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Acta Biologica Hungarica
Authors:
B. Morgun
,
A. Richter
,
D. Deshmukh
,
V. Stepanyuk
,
Katalin Kálai
,
G. Nagy
,
L. Hufnagel
, and
Noémi Lukács

Expression of antibodies or antibody fragments in plants is a useful tool for producing active antibody derivatives for diagnostic or pharmaceutical purposes as well as for immunomodulation. We investigated the effect of cellular expression site on the stability and yield of double-stranded RNA (dsRNA)-specific single-chain Fv-fragments (scFv) in transgenic tobacco. Two antibodies (J2 and P6) belonging to the V23(J558) heavy chain variable gene family but differing in the light chain variable domain were used. scFvs were targeted to the cytoplasm - with or without anchoring them in the plasma membrane -, into the endoplasmic reticulum (ER) and to the apoplast. Although high mRNA concentrations were detected in all cases, scFv proteins accumulated only when scFvs were made ER-resident by appropriate signal sequences. When the ER retention signal was removed to allow scFv-secretion to the apoplast, no scFv-proteins were detected. Despite the strong homology of the VH-sequences of J2 and P6 antibodies, only P6 provided a stable scFv scaffold for intracytoplasmic expression. J2-scFv could not be stabilised either by adding a C-terminal stabilisation signal or by anchoring the protein on the cytoplasmic side of the plasma membrane (PM). It was found that dsRNA-specific J2-scFvs are active in vivo and enhance Potato Virus Y induced symptoms in infected tobacco. This is the first report describing the expression and biological effect of RNA-specific antibodies in plants.

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Frozen fillets of Atlantic herrings (Clupea harengus) were used to evaluate the effect of glaze with or without addition of selected herbal extracts on lipid oxidation and sensory properties during 8 months of freezing storage under −14 °C. Fillets were divided into four groups: control non-glazed group, glazed group without addition of herbal extracts, and glazed groups with addition of hawthorn (Crataegus oxyacantha L.) extract (0.3%) and agrimony (Agrimonia eupatoria L.) extract (0.3%). The antioxidant activity and total phenolic content in hawthorn and agrimony extracts, and their effect on lipid deterioration expressed as thiobarbituric acid reactive substances were measured. The results showed that the herbal extracts of hawthorn and agrimony are effective antioxidants and good sources of total phenols. Significant influence of herbal extracts added into glaze on the extent of lipid oxidation changes has been obvious within 4 months storage of herring fillets under freezing conditions. Finally, positive influence of glaze and herbal extracts on organoleptic characteristics of fish fillets was found.

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Acta Phytopathologica et Entomologica Hungarica
Authors:
M. Tóth
,
A. Nagy
,
I. Szarukán
,
K. Ary
,
A. Cserenyec
,
B. Fenyődi
,
D. Gombás
,
T. Lajkó
,
L. Merva
,
J. Szabó
,
P. Winkler
, and
J. K. Jósvai

The addition of synthetic (E)-anethol to the known attractant phenylacetaldehyde synergized attraction of the cotton bollworm Helicoverpa armigera, the blend invariably catching 4 to 6 times more than phenylacetaldehyde on its own. Highest catches were recorded by the 1:1-3:1 blends. The addition of salicyl aldehyde, ±linalool, (R)-(+)-limonene, 2-methoxybenzyl alcohol and 4-methoxybenzyl alcohol (compounds described earlier in the literature as co-attractants for H. armigera), increased catches when added to phenylacetaldehyde. However, the addition of these compounds did not increase catches of the (E)-anethol+pheny- lacetaldehyde blend. When directly compared with performance of the synthetic pheromone, the (E)-anethol +phenylacetaldehyde blend caught an average of 27% of the catch in pheromone baited traps. On an average 79% of moths caught in traps with the (E)-anethol+phenylacetaldehyde blend were females, while traps with pheromone caught only males. The (E)-anethol+phenylacetaldehyde blend described in this study may form the basis for the development of an efficient bisexual lure for H. armigera AFTER further optimization.

Open access
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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