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Our research aim was to investigate the quantitative composition of neochlorogenic acid, chlorogenic acid, rutin, hyperoside and isoquercitrin in leaves and fruit of introduced rowan plants to Lithuania using a HPLC method. In leaf and fruit samples, quantitative estimation of neochlorogenic acid (in leaf samples 1.11-11.49 mg/g, in fruit samples 0.93-5.43 mg/g), chlorogenic acid (in leaf samples 2.74-21.91 mg/g, in fruit samples 0.55-7.50 mg/g), rutin (in leaf samples 0.03-4.88 mg/g, in fruit samples 0.02-0.39 mg/g), hyperoside (in leaf samples 0.15-7.44 mg/g, in fruit samples 0.02-1.19 mg/g) and isoquercitrin (in leaf samples 0.75-5.24 mg/g, in fruit samples 0.02-0.65 mg/g) was performed. In leaf samples, the total content of identified phenolic compounds ranged from 7.18 to 35.74 mg/g. In fruit, raw material total content of neochlorogenic acid, chlorogenic acid and identified flavonoids varied from 2.24 to 11.19 mg/g. Comparison of raw material samples of Sorbus species according to their quantitative composition of identified phenolic compounds using cluster analysis singularized S. commixta leaf and fruit samples. These contained the highest contents of chlorogenic acid, hyperoside and isoquercitrin, but also the lowest contents of neochlorogenic acid and rutin. The highest contents of neochlorogenic acid were recorded for S. lancifolia leaves, and of rutin for S. anglica leaves.

Qualitative and quantitative composition of anthocyanins in bilberry (Vaccinium myrtillus L.) fruits was assayed. The aim of our study was to evaluate total anthocyanin content and their composition in bilberries collected from various regions and at different time. For the quantification of total anthocyanins in frozen fruits, the spectrophotometrical assay was performed. The highest amount of anthocyanins in bilberry fruits, collected in Lithuania, was found in samples from Šilutė (0.399%), the lowest one – from Valkininkai region (0.264%), but higher amounts of anthocyanins were found in the samples collected in Russia (Archangelsk region) and Sweden (Stockholm region). High-performance liquid chromatography was applied for qualitative evaluation of individual anthocyanins in the different material. Quantification of anthocyanidin content was performed after acidic hydrolysis of anthocyanin glycosides. Chromatographic analysis has shown that there are no differences in qualitative composition of anthocyanidins. In all samples, cyanidin was found in the highest quantities (mean amount 0.053 µg/mL). Delphinidin and petunidin was found in quantities 2.5 fold lower than cyanidin, and malvidin and peonidin were found in the smallest quantities. Only in the blueberries collected in Sweden, malvidin was found in the highest amount. It was 1.5 fold higher than amounts of petunidin and delphinidin.

Complex investigations designed to explore the impact of extensive, organic-sustainable and conventional-chemical farming systems on changes of soil chemical, physical and microbiological properties of sandy loam Haplic Luvisol (LVh) were performed at the Vokė Branch of the Lithuanian Research Centre for Agriculture and Forestry during [2003][2004][2005][2006][2007][2008][2009][2010][2011][2012]. The studies were carried out employing different crop rotations, where the plant sequence was laid out in four treatments so that the plant residues in the soil would accumulate more organic matter and nitrogen. Research evidence showed that different farming systems and plant sequences in rotations did not affect soil acidity, but significantly increased the contents of total nitrogen and organic carbon and reduced the contents of available phosphorus and potassium. Soil physical properties changed accordingly. Higher moisture levels were determined in soil under extensive and conventional-chemical farming systems. At the lower soil layers the impact of green manure on the reduction of soil bulk density and increase of total and air-filled porosity was evident. Extensive and conventional-chemical farming systems favoured the distribution of fungi in the soil. With the application of organic farming system, the balance between the number of ammonifying and mineral nitrogen assimilating bacteria was maintained.

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