Helmut Guttenberger

Influence of Altitudinal Variation on the Content of Phenolic Compounds in Wild Populations of Calluna vulgaris, Sambucus nigra, and Vaccinium myrtillus

This study deals with the effect of altitudinal variation on the content of phenolic compounds in three traditional herbal plants, which are also consumed as food in Central Europe. Herbs of Calluna vulgaris (L.) HULL, flowers and fruits of Sambucus nigra L., and berries of Vaccinium myrtillus L. collected in the Naturpark Solktaler (Austria) were extracted using accelerated solvent extraction (ASE). Identification and quantification of the constituents in the polar extracts (methanol 80%, v/v) were achieved by means of RP-HPLC-PDA and/or LC-PDA-MS analysis with external standards. 3,5- O-Dicaffeoylquinic acid was identified in flowers of S. nigra for the first time. Rising concentrations of flavonoids and especially flavonol-3- O-glycosides with adjacent hydroxyl groups in ring B in C. vulgaris and S. nigra with increasing altitude were observed. Anthocyanins from the berries of both S. nigra and V. myrtillus occurred in decreasing amounts with rising altitude. C. vulgaris showed the best radical scavenging capacity based on the DPPH assay.

Human Low Density Lipoprotein as a Target of Hypochlorite Generated by Myeloperoxidase

The aim of this study was to further clarify which part of human low density lipoprotein (LDL) is attacked by the MPO/H2O2/Cl- -system and which reactive oxygen species is responsible for the attack. Therefore the influence of this system on the modification of the lipid and protein moiety of LDL was studied in vitro. Using the monochlorodimedone assay it was found that HOCl is produced in micromolar quantities in the absence of LDL and is rapidly consumed by LDL in a concentration dependent manner. The consumption of HOCl was reflected in the formation of HOCl-specific epitopes on apo B-100 as determined by an antibody raised against HOCl-modified LDL. The absorbency at 234 nm was applied to measure continuously the extent of modification of LDL. The general kinetic pattern of the absorbency measurement consisted of a lag phase where no LDL modification was observed, followed by a rapid increase of absorbency and a plateau phase. Finally the absorbency decreased due to LDL precipitation. Time dependent absorption spectra indicated that this kinetic pattern is mainly caused by light scattering due to particle aggregation rather than by a specific absorption at 234 nm due to conjugated diene formation. In agreement with this finding a low rate of thiobarbituric acid reactive substances (TBArS) formation was observed after a lag phase. The aggregation of LDL occurs most likely by modification of apo B-100, which was determined fluorimetrically in terms of LDL-tryptophan destruction in presence of the MPO/H2O2/Cl(-)-system. The kinetic course of tryptophan fluorescence generally consisted of a rapid decrease leveling off into a low plateau phase. Gas chromatographic determinations of linoleic acid in LDL in presence of the MPO system showed that this polyunsaturated fatty acid (PUFA) is easily attacked by HOCl. Consistent with this finding NMR spectra of HOCl modified LDL indicated a complete disappearance of bis-allylic methylene groups. Since lipid peroxidation products only partially account for this loss of PUFAs, other reactions of HOCl with unsaturated lipids--probably chlorohydrin formation--must be involved. Summarizing, although the rate of lipid peroxidation is low, both the lipid and the protein moiety of LDL are readily modified by the MPO system. It appears that the immediate consequence of apo B-100 modification is its aggregation. It is concluded that MPO, which has been detected in atherosclerotic lesions, is able to contribute to the modification of LDL into a form recognizable for uncontrolled uptake by macrophages.

The effects of various soils, different provenances and air pollution on root tip chromosomes in Norway spruce

The classification of chromosomal aberrations was used to characterize different factors affecting chromosomes in the root meristem of Norway spruce [Picea abies (L.) Karst.] trees. It is important to know the most significant factor affecting the chromosomes in the root meristem of plants at natural sites. The results suggest that an intensive site effect is more significant than the soil or the provenance of the individual. This cytogenetic plant test system was also used to investigate 5-year-old spruce trees exposed in environmental chambers to elevated concentrations of carbon dioxide (750 cm3m−3) and ozone (0.08 cm3m−3) as single variables or in combination, and then transferred to a field for observation of a “memory effect”. The fumigated variants showed an increased number of chromosomal aberrations compared to the controls, which carried on as a memory effect in the root meristems far beyond the fumigation period.

Accession-Specific Haplotypes of the Internal Transcribed Spacer Region in Arabidopsis thaliana—A Means for Barcoding Populations

Eukaryote genomes contain multiple copies of nuclear ribosomal DNA (nrDNA) harboring both highly conserved and variable regions. This has made nrDNA the most popular genetic marker for phylogenetic studies and the region of choice for barcoding projects. Furthermore, many scientists believe that all copies of nrDNA within one nucleus are practically identical due to concerted evolution. Here, we investigate the model plant species Arabidopsis thaliana for intragenomic variation of the internal transcribed spacer (ITS) region of nrDNA. Based on a modified deep sequencing approach, we provide a comprehensive list of ITS polymorphisms present in the two most widely used accessions of A. thaliana-Col-0 and Ler. Interestingly, we found that some polymorphisms are shared between these genetically very distinct accessions. On the other hand, the high number of accession-specific polymorphisms shows that each accession can be clearly and easily characterized by its specific ITS polymorphism patterns and haplotypes. Network analysis based on the detected haplotypes demonstrates that the study of ITS polymorphism patterns and haplotypes is an extremely powerful tool for population genetics. Using the methods proposed here, it will now be possible to extend the traditionally species-bound barcoding concept to populations.

Photoprotective carotenoids and antioxidants are more affected by canopy position than by nitrogen supply in 21-year-old Pinus radiata

Photoprotection, light harvesting and light utilisation were investigated as a function of variation in N supply and canopy position in 21-year-old Pinus radiata D. Don. Chlorophyll fluorescence, gas exchange and photoprotective compounds were measured on lower, middle and upper canopy needles in trees receiving N fertiliser and in control trees not receiving N fertiliser. Irrespective of canopy height, additional N increased the light-harvesting capacity through greater contents of chlorophyll, neoxanthin and lutein, but did not affect light-utilisation processes, such as effective quantum yield of PSII or rates of net CO2 assimilation. Additional N fertiliser did not affect the concentrations of the measured photoprotective carotenoids (violaxanthin, antheraxanthin, zeaxanthin, α-carotene and β-carotene) or antioxidants (ascorbic acid, glutathione and α-tocopherol); however, carotenoids and antioxidants were strongly affected by canopy height and increased in concentration with increasing canopy height. The present study found that pools of photoprotective carotenoids and antioxidants were not driven by imbalances in light-harvesting and light-utilisation processes, but rather by gradients in light.

A perfusion chamber with temperature regulation.

When investigating microscopic preparations perfusion chambers allow exchange and regulation of different solutions and ensure their constant flow in the sample chamber. Temperature deviations, however, may be problematic. We describe a new chamber that contains an additional circulation system which regulates the inside temperature using an external thermostat. An integrated thermometer probe records the sample temperature, which appears on a monitor. The glass chamber, measuring 75 x 35 x 3 mm, provides good optical quality and is compatible with every type of microscope.

Multiple taxa in the Phoma-complex associate with black elder (Sambucus nigra L.)

The fungus Boeremia sambuci-nigrae (formerly Phoma sambuci-nigrae) causes the corymb wilt disease in elder (Sambucus nigra L.). Here, we assessed the genetic diversity of fungi within the Phoma-complex which associate with commercially cultivated elder in Styria (Austria). We sampled leaves, corymb stalks and berries of elder trees in one organically and in four conventionally managed orchards. In each orchard an area was left untreated allowing a sampling of fungicide treated and untreated trees. Nineteen taxa in the Phoma-complex were isolated and identified based on ITS and LSU nucDNA sequences. One isolate is closely related to Chaetosphaeronema, whereas the majority of the strains belong to the genera Epicoccum and Boeremia in Didymellaceae. Six isolates are monophyletic with Boeremia sambuci-nigrae. The results indicate a varying effectiveness of fungicide treatment for the different fungal groups investigated. The diverse distribution of isolates among the sampling sites suggests the influence of treatment effects and possibly also of climatic conditions.

Altitude Dependence of Thiol Content of Lichens

Summary The water soluble thiol (SH) content of lichens and its altitude dependence was investigated using an altitude profile of two lichen species. Further lichen species were investigated at different elevations for their SH-content. The poicilohydric lichens show a rise in SH-content with increasing altitude to a maximum between 1400–1600 m above sea level. At higher altitudes the content of SH declines again with increasing elevation.

Untersuchungen zur Morphologie und Nadelanatomie der F1-Generation einer Schlangenfichte

Summary Half sib offspring of a snake-spruce was investigated morphologically and compared with the normal form and the snake-spruce mother. In trees with increasing “snake” character the diameter of the stem, the branching and the height of the whole tree and the dry matter content of the needles increases. The needles of the snake-form are longer and broader. These larger needles result from an increase of cell size rather than from an increase of cell number. Snake forms are more xeromorphic: their cuticles are thicker, the stomatal chambers are deeper, and the number of sclereids is higher. The needles of snake-spruces have characters of light leaves.