Antioxidants future research

Prevention of vascular disease is one of the goals of a study in progress in Sweden, in which newly diagnosed diabetic children have been randomized in a doubleblind study where one group receives placebo and the other a preparation containing ascorbic acid, )3-carotene, nicotinamide, selenium and vitamin E (Ludvigsson, 1992). Future research with antioxidants may attempt to prevent the onset of pancreatic beta-cell destruction in the prediabetic phase of susceptible individuals. 

Future research should also focus its attention on the factors/mechanisms that regulate free-radical activity in vivo. The complex interrelationship between cellular and extracellular levels of antioxidants needs to be clarified, and factors that govern the synthetic rate of the scavenging enzymes, for example, SOD or catalase will provide further insight into cellular redox control. 

Several centers have been collecting human samples, including urine, breast milk, peripheral blood, cord blood, meconium, vernix, saliva, hair, and placental tissue (Eskenazi et al. 2005). The samples have been analyzed for the presence of numerous substances, such as mercury, lead, cotinine, pesticides, phthalates, PAHs, PAH-DNA adducts, allergens, endotoxin, antioxidant micronutrients, cytokines, immunoglobulin E, cholinesterase, and thyroid hormones. The centers have also been storing samples for future research purposes (Eskenazi et al. 2005). 

Nevertheless, we can already state with certainty that phytopolyphenols play a much wider role than acting merely as an antioxidant, which function was the first to be demonstrated for this extremely versatile class of plant secondary metabolites that appear to be important for human health. It is hoped that the extremely vigorous research activities involving the effects of phytopolyphenols on the signal transduction pathways in vivo will be initiated. We consider this topic one of the most exciting areas for future research in the field of traditional medicine and food science. 

Abstract Biodegradable thermoplastic materials offer great potential to be used in food packaging or biomedical industry. In this chapter we will present a review of the research done on starch and starch nanocomposites. In the case of nanocomposites based on starch, special attention will be given to the influence of starch nanoparticles, cellulose whiskers, zinc oxide nanorods, antioxidants, and antimicrobial inclusion on the physicochemical properties of the materials. The discussion will be focused on structural, mechanical, and barrel properties as well as on degradation, antibacterial and antioxidant activities. Finally, we will discuss our perspectives on how future research should be oriented to contribute in the substitution of synthetic materials with new econanocomposites. 

These findings provided a strong incentive for the initiation of intervention studies to investigate whether a lack of dietary antioxidants is causally related to chronic disease risk and if providing antioxidant supplements confers benefits for the prevention and treatment of these conditions. This article summarizes the findings of the largest primary and secondary trials published to date and considers their implications for future research and current dietary advice. 

Another vitamin which may be concerned in the oxidation of fats is ascorbic acid, which according to Golumbic and Mattill (7) enhances the activity of tocopherols in preventing the oxidation of certain vegetable fats. Aqueous colloidal solutions of carotene, without tocopherol, are also protected by ascorbic acid (8). It is clear, therefore, that the vitamins mentioned, and also the essential linoleic acid, may interact in fatty mediums either as substances liable to oxidation, or as antioxidants. It seems probable that future research will reveal other instances of interaction in fatty media, and possibly will implicate other vitamins. Already Paveek and Shull (9) have shonm that biotin is inactivated by rancid fats, from which it is protected by tocopherol. While in some cases the chemical behavior of the vitamins in fats may be related to their physiological activity, in others tlieir reactions when exposed to oxidative influences may merely conform with those of the other constituents of the fat. 

Many methods are available for determining food antioxidant capacity, which is an important topic in food and nutrition research. However, there is a great need to standardize these methods because the frequent lack of an actual substrate in the procedure, the system composition, and the method of inducing oxidation could limit their accuracy. In fact, antioxidant activities in complex systems cannot be evaluated satisfactorily using a single test, and several test procedures may be required. The search for more specific assays that can be more directly related to oxidative deterioration of foods and biological systems should be the objective of future investigations. 

At present, extensive research has been conducted on the antioxidant and antimicrobial properties of wines. Similar studies on vermouth should be conducted in-depth. Generally, red wine is considered better than white with respect to antioxidant effect. How red versus white vermouths compare in these regards needs to be determined. Though vermouth is a traditional commercial product, the relationship of its flavor attributes to its chemical constituents and is lacking. It could be a fertile field for future studies. In addition, few studies have been conducted on its maturation and the changes that occur during aging. The use of noncaloric sweeteners is another topic worthy of evaluation relative to its acceptability by diabetics. 

Both clinical and basic studies of oxidative stress are needed to further clarify their role in aging and age-related diseases. Here, it is important to more clearly define the dietary needs of various antioxidants to slow aging and lower disease incidence. Previous research has focused on slowing the rates of adverse reactions future efforts should probably be directed toward decreasing free radical initiation rates. 

Parks E and Trader MG (2000) Mechanisms of vitamin E regulation research over the past decade and focus on the future. Antioxidants and Redox Signaling 2,405-12. Rayman M (2000) The importance of selenium to human health. Lancet 356, 233-41. Rlcciarelli R, Zingg JM, andAzziA(2001) Vitamin E protective role of a Janus molecule. FASEB Journal 15,2314-25. 

Parks E and Traber MG (2000) Mechanisms of vitamin E regulation research over the past decade and focus on the future. Antioxidants and Redox Signaling 2,405-12. 

Simultaneous with the in vitro research, reports are appearing from the nutritional and human medical areas focusing on bioavailability of flavonoids and the importance of dietary antioxidants in preventing diseases such as coronary heart disease, cancer, vision deterioration and aging in vivo. When these two approaches meet in the hopefully not-too-distant future, the results should reveal scientifically sound conclusions regarding the health benefits of flavonoids. Although there is still much to be learned, there are indications that the scientific approach may reaffirm the basis for many of the remedies known from traditional therapeutic use of grape and berry products in folk medicine. 

---