Biochelates from Spent Coffee Grounds Increases Iron Levels in Dutch Cucumbers but Affects Their Antioxidant Capacity

Spent coffee grounds (SCG) are a type of food waste and are produced in abundance around the world. However, their utilization as a soil organic amendment is challenging due to their phytotoxic effect. In the present work, the impact of agronomic biofortification on Dutch cucumbers was investigated using different chemically modified SCG and analyzing their effects on iron contents, their capacity for releasing antioxidants, and the production of short-chain fatty acids after in vitro digestion-fermentation. The results indicated variations in the iron contents and chemical compositions of cucumbers according to the treatment groups. Functionalized and activated hydrochar from SCG increased Fe levels in cucumbers. Although activated hydrochar obtained at 160 °C and functionalized with Fe showed the highest iron supply per serving, differences in antioxidant capacity and short-chain fatty acid production were observed between the groups. It is concluded that growing conditions and the presence of iron may significantly influence the contribution of these cucumbers to the dietary intake of nutrients and antioxidants, which could have important implications for human health and nutrition.

Zn Biofortification of Dutch Cucumbers with Chemically Modified Spent Coffee Grounds: Zn Enrichment and Nutritional Implications

Spent coffee grounds (SCGs) are a food waste with a large generation around the world. However, their utilization as a soil organic amendment is difficult due to their phytotoxic effect. In the present work, the impact of agronomic biofortification on Dutch cucumbers was studied by using different chemically modified SCGs, analyzing their effects on Zn content, the release of antioxidant capacity and the production of short-chain fatty acids after in vitro digestion-fermentation. The results indicated variations in the Zn content and chemical composition of cucumbers according to the treatment groups. The functionalized with Zn and activated SCGs were able to increase Zn levels in cucumbers. Meanwhile, the activated hydrochar obtained at 160 °C and the activated and functionalized with Zn SCGs showed the highest Zn supply per serving. Differences in the antioxidant capacity and short-chain fatty acid production were observed between the groups. It is concluded that the growing conditions and the presence of Zn may significantly influence the contribution of these cucumbers to the dietary intake of nutrients and antioxidants, which could have important implications for human health and nutrition.

Chronic melatonin treatment improves obesity by inducing uncoupling of skeletal muscle SERCA-SLN mediated by CaMKII/AMPK/PGC1α pathway and mitochondrial biogenesis in female and male Zücker diabetic fatty rats

Melatonin acute treatment limits obesity of young Zücker diabetic fatty (ZDF) rats by non-shivering thermogenesis (NST). We recently showed melatonin chronically increases the oxidative status of vastus lateralis (VL) in both obese and lean adult male animals. The identification of VL skeletal muscle-based NST by uncoupling of sarcoendoplasmic reticulum Ca2+-ATPase (SERCA)- sarcolipin (SLN) prompted us to investigate whether melatonin is a SERCA-SLN calcium futile cycle uncoupling and mitochondrial biogenesis enhancer. Obese ZDF rats and lean littermates (ZL) of both sexes were subdivided into two subgroups: control (C) and 12 weeks orally melatonin treated (M) (10 mg/kg/day). Compared to the control groups, melatonin decreased the body weight gain and visceral fat in ZDF rats of both sexes. Melatonin treatment in both sex obese rats restored the VL muscle skin temperature and sensitized the thermogenic effect of acute cold exposure. Moreover, melatonin not only raised SLN protein levels in the VL of obese and lean rats of both sexes; also, the SERCA activity. Melatonin treatment increased the SERCA2 expression in obese and lean rats (both sexes), with no effects on SERCA1 expression. Melatonin increased the expression of thermogenic genes and proteins (PGC1-α, PPARγ, and NRF1). Furthermore, melatonin treatment enhanced the expression ratio of P-CaMKII/CaMKII and P-AMPK/AMPK. In addition, it rose mitochondrial biogenesis. These results provided the initial evidence that chronic oral melatonin treatment triggers the CaMKII/AMPK/PGC1α axis by upregulating SERCA2-SLN-mediated NST in ZDF diabetic rats of both sexes. This may further contribute to the body weight control and metabolic benefits of melatonin.

Total Zn of foods and bioaccesible fractions in the small and large intestine after in vitro digestion and fermentation with fecal material of healthy adults and children: Influence of culinary techniques

The healthy status of human beings is associated with an appropriate nutritional status in Zn, which must firstly be bioavailable. We measured the total Zn amount and its bioaccesibility in raw foods and after cooking by common culinary techniques. These foods were submitted to an in vitro digestion and fermentation with faecal inocula from healthy adults and children to evaluate Zn bioaccesibility in the small and large intestine. Mean total Zn amount provided by foods was 8.080 μg/g. Zn amount released from food in the small intestine was significantly different among several food groups and lower in raw vegetal foods compared to cooked ones (frying, roasting and grilling; p < 0.05); the same behaviour was found in the large intestine for healthy children. Zn bioaccesibility in the large intestine varied statistically according to the subjects' idiosyncrasies, and was higher in healthy children (p < 0.05) probably due to growth demands and different composition of the colonic microbiota. In healthy adults and children, the bioaccesible fractions were 33.0 ± 20.4 % for the small intestine, 16.4 ± 22.0 and 59.6 ± 29.9% for the large one, and the non-bioaccessible ones 50.6 ± 19.9 and 7.4 ± 9.1%, respectively.

Melatonin induces fat browning by transdifferentiation of white adipocytes and de novo differentiation of mesenchymal stem cells

The role of melatonin in obesity control is extensively accepted, but its mechanism of action is still unclear. Previously we demonstrated that chronic oral melatonin acts as a brown-fat inducer, driving subcutaneous white adipose tissue (sWAT) into a brown-fat-like function (beige) in obese diabetic rats. However, immunofluorescence characterization of beige depots in sWAT and whether melatonin is a beige-fat inducer by de novo differentiation and/or transdifferentiation of white adipocytes are still undefined. Lean (ZL) and diabetic fatty (ZDF) Zücker rats were subdivided into two groups, control (C) and oral melatonin-supplemented (M, 10 mg kg^-1 day^-1) for 6 weeks. Mesenchymal stem cells (MSCs) were isolated from both rat inguinal fat and human lipoaspirates followed by adipogenesis assays with or without melatonin (50 nM for 12 h in a 24 h period, 12 h+/12 h-) mimicking the light/dark cycle. Immunofluorescence and western-blot assays showed the partial transdifferentiation of white adipocytes in both ZL and ZDF rats, with increasing thermogenic and beige markers, UCP1 and CITED1 and decreasing white adipocyte marker ASC-1 expression. In addition, melatonin increased UCP1, CITED1, and PGC1-α expression in differentiated adipocytes in both rats and humans. These results demonstrate that melatonin increases brown fat in obese diabetic rats by both adipocyte transdifferentiation and de novo differentiation. Furthermore, it promotes beige MSC adipogenesis in humans. This may contribute to the control of body weight attributed to melatonin and its metabolic benefits in human diabesity.

Ca and Mg Concentrations in Spices and Growth of Commonly Sporulated and Non-Sporulated Food-Borne Microorganisms According to Marketing Systems

Ca and Mg levels were determined in five spices according to marketing system (in bulk or commercialized in glass or polyethylene terephthalate (PET) containers) and correlated with microbial growth of commonly sporulated (Clostridium perfringens and Bacillus cereus) and non-sporulated (Listeria monocytogenes, psychrophilic and mesophilic bacteria, and yeasts and molds) food-borne pathogens present in them, when they were previously added to the microbial culture media. The basil had the highest mean Ca and Mg level and showed the highest microbial growth in the food-borne pathogenic microorganisms studied (p < 0.001). For Ca, the lowest levels were measured in cloves (p < 0.001), which had the lowest capacity for microbial contamination. Ca and Mg contents in spices correlated linear and positively (p < 0.05). Ca concentrations weakly and positively correlated (p < 0.05) with microbial counts for almost all studied microorganisms, and Mg levels for B. cereus, C. perfringens, and mesophilic bacteria (p < 0.05), possibly acting as a growing factor for some sporulated and non-sporulated foodborne pathogens. These relationships are especially significant when PET vs. glass was used as a packaging material for spices.

Development of an Innovative Pressurized Liquid Extraction Procedure by Response Surface Methodology to Recover Bioactive Compounds from Carao Tree Seeds

Nowadays there are evidences from several studies which have revealed the protective effects of food against chronic diseases. These healthy properties have been related to bioactive compounds. Among bioactive substances, the scientific interest in phenolic compounds has stimulated multidisciplinary research on the composition of plant phenolic compounds. The aim of this work has been to determine the bioactive composition of Carao tree seeds (Cassia grandis) and to optimize the recovering of these compounds for developing functional ingredients. To achieve this goal, pressurized liquid extraction (PLE) has been applied to recover these phytochemicals. The optimization of this innovative extraction procedure was performed by a response surface methodology (RSM) based on a central composite design 2³ model to address the bioactive compounds extraction. Phenolic compounds recovered by PLE were characterized using reversed-phase high-performance liquid chromatography coupled to electrospray ionization time-of-flight mass spectrometry (HPLC-ESI-TOF-MS). Analytical characterization allowed the identification and quantitation of phenolic compounds belonging to hydroxybenzoic acids and flavonoids (flavonols, flavanols, flavanones and proanthocyanidins). Phytochemical concentrations were used as response variable in order to get the best extraction conditions. These results pointed out that Carao tree seeds can be a potential source of bioactive compounds and PLE extracts could be used as functional ingredients.

Zn, Cu, and Fe Concentrations in Dehydrated Herbs (Thyme, Rosemary, Cloves, Oregano, and Basil) and the Correlation with the Microbial Counts of Listeria monocytogenes and Other Foodborne Pathogens

Zn, Cu, and Fe concentrations were measured in dehydrated herbs (thyme, rosemary, cloves, oregano, and basil) marketed in bulk or packaged in glass or polyethylene terephthalate (PET). Microbial counts of Listeria monocytogenes and other five foodborne pathogens were also checked when herbs were previously added to the growing media. The highest mean concentrations were found in basil for Zn and Cu, and in thyme and basil for Fe; the lowest ones for these minerals were in cloves (p < 0.05). Basil had significantly higher microbial counts in five of the six foodborne pathogens studied (p < 0.05). Cloves have the best hygienic quality as there is no microbial growth of L. monocytogenes, Clostridium perfringens, and Bacillus cereus; they therefore could be used as a natural preservative in food. Aromatic herbs marketed in bulk showed a significantly higher microbial count (p < 0.05). Zn, Cu, and Fe concentrations were positively correlated with microbial growth for L. monocytogenes, C. perfringens, B. cereus, and psychrophilic microorganisms (p < 0.05), so they could act as a growing factor for the foodborne pathogens.

Phytotoxicity and chelating capacity of spent coffee grounds: Two contrasting faces in its use as soil organic amendment

Spent coffee grounds (SCG) are a bioresidue generated in large amounts worldwide, which could be employed as either fresh or transformed organic soil amendment, by means of different treatments in order to improve its agronomic qualities. An in vitro experiment was conducted in order to evaluate the effect of using different bioamendments derived from spent coffee grounds (SCG) on biomass and Zn, Cu and Fe content of lettuces. Application of 7.5% (w/w) fresh SCG, vermicompost, compost, biochars (at 270 and 400 °C; pyrolysis), SCG washed with ethanol and water, and hydrolysed SCG was carried out in an agricultural soil (Cambic Calcisol). In order to compare with conventional agriculture, the addition of NPK fertilizer was also assessed. Only vermicompost and biochar at 400 °C overcome the growth limitation of SCG. However, these treatments diminished Zn, Cu and Fe concentrations in lettuce probably due to the destruction (microbial degradation/thermal treatment) of natural chelating components (polyphenols). Increase in mineral content was observed in those treatments that did not completely eliminate polyphenols. NPK fertilizer gave rise to lettuces with higher biomass but lower micronutrients content. The results lead us to the possible solution for the use of SCG as organic amendment by vermicomposting and biocharization in order to eliminate toxicity.

Spent coffee grounds improve the nutritional value in elements of lettuce (Lactuca sativa L.) and are an ecological alternative to inorganic fertilizers

The element concentration in lettuces grouped in 5 categories (baby variety, cultivated in agricultural soils with low or high percentages of spent coffee grounds-SCG, without SCG and with NPK) were measured. Lettuces cultivated in agricultural soils amended with SCG had significantly higher levels of several essential (V, Fe, Co, V, and probably Mn and Zn) and toxic elements (Al and probably As), without reaching their toxicological limits. Additionally, blocking of N uptake and therefore plant biomass, and probably Cd absorption from agricultural soil was observed. Organic farming with SCG ameliorates element concentrations in lettuces vs. NPK fertilization. The linear correlations among element uptake and the amendment of SCG could be related with their chelation by some SCG components, such as melanoidins and with the decrease in the soil pH. In conclusion, the addition of SCG produces lettuces with higher element content.

Physicochemical, Nutritional, and Organoleptic Characterization of a Skimmed Goat Milk Fermented with the Probiotic Strain Lactobacillus plantarum C4

The benefits of goat milk, fermented milks, and probiotics for the humans are well documented. In this study, a novel fermented goat milk was manufactured with the putative probiotic strain Lactobacillus plantarum C4 together with L. bulgaricus and Streptococcus thermophilus. Ultrafiltration was chosen as the skimmed milk concentration method because it produced the best viscosity and syneresis and a high casein content. The viability rate of all bacterial strains was >10⁷ cfu/mL, even after 5 weeks of storage or after in vitro gastrointestinal digestion, which is especially important for exertion of the probiotic strain functionalities. This fermented milk is also a good source of nutrients, having a low lactose and fat content, high protein proportion, and good mineral concentration. According to these data and the overall acceptability described by panelists, this fermented milk is a healthy dairy product comparable with commercially available fermented milks.

Bioaccessible peptides released by in vitro gastrointestinal digestion of fermented goat milks

In this study, ultrafiltered goat milks fermented with the classical starter bacteria Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarus subsp. thermophilus or with the classical starter plus the Lactobacillus plantarum C4 probiotic strain were analyzed using ultra-high performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) and/or high performance liquid chromatography-ion trap (HPLC-IT-MS/MS). Partial overlapping of the identified sequences with regard to fermentation culture was observed. Evaluation of the cleavage specificity suggested a lower proteolytic activity of the probiotic strain. Some of the potentially identified peptides had been previously reported as angiotensin-converting enzyme (ACE) inhibitory, antioxidant, and antibacterial and might account for the in vitro activity previously reported for these fermented milks. Simulated digestion of the products was conducted in the presence of a dialysis membrane to retrieve the bioaccessible peptide fraction. Some sequences with reported physiological activity resisted digestion but were found in the non-dialyzable fraction. However, new forms released by digestion, such as the antioxidant α_s1-casein ¹⁴⁴YFYPQL¹⁴⁹, the antihypertensive α_s2-casein ⁹⁰YQKFPQY⁹⁶, and the antibacterial α_s2-casein ¹⁶⁵LKKISQ¹⁷⁰, were found in the dialyzable fraction of both fermented milks. Moreover, in the fermented milk including the probiotic strain, the k-casein dipeptidyl peptidase IV inhibitor (DPP-IV) ⁵¹INNQFLPYPY⁶⁰ as well as additional ACE inhibitory or antioxidant sequences could be identified. With the aim of anticipating further biological outcomes, quantitative structure activity relationship (QSAR) analysis was applied to the bioaccessible fragments and led to potential ACE inhibitory sequences being proposed. Graphical abstract Ultrafiltered goat milks were fermented with the classical starter bacteria (St) and with St plus the L. plantarum C4 probiotic strain. Samples were analyzed using HPLC-IT-MS/MS and UPLC-Q-TOF-MS/MS. After simulated digestion and dialysis, some of the active sequences remained and new peptides with reported beneficial activities were released.

Antioxidant, ACE-inhibitory and antimicrobial activity of fermented goat milk: activity and physicochemical property relationship of the peptide components

Increasing evidence on goat milk and the health benefits of its derived products beyond its nutritional value show its potential as a functional food. In this study, goat milk fractions were tested for their total antioxidant capacity using different methods (ORAC, ABTS, DPPH and FRAP), as well as their angiotensin-I-converting-enzyme inhibitory and antimicrobial (against Escherichia coli and Micrococcus luteus) activities. Different whey fractions (whey, cation exchange membrane permeate P and retentate R) of two fermented skimmed goat milks (ultrafiltered goat milk fermented with the classical starter bacteria or with the classical starter plus the Lactobacillus plantarum C4 probiotic strain) were assessed. Additionally, P fractions were divided into two sub-fractions after being passed through a 3 kDa cut-off membrane: (a) the permeate with peptides of MW <3 kDa (P < 3); and (b) the retentate with peptides and proteins of MW >3 kDa (P > 3). No differences in biological activities were observed between the two fermented milks. However, the biological peptides present in the P < 3 fraction showed the highest total antioxidant capacity (for the ORAC assay) and angiotensin-I-converting-enzyme inhibitory activity. Those present in the R fraction showed the highest total antioxidant capacity against ABTS˙⁺ and DPPH˙ radicals. Some antimicrobial activity against E. coli was observed for the fermented milk containing the probiotic, which could be due to some peptides being released by the probiotic strain. In conclusion, small and non-basic bioactive peptides could be responsible for most of the angiotensin-I-converting-enzyme inhibitory and antioxidant activities. These findings reinforce the potential benefits of the consumption of fermented goat milk in the prevention of cardiovascular diseases associated with oxidative stress and hypertension.

Increased Serum Al Levels in Hemodialysis Patients Kept Enhanced during a 2-Year Prospective Study

The regulation of mineral homeostasis is altered in hemodialysis patients with renal insufficiency, producing increased risk for secondary diseases like cardiovascular ones. We hypothesized that risen serum aluminum (Al) concentration in hemodialysis patients kept enhanced during a 2-year longitudinal study is associated with enhanced cardiovascular risk and influenced by medical treatments. This study reports the prospective monitoring of serum Al levels in six-monthly samplings over 2 years in 116 hemodialysis patients and a control group of 50 healthy adults. The influence of other factors like sex, age, kidney transplant, disease etiology, and drug consumption was also considered. At each sampling, serum Al levels were significantly higher in the patients than in the healthy controls (P < 0.05). Levels in the patient group were statistically significantly lower at the third and fourth versus first and second samplings, which may be related to Al accumulation in tissues. Increased Al levels in patients were positively and significantly related to serum calcium (Ca) and uric acid levels. Serum Al concentrations were significantly lower in patients receiving vasodilators and diuretics. Higher serum Al levels in hemodialyzed patients administered with phosphate binders or anti-hyperkalemics are attributable to their usual Al salt content. The consumption of antianemic drugs increases Al absorption by forming more bioavailable complexes with the compounds in these drugs. In conclusion, this is the first study to indicate that cardiovascular problems associated with elevated serum Al levels in hemodialysis patients may be in part mitigated by administrating vasodilators and diuretics, which reduce these levels.

Ulcerative Colitis and Crohn's Disease Are Associated with Decreased Serum Selenium Concentrations and Increased Cardiovascular Risk

The incidence of inflammatory bowel disease (IBD) and associated oxidative stress is increasing. The antioxidant mineral selenium (Se) was measured in serum samples from 106 IBD patients (53 with ulcerative colitis (UC) and 53 with Crohn’s disease (CD)) and from 30 healthy controls. Serum Se concentrations were significantly lower in UC and CD patients than in healthy controls (p < 0.001) and significantly lower in CD patients than in UC patients (p = 0.006). Se concentrations in patients were significantly influenced by sex, body mass index (BMI), the inflammatory biomarker α-1-antitrypsin, surgery, medical treatment, the severity, extent, and form of the disease and the length of time since onset (p < 0.05). Se concentrations in IBD patients were positively and linearly correlated with nutritional (protein, albumin, prealbumin, cholinesterase and total cholesterol) and iron status-related (hemoglobin, Fe and hematocrit) parameters (p < 0.05). A greater impairment of serum Se and cardiovascular status was observed in CD than in UC patients. An adequate nutritional Se status is important in IBD patients to minimize the cardiovascular risk associated with increased inflammation biomarkers, especially in undernourished CD patients, and is also related to an improved nutritional and body iron status.

Melatonin increases intracellular calcium in the liver, muscle, white adipose tissues and pancreas of diabetic obese rats

Melatonin, a widespread substance with antioxidant and anti-inflammatory properties, has been found to act as an antidiabetic agent in animal models, regulating the release and action of insulin. However, the molecular bases of this antidiabetic action are unknown, limiting its application in humans. Several studies have recently shown that melatonin can modify calcium (Ca(2+)) in diabetic animals, and Ca(2+) has been reported to be involved in glucose homeostasis. The objective of the present study was to assess whether the antidiabetic effect of chronic melatonin at pharmacological doses is established via Ca(2+) regulation in different tissues in an animal model of obesity-related type 2 diabetes, using Zücker diabetic fatty (ZDF) rats and their lean littermates, Zücker lean (ZL) rats. After the treatments, flame atomic absorption spectrometry was used to determine Ca(2+) levels in the liver, muscle, main types of internal white adipose tissue, subcutaneous lumbar fat, pancreas, brain, and plasma. This study reports for the first time that chronic melatonin administration (10 mg per kg body weight per day for 6 weeks) increases Ca(2+) levels in muscle, liver, different adipose tissues, and pancreas in ZDF rats, although there were no significant changes in their brain or plasma Ca(2+) levels. We propose that this additional peripheral dual action mechanism underlies the improvement in insulin sensitivity and secretion previously documented in samples from the same animals. According to these results, indoleamine may be a potential candidate for the treatment of type 2 diabetes mellitus associated with obesity.

[HYPOTENSIVE EFFECT OF AN EXTRACT OF BIOACTIVE COMPOUNDS OF OLIVE LEAVES: PRELIMINARY CLINICAL STUDY]

OBJECTIVE

to evaluate the possible hypotensive effect in pre-hypertensive and hypertensive subjects of an olive leaf extract (OLE) standardized to 15% (w/w) in oleoeuropein, and with a 10% (w/w) mean content of triterpenic acids and 1% (w/w) in hydroxytirosol. Moreover, the possible effects on the blood antioxidant status and lipid profile have been also evaluated.

MATERIALS AND METHODS

this interventional study has been performed in human volunteers, to whom 1 600 mg OLE/days, was administered. The analyzed parameters at the beginning and end of the study were diastolic and systolic pressure, delay in the LDL-cholesterol oxidation "lag time" and blood levels of nitric oxide (NO), malonic dialdehyde (MDA), antioxidant capacity (AOC) lipid profile, glucose, transaminases and creatinine.

RESULTS

a decrease in the diastolic and systolic pressure, and an increase in the NO values all statistically significant (CHO) for all volunteers, was found. In volunteers with higher systolic pressure their levels were also significantly diminished after the intervention trial (P = 0,002). The LDL lag time increased significantly (P = 0,047). Additionally, in all volunteers CHO levels were significantly decreased, and those of LDL cholesterol, triglycerides (TG) and the CHO/HDL cholesterol ratio were diminished with a tendency to the significance (P = 0,076; P = 0,059; P = 0,056; respectively).

CONCLUSIONS

this preliminary study reports by the first time the positive influence of the OLE assayed in the regulation of the hypertension, LDL lag time and blood lipid profile. Therefore, further studies are of great interest.

Does Lactobacillus plantarum or ultrafiltration process improve Ca, Mg, Zn and P bioavailability from fermented goats' milk?

Ca, Mg, Zn and P bioavailability from two experimental ultrafiltered fermented goats' milks (one of them with the probiotic Lactobacillus plantarum and another one without it), and fermented goats' milk samples available in the market were evaluated. Solubility, dialysability and a model combining simulated gastrointestinal digestion and mineral retention, transport and uptake by Caco-2 cells were used to assess bioavailability. The highest Ca, Mg, Zn and P bioavailability values always corresponded to the fermented milk developed by our research group, which could be explained by the effect of milk ultrafiltration. The fermented milk with L. plantarum showed higher Ca retention than the ones without the microorganism, and major Ca uptake when compared to commercial products. This fact could be attributed to a positive effect exerted by the probiotic strain.

Activity of melatonin against Leishmania infantum promastigotes by mitochondrial dependent pathway

Visceral leishmaniasis, a potentially fatal disease, remains a major international health problem. Only a limited number of effective antileishmanial agents are available for chemotherapy, and many of them are expensive with severe side effects or have a markedly reduced effectiveness due to the development of drug resistance. Hence, there is a genuine need to develop a novel effective and less toxic antileishmanial drug. Melatonin, a neurohormone found in animals, plants, and microbes, can participate in various biological and physiological functions. Several in vitro or in vivo studies have reported the inhibitory effect of melatonin against many parasites via various mechanisms, including modulation of intracellular concentrations of calcium in the parasite and/or any other suggested mechanism. Importantly, many of available antileishmanial drugs have been reported to exert their effects by disrupting calcium homeostasis in the parasite. The objective of the present study was to test the efficacy of exogenous melatonin against Leishmania infantum promastigotes in vitro. Interestingly, melatonin not only demonstrated a significant antileishmanial activity of against promastigote viability in tested cultures but was also accompanied by an alteration of the calcium homeostasis of parasite mitochondrion, represented by earlier mitochondrial permeability transition pore opening, and by changes in some mitochondrial parameters are critical to parasite survival. These pioneering findings suggest that melatonin may be a candidate for the development of novel effective antileishmanial agents either alone or in associations with other drugs.

Serum Zn levels and Cu/Zn ratios worsen in hemodialysis patients, implying increased cardiovascular risk: a 2-year longitudinal study

The objective of this study was to analyze serum Zn and Cu concentrations and Cu/Zn ratios in 116 hemodialysis patients (HPs) over a 2-year longitudinal study at four time points (6-month intervals). The relation exerted on these values by 26 biochemical and nutritional indexes, the age and drug consumption of the patients, and the etiology of their disease were also evaluated. A healthy control group (n = 50) was also studied. Mean serum Zn concentrations were lower (p = 0.009) and the Cu/Zn ratios higher (p = 0.009) in HPs than in controls. Serum Cu levels in HP did not differ to those of controls. At all four sampling times, the mean serum Zn levels and Cu/Zn ratios were lower and higher, respectively, in HPs than in the controls. There was a significant reduction in serum Zn levels and an increase in Cu concentrations and Cu/Zn ratios in HPs from the second to the fourth sampling. Serum Zn levels of the HPs diminish with age older than 50 years. Serum Cu levels were significantly higher in patients consuming antihypercalcemic or anti-infarction drugs, whereas serum Cu levels and Cu/Zn ratios were significantly lower in those treated with diuretics. Diminished Zn levels were negatively correlated with low-density lipoprotein (LDL) cholesterol in HPs; however, enhanced Cu/Zn ratios were positively correlated with total cholesterol and LDL cholesterol. Both findings indicate an increased cardiovascular risk. We conclude that this study contributes the first evidence of a correlation between marked dyslipidemia and worsened Cu/Zn ratios in HPs, implying an increased risk of diseases associated with elevated oxidative stress, inflammation, and depressed immune function, such as cardiovascular diseases.

[Effects on the lipid profile in humans of a polyphenol-rich carob (Ceratonia siliqua L.) extract in a dairy matrix like a functional food; a pilot study]

The design of functional foods enriched in nutrients that favorably alter the lipid profile to prevent cardiovascular diseases and stimulate bowel function is of great interest. We have assayed a non-extractable-tannates-rich carob-fiber (PF-1®) in a milk matrix developed by Biosearch S.A. to discover its effects on the lipid profile and bowel function of human volunteers. A 4-week interventional study (400 mL daily consumption of this functional food, containing 20 g of PF-1®/L), was conducted: blood samples were analyzed for lipid profile, glucose, transaminases, creatinine and fat-soluble vitamins. The body-mass index and bowel function of the participants in the study were also measured. A tendency for triglyceride levels to diminish was observed in all participants (P = 0.066), and in the normal-cholesterol group in particular (P = 0.078). Another tendency to total cholesterol levels fell in the hypercholesterolemic group (P = 0.061) was also found. In the normal-cholesterol group, total cholesterol (CT), HDL-cholesterol and LDL-cholesterol levels significantly increased with the consumption of the functional food (P < 0.05). A better bowel function was also recorded by volunteers. This preliminary study highlights the possible positive influence of this functional food on the regulation of the lipid profile and bowel function in humans.

Melatonin ameliorates low-grade inflammation and oxidative stress in young Zucker diabetic fatty rats

The aim of this study was to investigate the effects of melatonin on low-grade inflammation and oxidative stress in young male Zucker diabetic fatty (ZDF) rats, an experimental model of metabolic syndrome and type 2 diabetes mellitus (T2DM). ZDF rats (n = 30) and lean littermates (ZL) (n = 30) were used. At 6 wk of age, both lean and fatty animals were subdivided into three groups, each composed of 10 rats: naive (N), vehicle treated (V), and melatonin treated (M) (10 mg/kg/day) for 6 wk. Vehicle and melatonin were added to the drinking water. Pro-inflammatory state was evaluated by plasma levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP). Also, oxidative stress was assessed by plasma lipid peroxidation (LPO), both basal and after Fe(2+)/H2O2 inducement. ZDF rats exhibited higher levels of IL-6 (112.4 ± 1.5 pg/mL), TNF-α (11.0 ± 0.1 pg/mL) and CRP (828 ± 16.0 µg/mL) compared with lean rats (IL-6, 89.9 ± 1.0, P < 0.01; TNF-α, 9.7 ± 0.4, P < 0.01; CRP, 508 ± 21.5, P < 0.001). Melatonin lowered IL-6 (10%, P < 0.05), TNF-α (10%, P < 0.05), and CRP (21%, P < 0.01). Basal and Fe(2+)/H2O2-induced LPO, expressed as malondialdehyde equivalents (µmol/L), were higher in ZDF rats (basal, 3.2 ± 0.1 versus 2.5 ± 0.1 in ZL, P < 0.01; Fe(2+)/H2O2-induced, 8.7 ± 0.2 versus 5.5 ± 0.3 in ZL; P < 0.001). Melatonin improved basal LPO (15%, P < 0.05) in ZDF rats, and Fe(2+)/H2O2- induced LPO in both ZL (15.2%, P < 0.01) and ZDF rats (39%, P < 0.001). These results demonstrated that oral melatonin administration ameliorates the pro-inflammatory state and oxidative stress, which underlie the development of insulin resistance and their consequences, metabolic syndrome, diabetes, and cardiovascular disease.

The probiotic bacterial strain Lactobacillus fermentum D3 increases in vitro the bioavailability of Ca, P, and Zn in fermented goat milk

We determined calcium, magnesium, phosphorus and zinc levels in a total of 27 samples of commercial goat- and cow-milk fermented products and 9 samples of a goat-milk fermented product with addition of a probiotic bacterial strain, Lactobacillus fermentum D3, manufactured experimentally by our research group. Atomic absorption spectroscopy with flame atomization and UV/VIS spectrophotometry were used as analytic techniques. The results of an in vitro digestion process showed that the bioavailability of calcium, phosphorus, and zinc was significantly higher in our fermented milk containing the probiotic bacterial strain than it was in commercial goat-milk fermented products. Furthermore, our product showed a significantly higher bioavailability of calcium and zinc compared to goat- and cow-milk fermented products made with other microorganisms. We conclude that, in in vitro assays, strain D3 seems to increase the bioavailability of these minerals and that this new product may constitute a better source of bioavailable minerals compared to other products already on the market.

Altered serum selenium and uric acid levels and dyslipidemia in hemodialysis patients could be associated with enhanced cardiovascular risk

In the present study, the first objective was to follow up serum selenium (Se) concentrations in 117 hemodialysis patients (HPs) during a 2-year longitudinal study, relating concentrations to biochemical indexes (n = 6; namely lipoprotein profile, uric acid, and total protein levels). It was also evaluated whether the disease is associated with an enhanced cardiovascular risk. A healthy control group (n = 50) was also studied. Mean serum Se levels were significantly lower in HPs than in the controls (p = 0.002); mean levels significantly increased from the first to third blood sampling (p < 0.001). HPs showed a marked dyslipidemia, with a significant reduction in total cholesterol, low-density lipoprotein, and high-density lipoprotein cholesterol levels and a significant increase in triglyceride levels (p < 0.001). HPs showed a marked hyperuricemia (p < 0.001). Serum selenium levels in HPs were correlated negatively with uric acid levels (inflammation biomarker; p < 0.01). In HPs, serum Se levels are reduced due to their disease (chronic renal failure). Serum Se levels rose until the third blood sampling. The marked dyslipidemia and hyperuricemia found in HPs and the negative correlation between the serum Se and uric acid levels in these patients could imply an enhanced cardiovascular risk.

Beneficial effects of melatonin on obesity and lipid profile in young Zucker diabetic fatty rats

The study objective was to investigate the effects of melatonin on obesity and obesity-associated systolic hypertension and dyslipidemia in young male Zucker diabetic fatty (ZDF) rats, an experimental model of the metabolic syndrome. ZDF rats (n=30) and lean littermates (ZL) (n=30) were used. At 6wk of age, both lean and fatty animals were subdivided into three groups (n=10): naive (N), vehicle-treated (V), and melatonin-treated (M) (10mg/kg/day) for 6wk. Vehicle and melatonin were added to the drinking water. Melatonin reduced mean weight gain (51±2/100g BW) versus N-ZDF group (58±3, P<0.05) without food intake differences. M-ZDF rats showed an apparent reduction in systolic hypertension that proved not to be statistically significant, and a significant improvement in dyslipidemia, with a reduction in hypertriglyceridemia from 580±40 to 420.6±40.9mg/dL (P<0.01). Melatonin raised high-density-lipoprotein (HDL) cholesterol in ZDF (from 81.6±4.9 to 103.1±4.5mg/dL, P<0.01) and ZL rats (from 62.8±4.8 to 73.5±4.8mg/dL, P<0.05) and significantly reduced low-density-lipoprotein (LDL) cholesterol in ZDF rats from 5.20±0.4 to 4.14±0.3 mg/dL (P<0.05) but had no effect on total cholesterol levels. To our knowledge, this is the first evidence of a positive effect of melatonin on overweight and lipid pattern of obese Zucker diabetic rats, supporting the proposition that melatonin administration may ameliorate overweight and lipid metabolism in humans. Because these benefits occurred in youth, before advanced metabolic and vascular complications, melatonin might help to prevent cardiovascular disease associated with obesity and dyslipidemia.

Serum selenium levels in cirrhotic patients are not influenced by the disease severity index

Selenium (Se) is an antioxidant element that protects against cellular damage by reactive oxygen species. Therefore, total serum Se concentration may reflect protection during the development of cirrhosis, an oxidative stress-related disease. We hypothesized that serum Se levels are diminished in cirrhotic patients due to their enhanced oxidative stress, and serum Se levels are reduced the most in patients with the highest severity of cirrhosis. A case-control study was performed to determine whether cirrhosis is associated with changes in serum Se levels. Blood samples from 30 healthy controls and 93 cirrhotic patients were analyzed for total serum Se by hydride generation atomic absorption spectrometry. The Child-Pugh index score was used to evaluate the severity of liver disease. The mean serum Se concentration was significantly lower in patients vs controls (0.721 ± 0.239 vs 0.926 ± 0.241 μmol/L; P = .001). Mean serum Se levels were not significantly lower in patients with higher severity of cirrhosis (0.691 ± 0.229 vs 0.755 ± 0.255 μmol/L; P = .144). A positive and significant correlation was found between age and serum Se levels in patients (r = 0.277, P = .007). Patients showed significant sex differences in serum Se level (higher in male) and severity index (higher in female). The significantly decreased serum Se level in patients indicates that the Se component of the antioxidant system is severely impaired in cirrhosis. However, serum Se levels were not influenced by the severity of the disease.

PTH increases jaw mineral density in a rabbit model of osteoporosis

Intermittent parathyroid hormone (PTH) administration has been shown to be a promising therapy for systemic bone loss. Accordingly, we hypothesized that PTH could have positive results in treating oral complications of osteoporosis. Hence, we evaluated both mandibular bone loss and its response to PTH in a rabbit model of osteoporosis induced by ovariectomy and glucocorticoid administration. There was a significant and marked decrease in bone mineral density (BMD), bone mineral content (BMC), and calcium content in ash from the osteoporotic peri-alveolar region, which influenced global jaw loss. Remarkably, PTH (1-34) administration to osteoporotic rabbits almost completely reversed BMD, BMC, and calcium content fall in the peri-alveolar region, subsequently reducing global mandibular bone loss. Thus, although the peri-alveolar region is particularly susceptible to osteoporosis, it also responds well to intermittent PTH. Therefore, these results suggest that PTH might represent a valid therapy for improving the osseointegration of dental implants in persons with osteoporosis.

Magnesium and calcium contents in foods from SE Spain: influencing factors and estimation of daily dietary intakes

The magnesium and calcium content (fresh weight basis) of 243 food, 69 beverages and 11 potable water samples were determined using flame atomic absorption spectrometry. Analyses of NIST and CBR-CEC reference materials demonstrated the reliability and accuracy of this technique. The highest magnesium and calcium levels corresponded to molluscs and crustacea, and dairy products, respectively. Magnesium concentrations found in different food groups were significantly and linearly related with corresponding calcium levels (P<0.001) with the exception of fish products. Significant linear relationships among magnesium and calcium concentrations, and fiber content for cereals, legumes and dry-fruits were found (P<0.001); however, total fat contents of considered foods were not related (P>0.05) with levels of elements considered. Significant linear relationships among magnesium and calcium concentrations in cereals, legumes and fruits, and protein content were found (P<0.001). In meat and by-products, magnesium concentrations found in organ meats were significantly lower (P<0.01); for calcium, levels measured in sausages were significantly higher (P<0.001) than those found in meats and organ meats. In fish products, magnesium levels in molluscs and crustacea were significantly higher than those measured in fish and cephalopoda (P<0.001); for calcium, concentrations in cephalopoda were significantly lower (P<0.001). Mean magnesium and calcium concentrations analyzed in cheese were statistically higher than those determined in other dairy products (P<0.01). In alcoholic drinks, magnesium and calcium levels measured in distilled beverages (whisky, gin, rum, brandy and alcoholic liquors) were statistically lower than those found in fermented types (wine and beer) (P<0.01). The daily intake of magnesium and calcium in the Spanish diet was 366.1 and 1266.6 mg/day per person, respectively. Results revealed that the intake of analyzed elements was similar to recommended dietary allowances.

Selenium concentrations in serum of individuals with liver diseases (cirrhosis or hepatitis): relationship with some nutritional and biochemical markers

Serum concentrations were measured in individuals (n = 50) with liver diseases (cirrhosis and hepatitis) by hydride generation atomic absorption spectrometry in a cross-sectional study. Mean serum selenium levels determined in patients with cirrhosis (n = 12) or with hepatitis (n = 38) were significantly lower (P<0.01) than those measured in control groups mainly due to a decreased liver function. Mean serum selenium concentrations were significantly lower in cirrhotic individuals when compared with patients with hepatitis (P<0.05). Therefore, the severity of the live injury is a factor conditioning the impairment in the selenium body status observed in individuals with hepatopathies. In hepatic patients serum total cholesterol levels showed a significant correlation with serum selenium concentrations (r=0.912, P<0.05) demonstrating the important role of selenium as an antioxidant agent; similarly, gamma-glutamic-transferase levels were significantly correlated with the serum selenium levels (r=-0.803, P<0.05) indicating that when the intensity of the hepatic injury increases (enhancement in serum GGT levels) concomitantly the serum selenium levels decrease significantly. No significant relationships between serum selenium levels and sex or age of patients were observed.

Determination of zinc levels in waters from southeastern Spain by electrothermal atomic absorption spectrometry: relationship with industrial activity

An efficient method for the determination of nanogram levels of zinc in waters (potable, irrigation, waste and sea waters) is described. Acidified water samples were analyzed by an accurately optimized time/temperature program for electrothermal atomic absorption spectrometry. The samples were previously treated with a matrix modifier consisting of 0.1% Mg(NO3)2 in 0.5 M HNO3 and injected through a graphite tube with L'Vov platform. Sample recoveries, repeteability, and analyses of NIST reference material demonstrated the reliability and accuracy of this technique. Zinc concentrations ranged from 2.0 to 73.0 microg l(-1). No significant differences among the mean zinc levels determined in the four types of water considered from southeastern Spain were found. Zinc concentrations in waters from the zone were not affected by human and industrial activity.

Essentiality of selenium in the human body: relationship with different diseases

In the present review different aspects related to the essential element selenium in the human organism are considered. A large number of human studies have been performed in order to improve knowledge on the influence of this element in the origin and development of several degenerative diseases. Selenium deficiencies among human beings as well as animals are being recognized worldwide to be related to a number of pathologies. This element has also the special characteristic that the range between its essential and toxic character is very close, and consequently daily dietary intake should be appropriately monitored in individuals. Nevertheless, nowadays there is still a lot of controversy about the optimum dietary level of this element in order to cure or to prevent the appearance of diseases such as cirrhosis, cancer, diabetes, or cardiovascular pathologies. Results obtained in several animal and epidemiological studies have indicated that Se could constitute a dietary factor with protective action against several degenerative diseases.

Serum and urine selenium concentrations in patients with cardiovascular diseases and relationship to other nutritional indexes

Serum and urine selenium levels were determined in patients with cardiovascular diseases by hydride generation atomic absorption spectrometry. Mean serum Se concentrations measured in patients with acute myocardial infarction (AMI; n = 32) or with ischemic cardiomyopathy (n = 50) were significantly lower than those determined in control groups. In AMI patients, serum triglyceride levels showed a positive significant correlation with the serum Se concentration (r = 0.59, p < 0.05). This result reinforces the important role of Se as an antioxidant agent in this disease. Mean urine Se concentrations of AMI patients (n = 33) were also significantly lower to those determined in the control group (p < 0. 05). This reaction of the organism contributes to regulate the Se homeostasis to keep the body Se status as high as possible.

Serum and urine selenium concentrations as indicators of body status in patients with diabetes mellitus

Serum and urine selenium levels were determined in patients with diabetes by hydride generation atomic absorption spectrometry. Mean serum selenium concentrations measured in patients with diabetes mellitus (64.9 +/- 22.8 micrograms/l) were significantly lower than those determined in the control group (74.9 +/- 27.3 micrograms/l) (P < 0.05). Mean serum selenium concentrations were not significantly different between the two groups of diabetic patients considered (P > 0.05). Mean urine selenium concentration in diabetic patients (18.8 +/- 10.7 micrograms/l) were not significantly different from those measured in the control group (20.2 +/- 10.1 micrograms/l) (P < 0.05). No significant differences in serum and urine selenium levels were found if related to sex of patients (P > 0.05). Application of linear regression analysis to serum and urine selenium levels and patients' age showed a non-statistically significant correlation (P > 0.05). Given the marked overlap between the two ranges of the populations, the predictive values of serum selenium in diabetic patients are low.

Urine arsenic concentrations in healthy adults as indicators of environmental contamination: relation with some pathologies

Arsenic concentrations were determined in 126 urine samples by hydride generation atomic absorption spectrometry. Samples were mineralized with nitric acid in a thermostated mineralization block. This technique was compared with a method that involves mineralization in a microwave digestion bomb. A mean recovery percentage of 100.80 +/- 5.57% was obtained. The relative standard deviation ranged from 1.7 to 10.52%. It was found that subject sex and age did not affect urine As levels (P > 0.05). The mean urine As levels in patients with hepatic injury (4.24 +/- 1.98 micrograms/l), diabetes (3.44 +/- 2.36 micrograms/l) and myocardial infarction (3.64 +/- 1.85 micrograms/l) were not statistically different (P > 0.05) to that found in the control group (healthy subjects) (3.68 +/- 2.27 micrograms/l). This result could be related to the fact that the regulation of As in the human organism is independent of these diseases. Measured As concentrations in the eight basic health zones of the study area were not statistically different (P > 0.01). This fact demonstrates the existence of a similarly low environmental As distribution in coastal and mountainous zones.

Serum selenium levels as indicators of body status in cancer patients and their relationship with other nutritional and biochemical markers

A cross-sectional study of serum selenium levels in patients (n = 59) with different types of cancer from southeastern Spain was carried out using hydride generation atomic absorption spectrometry. The subjects were divided into four groups according to the cancer location (respiratory, digestive, haematological and gynaecological groups). Serum selenium levels in all patients (54.41 +/- 24.80 mg/l) were significantly lower (P < 0.001) than those determined in control groups [healthy subjects from the same area (n = 130) and institutionalized elderly people (n = 93)]. Mean serum selenium concentrations were not significantly different among the four groups considered (P > 0.05). Linear regression analyses performed on serum selenium levels and biochemical markers (total cholesterol, triglycerides, transaminases, uric acid and urea) did not establish any statistically significant correlation (P > 0.05). No significant relationships between serum selenium concentrations and sex or age of patients was observed (P > 0.05). Given the marked overlap between the two ranges of the populations (the means are within approx. 1/2 S.D.) the predictive values of serum selenium are low. Thus, there is indeed a statistical significance between the means, but selenium cannot be used to determine whether or not a patient has cancer disease.

Serum zinc and copper concentrations and Cu/Zn ratios in patients with hepatopathies or diabetes

The serum zinc and copper levels, as well as Zn/Cu ratios, were determined in 30 patients (18 with diabetes and 12 with hepatopathies) and compared to healthy-age matched controls by atomic absorption spectrometry. Serum Zn (0.946 +/- 0.302 mg/l) and Cu (0.952 +/- 0.355 mg/l) concentrations were not significantly different in patients with hepatopathies as compared to controls (p > 0.05). Serum Zn concentrations (0.778 +/- 0.164 mg/l) were significantly lower in diabetic patients than those determined in controls (p < 0.01). In contrast, Cu levels (0.987 +/- 0.305 mg/l) were not significantly different (p > 0.05) than in controls. Serum Cu/Zn ratios were not significantly different in patients with diabetes or hepatopathies than those measured in healthy controls (p > 0.05). In patients, no statistically significant differences were observed in the Zn, Cu and Cu/Zn with respect to sex (p > 0.05) or age (p > 0.05).

Zinc and copper concentrations in serum from Spanish women during pregnancy

A cross-sectional study of serum zinc (Zn) and copper (Cu) levels in 31 healthy pregnant women and 51 healthy, nonpregnant controls living in the Mediterranean area of Granada, Spain, was performed. The subjects were divided into two groups: Group A, consisted of pregnant women in three categories according to the trimester of pregnancy, and Group B consisted of nonpregnant women acting as controls. In pregnant women, serum Zn levels were found from 0.300-1.340 mg/L and serum Cu from 0.936-2.304 mg/L, whereas in the nonpregnant women group, the mean serum levels were 0.947+/-0.265 mg/L for Zn and 1.092+/-0.365 mg/L for Cu. Serum Zn progressively decreased with gestation. Mean Zn levels were 0.829+/-0.253, 0.846+/-0.329, and 0.620+/-0.142 mg/L, corresponding to the first, second, and third trimesters of pregnancy, respectively. Serum Zn concentrations were significantly lower in pregnant women as compared to controls: 0.712+/-0.236 mg/L vs 0.947+/-0.265 mg/L, respectively (p < 0.05). In contrast, Cu levels increased with period of gestation from 1.053+/-0.498 mg/L in the first trimester to 1.616+/-0.304 mg/L in the second and 1.689+/-0.344 mg/L in the third. Serum Cu levels in the second and third trimesters of pregnancy were significantly higher (p < 0.05) than those determined during the first trimester and for nonpregnant controls. Both Zn and Cu during pregnancy did not appear to be dependent on the subject's age (p > 0.05).

Serum zinc levels in healthy subjects from southeastern Spain

The serum zinc (Zn) concentrations of 80 healthy subjects (48 male, 32 female) from southeastern Spain were determined by atomic absorption spectrometry. The samples were digested by heating in a 4:1 mixture of nitric and perchloric acids. The concentration of Zn was determined against a Contox Trace Metal Serum Control Panel A standard reference. Zn concentrations in the standard were found to be 2.332+/-0.489 mg/L, with a mean recovery of 102.7%. In the serum samples, the relative standard deviation was <6% for the range of concentrations determined: 0.420-1.540 mg/L for women (mean value 0.947+/-0.265 mg/L) and 0.490-1.480 mg/L for men (mean value 0.951+/-0.243 mg/L). In healthy subjects, no statistically significant differences were observed in the Zn levels with respect to their sex (p > 0.05) or the location where they lived (mountainous vs coastal zones). It is concluded that the dietary Zn intake and Zn status for healthy adults in this region of Spain are within normal values.

Serum copper and zinc concentrations in serum from patients with cancer and cardiovascular disease

A single cross-sectional study for serum copper and zinc levels was evaluated in 20 patients with cancer (respiratory, digestive, haematological, gynaecological) and 21 patients with cardiopathy (acute myocardial infarction and ischemic cardiomyopathy). A control group of 84 healthy subjects was selected. The mean serum zinc levels in patients with gynaecological cancer and ischemic cardiomyopathy were significantly lower than the control group (P < 0.05). However, the mean serum copper level was not statistically different among patients with cancer (P < 0.05) and cardiomyopathy (P > 0.05) than the control group. Male patients did not have statistically different values for serum Cu (P > 0.05) and Zn (P < 0.05) than those found in female patients. Patients' age did not have any statistical influence (P > 0.05) on serum Cu and Zn levels.

Determination of copper levels in serum of healthy subjects by atomic absorption spectrometry

Copper levels in serum samples of 84 healthy subjects living in southeastern Spain were determined using the flame atomic absorption spectrometry technique. Mineralization of samples was carried out with an HNO3/HClO4 (4:1) mixture in a thermostated mineralization block. The accuracy of the method was tested by using a standard reference material. A mean recovery percentage of 104.70% was obtained. The relative standard deviation (R.S.D.) as a measurement of the precision of the method was lower than 5% in the concentration range considered. Mean copper concentrations were 1.092 +/- 0.365 mg/l (with the range 0.304-2.000 mg/l) and 1.113 +/- 0.253 mg/l (corresponding to an interval of 0.648-1.760 mg/l) for women and men, respectively. There are no significant differences between the copper levels in serum according to either sex or geography zone (P > 0.05). For example, there were no differences of copper levels in serum of subjects from coastal and mountainous zones. Estimated daily dietary intakes on copper in women and men were 1.38 and 2.10 mg Cu/day respectively.

Determination of selenium in cereals, legumes and dry fruits from southeastern Spain for calculation of daily dietary intake

Hydride generation atomic absorption spectrometry was used to determine selenium content in cereals, legumes and dry fruits from the coast of the province of Granada (southeastern Spain). Accuracy was assured using both a NIST SRM 1572 and recovery experiments. The precision expressed as relative standard deviation (R.S.D.) varied between 6.50% for seeds and 15.98% for bread. The highest selenium concentrations were found for dry fruits (294.6 ng/g), followed by legumes (111.8 ng/g), and the lowest for cereals (27.8 ng/g). Considering the average daily individual consumption of these foods in Andalusia (southern Spain), the daily dietary intake of selenium supplied by this source is 15.36 micrograms/day for an adult. The content of total selenium in corn samples taken from the zone is independent of both human and industrial activities (P > 0.05).