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Bozhinova R.,Tobacco and Tobacco Products Institute
Bulgarian Journal of Agricultural Science

The effects of the different phosphorus rates (0; 75 and 225 kg ha-1) on heavy metal concentrations in soil and tobacco plants have been studied in a stationary field trial. A long-term fertilizer experiment with continuous tobacco cropping system was established on rendzina soil (Rendzic Leptosols) in 1966. Although P fertilizers are considered a source of anthropogenic contamination of soil, the application of increasing P rates did not increase the total Cd, Pb and Cu content in the soil. Slightly higher Ni concentration was observed in plots receiving supplemental P fertilizer as compared to 0 kg P2O5 ha-1 treatment. The changes in the available Cd and Pb content as a result from the long-term P fertilization are insignificant. There was significant increase of available Ni and Cu in the plots treated with 225 kg P2O5 ha-1 compared to the 0 kg P2O5 ha-1 treatment. Increasing levels of P fertilization had no pronounced effect on Cd, Pb and Ni concentrations in leaves. Copper content in leaves decreased with the increase of P fertilizing levels. Therefore, the impact of phosphate fertilizer application on Cd, Pb, Ni and Cu content in soils and tobacco plants was proved to be limited. Under our experimental conditions, the risk of heavy metals’ accumulation in soil and tobacco associated with long-term P fertilization was low. © 2016, National Centre for Agrarian Sciences. All rights reserved. Source

Hristov Hr.,Plovdiv University | Balabanov N.,Plovdiv University | Marinova S.,Plovdiv University | Zaprianova P.,Tobacco and Tobacco Products Institute | And 5 more authors.
AIP Conference Proceedings

The report presents the results from research of contents of U and Th in soil samples from the region of the Belene Nuclear Power Plant (NPP). The report presents the investigations for sorption of U in the system soil-water from region. The report presents similarly the results for the natural radiation background - about 0,14 μSv/h, for the investigated region. © 2009 American Institute of Physics. Source

Docheva M.,Tobacco and Tobacco Products Institute | Dagnon S.,Plovdiv University | Statkova-Abeghe S.,Plovdiv University
Natural Product Research

The flavonoid-rich natural products exert a wide range of pharmacological properties. This investigation aimed at obtaining extracts from tobacco cultivars and waste enriched with flavonoids and purified from nicotine and phenolic acids, and evaluating their radical scavenging potential. Extraction with a mixture of ethyl acetate-methanol (1:1, v/v) was employed resulting in 100% yield for flavonoids and 36% yield for phenolic acids. The crude extracts were purified using preparative column chromatography on silica gel. The content of flavonoids in the purified extracts varied from 8.8 ± 1.1% to 14.3 ± 1.8%. Nicotine was not detected in amounts higher than 0.3 g mL-1. The content of phenolic acids was lower than 1.0%. The radical scavenging potential of extracts from tobacco cultivars exhibited values from IC50 = 35.0 ± 3.1 to 64.6 ± 7.5 g mL-1. The extracts obtained by the proposed procedure are enriched with flavonoids with high radical scavenging potential and are purified from nicotine and phenolic acids. They can be regarded as potential biopharmaceuticals. © 2014 Taylor & Francis. Source

Ivanov K.,Plovdiv University | Zaprjanova P.,Tobacco and Tobacco Products Institute | Petkova M.,Plovdiv University | Stefanova V.,Plovdiv University | And 3 more authors.
Spectrochimica Acta - Part B Atomic Spectroscopy

The most widely used method for determination of total phosphorus in soils is perchloric acid digestion, followed by a colorimetric assay to measure the concentration of P in solution. The first part of this study compares an alternative digestion method, using aqua regia (ISO 11466 and EPA Method 3052), with perchloric acid digestion procedure, and also compares inductively coupled plasma mass spectroscopy (ICP-MS) with colorimetry for the measurement of P on the basis of five internationally certified standard soils and 20 real-life soils with widely different extractability of phosphorus. The phosphorus concentration was determined by means of the reduced phosphomolybdenum blue and ICP-MS. The relationship between methods has been examined statistically. Good agreement of the results from colorimetry and ICP-MS was established for all certified soils. The microwave-assisted digestion with aqua regia was comparable, both in precision and accuracy, with the hot plate aqua regia method. The phosphorus concentration found with the HF + HClO 4 digestion method was in good agreement with the certified mean values, while the superiority in extracting phosphorus, when compared to other methods, was obvious. Soil testing for plant-available phosphorus in Bulgaria and many European countries is most commonly conducted using acid Ca-lactate extraction (Egner-Riehm test) and alkaline sodium bicarbonate extraction (BDS ISO 11263:2002), based on Olsen test, followed by a colorimetric assay to measure the concentration of P in solution. The second part of this study reports the differences between Egner-Riehm test and BDS ISO 11263:2002 measured colorimetrically and by ICP-MS. Fifty soils were selected from South Bulgaria to represent a wide range of soil properties. It was established that ICP-MS consistently yielded significantly higher P concentrations than the colorimetric method in both extraction tests, and the relative differences were greatest in soils with lower P concentrations. © 2012 Elsevier B.V. Source

Dimanov D.,Tobacco and Tobacco Products Institute | Masheva V.,Tobacco and Tobacco Products Institute | Dimitrova D.,Plant Genetic Resources Institute K Malkov
Bulgarian Journal of Agricultural Science

It has been researched the possibility for in vitro N. tabacum sp., S. tuberosum sp., S. lycopersicum sp. Cultivars at a different nutritive mediums. A positive effect of liquid nutrient media on micropropagation in vitro in three Solanaceae species, compared to solid agar medium was established. The best for micropropagation in vitro in the varieties of three species - N. tabacum, S. tuberosum and S. lycopersicum is nutritive medium B. The importance of genotypein the reproduction in vitro has been demonstrated. The unified systeme for micropropagation in vitro - based on nutritive medium B of varieties of three family Solanaceae species was created. Source

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