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In the three-year field trials (2009-2011) at two locations with different altitudes a total of 14 potato cultivars with different colour of flesh (yellow, white, red and purple) were grown. The content of total glycoalkaloids (TGA) was determined by HPLC. TGA content ranged from 18.8 to 102.4 mg/kg fresh matter and none of the cultivars reached the value of risk to human health. Conclusive and decisive influence on the content of the TGA was recorded in genotype. Individual cultivars reached 0.47 to 1.45 of the TGA content in the control cv. Agria. In terms of the colour of the flesh the highest TGA content was found in group of red-fleshed cultivars (1.53 × higher than the average of cultivars with yellow or white flesh); while red-fleshed cv. Rote Emma reached the absolutely lowest TGA content of 14 cultivars, which confirms the decisive role of genotype. On warm, dry habitats in the lowlands a higher TGA content was observed when compared with the amount raised in a typical potato field.

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 content 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.

Einkorn (Triticum monococcum L., subsp. monococcum), emmer (Triticum dicoccum Schuebl [Schrank], subsp. dicoccum) and spring wheat (Triticum aestivum L.) may be rich in hydrophilic antioxidants, therefore being a potential food source with high nutritional properties. The aim of the present study was to assess the content of free ferulic acid (FFA) and total polyphenols (TP) beneficial for human health in wheat varieties and accessions for breeding and production. Einkorn, emmer and spring wheat varieties were assessed for TP and FFA contents in the precise two-year field experiments. The highest FFA content was determined in emmer wheat varieties and spring cv. Granny. High TP content was characteristic for emmer and spring wheat accessions, however also some einkorn ones were characterised by high levels. Year of cultivation showed a significant impact on FFA contents.

The aim of this study was to determine that the total anthocyanin content (TAC) and antioxidant activity (AOA) in potato flesh with different colours grown in the Czech Republic. Four yellow- or white-, six purple- and four red-fleshed varieties were grown in 2009 at two different sites (Valečov - highland, seed potato area at 460 m a.s.l., Přerov nad Labem - lowland, new potatoes area at 178 m a.s.l.) in precise field trials. For purple- and red-fleshed varieties, average TAC values ranged from 61.5 to 573.5 cyanidin mg/kg of FM and significant effect of the variety of the TAC was found. High content reached the Violette and Vitelotte varieties with dark purple flesh, and the lowest content the Blue Congo variety with light purple marbled flesh. Significantly higher TAC was found in a lowland area Přerov nad Labem, which is probably related to drought stress. The lowest AOA was achieved by a group of varieties with yellow or white flesh - averaging 82.8 mg ascorbic acid equivalent/kg FM, in a group of red-fleshed varieties it was higher 4.34 times and in a group of purple-fleshed varieties even 5.03 times higher. Also between purple-and red-fleshed varieties significant differences in AOA were found, both high and low values of AOA showed the same varieties as in the case of the TAC. Among experimental sites higher AOA was also demonstrated at Přerov nad Labem. Correlation analysis showed a strong correlation between AOA and TAC (r = 0.8099).

Opium poppy (Papaver somniferum L.) is currently an important agricultural commodity, with the product being used in the food industry (seed) as well as in the pharmaceutical industry (morphine and other alkaloids). Intensive production of poppy leads to a specific direction of breeding with the aim to obtain highly productive cultivars of the so-called food industry or industrial type. The paper evaluates 57 genetic resources (mostly cultivars), comparing the groups of values representing the indicators of production-significant morphologic and agricultural characters (capsule size; morphine content in poppy straw; weight of dry, empty capsule) and content of morphine in the poppy straw, in relation to the ideotype of poppy, which in these indicators represents 100% of the value. On average lower values in the above indicators were achieved by cultivars with white-coloured seed, including morphine content; concrete data are specified in three cultivars with morphine content in the poppy straw above 0.40%. In blue-seed to grey-seed cultivars, except for the high-morphine cultivar Buddha (1.85% of morphine), we found only six materials with a minimum morphine content of 0.8% in the poppy straw (maximum of 0.92%). These genetic resources also achieved very good values in the morphological indicator and average value in the economic indicator. The results will be used in the selection and classification of suitable genetic resources of poppy in breeding of industrial forms.

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 2004-2008 in the Czech Republic the effect of conditions of location, variety and mineral fertilization on ascorbic acid content (AA) in potatoes with different tuber flesh color was investigated. Significant was the effect of variety. The Marabel variety with the highest AA content (248 mg/kg FW) exceeded other eight varieties by 13.4-74.1%. The Valfi variety, in five-year trials the only variety with purple colored flesh, ranked among analyzed varieties moderately below average. In addition, in the year 2008 the group of seven varieties with purple and red tubers was evaluated and AA content lower by 15.2% compared to the group of varieties with yellow flesh was determined. Also, significant differences were determined between the varieties with coloured tubers; the highest AA content was found in the red-fleshed variety Highland Burgundy Red (234 mg/kg FW). A negative effect on AA content in tubers was observed at increased intensity of N fertilization (at 180 kg N/ha, AA decreased by 12.4% compared to 100 kg N/ha). Enhanced levels of potassium and magnesium fertilization had no effect on the AA content. The effect of location on AA content was not shown; however, from the four locations in average of five years a pronounced trend of the highest content of ascorbic acid on the location Přerov nad Labem with the highest temperature averages during vegetation period of experimental years was determined (by 0.9°C, 2.3°C, and 5.9°C higher compared with other locations).

Coloured potatoes Solanum tuberosum L.) were evaluated as important source of natural antioxidants. Eight varieties of these potatoes (Salad Blue, Shetland Black, Blue Congo, Blaue St. Galler, Highland Burgundy Red, Violette, Valfi, Vitelotte) grown in four different locations in the Czech Republic (Přerov nad Labem, Suchdol, Valečov and Stachy) were analysed. Content of majority antioxidants (anthocyanins, chlorogenic acid and ascorbic acid) was determined and the obtained results were correlated with antioxidant activity. Total anthocyanin content and antioxidant activity were determined spectrophotometrically and phenolic acids by HPLC-DAD. The best positive correlation was observed between total anthocyanin content and antioxidant activity (R2 = 0.64). Good correlation was found between chlorogenic acid content and antioxidant activity (R2 = 0.55); however, no correlation between ascorbic acid content and antioxidant activity (R2 = 0.08) was found.

Two isomeric series of new thieno-fused 7-deazapurine ribonucleosides (derived from 4-substituted thieno[2',3':4,5]pyrrolo[2,3-d]pyrimidines and thieno[3',2':4,5]pyrrolo[2,3-d]pyrimidines) were synthesized by a sequence involving Negishi coupling of 4,6-dichloropyrimidine with iodothiophenes, nucleophilic azidation, and cyclization of tetrazolopyrimidines, followed by glycosylation and cross-couplings or nucleophilic substitutions at position 4. Most nucleosides (from both isomeric series) exerted low micromolar or submicromolar in vitro cytostatic activities against a broad panel of cancer and leukemia cell lines and some antiviral activity against HCV. The most active were the 6-methoxy, 6-methylsulfanyl, and 6-methyl derivatives, which were highly active to cancer cells and less toxic or nontoxic to fibroblasts.

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., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

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)., (Copyright © 2010 Elsevier B.V. All rights reserved.)