Magdaléna Valšíková

Antioxidant properties of European cranberrybush fruit (Viburnum opulus var. edule)

In the literature there is little available information concerning European cranberrybush fruit (Viburnum opulus var. edule). This plant can be cultivated, even in harsh climatic conditions, because of its low environmental demands, and it is possible to harvest the fruit even in the snow cover. The aim of this study was to determine the content of polyphenolics, antioxidant activity, flavonoids and vitamin C in the fruit of three cultivars ´Leningradskaya otbornaya´, ´Souzga´ and ´Taezny rubiny´ of this species. In the case of polyphenolics, high contents [up to 8.29 g of gallic acid/kg of fresh mass (FM)] were observed. The 1,1´-diphenyl-2-picrylhydrazyl (DPPH) and 2,2´-azinobis-3-ethyl-benzthiazino-6-sulphonic acid (ABTS) tests were applied to determine antioxidant activity, which was also high in comparison with other fruit species. The corresponding correlations between the polyphenolic content and antioxidant activity were in case of the DPPH test r2 = 0.88 and for the ABTS test r2 = 0.98. For comparison, the scavenging activity towards reactive oxygen species (superoxide anion, hydroxyl radical and nitric oxide) was determined by using a 25% fruit extract of particular cultivars. Antioxidant efficiency was also assessed using the rat liver slice model. Furthermore, the contents of flavonoids and vitamin C were assayed, giving values of 4.89 g/kg and 1.64 g/kg FM, respectively. The work should contribute to the popularization of this species as a promising crop plant in human nutrition.

Bioactive content and antioxidant capacity of Cape gooseberry fruit

At present, Cape gooseberry (Physalis peruviana) fruit is one of the less used raw materials of plant origin, which can be used for human nutrition. This fruit, as well as alimentary products made of it, were used by healers in folk medicine in the distant past. The aim of this study was to monitor and evaluate the antioxidant capacity of fresh fruit of three Cape gooseberry cultivars ‘Giant’, ‘Golden berry’ and ‘Inka’. Antioxidant capacity was also tested, on the basis of the scavenging effect of reactive oxygen species (ROS) and lipid peroxidation of methanolic extracts made of fresh fruit. These results were further extended and supplemented with determinates of the vitamin C and total phenolic contents. These analyses were made for three consecutive years. The highest values of antioxidant capacity were observed in the ‘Inka’ cultivar (9.31 grams of ascorbic acid equivalents kg−1 of fresh mass). In this cultivar, the obtained results were corroborated also in ROS and the contents of vitamin C and total phenolics. Due to a high antioxidant capacity of this fruit species, the results presented should increase its popularity above all as a promising raw material, which can be used for human nutrition.

FERTILISATION IMPACT ON THE CONTENT OF SELECTED BIOACTIVE COMPOUNDS IN CAULIFLOWER

Nitrogen and sulphur fertilization positively affected on crop yields and bioactive compounds (vitamin C, E1 and s-carotene) content in cauliflower edible heads. Applying fertilization doses of 250 kg N.ha-1 and 60 kg S.ha-1 compared to the control improved cauliflower harvest by 15,2 t.ha-1. Increased fertilization doses of nitrogen and sulphur significantly increased vitamin C and s-carotene content in the cauliflower. High significant difference in vitamin C level was found comparing the control variant and variant of nitrogen fertilization at the level of 200 kg N.ha-1. In percentage terms this is an increase in vitamin C level by 22,4%. Fertilization with increased doses of nitrogen and sulphur affected significantly the amount of s-carotene compared to unfertilized variant. Increased doses of N and S did not respond adequately to vitamin E1 content in cauliflower.

Effect of Bio-stimulants on Yield and Quality of Head Lettuce Grown Under Two Sources of Nitrogen

Biostimulants may enhance the yield and improve crop quality. Scientific reports, however, are still scarce, particularly for the intensive vegetable production area in Egypt. Therefore two field experiments were carried out in the two consecutive seasons in 2009/2010 and 2010/2011. The field trials were performed in sandy soil in the vegetable production in the, area, Giza Governorate (Centre of Egypt). The aim of this work was to evaluate the use of two bio-stimulants for reducing the nitrate content and improving the commercial quality of head lettuce. This study was arranged in a split plot experiment in three replications. The treatments included two nitrogen sources (ammonium nitrate and ammonium sulfate) as main plot and two bio-stimulants (FZB24® and Actiwave®) as sub-plot. The criteria measured were fresh and dry weights of leaves, number of leaves, yield and the contents of nitrogen, nitrate total sugars as well as chlorophyll and carotenoid contents. Results obtained showed that regardless of the nitrogen source, the FZB 24 and Actiwave at both rates significantly increased the leaf number, fresh and dry weights of leaves and the total yield. The highest contents of chlorophyll, total sugars, carotenoids and lower nitrate contents were found in lettuce leaves treated with FZB 24 and Actiwave at the increased rates. The nitrogen source application did not affect the fresh and dry weight of leaves, the yield, the total sugars and chlorophyll contents. Whereas, ammonium sulfate as a nitrogen source significantly increased the leaf number and decreased the nitrate content. Biostimulants exerted a positive role with regard to yield and quality of head lettuce.ZusammenfassungBiostimulanzien können den Ertrag und die Qualität positiv beeinflussen. Wissenschaftliche Untersuchungen hingegen sind rar und wurden bisher im intensiven Gemüseanbau Ägyptens kaum durchgeführt. Aus diesem Grunde wurden in den Jahren 2009/2010 und 2010/2011 Felduntersuchungen in der Gemüseanbauregion des Giza Gouvernements durchgeführt. Ziel der Untersuchung war die Bewertung des Einflusses von zwei Biostimulanzien bezüglich der Reduktion des Nitratgehalts sowie der Handelsqualität von Kopfsalat. Die Untersuchungen wurden als Spaltanlage mit drei Wiederholungen durchgeführt. Die untersuchten Verfahren beinhalteten zwei Stickstoffformen (Ammoniumnitrat und Ammoniumsultat) als Hauptgruppe und zwei Biostimulanzien in zwei Konzentrationen (FZB® und Actiwave®) als Untergruppe. Die gemessenen Parameter umfassten das Frisch- und Trockengewicht der Blätter, die Anzahl der Blätter, den Ertrag, den Stickstoff- und Nitratgehalt, die Gesamtzucker sowie die Chlorophyll- und Carotinoidgehalte. Unabhängig von der Stickstoffform erhöhten sowohl FZB 24 wie auch Actiwave bei beiden Konzentrationen signifikant die Blattanzahl sowie das Frisch- und Trockengewicht der Blätter und den Gesamtertrag. Die höchsten Gehalte an Chlorophyll, Gesamtzucker, Carotinoiden und Nitrat wurden bei den höheren Konzentrationen der Biostimulanzien gefunden. Die Stickstoffform übte keinen Einfluss auf das Frisch- und Trockengewicht der Blätter, den Ertrag, die Gesamtzucker- und die Chlorophyllgehalte aus. Ammoniumsulfat beeinflusste hingegen signifikant die Blattanzahl und reduzierte den Nitratgehalt. Biostimulanzien übten einen positiven Einfluss auf den Ertrag und die Qualität von Kopfsalat aus.

Changes of vitamin C content in celery and parsley herb after processing

Humans and other primates have lost the ability to synthesize vitamin C and therefore the only source is diet. Vitamin C or ascorbic acid has labile nature, it is removed or destroyed in specific degree immediately after harvest, but storage and post - harvest processing also contribute to its degradation. The aim of work was to determine the vitamin C content in the herb of selected celery and parsley varieties in dependence on chosen postharvest processing and to compare it with fresh herb. There were chosen five bulb forms varieties of celery (Apium graveolens) - Makara, Ilonaa, Hegy Koi, Talar and Diamant. In case of parsley (Petroselinum crispum) there were evaluated one variety of curly parsley, one variety of herb parsley - Petra, and five varieties of root parsley - Lenka, Eagle, Ginate D´Italia, Titana and Arat. Every variety was harvested in three terms, followed by vitamin C content estimation in fresh herb, after drying and after freezing. The content of vitamin C was estimated by HPLC method by the help of liquid chromatograph with UV detector. There was found the significant difference in content of vitamin C in parsley as well as in celery when comparing the fresh herb with herbs after post - harvest processes - drying (by air circulation in laboratory hall) and freezing. After processing of herbs in both observed species the vitamin C content decreased, in case of freezing it was about 65% (celery) and 61% (parsley), after drying about 86% (celery) and 82% (parsley) in comparison with fresh herb. The effect of processing played more important role in influencing of vitamin C content than variety in case of both selected species. For using of celery and parsley not only as culinary herb, but as a notable source of ascorbic acid it is the most important fresh herb intake.

Erratum to: Effect of Bio-stimulants on Yield and Quality of Head Lettuce Grown Under Two Sources of Nitrogen

the name of the second author was rendered incorrectly in the original publication but has since been corrected: instead of u. Schmidthalter it should read u. Schmidhalter.