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Leek (Allium porrum L.), a commonly grown vegetable widely used in the food industry, has gained increased interest in recent years in connection with its content of bioactive substances. Therefore, this study aimed to determine and evaluate the influence of cultivar and morphological part on the total content of polyphenols, sulfur compounds, and the antioxidant activity in the monitored morphological parts of leek (Allium porrum L.). The total polyphenol content (TPC) in the white part of analyzed leek cultivars ranged from 446.30 to 1580.55 mg GAE.kg-1 DM. TPC in the green part of analyzed leek cultivars ranged from 748.09 to 2172.78 mg GAE.kg-1 DM. TPC in the leaves of analyzed leek cultivars ranged from 2301.24 to 5477.73 mg GAE.kg-1 DM. The antioxidant activity (AA) in the white part of analyzed leek cultivars ranged from 3.70 to 14.23 mmol TE.kg-1 DM. AA in the green part of analyzed leek cultivars ranged from 6.89 to 14.38 mmol TE.kg-1 DM. AA in leaves of analyzed leek cultivars ranged from 30.85 to 106.92 mmol TE.kg-1 DM. The total sulfur content (TSC) in the white part of analyzed leek cultivars ranged from 0.25 to 0.52 %. TSC in the green part of analyzed leek cultivars ranged from 0.27 to 0.52 %. TSC in the leaves of analyzed leek cultivars ranged from 0.31 to 0.59 %. Based on the analysis of variance, we can state that statistically higher (p< 0.05) TPC, AA, and TSC were determined in the leaves of the leek. Statistically higher (p< 0.05) TPC, AA, and TSC in all morphological parts were determined in the cultivar De Carentan. The results confirmed the variability of bioactive substances and antioxidant activity in the individual monitored cultivars, but also in the monitored morphological parts of the leek. [ABSTRACT FROM AUTHOR]

Sweet chestnuts are highly regarded and widely consumed throughout Europe because of their nutritional composition and health benefits, which have become important in the human diet, for example, in gluten-free diets. This study aims to assess the impact of heat treatment using the UV-VIS spectrophotometry methods. TPC values (mg GAE/g DW - dried weight) ranged from 1.935 to 6.165 (raw flesh), 1.676 to 4.342 (boiled samples), 1.580 to 3.091 (roasted samples), 1.193 to 8.272 (microwaved samples), and 2.556 to 5.655 (steamed samples). The DPPH values (μmol TE/g DW) for raw flesh ranged from 4.232 to 5.094, for boiled samples from 3.396 to 5.147, for roasted samples from 3.185 to 4.726, for microwaved samples from 2.798 to 5.816, and for steamed samples from 4.441 to 5.171. The FRAP antioxidant activity (μmol TE/g DW) values ranged from 10.971 to 207.11 (raw flesh), 4.058 to 134.651 (boiled samples), 11.954 to 132.476 (roasted samples), 7.795 to 179.129 (microwaved samples), and 17.468 to 367.957 (steamed samples). Among the methods used, steaming and microwaving had the greatest impact on total polyphenol content and antioxidant activity (DPPH, FRAP). [ABSTRACT FROM AUTHOR]

The Jerusalem artichoke (Helianthus tuberosus L.) is high in protein, inulin, and other bioactive ingredients. In this study, the effect of heat treatment methods as well as the effect of the variety on its total polyphenol content and antioxidant activity were investigated. The total polyphenol content ranged from 0.36 to 0.87 mg GAE.g-1 DW in raw flesh and from 0.41 (baking) to 1.01 mg GAE.g-1 DW (boiling) in heat-treated tubers. The antioxidant activity (AA) was determined by the methods of DPPH and FRAP. DPPH values ranged from 0.18 to 1.09 (raw flesh), 3.03 to 4.74 (boiled samples), 2.34 to 2.94 (baked samples), 2.88 to 3.22 (microwaved samples), and 2.25 to 6.17 (steamed samples) μmol TE.g-1 DW. AA values by the method FRAP ranged from 3.5 to 3.82 (raw flesh), 7.51 to 8.53 (boiled samples), 4.26 to 6.80 (baked samples), 4.98 to 6.72 (microwaved samples), and 4.89 to 8.04 (steamed samples) μmol TE.g-1 DW. All studied heat treatment methods had a positive effect on the TPC and AA. Our results confirm the promising potential of artichoke use in functional food preparation. [ABSTRACT FROM AUTHOR]

The Horehronie region belongs to the oldest industrial areas in Slovakia. It is contaminated by residual acid tar dumps from times of Petrochema Dubová factory production since 1964. In the presented study, heavy metals (Cu, Cd, Ni, Zn, Pb) were determined in soils and forest fruits (Vaccinium myrtillus L., Vaccinium vitis-idaea L., Fragaria vesca L., Rosa canina L., Rubus idaeus L.) collected over two years from five locations in the Horehronie using Flame AAS method (Zn, Cu, Ni) and Graphite Furnace AAS method (Cd, Pb). The cadmium content, which was higher than its limit value in all analysed soils, poses the biggest threat. We determined more than 20 times the limit value for cadmium in the sample Veľká Smrekovica (9.17 mg/kg). The contamination factor (Cf) values and the geoaccumulation index (Igeo) indicate that this hazardous metal is involved in soil contamination to a large extent. The highest values of the degree of contamination (Cdeg) and the pollution load index (PLI) were determined in samples from the Ždiarska dolina and the Veľká Smrekovica. The contents of nickel and zinc were higher than the limit values only in the 1st sampling year in the Ždiarska dolina sample (46.30 mg/kg; 138.30 mg/kg). The results showed that soil monitoring and remediation of old environmental burdens are important in the territory of the Horehronie region. The highest permissible amounts for cadmium were exceeded in all types of forest fruits (0.03-0.18 mg/kg FW). The contents of nickel and lead were exceeded only in the sample of rosehips (Rosa canina). The contents of zinc and copper were lower than the permissible amounts in all samples. The estimated daily intake (EDI) was lower than the acceptable daily intake of all heavy metals. The bioaccumulation factor (BAF), total hazardous quotient and hazard index of the analysed samples was < 1, which means that the consumption of forest fruits from the Horehronie does not pose a health risk for the consumer. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.), is used as both a food and traditional medicine for several illnesses throughout the world. 7 garlic cultivars (Novozamocky, Lumir, Mojmir, Havran, Garpel, Eden Rose, and Bjetin) were analyzed in this study. Since modern consumer demands encourage the consumption of foods with positive effects on human health, research into the nutritional properties and chemical composition of traditional crops, like garlic, is important. Knowledge of these properties could support the cultivation of cultivars with the highest content of bioactive compounds. Total polyphenol content (TPC) determined by Folin - Ciocalteau method ranged from 797.11 to 1183.98 mg GAE.kg-1 DM. Total flavonoid content (TFC) determined by the aluminum chloride method ranged from 15.96 to 28.18 mg CE.kg-1 DM. Antioxidant activity (AA) determined by the ABTS method ranged from 1.97 to 4.42 mmol TE.kg-1 DM. Antioxidant activity (AA) determined by the FRAP method ranged from 1.12 to 2.64 mmol TE.kg-1 DM. Statistical evaluation of results showed a difference between garlic cultivars. The highest antioxidant activity and the highest content of bioactive substances were determined in the cultivar Garpel. High positive correlations (p < 0.001) were determined between TPC and TFC (r = 0.746), TPC and AA ABTS (r = 0.862), TPC and AA FRAP (r = 0.922), TFC and AA ABTS (r = 0.792), TFC and AA FRAP (r = 0.808), and AA ABTS and AA FRAP (r = 0.896). Garlic is confirmed to be a natural source of antioxidants, polyphenols, and flavonoids. [ABSTRACT FROM AUTHOR]