Studies on Antioxidants

Only a few articles have been published examining the effects of various antioxidant packages on the thermo-oxidative degradation of aromatic polyesters [3-19]. 

Angelova and co-workers [4, 5] used differential thermal analysis (DTA) to examine the effects of some antioxidants on PET and model 

Zimmermann [6] noted that phosphites, while effective thermal stabilisers (see Chapter 6), were also effective antioxidants, especially if used in combination with primary antioxidants such as hindered phenols. 

Kosinska and co-workers [7] suggested that hindered phenols and secondary aromatic amines could be effective antioxidants in PET. 

Karayannidis and co-workers investigated the effect of various phosphorus-containing compounds on the thermo-oxidative stability of PET [9]. Additives were incorporated in the reaction kettle after the transesterification stage, but before polycondensation. Additives investigated were phosphoric acid, tributylphosphate, triphenylphosphate, phenylphosphonic acid, phenylphosphinic acid and sodium phenylphosphinate. The most effective antioxidants were tributylphosphate, phenylphosphonic acid and phenylphosphinic acid. 

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Kardinaal, A.E. et al.. Association between beta-carotene and acute myocardial infarction depends on polyunsaturated fatty acid status the EURAMIC study (European Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast), Arterioscler. Thromb. Vase. Biol, 15, 726, 1995. 

Masuda, T. et ah. Chemical studies on antioxidant mechanism of curcumin analysis of oxidative coupling products from curcumine and linoleate, J. Agric. Food Chem., 49, 2539, 2001. 

Public health (studies on antioxidative homeostasis in various segments of the population the meaning of which could potentially unravel the rele-... 

T. Ozaki. Studies on antioxidative sub- SI132 stances in sesame seed. AgrBiol Chem... 

Chemical and biochemical studies on antioxidant components of ginseng. Advances in Chinese medicinal materials research H. M. Chang, H. W. Yeung, W. W. Tso, and A. Koo (eds.). World Scientific Press Philadelphia, PA, 1984 pp. 485-498. 

Ito, N., Hiroze, M., Fukushima, G., Tauda, H., Shira, T., Tatematsu, M. (1986). Studies on antioxidant their carcinogenic and modifying effects on chemical carcinogensis. Eood Chem. Toxicol., 24, 1071-1081. 

Yamaguchi, N. Yokoo, Y. Fujimaki, M. Studies on antioxidative activities of amino compounds on fats and oils. III. Antioxidative activities of soybean protein hydrolyzates and synergistic effect of hydrolyzate on tocopherol. Nippon Shokuhin Kogyo Gakkaishi 1975, 22, 431-5. 

Chidambara Murthy, K.N., Jayaprakasha, G.K., and Singh, R.P., Studies on antioxidant activity of pomegranate (Punica granatum) peel extract using in vivo models, J. Agric. Food Chem., 50,4791, 2002. 

Voorrips LE, Goldbohm FRA, Brants HAM, et al, A prospective cohort study on antioxidant and folate intake and male lung cancer risk. Cancer Epidemiol Biomarkers Prev 2000 9 357-365,... 

MRC/BHF Heart Protection Study on antioxidant vitamin supplementation in 20536 high-risk individuals a randomized placebo-controlled trial. Lancet 2002 360 23-33. 

Sang, S., Liao, C.H., Ran, M.H., Rosen, R.T., Shiau, S.Y.L., Lin, J.K. and Ho, C.T. (2002) Chemical studies on antioxidant mechanism of garcinol analysis of radical reaction products of garcinol with peroxyl radicals and their antitumor activities. Tetrahedron 58(51), 10095-10102. 

As part of a study on antioxidants the halfwave oxidation potential of phenothiazine at a wax-impregnated graphite electrode was determined and the value -f- 239 (mv SCE) was found. 

FIGURE 8.12 Proposed scavenging mechanism of epicatechin and catechin to 2,2-diphenyl-l-picrylhydrazyl. (From Sang, S., Cheng, X., Stark, R. E., Rosen, R. T., Yang, C. S., and Ho, C.-T. 2002. Chemical studies on antioxidant mechanism of tea catechins Analysis of radical reaction products of catechin and epicatechin with 2,2-diphenyl-l-picrylhydrazyl. Bioorg. Med. Chem. 10 2233-37. With permission.)... 

Studies on antioxidant activity in South American medicinal plants are funded by the International Foundation for Science (IFS), in Stockholm, Sweden (Grant agreement No. F/2628-1), BID-CONICET (grant PMT-SID0370) and the University of Buenos Aires (grant UBACYT FA012/J). 

Even less well understood than MA is the possible occurrence of cholesterol oxidation products in foods and their health significance. It seems clear that some of the products of cholesterol autoxidation are atherogenic. Much more research will be required to establish or refute their proposed carcinogenic properties. Methods for the determination of cholesterol oxidation products in foods and studies to establish levels of occurrence, if any, are most urgently needed. Further studies on antioxidants and procedures for the inhibition of oxidation are also needed. It is difficult to overstate the potential importance to the animal products industry of studies on quantification of cholesterol oxides in food products. Concern about this area of research is becoming widespread (47,48). 

Lovern, J. A. 1946. Some aspects of recent British studies on antioxidants. Oil Soap 23, 40. 

Kirigaya, N. Kato, H. Fujimaki, M. Studies on antioxidant activity of nonenzymic browning reaction products. Agric. Biol. Chem. 1968, 32, 287-290. 

Studies on Antioxidant Properties of Lichen Secondary Metabolites... 

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