Authors:H. G. Daood, R. Tömösközi-Farkas, and J. Kapitány
In the present work, bio and conventional forms of spice red pepper were analysed using various high performance liquid chromatographic (HPLC) systems for their carotenoid, tocopherol and vitamin C contents. The carotenoid pigment was fractionated into free xanthophylls, monoesters, carotenes and diesters with newly developed reversed phase HPLC, while a-, b- and g-isomers of vitamin E were separated by normal phase chromatography. Ion-pair chromatography on a C-18 column provided good separation and quantification of vitamin C. The peppers included new resistant varieties and hybrids that are essential for bio-production. It was found that crossing new disease-resistant varieties such as Kaldom and Kalorez with susceptible ones such as Rubin and SZ-20 produced resistant hybrids that contained higher levels of quality components compared to the parents, particularly when grown and cultivated under organic farming conditions.
Authors:B. Schmidt-Szantner, M. Gasztonyi, P. Milotay, and R. Tömösközi-Farkas
A three-year (2016–2018) open field experiment was conducted to study the effect of irrigation, fertilisation, and seasonal variation on the main bioactive components, such as carotenoids (lycopene and β-carotene), total polyphenols, antioxidant capacity, and tocopherols of processed Uno Rosso F1 tomato. The statistical evaluation of measurements proved that the multi-year data set cannot be evaluated as combined data set; the values obtained in different years must be evaluated separately. The impact of irrigation on the content of bioactive components varied from year to year. The correlation was negative between irrigation and α-tocopherol content in 2016 and 2018 (r = –0.567 and –0.605, respectively), polyphenol content in 2016 (r = –0.668), γ-tocopherol content in 2017 (r = –0.662), while positive correlation was observed between concentration of vitamin C (r = 0.533) in 2017, lycopene content (r = 0.473) in 2018 and irrigation intensity. A weak correlation was proved between K levels and concentrations of lycopene and polyphenols in 2016 (r = 0.301 and r = 0.392, respectively).
Authors:R. Tömösközi-Farkas, M. Berki, M. Nagy-Gasztonyi, I. Wolf, and Zs. Polgár
We have investigated the Total Glycoalcaloid (TGA), nitrite, and nitrate contents of some Hungarian and foreign potato cultivars in relation to the effect of different combination of fertilisers and green manure, late blight management strategies (none, programmed, or prediction based spraying), and irrigation regime for three years. The Hungarian cultivars have exotic potato species like S. acaule, S. demissum, S. stoloniferum, S. vernei, or S. tub. ssp. andigenum in their genetic background as sources of resistance genes. No effect of fertilisers or irrigation was found on the level of glycoalkaloids and nitrate contents, which were influenced mostly by the genotype and season. In conclusion, the absolute amount and the presence of different antinutritive components of potato tubers were influenced by the technology, genotype, and season in a complex manner. These results in general prove that ware potato production utilising intensive commercial agrotechnical practices and common cultivars is safe regarding the nitrate and TGA content of tubers.
Authors:R.T. Mócsai, A. Maczó, C. Grünwald-Gruber, K. Majer-Baranyi, N. Adányi, P. Milotay, J. Czelecz, and R. Tömösközi-Farkas
Investigation of putative allergens from tomato berries is challenging as differences between human serum IgE specificity and reactivity as well as the non-specific binding of the primary and secondary antibodies often cause difficulties. In this study five tomato cultivars were investigated to evaluate their potential allergenicity in Hungarian tomato sensitive patients. The major allergens proved to be low molecular weight proteins, but several previously described allergens could be identified as well using IgE-Western blotting. IgE binding to cross-reactive carbohydrate determinants (CCDs) was ruled out through the use of CCD inhibitor, but non-specific binding of the secondary antibody remained an issue. IgE binding activity of a purified, immunoblot positive protein (band at 40 kDa), and non-specific binding of the secondary antibody to the same protein, was demonstrated with an Optical Waveguide Lightmode Spectroscopy (OWLS) based immunosensor. LC-ESI-MS/MS analysis showed this protein is an as-yet undescribed vicilin-type putative allergen.
Authors:R. Tömösközi-Farkas, Zs. Polgár, M. Nagy-Gasztonyi, V. Horváth, T. Renkecz, K. Simon, F. Boross, Z. Fabulya, and H. Daood
Anti-nutritive components in multi resistant potato cultivars were investigated in relation to conventional and organic farming for three years. Glycoalkaloids, nitrate, nitrite, asparagine, and glutamine contents of tubers were examined. Farming technology was found not to have an effect on the level of glycoalkaloids, which was influenced mostly by the genotype and season. Nitrogen fertilisation caused significant increase in nitrate, asparagine, and glutamine contents as compared to organic farming. Nitrite content was found to be more independent of farming technologies than nitrate. Tubers of cultivar Rioja had the lowest nitrate content irrespective of season or technology. In conclusion, the absolute amount and changes of different anti-nutritive components of potato tubers were influenced differently by the technology, genotype, and season in a complex manner. Organic farming had no effect on the glycoalkaloid content, but the nitrate levels had a tendency to be lower compared to conventional farming. This can be seen as a positive effect of organic farming.