oxidation/radical-scavenging activity of natural substances by sequential injection technique (SIA) using spectrophotomet-ric detection. Anal Bioanal Chem 379(5—6) 754—758. 

Sanchez-Moreno C. 2002. Review Methods used to evaluate the free radical scavenging activity in foods and biological systems. Food Sci Technol Int 8(3) 121—137. 

Schmeda-Hirschmann G, Feresin G, Tapia A, Hilgert N and Theoduloz C. 2005. Proximate composition and free radical scavenging activity of edible fruits from the Argentinian Yungas. J Sci Food Agric... 

Singh N and Rajini PS. 2003. Free radical scavenging activity of an aqueous extract of potato peel. Food Chem 85 611-616. 

Antioxidant capacity can be measured by several techniques, each of which has its own limitations. Antioxidant capacity of fruit juices and purees was evaluated by the DPPH method (which measures the radical-scavenging activity against a nonphysio-logical free radical), and treatment of these products with PEF or HHP resulted in losses... 

Wang CY, Wang SY, Yin JJ, Parry J and Yu LL. 2007. Enhancing antioxidant, antiproliferation, and free radical scavenging activities in strawberries with essential oils. J Agric Food Chem 55(16) 6527-6532. 

Huge literature on biological functions of flavonoids and their antioxidant and free radical scavenging activities successfully competes with work on antioxidant effects of vitamins E and C. Flavonoids have been reported to exert multiple biological effects and exhibit antiinflammatory, antiallergic, antiviral, and anticancer activities [85 89], However, considering flavonoids as the inhibitors of free radical-mediated processes, two types of their reactions should be discussed flavonoids as free radical scavengers (antioxidants) and flavonoids as metal chelators. 

From chemical point of view, efficient free radical scavengers must contain substituents with the very weak C—H, O—H, or S—H bonds, from which reactive free radicals are able to abstract a hydrogen atom. It can be seen that the antioxidants discussed above (ascorbic acid, a-tocopherol, ubihydroquinones, glutathione, etc) fall under this category. However, many other compounds manifest free radical scavenging activity in in vitro and in vivo systems. 

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