Intake of oral photoprotectors by postmen in Porto Alegre

Introduction: Postmen are daily exposed to high levels of solar radiation, and lack of protection can result in many health damages. The present study aimed to identify cutaneous phototypes and evaluate the intake of oral photoprotectors by postmen. Methods: Cross-sectional study, carried out from August 2011 to December 2012 in the city of Porto Alegre, state of Rio Grande do Sul, Brazil. Socioeconomic and behavioral data regarding daily solar exposure were collected through a questionnaire. To evaluate the intake of beta-carotene, lycopene and omega-3, two 24-hour dietary recalls were applied. Cutaneous phototypes were assessed by Fitzpatrick's classification. Results: A total of 181 postmen were analyzed, whose mean age was 40.2±11.4 years old, and 140 (77.3%) were male. The cutaneous phototypes II, III and IV were the most prevalent (n=138), totaling 76.3% of the sample. The median for the oral photoprotectors intake was 1.16 mg (0.46-2.29) of beta-carotene, 3.60 mg (1.01-6.31) of lycopene and 0.95 g (0.61-1.45) of n-3 fatty acids, all values significantly lower than the minimal doses to obtain photoprotective effect (p<0.001). The individuals in the group of phototypes V and VI showed lower adherence to the use of sunscreen and lower intake of beta-carotene, comparing to the other groups. Conclusions: The intake of oral photoprotectors is low in this population. Future studies may evaluate the real effect of oral photoprotectors, so that preventive measures using this approach can be included in photoprotection education actions for outdoor workers (AU)

Desenvolvimento de pão de forma enriquecido com batata-doce biofortificada / Development loaf of bread enriched with biofortified sweet potato

Objetivo do trabalho foi desenvolver pão de forma adicionado de polpa de batata-doce, cultivar Beauregard, e avaliar sensorialmente o produto, verificando a sua aceitação entre os consumidores. Foram desenvolvidas três formulações com substituição da farinha de trigo pela batata-doce cozida nas porcentagens de 20%, 40% e 60% e comparadas com o padrão, sem substituição. A avaliação sensorial foi feita por 32 provadores, não treinados, utilizando-se escala hedônica para os atributos de sabor, cor, textura, aroma e aceitação global. Os pães de forma elaborados com a batata-doce não apresentaram diferença estatística na análise sensorial para os atributos avaliados. Os pães obtiveram notas relevantes, com boa aceitação entre os consumidores. Em relação ao sabor, as melhores notas foram dadas para a amostra com 20% de substituição de farinha de trigo por batata-doce, comparada com a amostra, sem substituição de farinha de trigo. O aroma dos pães foi destaque também nas amostras com maior porcentagem de substituição, 60% e 40%. Para os demais atributos não houve diferença significativa em relação à amostra padrão, com 100% de farinha de trigo, o que permitiu concluir que a adição de batata-doce com polpa laranja na formulação de pão de forma pode ser considerada uma opção saudável de consumo de alimento biofortificado para combater a "fome oculta", que é a carência dos micronutrientes vitamina A, ferro e zinco, essenciais para a saúde.

The objective was to develop a loaf of bread with sweet potato pulp, Beauregard, evaluate the product by sensory analysis and verify their acceptance among consumers. Three formulations were developed to replace the wheat flour for sweet potatoes baked in percentages of 20%, 40% and 60%, compared with the standard, without replacement. The sensory evaluation was performed by 32 panelists, untrained, using hedonic scale for the attributes of flavor, color, texture, aroma and global acceptance. The loaf of breads elaborate with sweet potato showed no statistical difference in sensory analysis for the evaluated attributes. The breads obtained relevant notes, with good acceptance among consumers. Regarding the taste, the best grades were given for the sample with 20% wheat flour substitute for sweet potatoes, compared with the sample without wheat flour replacement. The aroma of bread was also featured in the samples with the highest percentage of replacement, 60% and 40%. For other attributes there was no significant difference from the standard sample, 100% wheat flour, which showed that the addition of sweet potatoes with orange pulp in the form of bread formulation can be considered a healthy option consumption biofortified of food to fight "hidden hunger", which is the lack of micronutrients vitamin A, iron and zinc, essential for health.

Protection against photooxidative damage provided by enzymatic and non-enzymatic antioxidant system in sorghum seedlings.

Effect of photoinhibition of sorghum leaves and isolated chloroplasts on chlorophyll fluorescence, peroxidation of thylakoid lipids and activity of antioxidant enzymes were studied. Photoinhibition of intact leaves and isolated chloroplasts decreased Fv/Fm ratio and qP, while qN increased. Photoinhibitory damage was more at 5 degrees C than at 30 degrees or 50 degrees C. Peroxidation of thylakoid lipids was 5 times greater when photoinhibited at 50 degrees C compared to control. Photoinhibition of chloroplasts under low oxygen condition or when supplemented with anti-oxidants (beta-carotene, ascorbate and GSH) resulted in significantly less damage to photosynthesis (Fv/Fm ratio) and peroxidation level. Photoinhibition also resulted in many fold increase in the activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) and decrease in catalase. Data presented here suggest that photoinhibition resulted in production of oxygen radicals and photoinhibition of chloroplasts in the presence of low oxygen level or when supplemented with antioxidants decreased the damage to Fv/Fm ratio and peroxidation level to a great extent since former prevented the formation of oxygen radicals and later could scavenge the oxygen radicals thus the protection. Increase activity of SOD and APX may also be to metabolise the oxygen radicals produced during photoinhibition treatment, thereby, protecting the seedlings against photooxidative damage.

Antioxidantes: mitos y realidades / Antioxidants: myths and reallity

La homeostasis de los seres vivos aeróbicos se ve constantemente amenazada por la formación de moléculas químicamente inestables y altamente reactivas llamadas radicales libres. Estos pueden generarse por agresores metabólicos endógenos (metabolismo celular) o exógenos, como el tabaco, el ozono y la radiación ultravioleta. Se les relaciona con una serie de condiciones patológicas, como la carcinogénesis, la aterosclerosis y el envejecimiento tisular. Los antioxidantes son sustancias que al interactuar con estos radicales libres previenen o demoran su acción deletérea. En la dieta se encuentran diversos compuestos que pueden contribuir a la modulación interna de los antioxidantes, apartándolos en forma directa o como cofactores. Es importante conocer estos antioxidantes dietarios, saber sus requerimientos mínimos y los potenciales riesgos por uso inapropiado

Current controversies in carotene nutrition.

Most of the dietary vitamin A is derived from plant foods in the form of pro-vitamin A, the carotenoids. Though in 1930 it was first demonstrated that beta-carotene is the precursor for vitamin A and it is well accepted that 1 mole of beta-carotene is equivalent to one mole of vitamin A, the mechanism of conversion to vitamin A has been controversial. Some of the mechanisms suggested are central cleavage potentially yielding 2 molecules of vitamin A or excentric cleavage producing one molecule of vitamin A from beta-carotene which drastically varied the potency of carotene. A mucosal supernatant from rat intestine was shown to have beta-carotene dioxygenase activity which provided the basis for central cleavage. Many observations on enzyme activity in vitro and efficacy of carotene in vivo did not support the above findings and a re-evaluation of the whole problem was undertaken at the National Institute of Nutrition (NIN), Hyderabad. Intestinal conversion of beta-carotene to vitamin A both in vitro and in vivo in rats and in vivo in children was evaluated. A novel method of obtaining the in vivo conversion of carotene to vitamin A using the ratio of area under plasma vitamin A time curves after a dose of beta-carotene and vitamin A (> 100 micrograms) was developed in rats and later extended to children. In children a dose of 1.5 mg of beta-carotene and vitamin A was used. From these studies intestinal conversion of beta-carotene to vitamin A was found to be an enzymatic reaction involving central cleavage and which needed the presence of oxygen. The substrate was found to bind the enzyme at C-15,15'. The enzyme may be associated with inherent or contaminant enzyme which breaks of other part of the molecule released after central cleavage of carotene. The in vivo conversion of carotene to vitamin A was found to vary from 20 to 80 per cent depending on the nutritional status. Vitamin A deficiency was found to enhance both the in vitro and in vivo conversion and protein deficiency to decrease both. Thus the present results confirm the convertibility of dietary carotenoids to vitamin A and could facilitate further investigations on interactions of different dietary carotenoids on the absorption and cleavage of carotene to vitamin A in children.