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The content of hippuric acid in raw goat's and sheep's milk and the content of benzoic acid in model fermented milk drinks prepared using different cultures of bacteria of milk fermentation were determined. All fermented milk drinks contained benzoic acid in the range 5.0-78 mg kg-1. Higher quantity of benzoic acid in fermented sheep's milk drinks corresponded also to significantly higher quantity of hippuric acid in raw sheep's milk. No significant differences among used cultures of bacteria of dairy fermentation and the quantity of benzoic acid in fermented milk drinks were recorded. In addition, the quantity of benzoic acid in various commercial goat's and sheep's cheeses produced directly in farms was analyzed. The contents of benzoic acid in cheeses ranged from 5.1 to 90 mg kg-1. No significant difference in the quantity of benzoic acid from goat's and sheep's cheeses was found, whereas significant differences were registered in the quantity of benzoic acid in cheeses produced in individual farms.

The genus Stellaria (Caryophyllaceae) presents widely distributed plants often used in traditional medicine. Flavonoids are highly active plant secondary metabolites that may be involved in some of the effects of Stellaria plants. In this study, two new high-performance liquid chromatography–electrospray ionization tandem mass spectrometry (HPLC–ESI-MS-MS) methods were developed for the determination of flavonoids and isoflavonoids in plant material. The separations were performed on a reverse-phase C18 column with gradient elution using methanol and water with 0.5% acetic acid as the mobile phase. Multiple reaction monitoring was used for the tandem mass spectrometry detection and the two most intensive transitions were chosen for the identification of each analyte. The limits of detection and the limits of quantification were between 0.2 and 15.0 ng/mL and 0.6 and 50.0 ng/mL. The developed methods were successfully used for the analyses of four representatives of the genus Stellaria. All the studied her...

A B S T R A C T The objective of this two-year study was to determine the main carotenoids in 15 varieties of potatoes (Solanum tuberosum L.) with different flesh colour – white, yellow, red and purple and two varieties of Solanum phureja. Content of total anthocyanins in pigmented potatoes was also determined and compared with the carotenoid level. Potatoes were cultivated in two localities with different soilclimatic conditions. Content of carotenoids and anthocyanins was affected by variety and locality. Moreover, carotenoid content was influenced by the growing year. Content of total carotenoids ranged from 0.779 to 13.3 mg/kg dry matter (DM). The main carotenoid was lutein in all varieties (54–93%) furthermore violaxanthin, neoxanthin, zeaxanthin and b-carotene were identified in most of the analysed samples. The highest carotenoid content was found in S. phureja varieties. The pigmented varieties Blaue Anneliese, Violetta, Olivia (all purple) and H.B. Red (red) showed comparable carotenoid level with the yellow-fleshed variety Agria; other pigmented varieties contained similar carotenoid levels as white-fleshed varieties. Content of total anthocyanins ranged from 210 to 2419 mg/kg DM and correspond to flesh colour intensity. A weak correlation between carotenoids and anthocyanins was found (r 2 = 0.33). Thus some coloured varieties could be a good source of both studied phytochemicals.

Seeds of twelve white and red vine varieties cultivated on six vine-growing areas were assessed as a by-product after winemaking on the contents of total polyphenols (TP) and phosphorus (P) spectrophotometrically, total tocols (TC) by HPLC-FLD, and metals (Ca, Mg, Na, K, Fe, Zn, Cu and Mn) by FAAS. Remaining TP and TC levels were mainly affected by the variety, while levels of microelements (Cu, Mn and Zn) and P or K by the vine-growing area. The highest TC levels were found in the seeds of the Muller Thurgau, Pinot Noir and Zweigeltrebe varieties. Different white and red winemaking methods have significant impact on the TP content with higher remaining levels in white varieties. Conversely, red varieties contained higher levels of macroelements except P, however no significant differences between varieties have been found. Red varieties contained higher Fe, Cu, Zn and comparable Mn levels. Results herein revealed the considerable potential of grape seeds, a by-product of the vinification process, as a valuable inexpensive source of high added value of nutritionally beneficial compounds – polyphenol and tocol antioxidants and macro- and microelements for use as feed additives in animal nutrition.

Einkorn (Triticum monococcum L., subsp. monococcum), emmer (Triticum dicoccum Schuebl [Schrank], subsp. dicoccum) and spring bread wheat (Triticum aestivum L.) may be rich in lipophilic antioxidants (tocols and carotenoids), and therefore potential food sources with good nutritional properties. The aim of the present study was to determine the contents of major lipophilic antioxidants beneficial for human health in wheat varieties and landraces for breeding and production. In field experiments over two years, fifteen einkorn, emmer and spring wheat varieties were analysed for the contents of tocols and carotenoids in grain. A high carotenoid content (lutein, zeaxanthin, β-carotene) was typical for the selected einkorn genotypes. Among the analysed wheat species, the highest content was of β-tocotrienol, especially in the einkorn accessions. α-Tocotrienol was abundant in einkorn and emmer wheat species. Higher contents of α- and β-tocopherols were characteristic of spring and emmer wheats. δ-Tocotrienol has been detected for the first time in einkorn and some emmer accessions, although in low concentrations. Significant effects of genotype on the contents of carotenoids and tocols were found with einkorn differing from emmer and spring wheats. The year of cultivation had less effect on the contents of carotenoids and tocols. Selected accessions of einkorn with high contents of carotenoids and tocotrienols as well as spring and emmer wheats with higher contents of tocopherols are good sources of antioxidants with potential health promoting benefits for the production of nutritionally enhanced foods.

The impact of selected factors – cultivar, storage, cooking and baking on the content of total anthocyanins (TAC) in coloured-flesh potato cultivars has been studied. TAC ranged from 248.5 to 2257.8 mg kg −1 dry matter (DM). TAC difference between cultivars was statistically significant. Cold storage (4 °C) influenced TAC differentially. In the Violette and Highland Burgundy Red cultivars TAC increased by 18.5% and 12.1% respectively, and in the Valfi cultivar it decreased by 33.9%. Baking increased TAC 3.34 times whereas cooking in boiled water increased it 4.22 times. Correlation between antioxidant activity (AOA) and TAC ( r 2 = 0.659) has been found. The Violette, Vitelotte and Highland Burgundy Red cultivars with the highest TAC showed high AOA and the Shetland Black cultivar and the cultivars Salad Blue and Blue Congo with a “marbled” texture showed the lowest TAC and AOA. Individual anthocyanidins are fingerprints of colour-fleshed potato cultivars.

Major antioxidants and antioxidant activity in eight varieties of tomatoes were determined. Hydrophilic and lipophilic antioxidant activity (HAA and LAA) was determined by the ABTS assay and ascorbic acid and carotenoid contents were determined by HPLC-DAD. The HAA has far more significant impact on total antioxidant activity (83%) as compared with LAA. HAA was increasing during all ripening stages and was strongly correlated with ascorbic acid content ( r = 0.83). During the ripening the LAA was increasing till the III. stage of maturity and then decreased. The main carotenoids determined in the red-fruit tomatoes were lycopene, β-carotene and lutein. The content of lycopene has been increasing equally during the ripening. β-Carotene and lutein were intensively synthesized between the I. and II. stage of maturity. Among ascorbic acid, α-tocopherol, lycopene, β-carotene and lutein standards ascorbic acid was determined as the most efficient antioxidant followed by α-tocopherol and β-carotene. Antioxidant activity of ascorbic acid, α-tocopherol, β-carotene and lutein grew equally with increasing concentration, however lycopene was the most effective in its lowest concentration. The analysis of two-component mixtures showed significant synergism between lycopene-lutein, lycopene-β-carotene and α-tocopherol-β-carotene.

Wheat contributes significantly worldwide to antioxidant income with beneficial healthy effects. Two varieties of einkorn wheat (Triticum monococcum L. – Escana and Schwedisches Einkorn), two varieties of wild emmer [Triticum dicoccum Schuebl (Schrank)] (Rudico and Kahler Emmer) and three varieties of spring wheat (Triticum aestivum L. – Granny, Kartner Fruher and SW Kadrilj) were evaluated for tocols – tocopherols and tocotrienols by high performance liquid chromatography – electrospray ionisation tandem mass spectrometry (HPLC–ESI/MS/MS). Investigated emmer and einkorn wheat varieties have shown minor lower total tocols content in comparison with spring varieties, however significant typical levels of tocopherols and tocotrienols were found in these groups. In einkorn wheat varieties the major abundance of total tocols is represented by tocotrienols (Schwedisches Einkorn 65.0%, Escana 54.9%), in emmer wheat varieties the abundance of tocotrienols and tocopherols were similar (Rudico 48.9% of tocotrienols, Kahler Emmer 47.6%), whereas in spring bread wheat higher tocopherols (SW Kadrilj 54.5%, Kartner Fruher 60.2%, Granny 55.0%) were recorded.

The impact of peeling and three cooking treatments (boiling, baking and microwaving) on the content of selected phytochemicals in white-, yellow-, red- and purple-fleshed potatoes was investigated. Ascorbic acid and chlorogenic acid contents were determined by HPLC-DAD, total anthocyanin content by pH-differential spectrophotometry, glycoalkaloid, α-chaconine and α-solanine contents by HPLC-ESI/MS/MS. All cooking treatments reduced ascorbic and chlorogenic acid contents, total glycoalkaloids, α-chaconine and α-solanine with the exception of total anthocyanins. The losses of ascorbic and chlorogenic acids were minimised with boiling and total anthocyanin levels retained the highest. Boiling of peeled tubers decreased contents of total glycoalkaloids (α-chaconine and α-solanine) and appeared as the most favourable among the three tested methods. Moreover, due to higher initial levels, red- and purple-fleshed cultivars retained higher amounts of antioxidants (ascorbic acid, chlorogenic acid and total anthocyanin) after boiling and may be healthier as compared with white or yellow cultivars.

Study was focused on the evaluation of pesticide adsorption in soils, as one of the parameters, which are necessary to know when assessing possible groundwater contamination caused by pesticides commonly used in agriculture. Batch sorption tests were performed for 11 selected pesticides and 13 representative soils. The Freundlich equations were used to describe adsorption isotherms. Multiple-linear regressions were used to predict the Freundlich adsorption coefficients from measured soil properties. Resulting functions and a soil map of the Czech Republic were used to generate maps of the coefficient distribution. The multiple linear regressions showed that the K(F) coefficient depended on: (a) combination of OM (organic matter content), pH(KCl) and CEC (cation exchange capacity), or OM, SCS (sorption complex saturation) and salinity (terbuthylazine), (b) combination of OM and pH(KCl), or OM, SCS and salinity (prometryne), (c) combination of OM and pH(KCl), or OM and ρ(z) (metribuzin), (d) combination of OM, CEC and clay content, or clay content, CEC and salinity (hexazinone), (e) combination of OM and pH(KCl), or OM and SCS (metolachlor), (f) OM or combination of OM and CaCO(3) (chlorotoluron), (g) OM (azoxystrobin), (h) combination of OM and pH(KCl) (trifluralin), (i) combination of OM and clay content (fipronil), (j) combination of OM and pH(KCl), or OM, pH(KCl) and CaCO(3) (thiacloprid), (k) combination of OM, pH(KCl) and CEC, or sand content, pH(KCl) and salinity (chlormequat chloride).

In precise field trials in the Czech Republic from 2004–2008 the impact of location conditions, varieties with yellow, purple and red flesh and mineral fertilization on the content of total polyphenols (TP) and chlorogenic acid was investigated. The highest TP contents were reported at two locations with extreme climatic conditions; in those under stress due to low temperatures in the vegetation period at the mountainous area Stachy (5.89 mg TP/g DM) and those under drought stress in the warm lowland location Přerov nad Labem with light sandy soil (5.81 mg TP/g DM). The five-year experiment with the purple-fleshed Valfi variety (13.29 mg TP/g DM) reached 2.46 to 3.18 times higher content of TP in comparison with eight yellow-fleshed varieties. The yellow-fleshed Karin variety (5.39 mg TP/g DM) outperformed TP content of other yellow-fleshed varieties by 3.1 to 29.1%. In another experiment conclusive differences between the eight varieties with purple and red flesh were found; the highest TP content was detected in cv. Violette (25.9 mg TP/g DM) with the darkest purple flesh. As to the chlorogenic acid content similar relationships between varieties were found as in the case of TP. High linear correlation (r = 0.8536) was found between the content of chlorogenic acid and the content of TP. Among the treatments of mineral N, P, K and Mg fertilization, the content of TP was only affected by a treatment with a higher dose of K and Mg, causing a decrease in TP content.

In precise field trials in the years 2010 and 2011 the effect of genotype and location in cultivars with yellow, white, purple or red flesh on the content of chlorogenic acid (CA) and in 2011 and 2012 the effect of organic cultivation were evaluated. The results show a statistically significant effect of genotype to CA content, which ranged from 74.0 mg/kg fresh matter (FM) (Agria) to 825 mg/kg FM (Vitelotte). Demonstrable effect of flesh colour on CA con tent between cultivars with coloured flesh was found (430 mg/kg FM) in comparison with cultivars with yellow or white flesh (71.1 mg/kg FM). For cultivars with coloured flesh rather the genotype specific cultivar ruled than the purple or red flesh colour. In terms of the influence of location, higher CA levels were found on warm locations with frequent periods of drought in comparison with locations of high altitude climatic conditions which are favourable for potato cultivation. In the organically grown potatoes significantly higher levels of CA were found as compared with conventional treatment.