Phenolic compounds were extracted from European and Japanese grapevine species (Vitis vinifera and V. coignetiae) seeds using 80% methanol or 80% acetone. The total content of phenolic compounds was determined utilizing Folin-Ciocalteu's phenol reagent, while the content of tannins was assayed by the vanillin and BSA precipitation methods. Additionally, the DPPH free radical and ABTS cation radical scavenging activities and the reduction power of the extracts were measured. The HPLC method was applied to determine the phenolic compounds, such as phenolic acids and catechins. The seeds contained large amounts of tannins and gallic acid and observable quantities of catechins, p-coumaric, ferulic and caffeic acids. The dominant form of phenolic acids in the extracts was the ester-bound form. The content of total phenolics was higher in the European grape V. vinifera seeds, which also contained more tannins, catechins and phenolic acids, except for caffeic acid. Extracts from V. vinifera seeds showed better radical scavenger properties and stronger reducing power. The total contents of phenolic compounds and tannins in acetone extracts were higher than in methanolic extracts. Acetone extracts also exhibited stronger antiradical properties as well as stronger reducing power.

Osmotic stress causes many adverse symptoms in plants, which include, for example, growth limitation and decrease or even absence of yield. Proteomic analyses of plant responses to stressors could lead to the introduction of crops with high resistance to osmotic stress. Such plants would be characterized by high yield even under unfavorable environmental conditions. In this article we describe changes in the protein profiles occurring in response to mild and moderate osmotic stress in triticale roots. Analysis of the protein profiles of these roots showed an increased abundance of 14 and a decreased abundance of 11 proteins under mild osmotic stress conditions while a moderate osmotic stress caused an increased abundance of 18 and a decreased abundance of 33 proteins. Twenty-five proteins, whose quantity altered under stress were identified using MALDI-TOF mass spectrometry. The identified proteins were classified into the categories of proteins associated with: defense mechanisms, metabolism, transcription, cell structure, protein synthesis, transport and signal transduction. The functions of identified proteins were discussed in relation to osmotic stress. Some of the identified proteins may be responsible for the adaptation of plants to adverse conditions.

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