A study was conducted to analyse the carotenoids by high-performance liquid chromatography (HPLC) using reversed-phase cross linked end-capping and to study the pigment content and composition in sea buckthorn products as well as in freshly harvested fruits from peach thees grown under organic and integrated farming conditions. It was found tha...t carotenoids in fruits of both crops occur mainly esterified with fatty acids in form of mono- and di-esters. The major carotenoids were esters of zeaxanthin, lutein, β-cryptoxanthin and β-carotene. The major carotenoids showed different response to processing of sea buckthorn being highly sensitive to thermal treatments such as blanching, cooking and drying. Significant differences were found between peach varieties in their carotenoid content, whereas the impact of organic farming on carotenoids formation was found to be variety-dependent. Two of the three varieties examined in this work, when cultivated under organic farming conditions contained lower carotenoid level as compared to that found in the fruits of the same varieties but produced in integrated farms.
The influence of the foliar nutrition on the pear fruit quality (Pyrus communis L.) cv. 'Williams' was studied in years 1997 and 1998. We determined the contents of individual sugars (glucose, fructose, sucrose and sorbitol) and organic acids (malic, citric, fumaric and shikimic) by HPLC (High Performance Liquid Chromatography). The si...zes of the fruits (diameter, length, weight) were measured as well as the amounts of soluble solids and titrable acids. The experiment comprised two treatments: the foliar nutrition and the control. In the treatment of foliar nutrition the trees were sprayed five times (from May 22 to July 7) with a foliar fertilizer, which contained 15% of P205, 20% of K20, 0.1% of Mn, 0.1% of B and 0.1% of Mo. The foliar nutrition influenced higher quantities of sugars (glucose, sorbitol, soluble solids) and organic acids (malic, citric) but had no effect on the contents of shikimic acid, pH juice and titrable acids. At the treatment of foliar nutrition a trend of decrease in the contents of fructose, sucrose, fumaric acid, boron, and zinc was noticed.
The content of different auxins of soft-wood cutted plum rootstock 'Marianna GF8/1' (Prunus cerasifera x P. munsoniana) was determined during the rooting period. The level of auxin-concentration (exogenous and endogenous) of basic and intemodal part of cuttings was determined by WATERS HPLC equipment every 7 days during rootin...g period. The lengths soft wood cuttings were app. 30 cm long. The basal part of shoots were treated with 2000 pg/g concentrated indole-butiryc acid in talcum powder. After treatment the cuttings were placed in propagation green-house under intermittent mist. The plant hormones were extracted by methanol the solution was cleaned by paper-filter, and further cleaned by centrifuge. The effluent was examined by reversed phase High Performance Liquid Chromatography, with WATERS 2487 dual detector at 220 am on Symmetry C18 4,6x 150 column. Recovery and reproducibility assessment indicates good accuracy and acceptable relative standard deviation (RSD) 5%. Linear responses (r20.997) for calibration curve was obtained with IAA, IPA and IBA standard in range, with a limit of quantification of 0.15 g•m1-1. The concentration of IAA, IPA and IBA in the basal part of cuttings were measured, during the rooting period. We proved the external IBA was taken up by the plants. In the plants were found the IBA, and the IAA concentration of IBA treated cuttings was higher, than the untreated one.