A composição de minerais foi investigada em 154 amostras de pólen apícola, provenientes de diferentes regiões do Brasil. A técnica de ICP OES foi utilizada para determinar Ca, Cu, Fe, K, Mg, Mn, Na, P, Se e Zn, após mineralização em sistema de microondas. Utilizando parâmetros instrumentais otimizados conseguiu-se boa exatidão e precisão na determinação simultânea dos minerais. Em geral, as amostras dos estados do Nordeste apresentaram teores de minerais mais elevados e produção constante durante o ano. Os minerais Mn, Se, Cu, Zn, Fe são os que poderiam ter maior contribuição na dieta, podendo atingir 70, 37, 27, 17 e 17%, respectivamente, da ingestão dietética diária recomendada no Brasil. A análise de componentes principais mostrou que Ca, Cu, Fe, K, Mg, Mn, Na, P e Zn podem ser usados na classificação do pólen nacional em função da origem geográfica. Os teores dos minerais variaram amplamente ao longo do ano.

The mineral composition of bee pollen was investigated in 154 samples from different Brazilian regions. Ca, Cu, Fe, K, Mg, Mn, Na, P, Se and Zn were determined by ICP OES after microwave mineralization. Employing optimized instrumental parameters, the method was shown to have a good precision and accuracy for the simultaneous determination of minerals. Overall, samples from the Northeastern states presented significantly higher amounts of minerals and showed constant production throughout the year. Manganese, Se, Cu, Zn and Fe were the elements that showed the greatest possible contributions to the diet, contributing with 70, 37, 27, 17 and 17%, respectively, of the Brazilian recommended daily intake. Principal component analysis (PCA) was applied to study geographic effects. The elements Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn were important in explaining the classification of pollen according to their geographical origin. The mineral levels varied widely during the year.

Sequential statistical methods were used to maximise carotenoid production by a strain of Rhodotorula mucilaginosa, isolated from the Brazilian ecosystem. Initially, a factorial 2(5-1) experimental design was used, and the variables were pH and the levels of glucose, yeast extract, MgSO4.7H2O and KH2PO4. The nitrogen source (yeast extract) was the most important variable in enhancing carotenoid production; MgSO4.7H2O and KH2PO4 had a negative influence. The initial pH had no significant effect on carotenoid and cell productions. We further investigated the effects of glucose and yeast extract effects, using a second-order central composite design (CCD) to optimise carotenoid production, which was adequately approximated with a full quadratic equation obtained from a two-factor-2-level design. The analysis of quadratic surfaces showed that after 5 days of cultivation at 25ºC, the maximum carotenoid concentration (745 µg l-1) was obtained with 15 g l-1 of yeast extract and 20 g l-1 of glucose. The maximum carotenoid production (152 µg g-1) was obtained with 5 g l-1 yeast extract and 10 g l-1 glucose. Carotenoid formation was more sensitive to changes in yeast extract concentration than to changes in glucose concentration. Maximum cell production was achieved with 15-17 g l-1 of yeast extract and 15-20 g l-1 of glucose.

Este estudo foi realizado para obter mais informações sobre as propriedades físico-químicas, composição e atividade antioxidante de frutos de pitanga (Eugenia uniflora L.), especialmente os do Rio Grande do Sul (Brasil). Foram comparadas pitangas com diferentes colorações de polpa (roxa, vermelha e laranja) de seleções cultivadas na Embrapa Clima Temperado (RS-Brasil). Foram observadas pequenas diferenças nos parâmetros de qualidade e na composição centesimal e de ácidos graxos entre as frutas com diferentes colorações de polpa. Os extratos de pitanga roxa apresentaram maiores conteúdos totais de fenólicos e de antocianinas, bem como, a maior capacidade antioxidante. A capacidade antioxidante (valores de DPPH e FRAP) dos extratos metanólicos de pitanga apresentou alta correlação com o conteúdo de fenólicos totais, mas nos extratos etanólicos, o conteúdo de antocianinas correlacionou-se apenas com a capacidade antioxidante avaliada pelo método de FRAP. A pitanga de cor laranja apresentou maiores teores de β-criptoxantina e β-caroteno, enquanto que a de cor vermelha continha alto teor de licopeno. Os resultados indicam que a pitanga de cor roxa, cultivada no Rio Grande do Sul, é uma fonte rica de compostos fenólicos e possui alta capacidade antioxidante. As de cor vermelha e laranja, por outro lado, são fontes ricas de carotenoides.

This study was carried out to obtain more information about the physicochemical properties, composition, and antioxidant activity of pitanga fruits (Eugenia uniflora L.), particularly fruits from the State of Rio Grande do Sul, Brazil. Pitanga with different flesh colors (purple, red, and orange) from tree selections cultivated at Embrapa Clima Temperado (RS-Brazil) were analyzed. Only slight differences were observed in the quality parameters and in the proximate and fatty acid compositions among the fruits studied. The extracts from purple-fleshed pitanga had the highest total phenolic and anthocyanin contents along with the highest antioxidant capacity. The antioxidant capacity (DPPH and FRAP assays) of methanolic pitanga extracts was highly correlated with the total phenolic content, but in ethanolic extracts, the anthocyanin content was correlated only with the FRAP antioxidant capacity. Orange fleshed pitanga had higher β-cryptoxanthin and β-carotene levels than those of the red fruit, which had higher lycopene content. The results indicate that the purple-fleshed pitanga, cultivated in Rio Grande do Sul, is a rich source of phenolic compounds and has high antioxidant capacity. The red and orange-fleshed pitanga, on the other hand, are rich sources of carotenoids.

This work optimized the HPLC conditions for the simultaneous determination of luteolin, apigenin, myricetin, quercetin and kaempferol in aglycone form, as well defined the best conditions for hydrolysis/extraction of these flavonoids in fruits, using the statistical central composite design and response surface analysis. A reverse phase method was developed using a gradient of methanol/water acidified with 0.3% formic acid as mobile phase and a photodiode array detector. The samples were extracted with methanol/water (50:50 v/v) at 90 ºC. The optimum time and HCl concentration varied for the different fruits investigated, demonstrating the necessity of optimizing these conditions for each fruit analyzed. Good recovery (87.1 to 96.3%), repeatability and linearity were obtained.

Os carotenóides são pigmentos naturais, responsáveis pela cor em muitos alimentos como frutas e vegetais, gema de ovo, pele e músculo de alguns peixes. Porém, sua importância também está relacionada a funções ou ações biológicas nos seres humanos, como atividade pró-vitamínica A, fortalecimento do sistema imunológico, diminuição do risco de doenças degenerativas como câncer, doenças cardiovasculares, degeneração macular e catarata. A determinação da composição de carotenóides em alimentos, portanto, é considerada prioritária mundialmente. O objetivo do presente estudo foi analisar quantitativamente, por cromatografia líquida de alta eficiência, os principais carotenóides presentes em três cultivares de mamão (Formosa, Golden e Sunrise) e três cultivares de pêssego (Xiripá, Coral e Diamante). Para cada cultivar, foram analisados cinco lotes durante o ano para mamão e durante a safra para pêssego. Os três cultivares de mamão apresentaram composição parecida com as médias dos conteúdos totais de licopeno, beta-criptoxantina e beta-caroteno variando de 18,5 a 23,9, 8,2 a 11,7 e 0,5 a 1,2 µg.g -1, respectivamente. Em relação ao pêssego, os cultivares Coral e Xiripá tiveram níveis muito baixos de carotenóides. O cultivar Diamante teve um teor total médio de 6,4 µg.g -1 de beta-criptoxantina, o carotenóide principal.

Carotenoids are natural pigments responsible for the color of many foods such as fruit, vegetables, egg yolk, skin and the flesh of some fish. However, its importance is also related to biological functions or actions in humans, such as the provitamin A activity, enhancement of the immune system, reduction of the risk of degenerative diseases, such as cancer, cardiovascular diseases, macular degeneration and cataract. The determination of the carotenoid composition of foods is therefore considered a priority worldwide. The objective of the present study was to analyze quantitatively, by high performance liquid chromatography, the principal carotenoids of three cultivars of papaya (Formosa, Golden and Sunrise) and three cultivars of peach (Xiripá, Coral and Diamante). For each cultivar, five sample lots were analyzed, collected during the year for papaya and during the season for peach. The three papaya cultivars had a similar composition, the mean total contents of lycopene, beta-cryptoxanthin and beta-carotene varied from 18.5 to 23.9, 8.2 to 11.7 and 0.5 to 1.2 µg.g -1, respectively. In relation to peach, the cultivars Coral and Xiripá had very low levels of carotenoids. The cultivar Diamante had a mean total content of 6.4 µg.g -1 of beta-cryptoxanthin, the major carotenoid.

No presente estudo, foram determinados os teores de catequinas e teaflavinas em três marcas de chá verde e quatro de chá preto comercializadas no Brasil. A metodologia analítica consistiu de extração aquosa bastante simples e cromatografia líquida de alta eficiência. Foi utilizada uma coluna de fase reversa Novapak C18 (3,9 mmx150 mm, 4 µm) com um gradiente de água e metanol ambos em ácido fórmico como fase móvel. Em chás verdes, os conteúdos de catequinas (em mg/g de folha seca) variaram substancialmente: catequina, 0,8 a 2,8; epigalocatequina, 8 a 44; epigalocatequina galato, 11 a 50; epicatequina, 2,3 a 8,5 e epicatequina galato, 3,1 a 7,3. No caso dos chás pretos, as concentrações (mg/g de folha seca) de catequinas estiveram nas faixas de: 10 a 50 de epigalocatequina, 14 a 37 de epigalocatequina galato, 5 a 9 de epicatequina e 10 a 21 de epicatequina galato. As teaflavinas apresentaram variação menor: entre 5 (para teaflavina 3'-galato) e 13 mg/g (para teaflavina 3,3'-digalato) de folha seca. Amostras de chás muito consumidas no Brasil (erva doce, camomila, erva cidreira, hortelã, boldo, mate, erva mate, maçã e morango) também foram investigadas, não sendo encontrada nenhuma catequina ou teaflavina.

In the present study, the catechin and theaflavin levels in three brands of green tea and four brands of black tea commercialized in Brazil were determined. The analytical methodology consisted of a very simple aqueous extraction and high performance liquid chromatography. A reverse phase Novapak C18 (3.9 mmx150 mm, 4 µm) column was used with a gradient of water and methanol, both in formic acid, as mobile phase. In green tea, the catechin contents (in mg/g of dry leaf) varied substantially: catechin, 0.8 to 2.8; epigallocatechin, 8 to 44; epigallocatechin gallate, 11 to 50; epicatechin, 2.3 to 8.5; and epicatechin gallate, 3.1 to 7.3. In the case of black tea, the concentrations (mg/g of dry leaf) of catechins were in the ranges of: 10 to 50 of epigallocatechin, 14 to 37 of epigallocatechin gallate, 5 to 9 of epicatechin and 10 to 21 of epicatechin gallate. The theaflavins had less variation: between 5 (for theaflavin 3'-gallate) to 13 mg/g (for theaflavin 3,3'-digallate) of dry leaf. Samples of teas widely consumed in Brasil (anise, camomile, lemon grass, peppermint, boldo, maté, green maté, apple and strawberry) were also investigated but no catechin or theaflavin was detected.

Os teores de miricetina, quercetina e kaempferol foram determinados em uma marca de ban-chá, duas de chá verde e quatro de chá preto. Analisaram-se três lotes para cada marca em duplicata por cromatografia líquida de alta eficiência. Quercetina (2,5-3,4 mg/g folha seca) predominou em todas as amostras, seguida por kaempferol (1,0-2,0 mg/g folha seca), com exceção de uma amostra na qual kaempferol e miricetina tiveram teores iguais. Houve variação entre os tipos de chás e mesmo entre marcas do mesmo tipo. Miricetina (traços - 1,9 mg/g folha seca) foi o flavonol, que mais variou e que esteve em menor nível nos chás pretos. Outros chás muito consumidos no Brasil também foram investigados. A miricetina não foi encontrada em chás de frutas (maçã e morango) e de ervas (erva doce, camomila, erva cidreira, hortelã, boldo, mate e erva mate), enquanto que quercetina foi encontrada em quatro chás (camomila, boldo, morango e erva mate) e kaempferol, em dois chás (boldo e erva-mate), em concentrações de 0,4 a 2,5 e 0,4 a 2,6 mg/g de folha seca, respectivamente. Concluiu-se que estes chás são fontes de flavonóis na dieta brasileira, embora com teores menores que em chás verde e preto.

The myricetin, quercetin and kaempferol contents of a brand of "ban-chá", two brands of green tea and four brands of black tea were determined. Three lots of each brand were analysed in duplicate by high performance liquid chromatography. Quercetin (2.5-3.4 mg/g of dry leaf) predominated in all samples, followed by kaempferol (1.0-2.0 mg/g of dry leaf), with the exception of one sample, in which kaempferol and myricetin had the same levels. There was variation between different types of tea and even between brands of the same type of tea. Myricetin (trace-1.9 mg/g of dry leaf) was the flavonol, that varied the most and was present at lower levels in black tea. Other teas widely consumed in Brazil were also investigated. Myricetin was not found in teas of fruits (apple and strawberry) and herbs (anise, camomile, lemon grass, peppermint, boldo, maté, green maté), but quercetin was found in four teas (camomile, boldo, strawberry, green maté) and kaempferol, in two teas (boldo, green maté) at concentrations of 0.4 to 2.5 mg/g and 0.4 to 2.6 mg/g of dry leaf, respectively. It is concluded that these teas are sources of flavonols in the Brazilian diet, although at levels lower than those of green and black tea.

O licopeno é uma das importantes substâncias naturais de coloração industrial de alimentos. Além disso, este carotenóide tem importância em saúde humana pela sua atuação na redução de riscos de doenças crônicas como câncer, em especial de próstata, e doenças cardiovasculares. No entanto, pelo alto grau de insaturação, o licopeno é propenso à isomerização e oxidação. Neste trabalho a microencapsulação do licopeno foi estudada, utilizando as ciclodextrinas (CDs) como substâncias encapsulantes. Extraído da goiaba e isolado em coluna aberta, o licopeno dissolvido em acetona foi adicionado a alfa-, beta- e gama-CD dissolvidas em água, a acetona sendo posteriormente eliminada com auxílio de nitrogênio. Inicialmente, foi investigada a complexação com as três CDs em razão molar licopeno:CD de 1:50. O licopeno formou complexo com alfa beta- e a gama-CD, mas não com a alfa-CD. Após 180 dias de estocagem a temperatura de refrigeração (15ºC), o licopeno se manteve constante no complexo licopeno-gama-CD e reduziu cerca de 80% no complexo licopeno-beta-CD. Avaliando a melhor razão molar licopeno-CD, a inclusão foi máxima com o emprego da gama-CD e quando a razão molar foi de 1:200. O complexo mostrou-se dispersível em água, mantendo a cor vermelha do licopeno. A estabilidade à luz, mostrou-se excelente, tendo 100% de retenção em 40 dias de monitoramento a temperatura ambiente.

Lycopene is one of the important natural substances for industrial coloring of foods. In addition, this carotenoid has importance in human health because of its role in reducing the risk of chronic diseases such as cancer, especially prostate cancer, and cardiovascular diseases. However, because of its high degree of insaturation, it is prone to isomerization and oxidation. In this work, microencapsulation of lycopene was studied, utilizing cyclodextrins (CDs) as encapsulating substances. Extracted from guava and isolated in open column, lycopene in acetone was added to the alpha-, beta-, and gamma-CD dissolved in water, acetone being subsequently eliminated with nitrogen. Initially, complexation was investigated with the three CDs at a molar ratio of 1:50. Lycopene formed complexes with beta- and gamma-CD, but not with alpha-CD. After 180 days of storage at refrigeration temperature, lycopene levels remained constant in the lycopene-gamma-CD complex, but were reduced by 80% in the lycopene-beta-CD complex. During evaluation of the best molar ratio of lycopene-CD, inclusion was maximum with gamma-CD at a molar ratio of 1:200. The complex was dispersible in water, maintaining the red color of lycopene. Stability under light exposure was excellent, retention being 100% during 40 days of monitoring at ambient temperature.

O uso de microalgas e cianobactérias como fontes de nutrientes e substâncias bioativas para alimentos e suplementos alimentares vem despertando grande interesse nos últimos anos. Por meio de cromatografia em coluna aberta com espectrofotometria de absorção, cromatografia líquida de alta eficiência com detector de conjunto de diodos, cromatografia em camada delgada e reações de grupos funcionais, foram identificados trans-e cis-²-caroteno, equininona, ²-criptoxantina,3-hidroxi-4'-cetocarotenóide, zeaxantina e 3,3-diidroxi-4'-cetocarotenóide em Synechocystis pevalekii. A cianobactéria Synechocystis pevalekiiapresentou-se verde em condições normais de cultivo devido à presença de clorofilas. Com o cultivo em condições de "stress" (redução de 80% dos nutrientes do meio Conway original), as clorofilas desapareceram e a cianobactéria apresentou coloração laranja. O ²-caroteno diminuiu de 307 para 248 µg/g e a ²-criptoxantina de 94 para 13 µg/g.Por outro lado, a zeaxantina aumentou de 29 para 220 µg/g. S. pevalekii, portanto, apresenta potencial comercial como fonte de zeaxantina, carotenóide apontado como responsável pela ação protetora contra a degeneração macular e catarata, junto com a luteína. Os resultados demonstram que as condições de produção da cianobatéria podem ser estabelecidas de tal forma que a biossíntese de carotenóides importantes para saúde humana, de difícil obtenção, seja favorecida. Já existem várias fontes comerciais de ²-caroteno, mas são raras as fontes de zeaxantina.

The use of microalgae and cyanobacteria as sources of nutrients and bioactive substances for food and dietary supplements has attracted a lot of interest in recent years. Through open column chromatography-visible absorption spectrophotometry, high performance liquid chromatography with a photodiode array detector, thin layer chromatography and functional group chemical reactions, trans- and cis-²-carotene, echinenone, ²-cryptoxanthin, 3-hydroxy-4'-ketocarotenoid, zeaxanthin and 3,3-dihydroxy-4'-ketocarotenoid were identified in the cyanobacterium Synechocystis pevalekii. The cianobacterium was green because of the presence of chlorophylls. When cultivated under stress (80% reduction of nutrient content of the original Conway medium) the chlorophylls disappeared and the cyanobacterium assumed an orange color. ²-Carotene decreased from 307 to 248 µg/g and ²-cryptoxanthin from 94 to 13 µg/g. On the other hand, zeaxanthin increased from 29 to 220 µg/g. Thus, S. pevalekii appears to have commercial potential as source of zeaxanthin, which is implicated in the reduction of the risk of macular degeneration and cataract, together with lutein. The results also showed that conditions for the production of the cyanobacterium can be established so that the biosynthesis of carotenoids important to human health, but difficult to obtain, can be favored. There are already several commercial sources of ²-carotene, but sources of zeaxanthin are rare.