Carmen M. Donangelo

Chlorogenic Acids from Green Coffee Extract are Highly Bioavailable in Humans

Chlorogenic acids (CGA) are cinnamic acid derivatives with biological effects mostly related to their antioxidant and antiinflammatory activities. Caffeoylquinic acids (CQA) and dicaffeoylquinic acids (diCQA) are the main CGA found in nature. Because green coffee is a major source of CGA, it has been used for production of nutraceuticals. However, data on the bioavailability of CGA from green coffee in humans are inexistent. The present study evaluated the pharmacokinetic profile and apparent bioavailability of CGA in plasma and urine of 10 healthy adults for 8 h after the consumption of a decaffeinated green coffee extract containing 170 mg of CGA. Three CQA, 3 diCQA, and caffeic, ferulic, isoferulic, and p-coumaric acids were identified in plasma by HPLC-Diode Array Detector-MS after treatment. Over 30% (33.1 +/- 23.1%) of the ingested cinnamic acid moieties were recovered in plasma, including metabolites, with peak levels from 0.5 to 8 h after treatment. CGA and metabolites identified in urine after treatment were 4-CQA, 5-CQA, and sinapic, p-hydroxybenzoic, gallic, vanillic, dihydrocaffeic, caffeic, ferulic, isoferulic, and p-coumaric acids, totaling 5.5 +/- 10.6% urinary recovery of the ingested cinnamic and quinic acid moiteties. This study shows that the major CGA compounds present in green coffee are highly absorbed and metabolized in humans.

Phenolic compounds in coffee

Phenolic compounds are secondary metabolites generally involved in plant adaptation to environmental stress conditions. Chlorogenic acids (CGA) and related compounds are the main components of the phenolic fraction of green coffee beans, reaching levels up to 14 % (dry matter basis). These compounds have a number of beneficial health properties related to their potent antioxidant activity as well as hepatoprotective, hypoglycemic and antiviral activities. The main groups of CGA found in green coffee beans include caffeoylquinic acids, dicaffeoylquinic acids, feruloylquinic acids, p-coumaroylquinic acids and mixed diesters of caffeic and ferulic acids with quinic acid, each group with at least three isomers. During coffee processing, CGA may be isomerized, hydrolyzed or degraded into low molecular weight compounds. The high temperatures of roasting also produce transformation of part of CGA into quinolactones and, along with other compounds, melanoidins. This review focuses on the chemical characteristics, biosynthesis, and distribution of CGA and related compounds in coffee. The influence of genetic, physiological and environmental factors as well as processing on the chemical composition of coffee beans is discussed. The impact of CGA composition of green coffee on cup quality is also approached. Despite the existence of substantial published information on the total levels of CGA in coffee, more research is needed on the composition of minor phenolic compounds and specific CGA isomers (and related substances) in green and roasted coffee beans, as well as their impact on coffee quality.

Fast simultaneous analysis of caffeine, trigonelline, nicotinic acid and sucrose in coffee by liquid chromatography–mass spectrometry

A rapid liquid chromatography-mass spectrometry method for the simultaneous quantification of caffeine, trigonelline, nicotinic acid and sucrose in coffee was developed and validated. The method involved extraction with hot water, clarification with basic lead acetate and membrane filtration, followed by chromatographic separation using a Spherisorb(®) S5 ODS2, 5μm chromatographic column and gradient elution with 0.3% aqueous formic acid/methanol at a flow rate of 0.2mL/min. The electrospray ionization source was operated in the negative mode to generate sucrose ions and in the positive mode to generate caffeine, trigonelline and nicotinic acid ions. Ionization suppression of all analytes was found due to matrix effect. Calibrations curves prepared in green and roasted coffee extracts were linear with r(2)>0.999. Roasted coffee was spiked and recoveries ranged from 93.0% to 105.1% for caffeine, from 85.2% to 116.2% for trigonelline, from 89.6% to 113.5% for nicotinic acid and from 94.1% to 109.7% for sucrose. Good repeatibilities (RSD<5%) were found for all analytes in the matrix. The limit of detection (LOD), calculated on the basis of signal-to-noise ratios of 3:1, was 11.9, 36.4, 18.5 and 5.0ng/mL for caffeine, trigonelline, nicotinic acid and sucrose, respectively. Analysis of 11 coffee samples (regular or decaffeinated green, ground roasted and instant) gave results in agreement with the literature. The method showed to be suitable for different types of coffee available in the market thus appearing as a fast and reliable alternative method to be used for routine coffee analysis.

Chemical characterization and evaluation of antioxidant properties of Açaí fruits (Euterpe oleraceae Mart.) during ripening

Consumption of açaí fruits has been linked to positive health effects due to its phenolic content and nutritive value. The objective of this study was to characterize açaí fruits chemically and to determine the antioxidant capacity at three different maturity stages. With the exception of fat, amounts of macronutrients, minerals and titratable acids decreased during the ripening process. The same trend was observed for most of the phenolic constituents identified by HPLC-ESI-MS/MS. A consistent decline was shown for flavones and hydroxycinnamic acids. The concentration of the anthocyanins increased in the course of ripening. In accordance with the total amount of the identified phenolic compounds, the antioxidant capacity, measured by TEAC and TOSC, also decreased. However, the contribution of the main phenolic compounds to the overall antioxidant capacity evaluated by TOSC was estimated to be low.

Zinco, estresse oxidativo e atividade física

During intense physical activity there is an increased production of reactive oxygen species that can cause muscle injury and damage to erythrocyte cell membranes, thus impairing athletic performance. In order to prevent the effects caused by oxidative stress, the organism has several antioxidant mechanisms, some of which depending on zinc. The antioxidant properties of this mineral are explained by its role in the regulation of metallothionein synthesis, in the structure of superoxide dismutase, and in the protection of sulfhydryl groups of cell membrane proteins through antagonism with pro-oxidant metals such as iron and copper. Recent studies have shown that the osmotic fragility of erythrocytes is related to the zinc function in cell membranes. Athletes generally have dietary zinc intakes inadequate to compensate for the increased sweat and urine losses to meet and the high biochemical demand. This paper reviews the biological and nutritional significance of zinc in the antioxidant protection during intense physical activity.

Effect of Subadequate Maternal Vitamin-A Status on Placental Transfer of Retinol and Beta-Carotene to the Human Fetus

The placental transfer of retinol and beta-carotene was assessed based on maternal serum, cord serum and placental levels at term parturition in women with adequate (n = 15; serum retinol > 20 micrograms/dl) and subadequate (n = 16; serum retinol < or = 20 micrograms/dl) vitamin-A status. There was no difference in retinol and beta-carotene levels in placenta and cord serum between these groups. However, differences in the relation of maternal, placental and cord blood components were observed between women with adequate and subadequate vitamin-A status. In women with subadequate status, circulating fetal retinol levels correlated with placental retinol levels, and maternal serum beta-carotene correlated with placental retinol. Within this group, maternal serum beta-carotene and cord serum retinol correlated significantly in women with serum retinol levels lower than 15 micrograms/dl. These results suggest that beta-carotene may be a precursor of retinol in placenta and that this conversion may depend on the nutritional status of the mother, being particularly effective in a more depleted state.

Daily supplementation with iron increases lipid peroxidation in young women with low iron stores.

The aim of this study was to determine whether women with low iron stores (plasma ferritin ≤ 20 μg/L) receiving a daily iron supplement for 8 wks at a level commonly used to treat poor iron status develop increased lipid peroxidation as measured by ethane exhalation rates and plasma malondialdehyde. The women served as their own control as pre- and post-supplementation periods were compared. Twelve women participated in the study for a 70-day period and consumed daily iron supplements (98 mg of iron as ferrous sulfate) from day 14 to day 70. Baseline blood and expired air samples were obtained on days 1 and 14; measurements during supplementation were performed on days 56 and 70, that is at 6 and 8 weeks of supplementation. Iron status improved during the iron supplementation period; biochemical indicators of lipid peroxidation also increased. After 6 wks of iron supplementation, serum ferritin almost doubled and body iron more than doubled. Hemoglobin levels increased slightly and other indicators of iron status became normal. However, plasma malondialdehyde (MDA) and breath ethane exhalation rates (BEER) increased by more than 40% between baseline and 6 wks of supplementation; these increases correlated significantly with plasma iron and ferritin levels. MDA was positively correlated with BEER. BEER increased further after 8 wks of iron supplementation. The increased indicators of lipid peroxidation with duration of supplementation and as iron status improved suggest that providing daily nearly 100 mg iron may not be a totally innocuous regimen for correcting iron depletion in women.

Zinc absorption and kinetics during pregnancy and lactation in Brazilian women

BACKGROUND Adjustments in zinc absorption and endogenous excretion maintain zinc homeostasis in nonpregnant adults fed low-zinc diets. The effects on zinc homeostasis of a low zinc intake during pregnancy and lactation have not been described in a longitudinal study. OBJECTIVE We examined longitudinal changes in fractional zinc absorption (FZA) and zinc kinetics in 10 healthy Brazilian women who habitually consumed a marginal zinc diet ( approximately 9 mg Zn/d). DESIGN Zinc status was measured at 10-12 (early pregnancy; EP) and 34-36 (late pregnancy; LP) wk of pregnancy and at 7-8 wk after delivery (early lactation; EL). Zinc kinetics and FZA were studied by using stable isotopic tracers. RESULTS Zinc intake averaged 9 +/- 3 mg/d throughout the study. FZA increased from 29 +/- 6% at EP to 43 +/- 10% at LP and to 39 +/- 13% at EL (P < 0.05). FZA was inversely related to plasma zinc at EL (r = -0.73, P = 0.02) and LP (r = -0.72, P = 0.07). Plasma zinc mass was 23% greater at LP than at EP or EL (P < 0.05). The amount of zinc (mg/d) that fluxed between plasma and the most-rapidly-turning-over extravascular pool was 53% greater at LP than at EP or EL (P < 0.05). The zinc flux between plasma and the less-rapidly-turning-over zinc pool at EL was 27% greater than that at EP or LP, but this difference was not significant. CONCLUSIONS FZA increased significantly in women with marginal zinc intakes during pregnancy and lactation; the increase was higher in women with low plasma zinc. Plasma zinc was distributed into a different exchangeable pool at LP than at EL.

Nutrient composition of banked human milk in Brazil and influence of processing on zinc distribution in milk fractions.

OBJECTIVE AND METHODS We measured the contents of fat, protein, lactose, calcium, phosphorus, zinc, iron, copper, and vitamin A in processed mature milk samples (individual, n = 60, and pooled, n = 10) from a reference human milk bank in Brazil and assessed the effect of pasteurization followed by freezing on the nutrient composition and the pattern of zinc distribution in fractions (fat, whey, and casein) of milk samples (n = 15). RESULTS Mean nutrient concentrations were within expected ranges in mature milk from healthy women, except fat, which was lower. Interindividual variability of nutrient concentrations was high (coefficient of variation, 21-62%) but reduced overall in pooled samples. Processing of milk samples did not affect the nutrient contents but did cause a significant shift (P < 0.04) in the relative distribution of zinc, with a decrease in the whey fraction and an increase in the fat fraction. CONCLUSIONS Redistribution and possible alterations in the zinc-binding pattern during processing in human milk banks may reduce zinc bioavailability to the infant.

Effect of germination of legume seeds on chemical composition and on protein and energy utilization in rats

Abstract 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.