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Chromium has been studied since the end of the 19th century, when carcinogenic effects of hexavalent Cr were discovered. Essentiality of trivalent Cr was demonstrated in 1959; Cr3+ has been studied in humans and laboratory animals since the 1970s and it is only since the 1990s that Cr has been studied as an essential element in livestock animals with the same intensity. Trivalent Cr is essential to normal carbohydrate, lipid and protein metabolism. It is biologically active as part of an oligopeptide - chromodulin - potentiating the effect of insulin by facilitating insulin binding to receptors at the cell surface. Cr absorption is low, ranging between 0.4 and 2.0% for inorganic compounds while the availability of organic Cr is more than 10 times higher. Absorbed Cr circulates in blood bound to the beta-globulin plasma fraction and is transported to tissues bound to transferrin. Absorbed Cr is excreted primarily in urine, by glomerular filtration; a small amount is excreted through perspiration, bile and in milk. This review describes Cr metabolism, the different biological functions of Cr and symptoms of Cr deficiency.

Buckwheat is introduced into the diet as an alternative crop of renewed interest due to its nutritive and health-promoting value. Experiments with animal models have demonstrated that buckwheat flour may alleviate diabetes, obesity, hypertension, and hypercholesterolemia. A number of nutraceutical compounds exist in buckwheat grains and other tissues. These are a rich source of starch, proteins, antioxidants, and dietary fibre as well as trace elements. The biological value (BV) of buckwheat proteins is comparable to BV of other protein sources. Besides high-quality proteins, buckwheat grains contain some components with prophylactic value: flavonoids, fagopyrins, or thiamin-binding proteins. For the food industry, buckwheat grains are a valuable raw material to be used for the production of functional foods. Buckwheat flour may be a valuable and important ingredient in diets or food products, taking into consideration its nutritive value and potential promotion of human health.

Coeliac disease is an autoimmune gluten-sensitive entheropathy. The only available treatment for it is the life-long adherence to a gluten-free diet although these products are often poor in proteins, minerals, and vitamins. The current study was designed to investigate the effect of buckwheat flour incorporation to a gluten-free experimental formulation on the size-related parameters, and microelements and proteins contents. Buckwheat flour affected positively the technological quality of bread, like bread specific volume index and loaf size. Increasing concentration of buckwheat flour (10-40%) in bread affected the proportional enrichment in proteins and microelements, especially in copper and manganese.

Four sequential extraction procedures (Sposito, Tessier, Silveira and Bureau Communautaire de Reference (BCR)) were used to evaluate the distribution of some metals (Fe, Cu, Cd and Zn) in a contaminated soil around a mining area. The results showed that Fe and Zn were mainly recovered in the recalcitrant soil fractions, while Cd was primarily localized in the exchangeable fraction. Soil Cu was highly associated with organic matter fraction. The amorphous Fe fraction in Silveira could be recognized as part of the Fe-Mn oxide fraction in Tessier and BCR procedures, while the crystalline Fe oxide fraction was classified into the residual fraction in Sposito, BCR and Tessier schemes. Although the same reagent was used to extract target fraction, less carbonate-bound Cu, Cu and Zn were extracted in Tessier procedure as compared to Silveira method, while Tessier scheme yielded a higher proportion of Fe, Cu and Zn in the Fe-Mn oxide fraction than BCR method. Due to the lack of uniformity of experimental conditions and the differences in extraction reagents, the extraction efficiency of metal species varied with the sequential extraction schemes. Therefore, care should be taken when comparing the results obtained by different sequential extraction procedures.

Although its demand increased greatly due to the volatile strong flavor and bioactive molecules, little information has been about the cultural characteristics of Tricholoma matsutake. In this study, we investigated the optimal medium composition of liquid culture with the goal of shortening the culture period, and to maximize polysaccharide production and mycelial growth. From these experiments we found that the optimal medium contained 40 g/L, glucose; 30 g/L, yeast extract; 1.5 g/L, KH₂PO₄; and 1 g/L MgSO₄ㆍ7H₂O. In flask culture, the maximum mycelial growth and polysaccharide production were 22.45 and 5.3 g/L, which were about 9 and 3 g/L higher than that at the basal medium, respectively.

The aim of the study was to evaluate cocoa beans quality produced in Cameroon, Ecuador, Nigeria and Ghana from safety position determining heavy and trace metals concentration and evaluating the oxidative stability of confectionery products prototypes (trials) with analysing cocoa beans. For evaluation of oxidative stability of confectionery products, the main ingredients - butter and cocoa beans kernels were tested making trials as milk chocolate prototype.The composition of confectionery ingredients affects quality of products; therefore it is very important to evaluate quality of raw materials in confectionery industry, as they are purchased practically in all regions of the world. Mercury, arsenic, lead, cadmium concentration was determined in whole cocoa beans as their presence in foods have toxic effect on human beings and their concentration are strictly limited as maximum residue limits for processing. Cocoa shells can be used as additive to confectionery products recipes therefore the object of the study was cocoa beans and cocoa shells.Analyzing cocoa beans quality indices there was established that lead, cadmium, aluminium and zinc concentrations vary in cocoa beans significantly. Differences in lead concentration in cocoa beans from Ghana, Cameroon and Ecuador were significant (p < 0.05) compared with concentration of lead in cocoa beans from Nigeria (p > 0.05). Cadmium concentration in cocoa beans from Cameroon was significantly different comparing with cocoa beans from Nigeria, Ecuador and Ghana (p > 0.05). Differences in aluminium concentration in cocoa beans kernels were significant (p < 0.05) in all analyzed samples. Concentration of zinc was higher in shells of cocoa beans, especially in shells of cocoa beans from Ecuador (p < 0.05). The presence of cocoa products in milk chocolate prototypes inhibited the speed of lipid peroxidation. The different trace and heavy metals concentrations in cocoa beans should be taken into account choosing ingredients and components for confectionary products production particularly those with high content of cocoa (chocolates, sweets, cocoa fillings, cocoa creams and others) with the aim to prevent oxidation process during shelf-life of products.

:  Trace element distribution patterns were examined in Japanese eel from five Asian regions for the purpose of identifying the elements and patterns that could be used to determine provenance. Distinctive patterns were found in eels from the Japanese prefectures of Miyazaki, Kagawa, and Shizuoka, and from Taiwan and China. The levels of six trace elements, selenium, mercury, copper, manganese, zinc, and arsenic, in muscle tissue varied among eels of different origins, and factorial analysis of the elemental patterns showed that Factor 1 was attributable to selenium and mercury levels and Factor 2 to zinc and copper levels. Multivariate analysis showed that the patterns of elemental composition in fish muscle were mainly differentiated by these two factors.

The inorganic element contents of trees were measured to evaluate the safety of using wood biomass as thermal power generation fuel. Twelve species of typical conifer trees and 17 species of typical broad-leaved trees in Japan plus 9 species of commonly imported trees were selected and analyzed for the main inorganic elements and several trace elements that are potentially harmful in combustion ash. The ash content in bark, especially in the inner bark, was higher than that in wood, but the highest concentration was in the leaves. In almost all parts of the trees, the order of inorganic element concentration was calcium = potassium = magnesium = sulfur = phosphorous. Among the trace elements, the boron content was high and the mercury content was recorded as being high in conifer bark.

The inhibitory effect of four trace elements on production of volatile fatty acids (VFA) and lactate was evaluated in cultures of rumen contents containing lead, mercury, cadmium and arsenic at 50, 100 and 250 microg/ml. The production of VFA in cultures containing Pb2+, Hg2+, Cd2+ and As5+ at 50 microg/ml was decreased by 15.9, 40.0, 29.1 and 35.6%, respectively. The effect of trace elements on molar profile of VFA was variable, which suggests a different toxic effect of elements tested on different groups of rumen microorganisms. Increasing concentrations of Pb2+ in rumen cultures decreased molar proportion of acetate and increased that of butyrate, whereas Hg2+ and Cd2+ increased molar percentages of acetate and decreased butyrate. Lactate concentration in cultures containing Hg2+ increased in a dose-dependent manner from 3.10 to 9.20 microM/ml. Effects of other trace elements on lactate production were not consistent.

Upju un ezeru piesārņojums ir uzskatāms par vienu no nozīmīgākajām vides problēmām. Biogēno elementu un toksisko mikroelementu uzkrāšanās nogulumos atspoguļo piesārņojumu sateces baseinā, bet piesārņojošo vielu akumulācijas analīze nogulumu profilos ļauj izsekot cilvēku ietekmes mainībai reģionā. Tomēr, tā kā piesārņojošās vielas ir saistītas ar citām vielām nogulumos, svarīgi ir analizēt ne tikai vielu kopējās koncentrācijas, bet arī to atrašanās formas. Šī pētījuma mērķis ir analizēt fosfora un mikroelementu koncentrācijas un fosfora savienojumu atrašanās formu mainību Engures ezera nogulumu profilos un noteikt antropogēno ietekmju raksturu uz organisko vielu uzkrāšanos un nogulumu īpašībām. Pētīto elementu koncentrācijas Engures ezera nogulumos ir fona koncentrāciju līmenī, īpaši, ja salīdzina ar koncentrācijām Rietumeiropas valstu ūdenstilpju nogulumos. Tomēr elementu koncentrāciju analīze nogulumu profilos ļauj izsekot antropogēnās slodzes intensitātes mainībai pēdējo 100 gadu laikā un pamatot nepieciešamās rīcības ezera ilgtspējīgas apsaimniekošanas risinājumu nodrošināšanai. Biogēno elementu koncentrācijas noteikšana ezera nogulumos ļauj noteikt to fona koncentrāciju līmeņu ezeru kopšanas pasākumu īstenošanai. Environmental pollution of lakes and rivers is considered as one of the most important environmental problems. Analysis of nutrient and trace element accumulation in sedimentary phases of lakes can reflect the overall regional pollution level, and the observed accumulation patterns of pollutants in sediment profiles can be used to reconstruct the history of anthropogenic impacts. As pollutants in sediments are associated with other substances, it is important not only to study total concentrations of pollutants, but also their speciation forms. The aim of this study was to describe phosphorus (including speciation forms) and trace element concentrations in sediment profiles of Lake Engure and to evaluate human impact on organic matter accumulation and properties in lake sediments. The concentrations of the studied elements in sediments of Lake Engure are at background levels, which is clearly evident when compared with metal concentrations in lake sediments in West European countries. The analysis of element concentration changes in sedimentary profiles provided information about trends in recent accumulation (within the last 100 years) and on the balance between natural and human-induced accumulation processes. Analysis of nutrient concentrations in sediments aided in identifying background values as targets for lake management activities.