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Elemental content of propolis samples from Pest, Zala and Bács-Kiskun county (Hungary)
149-153Views:235The elemental content of 61 raw propolis samples from Pest, Zala and Bács-Kiskun county (Hungary) were analyzed by ICP-OES. The content of Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr and Zn were measured in the samples. Median is higher than mean in all cases based on the summarized results. It can be explained by the outliers, moreover it has a non-normal distribution. The concentrations are in an extremely wide range, the ratio of the maximum and minimum is under 10 in case of six elements, between 10 and 35.1 in the case of other six elements,and more than 300 in case of Zn. Significant differences are between counties only in the case of B, K and P based on ANOVA. Other elements have no significant differences. The following order can be set up based on the mean concentrations and the wide ranges: K≥Ca>P≥S≥Fe≥Mg≥Al>Zn≥Na>Mn≥B>Cu≥Sr. Moreover it can be established, that the measured concentrations are near the same or in some cases lower than in other publications.
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Element content analyses in the Institute for Food Sciences, Quality Assurance and Microbiology
203-207Views:122The role of chemical elements to ensure and promote our health is undisputed. Some of them are essential for plants, animals and human, others can cause diseases. The major source of mineral constituents is food, drinking water has a minor contribution to it, so the knowledge of elemental intake through food is crucial and needs continuous monitoring and by this way it promotes the food quality assurance and dietetics.
With the evolution of spectroscopic methods increasingly lower concentrations could be determined, so the elemental composition of a sample could be more precisely and fully described. Due to the results the gathered knowledge up to the present is supported and new observations can be done helping us to understand such complex systems as biological organisms are.
The quality of a food is determined by the full process of its production, consequently it starts with agricultural production so elemental-analysis usually cover the whole soil – plant – (animal) – food chain, by this way the „Fork-to-Farm” precept is true in elemental analysis field also.
The history of elemental analysis in the University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Food Processing, Quality Assurance and Microbiology goes back to 1980s when the so called Regional Measurement Central gave the background for research. The continuous deployment resulted in an obtain of an inductively coupled plasma atomic emission spectrometer (ICP-AES) in 1988, which extended the scope of examinations due to its excellent performance characteristics
compared to flame atom absorption (FAAS) and flame emission spectrometers (FES). The instrumental park retain up to date correlate to the developing analytical techniques due to acquiring a newer ICPAES in 1998 and an inductively coupled plasma mass spectrometer in 2004 – which sensitivity is three order of magnitude better compared to ICP-AES. The Institute supports the work with its own ICP-AES and ICP-MS since 2011. -
Element Content of Herbaceous Plants in the Floodplain Meadows
55-58Views:111Animals require well-balanced nutrition. The elemental content of the vegetation of meadows is influenced by as many factors such as heat, rainfall, irrigation, soil type and nutrients, meadow types, species, aspects of the vegetation period and cultivation.
Natural meadows used extensively are common sights on river floodplains. Since chemicals are banned and the species number is high, measuring the elemental composition of plants on these meadows is beneficial. Cenological survey and element content measurements were held on the rich flora of four natural meadows in the year 2001.
Weeds, in a wider sense, are plants not directly involved in growing, although their nutritional values make them important costituents of feed. Meadows are enriched by their relatively high microelement content.
On the sampling sites, the ratio deviated from the ideal 2/3 parts monocotyledon and 1/3 part dicotyledon, but this did not mean a Mn deficiency as it would have been assumed. -
Investigating the above-ground biomass values of sweet potatoes (Ipomoea batatas)
35-39Views:122The role of sweet potato tubers in human nutrition is not new. The above-ground biomass of sweet potatoes is not used for nutritional purposes in most countries, but it has a high biological value. Therefore, the aim of the present study is to investigate the production of press fibre from above ground biomass by wet fractionation. Two sweet potato varieties (purple- and white-fleshed sweet potato) and two types of irrigation system were used: bubbling water flow system (BWS) and continuous water flow system (CWS). Glucan, xylan, arabinan were analysed by HPLC and elemental content was measured by ICP-OES. Our results show that the total carbohydrate content in the pressed fibre of the leaf blades (27.64–29.88 %w/w) is lower than in the stem with petiole (51.14–57.36 %w/w). No significant difference in glucan, xylan and arabinan content was observed in the leaf blade. In the stem with petiole, significant differences were observed for xylan and arabinan contents. For elemental content, generally higher values were measured in the leaf blade than in the stem with petiole. This information may be relevant for the selection of the appropriate variety and treatment, even for the production of functional food.
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Toxic elemental content of Hungarian blaufränkisch wines
87-90Views:165Toxic elemental contents are one of the food safety risks in wines. Therefore International Organization of Vine and Wine (O.I.V.) defined the limit of some elements in it. Thirty Hungarian blaufränkisch wines were analysed by ICP-MS in order to determine the concentration of toxic elements. All wines are passed by the O.I.V limits to toxic element content (Cu, Zn, Cd, Pb) according to analysis. Copper is the only outlier in some samples, but they also did not overstep the limit. In the case of zinc the maximum is approximately fourth, in case of cadmium and lead the highest concentration is less than tenth and sixth of the O.I.V. limit, respectively.
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The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
163-168Views:246The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol and the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.
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The effect of copper fungicides on the rate of photosynthesis and the transpiration of hop plants
117-123Views:91The paper evaluates the effect of copper fungicide spraying on the rate of photosynthesis and transpiration of hops, the influence of spraying on the elemental copper content in the leaves and cones hop variety Agnus. Photosynthetic rate was measured by LC pro+ (infrared analyzer) in the Hop Research Institute Saaz in the field in some periods of 2008, 2009 and 2010. Dry cones and leaf samples (taken before and after application of copper fungicides) were analyzed in an accredited laboratory for elemental copper.