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The objective of this study was to isolate resveratrol-producing endophytes of twelve wine grapes from the Uzbekistan vineyards. Of the thirty isolates twenty-six isolates were obtained from the peel of berries, and four isolates from the seeds. Predominant number of isolates belong to fungal endophytes. Almost all isolates were positive for resveratrol production in the preliminary screening. Extracts of only 6 isolates exhibited the actual presence of resveratrol in the range of 0.04 μg/ L - 130.5 μg/L by HPLC quantification. The most potent endophytic fungal isolate producing the highest intercellular resveratrol was GF-14 isolated from the Isabella variety. Further TLC and HPLC analysis confirmed the similarity of fungal resveratrol with standard resveratrol. Obtained data for the first time demonstrate that domestic vine grapes inhabited by resveratrol-producing endophytes. The endophytic isolate GF14 producing 300 μg/L of total fermentation medium could be promising candidate for further development into a commercial strain.

The auxin-synthesizing activity of endophytic fungi from desert halophyte plants Aeluropus litoralis, Halocnemum strobilaceum, Climacoptera crassa, Suaeda heterophylla were studied. In addition, screening of indole-3-acetic acid (IAA) was carried out at the cultivation of endophytes in the presence of 10% NaCl. All isolates produced IAA, but the highest level was observed in two Penicillium strains from C. crassa and H. strobilaceum, which produced significant amounts of extracellular IAA at a relatively low biomass level.

The controversy about the occurrence of an (ADPribosyl)ating activity in yeast is still standing up. Here we discuss this topic on the basis of results obtained with classic experiments proposed over years as basis to characterize an (ADPribosyl)ation system in any organism. Independent results obtained in two different laboratories were in line with each other and went towards the occurrence of an active (ADPribosyl)ating system in Saccharomyces cerevisiae. In fact data collected from nuclear preparations of cultured cells matched those from baker's yeast and lyophilized yeast cells. Yeast (ADPribosyl)ating enzyme is a protein of 80–90 kDa, as determined by electrophoresis on polyacrylamide gel in sodium dodecyl sulphate, followed by immunoblotting with antibodies against anti-poly(ADPribose) polymerase catalytic site. It synthesizes products, that, after digestion with phosphodiesterase, co-migrates mainly with phosphoribosyl adenosine monophosphate after thin layer chromatography on silica gel plate. © 2005 Wiley-Liss, Inc.