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The sources of natural antioxidants
El?bieta Sikora,Ewa Cie?lik,Kinga Topolska
Acta Scientiarum Polonorum : Technologia Alimentaria , 2008,
Abstract: Intensive oxidative processes occuring in human organism lead to formation of oxygen reactive forms, which can damage systemic cells and tissues. It is shown, that body endogenous protective system can be supported in that case by natural antioxidant compounds provided from food. The assessment of food products as the potential sources of antioxidants was performed, taking into consideration the kinds of compounds supplied, and their significance in the diet of different nations.
Cocoa Flavonoid-Enriched Diet Modulates Systemic and Intestinal Immunoglobulin Synthesis in Adult Lewis Rats  [PDF]
Malen Massot-Cladera,àngels Franch,Cristina Castellote,Margarida Castell,Francisco J. Pérez-Cano
Nutrients , 2013, DOI: 10.3390/nu5083272
Abstract: Previous studies have reported that a diet containing 10% cocoa, a rich source of flavonoids, has immunomodulatory effects on rats and, among others effects, is able to attenuate the immunoglobulin (Ig) synthesis in both systemic and intestinal compartments. The purpose of the present study was focused on investigating whether these effects were attributed exclusively to the flavonoid content or to other compounds present in cocoa. To this end, eight-week-old Lewis rats were fed, for two weeks, either a standard diet or three isoenergetic diets containing increasing proportions of cocoa flavonoids from different sources: one with 0.2% polyphenols from conventional defatted cocoa, and two others with 0.4% and 0.8% polyphenols, respectively, from non-fermented cocoa. Diet intake and body weight were monitored and fecal samples were obtained throughout the study to determine fecal pH, IgA, bacteria proportions, and IgA-coated bacteria. Moreover, IgG and IgM concentrations in serum samples collected during the study were quantified. At the end of the dietary intervention no clear changes of serum IgG or IgM concentrations were quantified, showing few effects of cocoa polyphenol diets at the systemic level. However, in the intestine, all cocoa polyphenol-enriched diets attenuated the age-related increase of both fecal IgA and IgA-coated bacteria, as well as the proportion of bacteria in feces. As these effects were not dependent on the dose of polyphenol present in the diets, other compounds and/or the precise polyphenol composition present in cocoa raw material used for the diets could be key factors in this effect.
Toxicological aspects of the use of phenolic compounds in disease prevention
Zuzana Kyselova
Interdisciplinary Toxicology , 2011, DOI: 10.2478/v10102-011-0027-5
Abstract: The consumption of a diet low in fat and enhanced by fruits and vegetables, especially rich in phenolic compounds, may reduce risks of many civilization diseases. The use of traditional medicines, mainly derived from plant sources, has become an attractive segment in the management of many lifestyle diseases. Concerning the application of dietary supplements (based on phenolic compounds) in common practice, the ongoing debate over possible adverse effects of certain nutrients and dosage levels is of great importance. Since dietary supplements are not classified as drugs, their potential toxicities and interactions have not been thoroughly evaluated. First, this review will introduce phenolic compounds as natural substances beneficial for human health. Second, the potential dual mode of action of flavonoids will be outlined. Third, potential deleterious impacts of phenolic compounds utilization will be discussed: pro-oxidant and estrogenic activities, cancerogenic potential, cytotoxic effects, apoptosis induction and flavonoid-drug interaction. Finally, future trends within the research field will be indicated.
Natural Antioxidants: Function and Sources  [PDF]
Yevgenia Shebis, David Iluz, Yael Kinel-Tahan, Zvy Dubinsky, Yaron Yehoshua
Food and Nutrition Sciences (FNS) , 2013, DOI: 10.4236/fns.2013.46083
Abstract: The definition of antioxidants, given in 1995 by Halliwell and Gutteridge, stated that an antioxidant is “any substance that, when present at low concentrations compared with that of an oxidizable substrate, significantly delays or inhibits oxidation of that substrate” [1]. In 2007, Halliwell gave a more specific definition, stating that an antioxidant is “any substance that delays, prevents or removes oxidative damage to a target molecule” [2]. Oxidation reactions produce free radicals that can start multiple chain reactions that eventually cause damage or death to the cell. Antioxidants remove these free-radical intermediates by being oxidized themselves, and inhibit other oxidation reactions, thus stopping the harmful chain reactions. Such oxidative processes are dangerous for all living cells, especially those in proximity to sites where active oxygen is released by photosynthesis. Spontaneous oxidation causes food rancidity and spoilage of medicines. Furthermore, oxidative stress is an important part of many human diseases that can occur, inter alia, due to a lack of appropriate nutrition and exercise, air pollution, smoking, and more, leading to lethal diseases, such as cancer. Therefore, it is imperative to include antioxidants in our diets. Due to the fact that synthetically produced antioxidants are currently used in the food and pharmaceutical industries in order to prolong product shelf life, there is currently a strong trend to search for large, available, and efficient natural sources of antioxidants to replace the synthetic ones, thus minimizing damage to our cells.
Ufuk KARAKU?,Murat KE?E
Zeitschrift für die Welt der Türken , 2012,
Abstract: In this study, it has been analyzed that the perception of the natural environment and the importance of environmental education over the Turks in Turkish proverbs which is one of the important building blocks of folk culture. In the introduction, after a theoretical knowledge base about the natural environment and human interaction have been established, information is given about the basic concepts of the study such as Turkish culture-proverbial relationships and importance of proverbs in terms of environmental education. In other parts of the study, it has been analyzed that how they perceive Turkish vegetation, animals, climate, soil and water in terms of the environmental value based on 507 Turkish proverbs which were searched and included in the study from different sources related to the natural environment. It has been seen in the examination that Turks have great importance of proverbs that contains climate on the perception of the natural environment of the first place, and it is followed by proverbs about the climate and animals. It was put forward that the proverbs which are etched in public memory is very important in terms of environmental education.
Lignicolous fungi as potential natural sources of antioxidants
Karaman Maja A.,Mimica-Duki? Neda M.,Matavulj Milan N.
Archives of Biological Sciences , 2005, DOI: 10.2298/abs0502093k
Abstract: As a result of an interest in natural derived metabolites around the world higher fungi (Basidiomycotina) have taken on great importance in biochemical investigations. A large number of structurally divergent compounds - both cellular components and secondary metabolites - have been extracted and found to possess significant biological activity, such as an immunomodulative effect on the human body. Effects of fungal biomolecules as potential natural antioxidants have not been examined so far. Biochemical analysis have included in vitro testing of the influence of different extracts (water methanol, chloroform) of selected fungal sporocarps on Fe2+/ascorbate-induced lipid peroxidation (LP) in a lecithin liposome system by TBA assay, as well as various other procedures. Qualitative analysis by TLC revealed a distinction both between different extracts of the same fungal species and between similar extracts of different species. The results obtained on antioxidative activities (LP inhibition and "scavenging" activity) indicate that MeOH extracts manifested a degree of activity higher than that of CHCl3 extracts with respect to antioxidative activity, the extracts can be ranged in the following declining order: Ganoderma lucidum, Ganoderma applanatum Meripilus giganteus, and Flammulina velutipes. The obtained results suggest that the analyzed fungi are of potential interest as sources of strong natural antioxidants in the food and cosmetics industries, whereas synthetic ones have proved to be carcinogenic.
Evaluation of antiaggregatory activity of flavonoid aglycone series
Mirza Boji?, ?eljko Debeljak, Maja Tomi?i?, Marica Medi?-?ari?, Sini?a Tomi?
Nutrition Journal , 2011, DOI: 10.1186/1475-2891-10-73
Abstract: A set of thirty flavonoid aglycones has been selected for the evaluation. All measurements of aggregation were done under standardized and firmly controlled in vitro conditions. The whole blood samples, multiple platelet functional analyzer and adenosine diphosphate (ADP) as a weak agonist of aggregation were selected for this purpose.The results were expressed as minimal concentration of flavonoid that can significantly lower the platelet aggregation compared to the corresponding untreated sample (minimal antiaggregatory concentration - MINaAC). All analyzed flavonoids exhibited antiaggregatory activity MINaAC ranging from 0.119 μM to 122 μM, while the most potent representatives were 3,6-dihydroxyflavone (0.119 μM) and syringetin (0.119 μM).Measurable antiplatelet activity established at submicromolar flavonoid concentrations suggests that even a dietary consumption of some flavonoids can make an impact on in vivo aggregation of platelets. These findings also point out a therapeutical potential of some flavonoids.In the developed countries most of the older population is affected by cardiovascular diseases. Platelets are involved in haemostasis, thrombosis and inflammatory processes, hence as a consequence of that physiological role heart stroke and cerebrovascular insult can occur. Most commonly used drug in prevention of mentioned diseases is acetylsalicylic acid while clopidogrel represents another therapeutic option. Neither of these drugs is free of side effects, thus the search for new and safer drug from this group continues [1]. From the natural compounds, present in every day diet, polyphenols, mainly flavonoids (Figure 1), have shown beneficial effect in prevention of cardiovascular diseases [2-7]. Flavonoids naturally occur in a free form (aglycones) or bound to a sugar moiety via hydroxyl groups (glycosides).Flavonoid antiplatelet activity can be attributed to the increased production of prostacyclin by endothelian cells. Prostacyclin decreases aggrega
Adrian Grozavu,Sergiu Ple?can,Ciprian M?rg?rint
Present Environment and Sustainable Development , 2011,
Abstract: Among the methods for the evaluation of natural and anthropic risks, those of the questionnaire and Analytic Hierarchy Process (AHP) allow evidencing the exposure degree to hazards and also the assessment of factor weights in human communities’ degree of vulnerability. In the present study, the two methods have been applied in the analysis of the territory of Lep a-Gre u Depression, located in Vrancea Mountains from the Eastern Carpathians, potentially threatened by different risk phenomena, such as heavy rains, flash floods, landslides and earthquakes. The application of the questionnaire revealed a weak and diffuse perception on the risk phenomena among the population and also correlations and variations in risk perception caused by several factors, such as age and socio-economic status. AHP allowed to obtain the preference weights of the four analyzed factors in the vulnerability of the region, evidencing the higher importance of the “floods” factor in comparison to the others, and as a consequence the necessity or reorienting the efforts of developing practices and projects of risk reduction in the region
The diet of spotted cuscus (Spilocuscus maculatus) in natural and captivity habitat
Nusantara Bioscience , 2010,
Abstract: Saragih EW, Sadsoeitoeboen MJ, Pattiselanno F. 2010. The diet of spotted cuscus (Spilocuscus maculatus) in natural and captivity habitat. Nusantara Bioscience 2: 78-83. The ex-situ conservation of cuscus (Spilocuscus maculatus) under captivating condition is an alternative solution to protect cuscus from extinction. Diets became the main factor in order to support the domestication process. Particular studies on habitat and diet of cuscus have been carried out however there is still limited information on the nutrition aspects of cuscus food. This study aimed to determine the diet type, palatability and nutrient in both natural habitat and captivating condition. The results indicated that there were 19 and 8 plant species identified as cuscus diets in both natural habitat and captivating condition. Cuscus prefers fruits with astringent and sour taste which is contained high crude fiber and low fat.
Importance of Milk Consumption in the Diet of Secondary School Students in Nigeria
M.A. Belewu,G.B. Adesiji,B.M. Matanmi,O. Bolarin
Pakistan Journal of Nutrition , 2009,
Abstract: The purpose of this study was to investigate the importance of milk consumption in the diet of secondary school students in Ibadan North and Akinyele local government areas of Oyo State, Nigeria. Questionnaire was used to elicit information from the students and simple randomly sampling was used to select forty students each from public secondary schools students of urban and rural areas and also forty students from private secondary school in both rural and urban areas. The sample consisted of equal number of males and females. Frequency distributions and percentages were calculated. Student’s t-test was used to determine whether there is significant difference between milk consumption and developmental indices of students. The findings revealed that respondents’ preference was more to liquid than powdered milk while the purchasing power was also in-like manner. The private secondary school students had the highest daily consumption rate and purchasing power than the public school students. The results further revealed that there were statistical differences in height of students (both sexes) of the rural and urban secondary school students while there was no significant difference in the weight and forearms of private and the public secondary school students in both urban and rural. Milk is important in the diet of secondary school students since they are in their developmental stages of life, therefore the study recommends the introduction of school milk programme sponsored by government. Also, nutritional education should be introduced to academic curriculum of secondary school.
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