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The bulk formation of yeast-like (arthrospore-like) cells were typical in carbon-depleted submerged cultures of the high β-lactam producer Penicillium chrysogenum NCAIM 00237 strain independently of the nitrogen-content of the culture medium. This morphogenetic switch was still quite common in carbonstarving cultures of the low-penicillin-producer strain P. chrysogenum ATCC 28089 (Wis 54-1255) when the nitrogen-content of the medium was low but was a very rare event in wild-type P. chrysogenum cultures. The mycelium→yeast-like cell transition correlated well with a relatively high glutathione concentration and a reductive glutathione/glutathione disulfite (GSH/GSSG) redox balance in autolysing cultures, which was a consequence of industrial strain development. Paradoxically, the development of high β-lactam productivity resulted in a high intracellular GSH level and, concomitantly, in an increased γ-glutamyltranspeptidase (i.e. GSH-decomposing) activity in the autolytic phase of growth of P. chrysogenum NCAIM 00237. The hypothesized causal connection between GSH metabolism and cell morphology, if verified, may help us in future metabolic engineering of industrially important filamentous fungi.

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A key driver of biodiversity loss is human landscape transformation. Change detection and trajectory analysis are frequently applied methods for studying landscape change. We studied to what degree habitat-specific change detection and trajectory analysis provide different information on landscape change compared to the analysis with land-cover statistics. Our research was carried out at two spatial scales (regional, 1800 km2, 360 random points; local, 23 km2, polygon-based maps) in the Kiskunság, Hungary. Spatio-temporal databases were prepared using historical maps, aerial photos and satellite images from 1783, 1883, 1954, and 2009. Local expert knowledge of landscape history and recent vegetation was used during the historical reconstructions. We found large differences at both scales between land-cover based and habitat-specific analyses. Habitat-specific change detection revealed that grassland loss was not continuous in the different habitats, as land-cover based analysis implied. Ploughing affected open sand grasslands and sand steppes differently in the periods studied. It was only apparent from the habitat-specific analyses that from the grasslands only mesotrophic and Molinia meadows were relatively constant, up until the 1950s. The gradual increase in forest area revealed by land-cover CHD analyses was split into natural and anthropogenic processes by habitat-specific analyses. Habitat specific trajectory analysis also revealed ecologically important historical differences between habitats. Afforestation affected especially the open sand grasslands, whereas wetland habitats were relatively stable. The most important trajectory was the one in which closed sand steppes were ploughed during the 19th century, and remained arable fields until present. Fifty percent of the regional trajectories of 18th century open sand grasslands terminated in tree plantations at present, though 82% of the current open sand grasslands of the local site can be regarded as ancient. We concluded that dividing land-cover categories into finer habitat categories offered an opportunity for a more precise historical analysis of key habitats, and could reveal important ecological processes that cannot be reconstructed with land-cover based analyses. It also highlighted habitat-specific processes making natural and social drivers better interpretable. Information on the diversity of habitat-histories may serve as a basis for spatially more explicit conservation management.

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In this paper, we elaborated a new concept (the Regularities-Deviations-Uniqueness; RDU framework) to analyse regional vegetation patterns and applied it to the Pannonian region of the Carpathian Basin. We introduced three criteria, namely: distributional regularity, distributional deviation, and compositional uniqueness. Regularities conform to the pattern expected based on macroclimate and relief. Deviations are singular phenomena and are defined as the conspicuous departures from the regular pattern at odds with either zonal pattern (climate rules), or the repetitive extrazonal patterns (relief and meso-climate interactions). Endemic plant communities of the Pannonian region (defined by a unique species composition) are regarded as the unique features. The main regularities recognised for the Pannonian region are: (1) the altitudinal pattern of vegetation belts, (2) the horizontal zonation of the Dunántúl, (3) the gradient of continentality along the mountain ranges, and (4) the circular zonality of the Nagyalföld. Deviations are mostly explained by local vegetation history, mesoclimate, and edaphic factors. The major deviations include (i) occurrence of mixed Pinus sylvestris forests in Őrség, (ii) cool continental forest-steppe forests on Kisalföld, and Gödöllői-dombvidék, (iii) the direct contact of Fagus and Quercus pubescens forests (Bakony, Balatonfelvidék), (iv) the Fraxinus excelsior-Tilia spp. forests on rock outcrops, and (v) the Sphagnum bogs on the Alföld. Individuality of the Pannonian region is demonstrated by the endemic zonal forest-steppe forests and intrazonal endemic communities such as the Cerasus mahaleb-Quercus pubescens forests, and the vegetation on calcareous sand, dolomite and saline soils and the like. We argue that the introduced criteria are suitable for the entitation and description of other biogeographical regions, and offer useful tool for interregional comparisons.

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Acta Alimentaria
Authors:
Zs. Molnár
,
Sz. Bánvölgyi
,
Á. Kozák
,
I. Kiss
,
E. Békássy-Molnár
, and
Gy. Vatai

Concentration of raspberry (Rubus idaeus L.) juice by combination of membrane processes was investigated. The pre-treatment steps were crushing, enzyme treatment, pressing and clarification by microfiltration (MF). Ceramic tube MF membrane was used at low pressure and temperature (3.9 bar and 30 °C).Nanofiltration (NF) and reverse osmosis (RO) process with flatsheet membranes was studied to pre-concentrate the clarified and sterilized raspberry juice. The NF experiments were carried out at different flow-rates (400 l h−1 and 600 l h−1). Any significant effect of flow-rate was not experienced. Both pre-concentration processes were used at low temperature (30 °C) for a mild concentration of raspberry juice. For further concentration osmotic distillation (OD) was applied. The initial total soluble solid content of the raspberry juice was 8–10 °Brix, the final concentrate of OD was 70–80 °Brix.The membrane-, fouling- and the polarization layer resistance were determined in case of micro-, nanofiltration and reverse osmosis.The soft drinks, made from RO and OD concentrates, were compared with well-known conventional raspberry juice from trade. During the sensory analysis (the colour, odour, flavour, acid taste and general impression was evaluated) our juices were preferred by customers.The antioxidant capacity, total phenol, anthocyanin and acid content, the total cell count and the number of yeasts and moulds were determined in the permeate and retentate samples of the different filtration steps.

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Triticum monococcum represents an important source of useful genes and alleles that it would be desirable to use in wheat breeding programmes. The well-defined landmarks on the Am chromosomes could accelerate the targeted introgression of T. monococcum chromatin into the wheat genome.Fluorescence in situ hybridization (FISH) using the repetitive DNA probes pSc119.2, Afa family and pTa71 showed that the pSc119.2 probe was not suitable for the identification of Am chromosomes. In contrast, the whole set of Am chromosomes (especially chromosomes 1, 4, 5 and 7) could be discriminated based on the hybridization pattern of pTa71 and Afa family. In situ hybridization with microsatellite motifs (GAA, CAG, AAC and AGG) proved that SSRs represent additional landmarks for the identification of Am chromosomes. The most promising SSR probes were the GAA and CAG motifs, which clearly discriminated the 6Am chromosome and, when used in combination with the Afa family and pTa71 probes, allowed the whole set of Am chromosomes to be reliably identified.In conclusion, fluorescence in situ hybridization using the repetitive DNA probes Afa family and pTa71, combined with SSR probes, makes it possible to identify the Am chromosomes of T. monococcum and to discriminate them from Au chromosomes in the polyploid wheat background.

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The subject of the present study is the monitoring of the hardwood groves at the Martonvásár Manor Park with the involvement of 20 earlier (recorded in 1980–1981) and 20 current (recorded in 2011–2012) phytocoenological relevés. The manor park was created in the first half of the 19th century. Since then the woods along the St László stream have developed into species-rich and semi-natural forests, which can be identified as related to the oak-ash-elm groves (Scillo vindobonensis-Ulmetum) of the Zámoly Basin and the Csepel Island. The results of the current monitoring repeated 30 years after the first survey show momentous changes in forest dynamics such as the ageing-related opening of the upper canopy and an intense closure of the lower canopy and shrub layer. The ratio of the invasive species doubled. Present findings may provide additional information for long-term forest ecology research, however, results could be considered as changes of a semi-natural hardwood forest with minimal human impact.

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Acta Alimentaria
Authors:
Sz. Bánvölgyi
,
T. Vatai
,
Zs. Molnár
,
I. Kiss
,
Ž. Knez
,
Gy. Vatai
, and
M. Škerget

Two novel technologies were applied in order to investigate concentration and formulation of anthocyanins for potential use in food industry. Integrated membrane process technology was applied for concentrating elderberry juice. In the first step, the juice was clarified by microfiltration, followed by a pre-concentration step with reverse osmosis. Finally, the juice was concentrated to the end concentration of 56 °Brix by osmotic distillation. The elderberry juice concentrate was formulated in a powderous form by a high-pressure process — Particles from Gas Saturated Solution (PGSS™) — using supercritical CO2. The applied carrier material was palm fat. The products with different anthocyanin-carrier ratios were measured for their colour properties (lightness, hue angle, and saturation). Colour stability was monitored for prolonged storage at different conditions (light/dark and ambient temperature/ refrigerator). The obtained powderous anthocyanin-palm fat products showed good colour stability, which gives good bases for potential applications in the future.

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Enzyme-linked immunosorbent assays (ELISAs) are widely used to determine gluten contamination in gluten-free and low gluten food samples. ELISA assays developed using monoclonal antibodies against known toxic peptides have an advantage in the identification of toxic prolamin content in protein extracts of different food samples, as well as raw materials. R5 and G12 monoclonal antibodies specific for two known toxic peptides used in commercially available gluten ELISA assays were applied to test toxic peptide contents in wheat relatives and wild wheat species with different genome composition and complexity. Although the R5 peptide content showed some correlation with ploidy levels in Triticum species, there was a high variance among Aegilops species. Some of the analysed diploid Aegilops species showed extremely high R5 peptide contents. Based on the bioinformatics analyses, the R5 peptide was present in most of the sulphur rich prolamins in all the analysed species, whereas the G12 epitope was exclusively present in alpha gliadins. High variation was detected in the position and frequency of epitopes in sequences originating from the same species, thus highlighting the importance of genotypic variation within species. Identification of new prolamin alleles of wheat relatives and wild wheat species is of great importance in order to find germplasm for special end-use quality purposes as well as development of food with reduced toxicity.

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Agrokémia és Talajtan
Authors:
A. Horel
,
Zs. Bakacsi
,
M. Dencső
,
Cs. Farkas
,
Gy. Gelybó
,
I. Kása
,
E. Tóth
,
S. Molnár
, and
S. Koós

A vizsgálat 42 órája alatt (2016. február 3–4.) és az előtte lévő öt hónapban összesen négy nagyobb mennyiségű csapadékesemény történt a Csorsza-patak vízgyűjtő területén. A vizsgált esőzés időszakában 21,6 mm csapadékmennyiség hullott összesen a vízgyűjtő területére 5 órás intervallumban. A csapadékesemény első órájában a patak zavarosság értéke majdnem megduplázódott, viszont így is viszonylag alacsony szinten maradt a későbbiekben mért értékekhez viszonyítva. Az esőzés kezdetét követő 7. órában emelkedett meg jelentősen a zavarosság mértéke, több mint 14-szeresére, a 13–14. órában pedig 34-szeresére nőtt a vizsgálat előtti naphoz viszonyítva. A Csorsza-patak zavarosságának nagysága nem sokkal a tetőzést követően nagy mértékben lecsökkent, 13 órával később pedig hasonló értékeket mutatott, mint a vizsgálat előtti esőzés nélküli időszakban.

A nagyobb esőzések alkalmával az alacsonyabb területeken fekvő, minimális lejtésű szántó esetében telítettséghez közeli talajnedvesség-tartalom volt megfigyelhető, míg a legkisebb talajnedvesség-tartalom ingadozás az esőzést követően a gyepes és az erdős területekre volt jellemző.

A jelen vizsgálatban összegyűjtött adatok alapján a Csorsza-patakból a Balatonba bekerülő talajhordalék mennyisége a téli időszakban, az erozív esőzések gyakoriságának ismeretében könnyebben és pontosabban becsülhető. Annak érdekében, hogy az éves átlag lebegtetett hordalék mennyiségének a becslését pontosabban el tudjuk végezni, több időszakos mérésre volna szükség.

Munkánkat az OTKA K—101065 projekt, az OTKA PD—116157 és OTKA PD—116084 kutatási projekt, valamint a Bolyai János Kutatási Ösztöndíj támogatta. Külön köszönet Mózes Mariann és Bányász Ágnes részére a laboratóriumi vizsgálatokban nyújtott segítségükért, valamint Szegvári Győző és kollégáinak a zánkai vízminták gyűjtésében való hatalmas segítségükért.

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Acta Botanica Hungarica
Authors:
Cs. Molnár
,
Zs. Molnár
,
Z. Barina
,
N. Bauer
,
M. Biró
,
L. Bodonczi
,
A. Csathó
,
J. Csiky
,
J. Deák
,
G. Fekete
,
K. Harmos
,
A. Horváth
,
I. Isépy
,
M. Juhász
,
J. Kállayné Szerényi
,
G. Király
,
G. Magos
,
A. Máté
,
A. Mesterházy
,
A. Molnár
,
J. Nagy
,
M. Óvári
,
D. Purger
,
D. Schmidt
,
G. Sramkó
,
V. Szénási
,
F. Szmorad
,
Gy. Szollát
,
T. Tóth
,
T. Vidra
, and
V. Virók

The first version of the map of the Hungarian vegetation-based landscape regions were prepared at the scale of 1: 200,000 (1 km or higher resolution). The primary goal of the map was to provide an exact background for the presentation and evaluation of the data of the MÉTA database. Secondly, we intended to give an up-to-date and detailed vegetation-based division of Hungary with a comprehensive nomenclature of the regions. Regions were primarily defined on the basis of their present zonal vegetation, or their dominant extrazonal or edaphic vegetation. Where this was not possible, abiotic factors that influence the potential vegetation, the flora were taken into consideration, thus, political and economical factors were ignored. All region borders were defined by local expert botanists, mainly based on their field knowledge. The map differs in many features from the currently used, country-wide, flora-or geography-based divisions in many features. We consider our map to be temporary (i.e. a work map), and we plan to refine and improve it after 5 years of testing.

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