Correlation between the levels of potassium and polyamines in the leaves of grapevine

Potassium and the most abundant polyamines (putrescine, spermidine and spermine) concentrations were determined in the leaf blades of Vitis vinifera L. cv. White Riesling, Ezerjó , Kövidinka, Chardonnay, Cabernet Sauvignon , Merlot, Kadarka varieties at ripening to characterize the correlation between these two types of osmolytes under drought stress and low nutrient supply. K+ concentration in the leaf blades changed in the range of 0.27-0.81% , indicating serious K+ deficiency . Kadarka and Ezerjó varieties accumulated the lowest and Kövidinka the greatest quantity of potassium. Below 0.5% K+ content the increase of free and soluble-conjugated putrescine concentration could be observed. The highest levels were formed in the leaves of Ezerjó: 1785 nmol/g fw. free and 589 nmol/g fw. soluble-conjugated putrescine and these values decreased to 11 nmol/g fw. and 14 nmol/g fw. at Kövidinka variety. Free spermidine concentration changed in the range of 25-100 nmol/g fw and the content of conjugated form was lower. The free and soluble-conjugated spermime levels remained below 20 nmol/g fw. Accumulation of spermidine and spermine didnot correlate with the K+ concentration in the leaf blades

Cultivation and antioxidative properties of pakuri (Inonotus obliquus) on low productive peatland forests

Abstrakti201

Kihokin viljelyä lääkekasviksi Pohjois-Satakunnan turvemailla - kestävää biotaloutta

201

Round-leaved sundew (Drosera rotundifolia) as a source of naphthoquinones for pharmacological purposes

Posteri201

Expression of catalase and retinoblastoma-related protein genes associates with cell death processes in Scots pine zygotic embryogenesis

201

Stability and Photoisomerization of Stilbenes Isolated from the Bark of Norway Spruce Roots

Stilbenes or stilbenoids, major polyphenolic compounds of the bark of Norway spruce (Picea abies L. Karst), have potential future applications as drugs, preservatives and other functional ingredients due to their antioxidative, antibacterial and antifungal properties. Stilbenes are photosensitive and UV and fluorescent light induce trans to cis isomerisation via intramolecular cyclization. So far, the characterizations of possible new compounds derived from trans-stilbenes under UV light exposure have been mainly tentative based only on UV or MS spectra without utilizing more detailed structural spectroscopy techniques such as NMR. The objective of this work was to study the stability of biologically interesting and readily available stilbenes such as astringin and isorhapontin and their aglucones piceatannol and isorhapontigenin, which have not been studied previously. The effects of fluorescent and UV light and storage on the stability of trans stilbenes were assessed and the identification and characterisation of new compounds formed during our experiments were carried out by chromatographic (HPLC, GC) and spectroscopic techniques (UV, MS, NMR). The stilbenes undergo a trans to cis isomerisation under extended UV irradiation by intramolecular cyclisation (by the formation of a new C-C bond and the loss of two hydrogens) to phenanthrene structures. The characterised compounds are novel and not described previously