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A fraction C 1 which was very rich in polysaccharides and did not contain sucrose was isolated from high molecular weight water-soluble material obtained from green coffee. After roasting, furfural was identified in fraction C 1 by means of headspace-GC/MS analysis. Roasting of the fraction C 1 clearly affected the arabino-galactan promoting a high loss of arabinose residues. We suggest that furfural found in fraction C 1 originates mainly from arabinogalactan, which, together with sucrose appears to be the major furfural precursor in roasted coffee

The chemical transformations of the volatile fractions of two different Brazilian honeys (cashew and marmeleiro) were monitored during storage under tropical conditions. Five systems, namely: 1 – fresh samples; 2 and 3 – samples heated for 3 and 6 months at 35 – 40 °C; 4 and 5 – samples kept under similar conditions to systems 2 and 3, but containing sodium metabisulphite, were tested. The transformations noted in the volatile fractions of these honeys could be mainly associated to acid or enzymatic hydrolysis of glycosides, volatilization, oxidation or esterification processes. The formation of furan derivatives, linalool derivatives and esters appears to be quite affected by the sodium metabisulphite. The concentrations of most powerful odorants increased during the storage (e.g.: benzenemethanol and isovaleric acid) or remained unchangeable (e.g.: vanillin, furfuryl mercaptan, 2-methoxyphenol).

Brazilian arabica coffee is classified for trading according to the quality of the beverage obtained after roasting and brewing. In the present study, Brazilian green and roasted coffee beans were investigated for possible correlations between cup quality and the levels of sucrose, caffeine, trigonelline and chlorogenic acids, determined by HPLC analysis. Trigonelline and 3,4-dicaffeoylquinic acid levels in green and roasted coffee correlated strongly with high quality. To a lesser extent, caffeine levels were also associated with good quality. On the other hand, the amount of defective beans, the levels of caffeoylquinic acids (predominantly 5-caffeoyilquinic acid), feruloylquinic acids, and their oxidation products were associated with poor cup quality and with the Rio-off-flavor. The fact that similar correlations between cup quality and chemical attributes were observed in green and light roasted samples – the latter used for coffee cup classification – indicates that chemical analysis of green beans may be used as an additional tool for coffee quality evaluation.

The decaffeinated coffee market has been expanding increasingly in the last years. During decaffeination, aroma precursors and bioactive compounds may be extracted. In the present study we evaluate the changes in the chemical composition of C. arabica and C. canephora produced by decaffeination using dichloromethane. A significant change in the chemical composition of both C. arabica and C. canephora species was observed, with differences between species and degrees of roasting. Major changes were observed in sucrose, protein and trigonelline contents after decaffeination. Changes in the levels of total chlorogenic acids and in their isomers distribution were also observed. Lipids and total carbohydrates were not affected as much. The sensory and biological implications of these changes need to be investigated.

The market for decaffeinated coffees has been increasingly expanding over the years. Caffeine extraction may result in losses of other compounds such as chlorogenic acids (CGA) and, consequently, their 1,5-gamma-quinolactones (CGL) in roasted coffee. These phenolic compounds are important for flavor formation as well as the health effects of coffee; therefore, losses due to decaffeination need to be investigated. The present study evaluates the impact of decaffeination processing on CGA and CGL levels of green and roasted arabica coffees. Decaffeination produced a 16% average increase in the levels of total CGA in green coffee (dry matter), along with a 237% increase in CGL direct precursors. Different degrees of roasting showed average increments of 5.5-18% in CGL levels of decaffeinated coffee, compared to regular, a change more consistent with observed levels of total CGA than with those of CGL direct precursors in green samples. On the other hand, CGA levels in roasted coffee were 3-9% lower in decaffeinated coffee compared to regular coffee. Although differences in CGA and CGL contents of regular and decaffeinated roasted coffees appear to be relatively small, they may be enough to affect flavor characteristics as well as the biopharmacological properties of the final beverage, suggesting the need for further study.

Coffee is a product consumed all around the world, Brazil being the biggest exporter. However, little is known about the difference in composition of the different brands in terms of bioactive substances. In the present study, ten of the most consumed brands of coffee in Rio de Janeiro were analyzed. Caffeine contents, trigonelline and total chlorogenic acid varied from 0.8 g/100g to 1.4 g/100g; 0.2 g/100g to 0.5 g/100g and from 3.5 g kg-1 to 15.9 g kg-1, respectively. The large heterogeneity observed in the amounts of the bioactive compounds can be attributed to different formulations of the various brands, as well as to different roasting conditions.

The influence of hydrophobic polypeptides concentrated in beer foam, together with the composition of iso-alpha acids and the content of malto-oligosaccharides in beer on foam stability, has been investigated. The objective was to find out whether a shortage of one of these positive contributors to foam stability could be compensated for by an increased presence of another or whether optimum levels of each contributor is necessary. For that purpose, an image analysis method to evaluate beer foam quality was developed. The foam collapse time was the parameter chosen to group beers according to their foam stability. Profiles of hydrophobic polypeptides that concentrate in beer foam, iso-alpha acids, and malto-oligosaccharides of 14 beer brands were acquired by high-performance liquid chromatography. Principal component analysis (PCA) was performed to show the relationship between beer brands and its composition. Beers that contained propylene glycol alginate as a foam enhancer showed high foam stability except for one beer, which had a low content of hydrophobic polypeptides, thereby highlighting the requirement of threshold levels of hydrophobic polypeptides to obtain stable foam. The data of samples that were devoid of a foam additive were subjected to a discriminant statistical analysis. Foam stability declined in proportion to decreases in hydrophobic polypeptides and to a lesser extent to decreases in iso-alpha-acid contents. Apparently, the content of malto-oligosaccharides were found to have no major influence on foam stability. The model of discriminate analysis was found to explain 100% of the variance in data with 85.2% success in classifying all samples according to the model, suggesting that foam stability is mainly governed by the beer constituents evaluated in this study.

Five isonitrogenous diets formulated to contain 470 g kg(-1) of crude protein, five different levels of crude lipids (190, 210, 230, 250 and 270 g kg(-1)), five different levels of carbohydrates (178, 155, 158, 125 and 110 g kg(-1)) and gross energy (21.2, 21.6, 22.4, 22.8 and 23.2 MJ kg(-1)) were used to investigate the effect of dietary lipid levels on performance and carcass composition of the surubim, Pseudoplatystoma coruscans (Agassiz). Triplicate groups of 11 fish with an average individual body weight of 5.1 +/- 0.2 g were randomly assigned to 15 net cages and fed each test diet twice a day to apparent satiation for 64 days. At the end of the trial there were no significant differences in feed consumption or fish performance. No differences (P > 0.05) were observed in the lipid content of fish carcass and liver. On the contrary, visceral lipid increased (P 0.05) by the dietary lipid and carbohydrate levels. The results of this trial suggest that increasing dietary lipid levels from 190 to 270 g kg(-1) did not improve growth performance or protein sparing and caused an undesirable increase in the visceral lipid content of surubim fingerlings.

Of all plant constituents, coffee has one of the highest concentrations of chlorogenic acids. When roasting coffee, some of these are transformed into chlorogenic acid lactones (CGL). We have studied the formation of CGL during the roasting of coffee beans in Coffea arabica cv. Bourbon; C. arabicacv. Longberry; and C. canephora cv. Robusta. Individual CGL levels were determined by comparison of HPLC peaks with those of synthetic CGL standards. Seven CGL were identified: 3-caffeoylquinic-1,5-lactone (3-CQL), 4- caffeoylquinic-1,5-lactone (4-CQL), 3-coumaroylquinic-1,5-lactone (3-pCoQL), 4-coumaroylquinic-1,5-lactone (4-pCoQL), 3-feruloylquinic-1,5-lactone (3-FQL), 4-feruloylquinic-1,5-lactone (4-FQL), and 3,4-dicaffeoylquinic-1,5-lactone (3,4-diCQL). 3-CQL was the most abundant lactone in C. arabica and C. canephora, reaching peak values of 230 +/- 9 and 254 +/- 4 mg/100 g (dry weight), respectively, at light medium roast ( approximately 14% weight loss). 4-CQL was the second most abundant lactone (116 +/- 3 and 139 +/- 2 mg/100 g, respectively. The maximum amount of CGL represents approximately 30% of the available precursors. The relative levels of 3-CQL and 4-CQL in roasted coffee were reverse to those of their precursors in green coffee. This suggests that roasting causes isomerization of chlorogenic acids prior to the formation of lactones and that the levels of lactones in roasted coffee do not reflect the levels of precursors in green coffee.

A group of 10 morphological mutants of Aspergillus niger was tested for synthesis of phytase. Strain 11T25A5 was selected for phytase production in solid state fermentation (SSF) in the presence of phytic acid (PA). The production of phytase in the medium was accompanied by degradation of phytic acid. Phytase activity increased from 28 to 72% when lupin flour was used in the fermentation mixture. The residual content of phytic acid in the fermented material depends on both the proportion of lupin flour in the mixture and the particle size of the flour. Coarse lupin flour produced fermented material with a lower level of residual phytic acid. The fermentation of lupin flour with A. niger strain 11T2545 may be used to obtain a low phytate biomass with potential for use as an ingredient for feed or food production.

The iron-reducing activity of coffee beverages was determined by the ferric reducing antioxidant power (FRAP) assay. The influence on FRAP due to the degree of roasting (light, medium, and dark), species (Coffea arabica and Coffea robusta), and caffeine content (regular and decaffeinated) was investigated using ground and soluble coffee samples. The concentration of specific chlorogenic acids and caffeine in the beverages was determined by high-performance liquid chromatography and related to FRAP using Pearson correlation coefficients. All measurements were expressed per unit of soluble solids. Beverages prepared with ground coffee had, on average, 27% higher FRAP values than those prepared with soluble coffee (p0.05). In the former beverages, FRAP of C. robusta samples was significantly higher (on average, 50.3%) when compared to that of C. arabica samples, and FRAP values decreased with increasing degree of roasting (p0.05). A strong correlation (r0.91) was found between FRAP and the total content of chlorogenic acids, particularly that of the caffeoylquinic acid isomers. The iron-reducing activity of coffee beverages was not influenced by caffeine.

The effect of preharvest soil application of potassium on the development of the physiological disorder called internal browning (IB) in harvested pineapple fruit was studied. Potassium was applied as a soil dressing at 4–20 g of K 2O per plant in three split applications at 8, 24 and 40 weeks after planting. Fruit were harvested 19 months after planting and were harvested at two maturity stages, classified as color break (CB) or half ripe (HR) and stored at 7 ◦ C and 95% RH for 15 days followed by 5 days at 25 ◦ C to simulate commercial handling. IB was more severe in HR than in CB fruit. Application of potassium reduced IB in fruit of both maturities. Maximum response was achieved with 16 g of K2O per plant. Phenolic content of CB and HR fruit from plants treated with potassium was reduced up to 38 and 39%, respectively. Polyphenoloxidase (PPO) and phenylalanine ammonia-lyase (PAL) activities varied according to the stage of maturity with higher activities in the ripe fruit. Potassium treatment promoted a progressive and more accentuated decrease of PPO activities in HR when compared to CB fruit. Similarly, PAL and POD activities were lower in fruit from plants treated with potassium as was the incidence of IB. This work showed that soil applications of potassium to growing pineapple plants could improve fruit quality. © 2004 Elsevier B.V. All rights reserved.

Anthocyanin aglycons and other phenolic compounds were identified in acerola (Malpighia punicifolia, L.). Anthocyanins, flavonoids and phenolic acids were fractionated and characterized by means of chromatographic and spectral data. The total content of anthocyanin pigments was 37.5 mg per 100 g of ripe acerola skin. The phenolic pigments identified were pelargonidin, malvidin 3,5-diglycoside and cyanidin 3-glycoside. Quercetin, kaempferol and the phenolic acids p-coumaric acid, ferulic, caffeic and chlorogenic were also identified.

Hepatic stellate cells (HSCs) are the major site of retinol (ROH) metabolism and storage. GRX is a permanent murine myofibroblastic cell line, derived from HSCs, which can be induced to display the fat-storing phenotype by treatment with retinoids. Little is known about hepatic or serum homeostasis of beta-carotene and retinoic acid (RA), although the direct biogenesis of RA from beta-carotene has been described in enterocytes. The aim of this study was to identify the uptake, metabolism, storage, and release of beta-carotene in HSCs. GRX cells were plated in 25 cm(2) tissue culture flasks, treated during 10 days with 3 micromol/L beta-carotene and subsequently transferred into the standard culture medium. beta-Carotene induced a full cell conversion into the fat-storing phenotype after 10 days. The total cell extracts, cell fractions, and culture medium were analyzed by reverse phase high-performance liquid chromatography for beta-carotene and retinoids. Cells accumulated 27.48 +/- 6.5 pmol/L beta-carotene/10(6) cells, but could not convert it to ROH nor produced retinyl esters (RE). beta-Carotene was directly converted to RA, which was found in total cell extracts and in the nuclear fraction (10.15 +/- 1.23 pmol/L/10(6) cells), promoting the phenotype conversion. After 24-h chase, cells contained 20.15 +/- 1.12 pmol/L beta-carotene/10(6) cells and steadily released beta-carotene into the medium (6.69 +/- 1.75 pmol/ml). We conclude that HSC are the site of the liver beta-carotene storage and release, which can be used for RA production as well as for maintenance of the homeostasis of circulating carotenoids in periods of low dietary uptake.

Nove amostras de café solúvel representativas das marcas brasileiras foram adquiridas no mercado e analisadas quanto a composição de ácidos clorogênicos, cafeína e trigonelina, através de cromatografia líquida de alta eficiência. Os isômeros dos principais grupos de ácidos clorogênicos (ACG), ou seja, ácidos cafeoilquínicos (ACQ), dicafeoilquínicos (ADICQ) e feruloilquínicos (AFQ) foram determinados. O grupo de ACQ foi predominante em todas as amostras sendo o 5-ACQ o maior componente nas amostras. Os teores totais de ACG variaram de 0,6 a 5,9g%. As amostras com baixo teor de ACG foram provavelmente aquelas obtidas de grãos submetidos a torrefação intensa. Os teores de trigonelina foram também bastante variáveis situando-se na faixa de 0,3 a 1,0g% refletindo as diferentes condições de processamento utilizadas pelos fabricantes. Com exceção das amostras descafeinadas que apresentaram resíduo de 0,065g% os teores de cafeína situaram-se em torno de 2,7g%. A menor variabilidade nos teores de cafeína deve-se a sua alta estabilidade térmica. O conhecimento da composição do café solúvel, principalmente em relação aos compostos bioativos é relevante para o direcionamento de futuros estudos e para a avaliação da contribuição do café nos efeitos biológicos específicos da dieta. Nine Brazilian instant coffee samples were analysed for chlorogenic acids, caffeine and trigonelline using HPLC. Different isomers of chlorogenic acid (CGA) in the groups of caffeoylquinic acids (CQA), dicaffeoylquinic acids (DICQA) and feruloylquinic acids (FQA) were determined. The isomers of the CQA group were predominant in all samples with 5-CQA being the most abundant. Total CGA levels varied from 0.6 to 5.9g%. The samples with lowest CGA content were probably the ones obtained from dark roasted coffee beans. The trigonelline levels varied between 0.3 to 1.0g% reflecting the different conditions used by the manufacturers. The decaffeinated coffee retained about 0.065g% of caffeine and the majority of the other samples showed levels around 2.7g%. The small variability of caffeine within the samples was due to its resistance to the heat treatment. The knowledge of instant coffee composition is relevant to evaluate the real contribution of coffee to the biological effects of the diet.

Methods for characterization of hop varieties include analyses of bitter acids and essential oils, followed by comparison of the chemical composition, particularly chromatographic profiles. In the present work discrimination of different hop varieties was carried out based on their essential oil volatile composition, assessed by headspace gas chromatography, with subsequent statistical treatment of the data. Differences and similarities were determined in samples from USA, New Zealand and Europe, using correlation and cluster analysis. Aroma hops presented low levels of myrcene while bitter samples showed high levels of beta-caryophyllene, aloaromadendrene and also the sum of the marker ratios, independently of being in the form of pellets or extracts. Highly correlated samples with no significant differences have good possibility to substitute each other in the beer manufacture. Os métodos utilizados para caracterização do lúpulo envolvem a análise de substâncias amargas e do óleo essencial, seguida da comparação da composição química e perfis cromatográficos. No presente trabalho, diferentes variedades e produtos de lúpulo foram discriminados através da análise da composição dos óleos essenciais por cromatografia a gás no modo headspace em fase gasosa, com subsequente tratamento estatístico. Diferenças e similaridades foram determinadas em amostras provenientes dos Estados Unidos, da Nova Zelândia e da Europa, usando-se análise de correlações e "cluster". Os lúpulos com características de aroma apresentaram baixos níveis de mirceno, enquanto aqueles com características de amargor apresentaram altos teores de beta-cariofileno e aloaromadendreno bem como as somas das razões dos marcadores escolhidos, independentemente de estarem sob a forma de "pellets" ou de extratos. Amostras altamente correlacionadas entre si e sem diferenças estatísticas mostram boa possibilidade para substituições entre elas, na produção da cerveja.

Caffeine consumption increases the urinary excretion of calcium and other minerals. Factors that affect caffeine metabolism such as steroid hormones may modify this effect. The purpose of this study was to evaluate the influence of oral contraceptive (OC) use on the 4-h urinary excretion of calcium, phosphorus, magnesium, zinc, sodium, potassium and caffeine metabolites in response to a high caffeine dose given as coffee beverage. Adult women, 20-29 y, users (+OC, n = 15) and nonusers (-OC, n = 15) of oral contraceptives, with calcium intake approximately 500 mg/d, participated in two tests, caffeine load (5 mg/kg body weight) and no-caffeine control, in a randomized crossover design. The net increase (caffeine load corrected by no caffeine) in urinary excretion of most minerals was significantly higher in -OC than in +OC (P < 0.05), with the larger group difference for calcium (ninefold) followed by magnesium (twofold), zinc (onefold) and potassium (onefold). Net increases in urinary excretion of 1-methylurate and paraxanthine were about three- and fivefold higher, respectively, in -OC than in +OC (P < 0.05) whereas net increases in urinary excretion of 5-acetylamino-6-formylamino-3-methyluracil (AFMU) and 1,7-dimethylurate were over twofold higher in the +OC than in -OC (P < 0.05). Following the caffeine load, most urinary minerals showed negative correlation with urinary 1-methylurate in -OC (R

An accurate method for identification of fatty acids in complex mixtures analyzed by temperature-programmed capillary gas chromatography is described. The method is based on a mathematical approach using regression curves obtained by plotting the relative retention times of fatty acid methyl esters (FAMEs) analyzed in isothermal and gradient temperature conditions. The method was applied to a complex biological sample (human milk), and it was possible to identify 64 fatty acids, including branched-chain and other fatty acids for which reference standards were not readily available. The identities of the majority of the peaks were confirmed by mass spectrometry. The relative residuals and the relative differences between estimated and measured relative retention times of individual FAMEs varied from 0.03 to 3.15% and from 0.0 to 2.9%, respectively. The method is useful for identification of fatty acids in routine analysis.

Four isonitrogenous (46% crude protein) and isolipidic (18.5%) diets were formulated using four different lipid sources: lard (diet 1); corn oil (diet 2); soybean oil (diet 3); and linseed oil (diet 4) to evaluate the performance and body composition of surubim . Ten fingerlings (mean weight, 2.75±0.2 g) were randomly assigned to net cages (60-l capacity). Triplicate groups were fed each test diet twice a day to apparent satiation for 63 days. No difference (P>0.05) was observed for feeding performance. On the other hand, fatty acid composition of carcass lipids was affected (P

Four diets were formulated to contain a constant protein level (46%) and four different lipid levels (6%, 10%, 14% and 18%). The diets were fed to surubim, a Brazilian native carnivorous freshwater fish. Gross energy of the diets were 4440, 4650, 4840, and 5140 (kcal/kg). Surubim fingerlings (average weight: 2.72 g/fish) were randomly assigned to treatments and fed the test diets twice a day to apparent satiation for 62 days. The study was conducted in triplicate with 13 fish distributed in 60-l net-cages set up in 1000-l plastic tanks (three cages per tank), equipped with a flow through freshwater system and water temperature of 27±1 °C. The diet with 6% lipid gave the poorest performance, while fish fed the highest lipid level showed the best nutritional performance. Feed conversion ratio and daily feed consumption showed a marked decrease ( P P P

This work investigates the content of feruloylquinic (FQA), caffeoylquinic (CQA) and dicaffeoylquinic (diCQA) acids in the peel, pulp and seed of 22 tropical fruits from Brazil. 3-CQA, 4,5-diCQA and 4- and 5-FQA were not detected in any of the fruits analysed. Relatively small amounts of 4-CQA (4.0–48.7 mg kg−1) were found in the peel and/or pulp of seven of the fruits; only the peel of Artocarpus heterophyllus was significantly (p

Cellular phospholipids of Sertoli cells from immature rats were labeled with [14C]-choline. Two sphingomyelin bands (SM1 and SM2) were identified by TLC. The incorporation of [14C]-choline over a 45 h period of incubation demonstrated that there are differences in labeling kinetics between SM1 and SM2. The subcellular location of SM1 and SM2 was investigated by accessibility to bacterial sphingomyelinase. The results showed the existence of two SM pools in Sertoli cells, but an equal cellular distribution of SM1 and SM2. SM2 is characterized by a relatively high content of unsaturated fatty acids. The inhibition of vesicular flow by monensin determines a decrease of about 60–70% in incorporation into SM1 and SM2, suggesting the existence of at least two sites of sphingomyelin synthesis. Pulse-chase and time-course experiments indicated a phosphatidylcholine → SM precursor product relationship and differences in kinetic properties between SM1 and SM2. Resynthesis experiments showed that monensin had only a partial inhibitory effect on SM1 resynthesis, and a second sphingomyelinase treatment demonstrated that the resynthesized fraction reached the outer leaflet of the plasma membrane. The 60–70% inhibition of SM synthesis by monensin showed that the trans-Golgi cisternae and the trans-Golgi network are the most likely sites of bulk SM synthesis, and that about 15% of SM was synthesized in the cis/medial Golgi apparatus. Additionally the results indicated that plasma membrane SM synthase activity could be the site of about 15% of SM synthesis in Sertoli cells.

The effect of stage of maturity on the chemical composition and volatile components of acerola (Malpighia punicifolia L.) was investigated in three different stages. Stage of maturation was characterized by different indicators such as color, vitamin C, soluble solids, protein, ash, moisture, titrable acidity, pH and sugars. Titrable acidity, sugars and soluble solids increased and vitamin C and protein decreased with the progress of maturation. The volatile fraction was analysed by GC–MS. It was possible to identify 31 compounds in the mature (red) fruits, such as acethyl-methyl-carbinol, 2-methyl-propyl-acetate, limonene, E-Z-octenal, ethyl hexanoate, isoprenyl butirate and acetofenone; 23 in the intermediate (yellow), such as, methyl hexanoate, 3-octen-1-ol and hexyl butirate; and 14 in the immature (green) fruit, such as methyl-propyl-ketone, E-Z-hexenyl-acetate and 1-octadecanol.

The levels of 10 oligosaccharides in 70 genuine Brazilian honeys of different floral types are reported. The contents of sucrose and isomaltose were broad, ranging from mean values of 0.07–0.77 and 0.18–0.71%, respectively. The mean values for maltose were in the range 1.58 to 3.77%. The level of turanose (0.78–2.03%) was similar to that of nigerose (1.11–2.81%). Low amounts of melibiose (0.05–0.15%) and panose (0.03–0.08%) were found in Brazilian honeys. Maltotriose, melezitose and raffinose, were present with mean values of 0.24–1.03, 0.21–0.37 and 0.10–0.25%, respectively. Between Brazilian states, honeys from Sao Paulo had mean values for melibiose significantly (P

The effect of heat treatment of germinated soybean, lupin, and black bean on chemical composition and protein utilization in rats was evaluated. Heat treatment caused complete inactivation of trypsin inhibitors whereas it did not affect phytic acid levels. Proximate components, minerals, and amino acids did not change, but low molecular weight sugars were affected by heat treatment differently for each germinated legume. The sugar digestibility ratio (total digestible sugars/total nondigestible sugars) in germinated black beans doubled after heat treatment. True protein digestibility (TD) increased with heat treatment only in germinated soybean. Net protein utilization was markedly improved (20%) with heat treatment in germinated soybean and lupin. Utilizable protein of heat-treated germinated legumes was 289, 236, and 132 g/kg of legume dry weight for soybean, lupin, and black bean, respectively. Supplementation with methionine did not alter TD but improved all other indices of protein utilization in the germinated legumes, particularly in black bean. All three germinated legumes become equivalent in protein quality when heating and supplementation with methionine are combined with germination. The use of germinated heat-treated soybean, lupin, and black bean on their own and/or as food ingredients is nutritionally advantageous due to the low content of nondigestible oligosaccharides and the high protein utilization.

The levels of water, HMF, free proline, total acidity, diastase activity, fructose and glucose in 74 different floral type honeys from four Brazilian regions are reported. The majority of the samples showed adequate water and HMF contents indicating the use of good practices by beekeepers in Brazil. Large variation in the contents of proline (389–520 mg/kg) was found in the honeys from the four regions studied. These findings are presumably due to the more intensive labor of the bees on the collected nectar by adding gland secretions. The high amount of diastase (40–120°G) found in some honeys from the northeast region could be due to the visit of the bees to Manhiot sp. (cassava) flour factories to collect starch-rich food, consequently increasing the diastase activity in the honey. Xerotolerant yeasts may be responsible for higher total acidity and ratios below 1 for fructose/glucose found in some samples. The majority of the analysed honeys (82%) were within the limits of the European Codex Honey Standards and Brazilian legal regulations.

Rollinia mucosa produces furofuranic lignans (magnolin, epiyangambin, yangambin) that are antagonists of platelet-activating factor (PAF). The biosynthetic capacity and the potential for the accumulation of furofuranic lignans, including epieudesmin, of the plants cultured both in vivo and in vitro conditions were evaluated. The production and the pattern of lignans accumulated were dependent on the origin of the plant material and the plant organ. The major accumulation of lignans was observed in leaves. In the mature leaves of in vivo grown seedlings magnolin and yangambin predominated, in contrast to leaves from in vitro propagated plants that presented epiyangambin as the major lignan.

Liver is a major site of retinoid metabolism and storage, and more than 80% of the liver retinoids are stored in hepatic stellate cells. These cells represent less than 1% of the total liver protein, reaching a very high relative intracellular retinoid concentration. The plasma level of retinol is maintained close to 2 microM, and hepatic stellate cells have to be able both to uptake or to release retinol depending upon the extracellular retinol status. In view of their paucity in the liver tissue, stellate cells have been studied in primary cultures, in which they loose rapidly the stored lipids and retinol, and convert spontaneously into the activated myofibroblast phenotype, turning a long-term study of their retinol metabolism impossible. We have analyzed the retinol metabolism in the established GRX cell line, representative of stellate cells. We showed that this cell line behaves very similarly, with respect the retinol uptake and release, to primary cultures of hepatic stellate cells. Moreover, we showed that the cellular retinol binding protein (CRBP-I) expression in these cells, relevant for both uptake and esterification of retinol, responds to the extracellular retinol status, and is correlated to the retinol binding capacity of the cytosol. Its expression is not associated with the overall induction of the lipocyte phenotype by other agents. We conclude that the GRX cell line represents an in vitro model of hepatic stellate cells, and responds very efficiently to wide variations of the extracellular retinol status by autonomous controls of its uptake, storage or release.

The antioxidant activity of 5-caffeoylquinic acid on soybean oil in the presence of phytic acid at concentration ranges of 50–400 mg/kg oil or citric acid at 200 mg/kg oil was investigated. The oil was stored at 55 °C for 6 d and monitored by peroxide and conjugated diene measurements. Both citric and phytic acids do not appear to provide any synergistic effects with 5-caffeoylquinic acid. The results showed that 5-caffeoylquinic acid may act both as primary antioxidant and metal chelator.

Trehalose is a disaccharide widely distributed in nature with great potential for application in different fields. Determination of trehalose has been carried out for many years using the anthrone colorimetric method, which may be subject to interferents. Alternatives to this problem seem to be the use of HPLC techniques or specific enzymatic assays. In the present work, a simple normal-HPLC procedure was applied to the analysis of different yeast extract samples and the results compared either to the conventional anthrone method or by an enzymatic assay based on the cleavage of trehalose by trehalase. Each method showed correlations over 0.97 with the others; however, only HPLC and the enzymatic method were statistically identical (p

The antioxidant activity of 5-caffeoylquinic acid (5CQA) at concentration ranges of 0.01–0.08% (w/w) was compared with 0.02% (w/w) butylated hydroxytoluene (BHT) in soybean oil. The oil was stored in air at 55 °C and monitored by peroxide and conjugated diene measurements. Both 0.01% and 0.02% 5-CQA showed lower peroxide values than BHT only on the first day. However, on days 1, 2, 3 and 4, 0.04% 5-CQA reduced the peroxide value to 68%, 47%, 45% and 90% of that observed with BHT. Use of 5-CQA appears to delay the formation of peroxides and up to 0.04% (w / w) its antioxidative action increases with concentration for up to 3 days.

Flavour precursors from water-soluble green coffee low molecular weight (B) and high molecular weight (C) fractions were investigated and the volatiles formed during roasting were identified by high resolution gas chromatography/mass spectrometry (HRGC/MS). Roasting promoted extensive degradation of trigonelline, sucrose and amino acids in fraction (B) and of arabinogalactan in fraction (C). The analyses of the roasted isolated fractions showed that furans are not only formed by sucrose degradation but also by arabinogalactan pyrolysis. Also, pyrazines appear to be mainly formed by pyrolysis of hydroxy amino acids from fraction (C). The results also showed that pyridine found in roasted coffee is not exclusively formed by trigonelline degradation but also by protein pyrolysis.

Chemical composition of soybeans, lupin seeds and black beans, and protein utilization and energy digestibility of soybeans and lupin seeds determined in a rat model, were compared before and after a 48-h germination. Black beans had a much higher starch content and lower levels of low-molecular-weight (LMW) sugars than soybeans and lupin seeds. Lupin seeds had about twice as much non-starch polysaccharides than the other legumes and higher insoluble dietary fiber. Soluble dietary fiber represented over one third of total dietary fiber in all legumes. After germination, LMW α-galactosides decreased in all seeds, particularly in lupins. Sucrose levels increased in lupins and black beans but decreased in soybeans. Biological indices were significantly higher in lupin seeds than in soybeans. Germination produced a small increase in protein utilization in both legumes. These results indicate that the main advantage of a 48-h germination of legume seeds is the reduction in the α-galactosides.

A sequential fractionation method to isolate water-soluble fractions of green Arabica coffee is described. Low- and high-molecular-weight fractions were obtained by treating the dried water extract with aqueous ethanol (80%, v/v). High-performance gel filtration chromatography was used to show some differences in molecular weight distribution between fractions. Flavour precursors were detected in both fractions. Arabinogalactan was the main polysaccharide found in the water-soluble high-molecular-weight fraction, together with large amounts of protein. Important flavour precursors such as sucrose, trigonelline and chlorogenic acid were detected in the low-molecular-weight fraction. A simple and rapid headspace method was developed to obtain the volatile profiles produced by the roasted fractions. Volatiles were immediately collected after roasting in a sealed tube and submitted to gas chromatography. The chromatographic profiles obtained showed considerable differences between fractions and revealed an important contribution to aroma formation.

Subjects submitted to untreated and processed test meals of Lupinus albus and Lupinus angustifolius had decreases in breath-hydrogen concentrations (as maximum and cumulative changes), for processed samples compared to untreated samples. Maximum changes (means) in breath-hydrogen decreased from 56.7 and 66.7 Δppm in untreated L. albus and L- angustifolius, respectively, to 8.4. and 5.9 Δppm in debittered samples (p

Seeds of wild lupin species and several cultivars were analyzed for phytate, calcium, zinc, iron, copper and manganese composition. Mineral content showed high variability within varieties, particularly Mn, with 61–327 mg/100 g dry matter for L. albus and 1·5–38 mg/100 g dry matter between other species. The ranges (mg/100 g dry matter) of other minerals were: Ca, 134–350; Fe, 2·4–10·8; Zn, 2·9–17·6; Cu, 0·4–1·4. Phytate varied from 0·4 to 1·2 g/100 g dry matter with cultivars of L. albus and L. cosentinii presenting the lowest values. Very low phytate: Zn and (phytate × Ca) : Zn molar ratios were observed in wild L. digitatus (4·4 and 0·3) and L. pilosis P23030 (5·3 and 0·3), indicating excellent Zn bioavailability. Phytate : Ca molar ratios of all samples indicate similar or better bioavailability of Ca as compared to other legume seeds.

About 20% of Brazilian raw coffee production is considered inappropriate for exportation. Consequently, these beans are incorporated to good quality beans in the Brazilian market. This by-product of coffee industry is called PVA due to the presence of black (P), green (V) and sour (A) defective beans which are known to contribute considerably for cup quality decrease. Data on the volatile composition of Brazilian defective coffee beans are scarce. In this study, we evaluated the volatile composition of immature, black-immature, black defective beans and PVA compared to good quality beans. Potential defective beans markers were identified.

Connective tissue cells of liver parenchyma are known as hepatic myofibroblasts and lipocytes (fat-storing cells, Ito-cells). They are considered to belong to a single cell lineage, that may switch between these two phenotypes. We have studied cellular and molecular parameters and controls of this switch in the murine GRX cell line, established from liver fibro-granulomatous lesions induced by schistosomal infection. Accumulation of neutral lipids (triacylglycerols, monoalkyl-diacylglycerol, cholesterol) was monitored. It was dependent upon induction with indomethacin. Insulin alone did not induce lipid accumulation in GRX cells, but in cells induced by indomethacin it increased the quantity of stored lipids. We propose that hepatic lipocytes are not cells directly involved in energy storage, but that they represent a particular cell population specialized in storage and in controls of the homoeostasis of lipid-soluble substances at the systemic level.

A method based on high performance gel filtration chromatography, using a TSK 3000-SW column, was developed for the simultaneous determination of total chlorogenic acid and caffeine in coffee samples. The method presented good linearities and recoveries for both compounds. Comparison with results obtained by reversed phase chromatography for caffeine and by the AOAC procedure and an adapted reversed phase chromatographic method for chlorogenic acid showed good correlations between the proposed method and the reversed phase procedures (0·997 for caffeine and 0·998 for chlorogenic acid). The AOAC results for chlorogenic acid showed systematically higher values than the proposed method. The proposed method gave a CV(%) of 6·5 for caffeine and 5·0 for chlorogenic acid and is adequate when applied to the analysis of different samples of green, roasted decaffeinated and instant coffees.

Ten varieties of P. vulgaris were analyzed for their oligosaccharide composition and trypsin inhibitor activity. One of these varieties was studied further to verify the effect of cooking time and germination on trypsin inhibitor activity and oligosaccharide contents. This sample was also submitted to a group of volunteers to compare untreated and three days-germinated beans as to their flatulence capacity, by measuring H 2 production in the expired air. Cooking for 60 min was sufficient to inactivate over 90% of trypsin inhibitors but promoted only about 15% of α-galactoside loss. Germination promoted a progressive decrease of α-galactosides with 77% loss after the third day. Germination for 3 days proved to be efficient to reduce flatulence with all volunteers showing no H 2 responses above the cut off level. Cooking and germination may be useful procedures to inactivate trypsin inhibitors and also to decrease flatulence in legumes.

The present work studies the effect of the boiling on the 5-caffeoylquinic acid (5-CQA) content of potatoes and carrots and investigates the susceptibility of the 5-CQA to a oven heating at 40, 100, or 220°C for 5, 15, 30, 45 or 60 min. A significant reduction (p

An HPLC method with an evaporative light scattering detector was optimized and validated for quantification of carbohydrates in beer. The chromatographic separation was achieved using a Spherisorb NH2, 5 microm chromatographic column and gradient elution with acetonitrile/water. The determinations were performed in the linear range of 0.05-5.0 g/L for fructose, 0.05-5.0 g/L for glucose, 0.05-15.0 g/L for maltose, 0.05-10.0 g/L for maltotriose, and 0.05-5.0 g/L for maltotetraose. The detection limits were 0.005 g/L for fructose, 0.008 g/L for glucose, and 0.01 g/L for maltose, maltotriose, and maltotetraose. The reliability of the method in terms of precision and accuracy was evaluated in three beer matrices, low alcohol beer, 6% alcohol beer, and beer made with part of adjuncts (4.5% alcohol). Relative standard deviations (RSDs) ranged between 1.59 and 5.95% (n = 10), and recoveries ranged between 94 and 98.4%.

A method is proposed for the simultaneous determination of total chlorogenic acid (CGA), trigonelline and caffeine in green coffee using high performance gel filtration chromatography. The method presents good linearities (0.9996, 0.9999 and 0.9998) and recoveries (97%, 96% and 96%) with high correlations (0.9158, 0.9715 and 0.9445) for the CGA, trigonelline and caffeine, respectively when compared to reverse phase HPLC techniques. The proposed method appears to be an adequate method for quality control in the coffee industry.

The composition of digestible sugars (ds) and non-digestible sugars (nds) was determined in 20 soya bean cultivars grown in Brazil. In addition, a comparison of three different extraction procedures for sugar analysis by HPLC is presented. Total α-galactosides in the samples were in the range 3.9–5.3 g% while fructose + sucrose varied from 4.0 to 6.1 g% dry basis. Based on the analysis of protein and oil data together with total galactosides, stachyose and ds nds ratios, one variety (IAS-4) appears to be more appropriate for selection.

Retinol is stored in liver, and the dynamic balance between its accumulation and mobilization is regulated by hepatic stellate cells (HSC). Representing less than 1% total liver protein, HSC can reach a very high intracellular retinoid (vitamin-A and its metabolites) concentration, which elicits their conversion from the myofibroblast to the fat-storing lipocyte phenotype. Circulating retinol is associated with plasma retinol-binding protein (RBP) or bovine serum albumin (BSA). Here we have used the in vitro model of GRX cells to compare incorporation and metabolism of BSA versus RBP associated [(3)H]retinol in HSC. We have found that lipocytes, but not myofibroblasts, expressed a high-affinity membrane receptor for RBP-retinol complex (KD = 4.93 nM), and both cell types expressed a low-affinity one (KD = 234 nM). The RBP-retinol complex, but not the BSA-delivered retinol, could be dislodged from membranes by treatments that specifically disturb protein-protein interactions (high RBP concentrations). Under both conditions, treatments that disturb the membrane lipid layer (detergent, cyclodextrin) released the membrane-bound retinol. RBP-delivered retinol was found in cytosol, microsomal fraction and, as retinyl esters, in lipid droplets, while albumin-delivered retinol was mainly associated with membranes. Disturbing the clathrin-mediated endocytosis did not interfere with retinol uptake. Retinol derived from the holo-RBP complex was differentially incorporated in lipocytes and preferentially reached esterification sites close to lipid droplets through a specific intracellular traffic route. This direct influx pathway facilitates the retinol uptake into HSC against the concentration gradients, and possibly protects cell membranes from undesirable and potentially noxious high retinol concentrations.

Sphingolipids play a relevant role in cell-cell interaction, communication, and migration. We studied the sphingolipid content in the murine hepatic stellate cell line GRX, which expresses the myofibroblast phenotype, and can be induced in vitro to display the fat-storing phenotype. Lipid modifications along this induction were investigated by labeling sphingolipids with [(14)C]galactose, [(14)C]serine, or [(14)C]choline, and determination of fatty acid composition of sphingomyelin. The total ganglioside content and the GM2 synthase activity were lower in myofibroblasts. Both phenotypes presented similar gangliosides of the a-pathway: GM2, GM1, and GD1a as well as their precursor GM3. Sphingomyelin and all the gangliosides were expressed as doublets; the upper/lower band ratio increased in lipocytes, containing more long-chain fatty acids in retinol-induced lipocytes as compared to the insulin/indomethacin induced ones. Time-course experiments indicated a transfer of metabolic precursors from phosphatidylcholine to sphingomyelin in the two phenotypes. Taken together, these results indicate that myofibroblast and lipocytes can use distinct ceramide pools for sphingolipid synthesis. Differential ganglioside expression and presence of the long-chain saturated fatty acids suggested that they may participate in formation of distinct membrane microdomains or rafts with specific functions on the two phenotypes of GRX-cells.

We have examined retinol esterification in the established GRX cell line, representative of hepatic stellate cells, and in primary cultures of ex vivo purified murine hepatic stellate cells. The metabolism of [3H]retinol was compared in cells expressing the myofibroblast or the lipocyte phenotype, under the physiological retinol concentrations. Retinyl esters were the major metabolites, whose production was dependent upon both acyl-CoA:retinol acyltransferase (ARAT) and lecithin:retinol acyltransferase (LRAT). Lipocytes had a significantly higher esterification capacity than myofibroblasts. In order to distinguish the intrinsic enzyme activity from modulation of retinol uptake and CRBP-retinol content of the cytosol in the studied cells, we monitored enzyme kinetics in the purified microsomal fraction. We found that both LRAT and ARAT activities were induced during the conversion of myofibroblasts to lipocytes. LRAT induction was dependent upon retinoic acid, while that of ARAT was dependent upon the overall induction of the fat storing phenotype. The fatty acid composition of retinyl-esters suggested a preferential inclusion of exogenous fatty acids into retinyl esters. We conclude that both LRAT and ARAT participate in retinol esterification in hepatic stellate cells: LRAT's activity correlates with the vitamin A status, while ARAT depends upon the availability of fatty acyl-CoA and the overall lipid metabolism in hepatic stellate cells.