This study aimed to evaluate the mineral content, and content of bioactive compounds in fruits of Cornelian cherry (Cornus mas L.). Neochlorogenic acid, chlorogenic acid, caffeic acid, and rutin were determined in the samples. Vitamin C content ranged from 610.36 to 1344 mg kg⁻¹ FW. Content of K, Ca, P, Mg, and Na in samples ranged from 1750.8 to 2645.7 mg kg⁻¹ FW, from 281.14 to 561.62 mg kg⁻¹ FW, from 180.38 to 294.95 mg kg⁻¹ FW, from 68.19 to 115.43 mg kg⁻¹ FW, and from 2.48 to 71.33 mg kg⁻¹ FW respectively. Content of Fe, Zn, Cu, Mn, Ni, Cr, and Co in samples ranged from 2.77 to 4.88 mg kg⁻¹ FW, from 0.49 to 0.99 mg kg⁻¹ FW, from 0.25 to 0.53 mg kg⁻¹ FW, from 0.07 to 0.17 mg kg⁻¹ FW, from 0.02 to 0.13 mg kg⁻¹ FW, from 0.01 to 0.02 mg kg⁻¹ FW, and from 0.01 to 0.08 mg kg⁻¹ FW respectively. Variations across cultivars were found to be statistically significant, indicating that genetics is a key factor influencing the concentration of bioactive compounds and minerals in Cornelian cherry fruits. Understanding the genetic factors influencing mineral and bioactive compound content in cornelian cherry cultivars is essential for targeted breeding programs, crop improvement, and the development of cultivars with enhanced nutritional and health-promoting attributes. This knowledge contributes to sustainable agriculture and supports the production of crops that align with consumer preferences and health trends.

The objective of this paper was to examine the total polyphenols, vitamin C and capsaicin contents of pepper (varieties: Garam F1, Alma, Poseidon, Promontor, Slovakia, Claudius, Bhut Jolokia, Serrano, and Candlelight) and their correlation with the antioxidant activity by using the high performance liquid chromatography and Folin-Ciocalteu method. The limit of detection for capsaicin was 0.09 µg.g⁻¹.Vitamin C and capsaicin ranged from 95.76 to 2,139 and from 44.40 to 2,224 μg.g⁻¹ dry matter (DM), respectively. The determined total polyphenol content (TPC) ranged from 4,230 to 9,939 mg GAE.kg⁻¹ DM and the values of antioxidant activity (AA) determined by using DPPH •, FRAP and ABTS • + methods were in range 19.48–91.81, 19.08–61.46 and 15.72–65.70 μmol TE.g⁻¹ DM, respectively. Based on the statistical evaluation, there was a high correlation between vitamin C content and antioxidant activity of peppers. The obtained results suggest that due to the composition of bioactive compounds, especially antioxidants, the consumption of pepper fruits is an ideal choice for the prevention of the cell damage.

Capsicum chili peppers are popular vegetables in Slovakia. They provide a supply of health-promoting substances, but contaminated vegetables can pose a serious health risk to the people who consume them. Therefore, the aim of this study was to determine the content of heavy metals (Mn, Zn, Cr, Cu, Ni, Cd, Pb and Hg) in the soil as well as in selected varieties of the genus Capsicum grown in southern Slovakia. The results were compared with the limit values given by the Law no. 220/2004 (valid in the SR) as well as threshold values proposed by the European Commission (EC) (2006). The gained result showed that the total content of Cd (1.64 mg/kg) as well as the available mobile forms of Cd (0.12 mg/kg) and Pb (0.26 mg/kg) was exceeded on the soil on which Capsicum cultivars were grown. The limit values of other monitored heavy metals (Mn, Zn, Cr, Cu, Ni, and Hg) were not exceeded. The studied species of the genus Capsicum did not accumulate monitored heavy metals. It can be stated that consumption of chili peppers does not pose any risk for human health.

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.

Sweet potatoes are reported to be a good source of bioactive compounds. The aim of this study was to evaluate the impact of different heat treatment methods (microwaving, steaming, and baking) and variety on the total polyphenol content and antioxidant activity of three sweet potato varieties – Beauregard (orange-fleshed), O’Henry (white-fleshed), and 414-purple (purple-fleshed). All investigated parameters were determined spectrophotometrically. The total polyphenol content was in the range of 0.53 (O’Henry) – 5.60 mg GAE.g-1 DW (414-purple) for raw flesh and 1.68 (O’Henry) – 7.03 mg GAE.g-1 DW (414-purple) for raw peel of sweet potatoes. Heat treatments caused an increase of total polyphenol content in sweet potatoes (0.98 (steamed O’Henry) – 28.04 mg GAE.g-1 DW (baked 414-purple)). In terms of antioxidant activity, the steamed samples of variety 414-purple showed the highest values of DPPH radical scavenging activity (4.51 µmol TE.g-1 DW) and Ferric reducing antioxidant power assay (19.57 µmol TE.g-1 DW) compared to the other treatment methods. Spearman´s test showed a strong positive relationship between both used methods for evaluation of antioxidant activity. All studied processing methods positively affected the total polyphenol content and antioxidant activity in sweet potatoes.

Garlic (Allium sativum L.) is one of the most commonly grown vegetables and thanks to its sensory properties, it has an important place in numerous world cuisines. Garlic is also known for its health-promoting properties, which are attributed to its chemical composition. The health benefits of garlic depending on the content of biologically active compounds, which vary between cultivars and geographical areas. Seven cultivars of garlic, namely Sukoradsky, Zahorsky, Germidour, Mojmir, Karel IV., Arkus, Makoi, were analyzed in this study. This study aimed to determine the total polyphenol content, total flavonoid content, and antioxidant activity of garlic. Studied characteristics were analyzed by the UV-VIS spectrometry method. Total polyphenol content ranged from 430.26 to 640.04 mg GAE.kg^-1 FW. Total flavonoid content ranged from 10.29 to 60.49 mg CE.kg^-1 FW. Antioxidant activity measured by ABTS assay ranged from 1.098 to 1.955 mmol TE.kg^-1 FW. Antioxidant activity measured by FRAP assay ranged from 0.63 to 1.467 mmol.kg^-1 FW. Highest TPC, TFC, and AA were determined in the cultivar Mojmir. The lowest TPC and TFC were determined in the cultivar Zahorsky. The lowest AA was determined in the cultivar Sukoradsky. High positive correlations were determined between individual parameters.