β-carotene and other carotenoids as antioxidants

Carotenoids are natural pigments which are synthesized by plants and are responsible for the bright colors of various fruits and vegetables. There are several dozen carotenoids in the foods that we eat, and most of these carotenoids have antioxidant activity. β-carotene has been best studied since, in most countries it is the most common carotenoid in fruits and vegetables. However, in the U.S., lycopene from tomatoes now is consumed in approximately the same amount as β-carotene. Antioxidants (including carotenoids) have been studied for their ability to prevent chronic disease. β-carotene and others carotenoids have antioxidant properties in vitro and in animal models. Mixtures of carotenoids or associations with others antioxidants (e.g. vitamin E) can increase their activity against free radicals. The use of animals models for studying carotenoids is limited since most of the animals do not absorb or metabolize carotenoids similarly to humans. Epidemiologic studies have shown an inverse relationship between presence of various cancers and dietary carotenoids or blood carotenoid levels. However, three out of four intervention trials using high dose β- carotene supplements did not show protective effects against cancer or cardiovascular disease. Rather, the high risk population (smokers and asbestos workers) in these intervention trials showed an increase in cancer and angina cases. It appears that carotenoids (including β-carotene) can promote health when taken at dietary levels, but may have adverse effects when taken in high dose by subjects who smoke or who have been exposed to asbestos. It will be the task of ongoing and future studies to define the populations that can benefit from carotenoids and to define the proper doses, lengths of treatment, and whether mixtures, rather than single carotenoids (e.g. β-carotene) are more advantageous.

Edible coatings from native and modified starches retain carotenoids in pumpkin during drying

The goal of this study was to evaluate the effect of edible coating pre-treatments on the retention of provitamin A during pumpkin drying. The coatings used were based on native and modified maize and cassava starch. To evaluate the effects of these coatings, slices of 'Dry Rajada' pumpkin were dried at 70 °C both with and without starch coatings applied at 30 and 80-90 °C. Carotenoid content was determined through HPLC using a C 30 column. Significant losses (12-15%) of trans-α-carotene and trans-β-carotene were observed when slices were dried without the coating. Significant improvement of carotenoid content was observed for dehydrated slices that were previously coated with a native maize starch solution at 90 °C, as well as with a modified maize starch solution at 30 °C and also with a modified cassava starch solution at 90 °C. The application of these starch solutions probably produced a more uniform film that adhered to the slices, minimizing carotenoid degradation during pumpkin drying and, as a consequence, resulting in a product that can be considered a good source of provitamin A. © 2012 Elsevier Ltd.

Antioxidant activity and determination of total phenol contents, carotenoids, beta-carotene, lycopene and zinc in white, yellow and pinkish varieties of manihot esculenta crantz

There are cassava varieties that present compounds as carotenoids, beta-carotene, lycopene and minerals important for human and animal health. The present study evaluated the antioxidant activity of the white, yellow and pinkish varieties of Manihot esculenta, by mean of the DPPH test and by the ferrous ion-chelating activity. Furthermore, the total phenols, carotenoids, beta-carotene, lycopene and zinc contents were also determined. Utilizing the DPPH test it was possible to find that extracts of boiled samples presented higher antioxidant activity (89.53% -pinkish) in comparison to the fresh samples (1.97% -white). For the ferrous ion-chelating test, the highest activity was found for the boiled pinkish variety extract (63.43%) and the lowest was for fresh yellow extract (17.34%) the white sample did not present activity. The highest concentration of total phenols and zinc content was obtained for the boiled pinkish variety extract 136.12 mg EAG/g of extract and 0,811ppm, respectively, in the concentration of 1000 mu g/mL. The pinkish variety presented also higher quantity of pigments, including carotenoid (29.40 mu g/g), beta-carotene (9.14 mu g/100g) and lycopene (68.92%). According to the results obtained in this study it was possible to conclude that the yellow and pinkish varieties of M. esculenta present quantity of phenolic compounds and minerals sufficient to attribute the antioxidant activity and may thus contribute to reduce oxidative damage and be used as nutraceuticals or directly ingested in the diet to maintain good health.

Phenolic compounds, carotenoids, tocopherols and fatty acids present in oils extracted from palm fruits

This review aimed to discuss the main bioactive compounds present in oils extracted from palm trees, indicating possible applications for the same. The bioactive compounds approached were: phenolic compounds, carotenoids, tocopherols, mono and polyunsaturated fatty acids. It is growing the search for food, especially from plant origin, characterized by the presence of such substances due to their benefi ts. Many studies show palm species as important sources of bioactive compounds and essential fatty acids. Therefore it is important to study the fruit characterization and composition of the oil from palm species of different regions that are still poorly investigated, seeking the possibility of its application in industry or the development of functional foods.

Stability of Carotenoids, Total Phenolics and In Vitro Antioxidant Capacity in the Thermal Processing of Orange-Fleshed Sweet Potato (Ipomoea batatas Lam.) Cultivars Grown in Brazil

Intervention strategies regarding the biofortification of orange-fleshed sweet potato, which is a rich source of carotenoids for combating vitamin A deficiency, are being developed in Brazil. This study was conducted to evaluate the concentrations of individual carotenoids, total phenolic compounds and antioxidant capacity in the roots of four biofortified sweet potato cultivars that were raw or processed by four common heat treatments. HPLC, Folin-Ciocalteu, DPPH and ABTS assays were used. All cultivars showed high levels of carotenoids in raw roots, predominantly all-trans-beta-carotene (79.1-128.5 mg.100 g(-1) DW), suggesting a high estimated vitamin A activity. The CNPH 1194 cultivar reported carotenoids values highest than those of other cultivars (p < 0.05). The total phenolic compounds varied among cultivars and heat treatments (0.96-2.05 mg.g(-1) DW). In most cases, the heat treatments resulted in a significant decrease in the carotenoids and phenolic compounds contents as well as antioxidant capacity. Processing of flour presented the greatest losses of major carotenoids and phenolics. The phenolic compounds showed more stability than carotenoids after processing. There were significant correlations between the carotenoids and phenolic compounds and the antioxidant capacity.

Carotenoids and polyphenols in nutricosmetics, nutraceuticals, and cosmeceuticals

The market for cosmeceuticals continues with significant annual growth, but today consumers are more aware of nutritional products that contribute to both skin health and disease prevention. In the last 10 years, pharmacists, chemists, nutritionists, and physicians have been working together to develop new nutritional applications to satisfy peoples needs and demands. As a recent result of convergence phenomenon between cosmetics and food industries, nutricosmetics is a blurry area unfamiliar to many consumers and sometimes even to foods and cosmetics experts. Characterized by oral supplementation of nutrients, nutricosmetics are also known as beauty pills,beauty from within, and even oral cosmetics. The major claim is the antiaging effect, reducing wrinkles by fighting free radicals generated by solar radiation. Among the ingredients used in nutricosmetics, antioxidants represent the most crucial. The best-known antioxidants are carotenoids (beta-carotene, lycopene, lutein, zeaxanthin, and astaxanthin) and polyphenols (anthocyanidins, catechins, flavonoids, tannins, and procyanidins). This study presents an overview about the concept of nutricosmetics and gives us information about the difference between nutricosmetics, nutraceuticals, and cosmeceuticals. The article also discusses about carotenoids and polyphenols, two classes of ingredients often employed in such products.

Combined levels of carotenoids and vitamin E in diets for gilthead seabream broodstocks (Sparus aurata L.): effect on the quality of egg spawning and composition

Watanabe et al. (1991 a,b) state that, vitamin E and carotenoids perform an essential role on the quality of egg spawning. Vitamin E is one of the main nutrients for the reproduction of fish (Izquierdo et al., 2001), and it has been proved that its inclusion in diets for broodstocks favors the quality of egg spawning in several species of fish (Watanabe and Takashima,1977; Takeuchi et al., 1981; Watanabe et al., 1985, 1991 a,b; Sutjaritvongsanon, 1987; Watanabe, 1990; Schimittou, 1993; Mushiake et al., 1993; Dube, 1996; Shiranee and Natarajan, 1996; Izquierdo et al., 2001; Morehead et al., 2001; Fernández- Palacios et al., 2005). On the other hand, the carotenoids which also perform an antioxidizing function (including the protection of lipids from oxidation), have been involved in the reproductive processes of marine organisms: crustaceans (Liñan-Cabello et al., 2002), marine fish (Watanabe y Kiron, 1995; Verakunpiriya et al., 1997 a,b; Vassallo-Agius et al., 2001 a,b,c, 2002; Watanabe and Vassallo-Agius 2003) and fresh water fish (Ahmadi et al., 2006). The results of this study suggest that the recommended levels of n-3 HUFA in diets for gilthead sea bream broodstocks could be increased up to 3,5 % when supplemented jointly with carotenoids from paprika oleoresin and vitamin E, thus favoring the quality of spawning.

Cellular immune response, stress resistance and competitiveness in nestling great tits in relation to maternally transmitted carotenoids

1. Egg yolks contain carotenoids that protect biological molecules against free-radical damage and promote maturation of the immune system. Availability of carotenoids to birds is often limited. Trade-offs can thus arise in the allocation of carotenoids to different physiological functions, and mothers may influence the immunocompetence of nestlings by modulating the transfer of carotenoid to the yolk.;2. In the great tit Parus major, we experimentally manipulated the dietary supply of carotenoid to mothers, and partially cross-fostered hatchlings to investigate the effect of an increased availability of carotenoids during egg laying on immunocompetence of nestlings.;3. In addition, we infested half of the nests with hen fleas Ceratophyllus gallinae to investigate the relationship between carotenoid availability, resistance to ectoparasites and immunocompetence.;4. We found that the procedure of cross-fostering can reduce the immune response of nestlings, but this effect can be compensated by the maternally transferred carotenoids. Cross-fostered nestlings of carotenoid-supplemented females show a similar immune response to non-cross-fostered nestlings, while cross-fostered nestlings of control females mounted a weaker cell-mediated immune response. This suggests that yolk carotenoids may help nestlings to cope with stress, for example the one generated by cross-fostering and/or they may enhance nestling competitiveness.;5. There was no statistically significant interaction between parasite and carotenoid treatments, as would be expected if carotenoids helped nestlings to fight parasites. Under parasite pressure, however, lighter nestlings raised a lower immune response, while the immune response was only weakly correlated with body mass in uninfested nests.

Carotenoid-based plumage colors and immune function: Is there a trade-off for rare carotenoids?

Theory suggests that carotenoid-based signals are used in animal communication because they contain specific information about parasite resistance or immunocompetence. This implies that honesty of carotenoid-based signals is maintained by a trade-off between pigmentation and immune function for carotenoids, assuming that the carotenoids used for coloration are also immunoenhancing. We tested this hypothesis by altering the diets of nestling great tits (Paris major) with supplementary beadlets containing the carotenoids that are naturally ingested with food or beadlets containing the carotenoids that are incorporated into the feathers; a control group received beadlets containing no carotenoids. We simultaneously immune challenged half of the nestlings of each supplementation group, using a two-factorial design. Activatior of the immune system led to reduced color expression. However, only nestlings fed with the naturally ingested carotenoids and not with the carotenoids deposited in the feathers showed an increased cellular immune response. This shows that the carotenoids used for ornamentation do not promote the immune function, which conflicts with the trade-off hypothesis. Our results indicate that honesty of carotenoid-based signals is maintained by an individual's physiological limitation to absorb and/or transport carotenoids and by access to carotenoids, indicating that preferences for carotenoid-based traits in sexual selection or parent-offspring interactions select for competitive individuals, rather than specifically for immune function.

The effect of specific carotenoids on lung cancer risk

A population-based case-comparison study of histologically confirmed lung cancer among white male and female residents of six Texas coastal counties was conducted from 1979-1982. Dietary information as well as information concerning smoking, alcohol consumption, occupational and residential exposures, and family history of cancer was obtained from 149 living cases and 359 comparison subjects.^ These data support the findings of previous studies that reported a protective association of total carotene intake with lung cancer (OR = 4.07, CI = 3.36-4.78), and no association for total Vitamin A or retinol. Of six specific carotenoids examined, these data reveal a statistically significant protective effect for alpha carotene (OR = 3.58, CI = 2.85-4.31), and an elevated, although non-significant effect for beta carotene (OR = 1.46, CI = 0.61-2.31). No consistent significant effect was found for cryptoxanthin, other xanthins, lutein or lycopene.^ Similar results were found for both males and females, and for both squamous cell and adenocarcinoma subtypes, although loss of power resulting from stratification may have rendered the celltype specific results more imprecise. These results should be considered with caution until confirmed by other studies, however, they suggest the importance of evaluating specific carotenoids in future diet-lung cancer investigations. ^

(Table 1) Chlorophyll concentration and pigment composition of carotenoids in three heathland bryophytes, northern Sweden

Background and Aims: Anthropogenic depletion of stratospheric ozone in Arctic latitudes has resulted in an increase of ultraviolet-B radiation (UV-B) reaching the biosphere. UV-B exposure is known to reduce aboveground biomass and plant height, to increase DNA damage and cause accumulation of UV-absorbing compounds in polar plants. However, many studies on Arctic mosses tended to be inconclusive. The importance of different water availability in influencing UV-B impacts on lower plants in the Arctic has been poorly explored and might partially explain the observed wide variation of responses, given the importance of water in controlling bryophyte physiology. This study aimed to assess the long-term responses of three common sub-Arctic bryophytes to enhanced UV-B radiation (+UV-B) and to elucidate the influence of water supply on those responses. Results: Responses were species specific: H. splendens responded most to +UV-B, with reduction in both annual growth (-22%) and sporophyte production (-44%), together with increased b-carotene, violaxanthin, total chlorophyll and NPQ, and decreased zeaxanthin and de-epoxidation of the xanthophyll cycle pool (DES). Barbilophozia lycopodioides responded less to +UV-B, showing increased b-carotene and sclerophylly and decreased UV-absorbing compounds. Polytrichum commune only showed small morphogenetic changes. No effect of UV-B on bryophyte cover was observed. Water availability had profound effects on bryophyte ecophysiology, and plants showed, in general, lower growth and ETR, together with a higher photoprotection in the drier site. Water availability also influenced bryophyte responses to +UV-B and, in particular, responses were less detectable in the drier site. Conclusions: Impacts of UV-B exposure on Arctic bryophytes were significant, in contrast to modest or absent UV-B effects measured in previous studies. The impacts were more easily detectable in species with high plasticity such as H. splendens and less obvious, or more subtle, under drier conditions. Species biology and water supply greatly influences the impact of UV-B on at least some Arctic bryophytes and could contribute to the wide variation of responses observed previously.