Renata Kazimierczak

Beetroot (Beta vulgaris L.) and naturally fermented beetroot juices from organic and conventional production: metabolomics, antioxidant levels and anticancer activity

BACKGROUND The aim of the paper was to determine the level of antioxidants and metabolomic fingerprinting in both raw beetroots and naturally fermented beetroot juices from organic (ORG) versus conventional (CONV) production. In addition, the anticancer properties of the fermented beetroot juices were evaluated. RESULTS The obtained results showed that ORG fresh beetroots contained significantly more dry matter, vitamin C and some individual phenolic compounds than CONV beetroots. The content of total phenolic acids was significantly higher in CONV beetroots compared with the ORG ones. The level of flavonoids was similar in ORG and CONV beetroots. There were only slight differences in the chemical composition of ORG and CONV beetroot juices. Metabolomic analysis provided a possibility to distinguish clearly between ORG and CONV fermented beetroot juices. However, this method was less useful in the case of fresh whole beetroots. It was found that anticancer activity was stronger in the case of ORG fermented juices when compared with CONV ones. CONCLUSION The obtained results indicate that ORG- and CONV-produced beetroots and fermented beetroot juices have different chemical properties and different impacts on cancer cells. It is necessary to continue research on this topic in order to confirm and understand the achieved results.

Effects of dietary nitrate supplementation on the oxygen cost of exercise and walking performance in individuals with type 2 diabetes: a randomized, double-blind, placebo-controlled crossover trial

Dietary nitrate supplementation has been shown to reduce the oxygen (O2) cost of exercise and enhance exercise tolerance in healthy individuals. This study assessed whether similar effects could be observed in individuals with type 2 diabetes (T2DM). In a randomized, double-blind, placebo-controlled crossover study, 48 participants with T2DM supplemented their diet for 4 days with either nitrate-rich beetroot juice (70ml/day, 6.43mmol nitrate/day) or nitrate-depleted beetroot juice as placebo (70ml/day, 0.07mmol nitrate/day). After each intervention period, resting plasma nitrate and nitrite concentrations were measured subsequent to participants completing moderate-paced walking. Pulmonary gas exchange was measured to assess the O2 cost of walking. After a rest period, participants performed the 6-min walk test (6MWT). Relative to placebo, beetroot juice resulted in a significant increase in plasma nitrate (placebo, 57±66 vs beetroot, 319±110µM; P < 0.001) and plasma nitrite concentration (placebo, 680±256 vs beetroot, 1065±607nM; P < 0.001). There were no differences between placebo juice and beetroot juice for the O2 cost of walking (946±221 vs 939±223ml/min, respectively; P = 0.59) and distance covered in the 6MWT (550±83 vs 554±90m, respectively; P = 0.17). Nitrate supplementation did not affect the O2 cost of moderate-paced walking or improve performance in the 6MWT. These findings indicate that dietary nitrate supplementation does not modulate the response to exercise in individuals with T2DM.

Three-Year Comparative Study of Polyphenol Contents and Antioxidant Capacities in Fruits of Tomato (Lycopersicon esculentum Mill.) Cultivars Grown under Organic and Conventional Conditions

In the present study, four tomato cultivars were grown under organic and conventional conditions in separate unheated greenhouses in three consecutive years. The objective was to assess the influence of the cultivation system on the content of individual polyphenols, total phenolics, and antioxidant capacity of tomatoes. The fruits were analyzed for total phenolic content by the Folin-Ciocalteau method and antioxidant capacity by the DPPH free radical scavenging assay. Individual phenolic compounds were analyzed using HPLC-DAD-MS/MS. Among 30 identified and quantified polyphenols, significantly higher contents of apigenin acetylhexoside, caffeic acid hexoside I, and phloretin dihexoside were found in all organic samples. The content of polyphenols was more dependent on year and cultivar than on cultivation conditions. Generally, the cultivation system had minor impact on polyphenols content, and only a few compounds were influenced by the mode of cultivation in all tested cultivars during all three years.

Effects of organic and conventional production systems on the content of bioactive substances in four species of medicinal plants

This paper aimed to compare the content of compounds with antioxidant properties in four species of medicinal plants, rosemary, peppermint, lemon balm and sage grown under organic and conventional conditions in 2 consecutive years. The dry matter and vitamin C content was determined according to Polish Standards; carotenoids and polyphenols were analysed by high-performance liquid chromatography. Organic medicinal plants contained significantly more dry matter, vitamin C, phenolic acids and total flavonoids than the plants from conventional production. On the other hand, conventional plants contained significantly more carotenoids than the organic ones. A high content of beneficial bioactive compounds in medicinal plants, especially coming from organic farming, is an important prerequisite for their use in a healthy diet.

The Effects of Organic and Conventional Cultivation Systems on the Content of Bioactive Substances in Herbal Plants

The Effects of Organic and Conventional Cultivation Systems on the Content of Bioactive Substances in Herbal Plants Five species of herbs from organic and conventional cultivation (dropsy plant, lovage, mint, thyme and sage) were used for this experiment. The research material consisted of usable parts of fresh herbs, which were harvested in the first ten days of September 2009 and 2010. In order to avoid losses in the content of biologically active compounds in the plant material, the herbs were frozen at -80°C immediately after harvesting, and then subjected to freezedrying; finally, analytical research was conducted. The results of two-year studies indicated that herbal plants from organic production contained a higher level of dry matter, vitamin C and flavonoids, while the conventional ones contained more phenolic acids. Regardless of the cultivation system, dropsy plant and mint were distinguished by the content of phenolic acids, the highest level of flavonoids was found in thyme, while lovage was the raw material containing the most vitamin C. The qualitative analysis of phenolic compounds contained in herbs showed that the most diverse composition of phenolic acids was attributed to sage and thyme, which also contained the largest number of identified flavonoids. Wpływ Ekologicznego i Konwencjonalnego Systemu Uprawy na Zawartość Substancji Bioaktywnych w Roślinach Zielarskich Badaniami objęto pięć gatunków roślin zielarskich: melisa lekarska, lubczyk ogrodowy, mięta pospolita, tymianek pospolity i szałwia lekarska, które pochodziły z uprawy ekologicznej i konwencjonalnej. Materiał do badań stanowiły części użytkowe świeżych ziół, zebrane w pierwszej dekadzie września 2009 i 2010 roku. Aby uniknąć strat w zawartości związków biologicznie czynnych w materiale roślinnym, natychmiast po zbiorze zioła zostały zamrożone w temperaturze -80°C, a następnie poddano je liofilizacji, po czym przeprowadzono badania analityczne. Dwuletnie wyniki badań wykazały, że zioła z produkcji ekologicznej zawierały więcej suchej masy, witaminy C i flawonoidów, natomiast zioła konwencjonalne odznaczały się wyższą zawartością kwasów fenolowych. Niezależnie od systemu uprawy, pod względem zawartości kwasów fenolowych wyróżniały się melisa i mięta, najwięcej flawonoidów stwierdzono w tymianku, natomiast surowcem, który zawierał najwięcej witaminy C był lubczyk. Analiza profilu związków fenolowych zawartych w ziołach wykazała, że najbardziej urozmaiconym składem kwasów fenolowych odznaczały się szałwia i tymianek, który jednocześnie zawierał największą ilość zidentyfikowanych flawonoidów.

Polyphenols, tannins and caffeine content and antioxidant activity of green teas coming from organic and non-organic production

Among infusions of green teabags and leafy green teas from organic and non-organic production systems we measured and compared the content of phenolic acids, flavonols and total polyphenols by spectrophotometry, the content of tannins by titration and the content of caffeine by high-performance liquid chromatography (HPLC). In addition, the antioxidant activity of the infusions was determined by spectrophotometry. The results obtained have shown that organic teas contained significantly more flavonols and tannins. However, the content of phenolic acids was higher in non-organic teas. The teas from organic and non-organic production did not differ in terms of total polyphenol content and antioxidant activity. There were no differences in leaf teas in relation to the teabags in contents of phenolic acids, tannins and total polyphenols. Organic teas had higher content of catechin C than the non-organic ones, but at the same time non-organic teas had more epigallocatechin 3-gallate (EGCG) in comparison to organic teas. Epigallocatechin (EGC) and epicatechin (EC) were not found to be different between the two groups of tea. Catechin was found to be significantly higher in teabags, while the EGCG was higher in leaf teas. The reason for this may be the oxidation of teabags, which have a greater exposed surface area. There was no appreciable effect of the form of tea on the content of tannins, caffeine, flavonols, phenolic acids, total polyphenols, EGC and EC as well as the antioxidant activity of the tea infusions examined.

The Nutritive Value of Organic and Conventional White Cabbage (Brassica Oleracea L. Var. Capitata) and Anti-Apoptotic Activity in Gastric Adenocarcinoma Cells of Sauerkraut Juice Produced Therof

White cabbage is one of the most important vegetables grown both in Poland and worldwide. Cabbage contains considerable amounts of bioactive compounds such as glucosinolates, vitamin C, carotenoids, and polyphenols. Some experiments indicate that vegetables from organic production contain more bioactive compounds than those from conventional production, however, only a few studies have been conducted on cruciferous plants. The presented study has proved that organic fresh cabbage, compared to the conventional one, contained significantly less total flavonoids in both years of experiments (3.95 ± 0.21 mg/100 g FW and 3.71 ± 0.33 mg/100 g FW), several flavonoid compounds, total chlorophylls (1.51 ± 0.17 mg/100 g FW and 1.30 ± 0.22 mg/100 g FW) carotenoids, nitrites (0.55 ± 0.04 mg/kg FW and 0.45 ± 0.02 mg/kg FW), and nitrates (0.50 ± 0.13 g/kg FW and 0.47 ± 0.11 g/kg FW). The organic sauerkraut juice, compared to the conventional one, contained significantly more total polyphenols (5.39 ± 0.22 mg/100 g FW and 9.05 ± 1.10 mg/100 g FW) as well as several flavonoids. Only CONV sauerkraut juice produced with the highest N level of fertilization induced a statistical significant increase of the level of necrosis of human stomach gastric adenocarcinoma cell line AGS.

Charakterystyka europejskich konsumentów żywności ekologicznej – motywy, działania i implikacje

The aim of the study was to analyze the motives and to characterize the profile of European organic food consumer using available literature data. According to the research published so far, organic food consumers are, e.g., better educated and more physically active compared to those who declare no interest in organic foods. They also exhibit nutritional patterns more closely adhering to current dietary guidelines, and show lower probability of overweight and obesity. Most of them do not smoke. Among the reasons to buy organic food, most of the consumers mention health in the first place, followed by the environmental aspects, animal welfare and taste.