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Lake Hévíz is the largest natural thermal lake of Europe, harboring special bacterial communities. The aim of the present study was to gain information about the distribution and species diversity of the sediment microbiota, with special focus on Actinobacteria, by using cultivation-based and -independent molecular methods. Samples from two depths were taken in two different locations in October 2007. 245 strains were isolated, grouped to 85 OTUs by ARDRA, and identified by 16S rDNA sequencing. Most of the strains showed highest sequence similarity with Bacillus and related genera. Strains belonging to the phylum Actinobacteria were identified as members of Arthrobacter, Brachybacterium, Brevibacterium, Curtobacterium, Friedmanniella, Gordonia, Kocuria, Microbacterium, Micrococcus, Micromonospora, Mycobacterium, Rhodococcus, Streptomyces and Williamsia . Two clone libraries were constructed from H3M and H4M samples, providing 288 and 192 clones which were grouped to 150 and 125 OTUs, respectively, by ARDRA. The two most abundant group of the H4M library were OP8-related. The phylum Proteobacteria was represented mostly by δ -Proteobacteria, other relevant groups were Cyanobacteria, Bacteroidetes, Acidobacteria and β -Proteobacteria. The H3M library was dominated by Cyanobacteria, Verrucomicrobia, β -Proteobacteria, γ -Proteobacteria and δ -Proteobacteria. Chloroflexi, Bacteroidetes, Spirochetes and Firmicutes were scarce. Results from the clone libraries were compared to the length-heterogeneity-PCR fingerprints of the communities.

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Abstract  

The multi-elemental content of sixteen glass beads and eight glass samples from archeological site Sg Mas in Bujang Valley (finding from 5 th to 14 th century) were assayed by neutron activation analysis (NAA). Ten beads differed in colour and eight of them were opaque. Contents of twentyfour elements, which might be present in the samples as a flux, stabilizer, colorants or opacifier were examined. The elements Al, Br, Cl, Co, Cr, Fe, Hf, K, Mn, Na, Sc,Th, Zn and Zr were detectable in all samples. On the other hand, concentration of the elements As, Ba, Ca, Cs, Rb, Sb, Ta, Ti, U, and V were below the detection limit in some samples. The concentration of elements found are discussed in terms of color and/or opacity of the glass bead and glass samples. Although the elemental composition does not fully explain the color and opacity of the studied materials, it can still be used as fingerprint of the glass used for the bead making.

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Genetic variation in the flint maize (Zea mays L. conv. indurata) gene pool has decreased significantly since the introduction of hybrid breeding into Europe in the 1950s, leading to greater genetic vulnerability. Landraces, stored in gene banks, offer a valuable source to broaden the genetic basis again. The objective of this study was the genetic characterization of 166 Swiss landrace accessions originating from 7 Swiss regions (alpine valleys). The material was fingerprinted using a set of ten SSRs (Simple Sequence Repeat Markers). The resulting cladogram showed three main clusters comprising 95, 22 and 49 accessions, respectively. The largest group of accessions, from the Rhine valley of St. Gallen (RT), was present in all three main clusters. However, the majority of RT accessions was found in the first main cluster, together with those from the western neighbouring region (Linthtal) and from the southwestern neighbouring region (Wallis). Those from Tessin (southern Switzerland) were found mainly in one sub-cluster within the third main cluster. This is a very encouraging first step in appraising the genetic differences among accessions from Swiss regions.

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Experiments were performed to study changes caused by irradiation or high hydrostatic pressure pasteurization of liquid egg white by differential scanning calorimetry, spectrofluorimetry, electronic nose measurements and NIR-spectrometry. The non-thermal pasteurization treatments were also assessed in relation to loss of carotenoid content, and lipid- and cholesterol oxidation of liquid egg yolk. Unlike radiation pasteurization, high pressure processing caused protein denaturation in egg white, which manifested in changes of its DSC-thermogram and intrinsic tryptophan fluorescence. Electronic nose testing showed changes of the head-space volatile composition of egg albumen, particularly as a function of radiation treatment. Both treatments caused changes in the NIR-spectrometric “fingerprint” of the liquid egg white. Various chemometric analyses of the results of the latter instrumental methods, particularly statistical techniques developed by the group of one of the co-authors of this article, demonstrated the potential for detection and characterization of the applied non-thermal processing techniques on liquid egg white. Irradiation induced more carotenoid degradation and lipid oxidation in liquid egg yolk than pressure processing.

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Acta Veterinaria Hungarica
Authors: László Makrai, Csaba Nemes, Anna Simon, Éva Ivanics, Zoltán Dudás, László Fodor, and Róbert Glávits

Enterococcus cecorum is the most frequently occurring enterococcal species in the intestine of chickens of over 12 weeks of age, and there are few reports on its isolation from the skeleton of broiler parent chicks. In the present study, observations on vertebral osteomyelitis and spondylolisthesis (‘kinky back syndrome’) showing high incidence in 8 broiler parent flocks in different parts of Hungary are summarised. Clinical signs were seen only in roosters between 5 and 13 weeks of age. Diseased birds were alert and remained sitting on their hocks with their feet slightly raised off the ground. Incidence of the disease among male birds ranged from 8% to 30% depending on flocks. Enlargement and distortion of the body of the 6th vertebra were seen as the main pathological lesions. The cavity of the spinal canal was constricted by the distorted vertebral bodies. Resorption of bone tissue and sequestrum formation, signs of increased osteoclast activity, proliferation of fibrotic tissues, infiltration with heterophils and formation of sclerotic layers were detected in the vertebral bodies. From all 24 samples collected from the vertebral lesions, Enterococcus cecorum was isolated and identified using metabolic fingerprinting as well as 16S rRNA gene sequencing. Demonstration of E. cecorum from the vertebral lesions in all examined broiler breeder roosters showing the same clinical and pathological findings in different flocks suggested the pathogenic role of this microorganism for the first time in Hungary.

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A rapid and reliable HPTLC method for analysis of aristolochic acids (AA) has been developed on the basis of a TLC procedure previously published by the German Drug Codex (DAC). The new method enables visual detection of the acids with certainty at very low levels (400 pg absolute of aristolochic acid A) in plant material and can therefore be used for screening Chinese drugs to ensure their safety on the basis of the absence of AA. Qualitatively Stephania tetrandra can be distinguished from various Aristolochia spp., Asarum spp. , and other drugs with similar Chinese names, on the basis of fingerprints.At least five different aristolochic acids can be detected in Aristolochia spp. The method is very specific and sensitive and is suitable for establishing and documenting adulteration of Stephania raw material with less than 1% Aristolochia fangji . By use of scanning densitometry quantitative determination of AA can be performed at low concentrations (1 ppm). Validation data (ICH) including linearity, limit of detection, precision, and accuracy are presented. The performance of the method is discussed on the basis of comparison with an HPLC-MS method proposed by the US FDA. HPTLC analysis is presented as a very useful complementary technique to the more sophisticated procedures used in legal cases.

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This study was designed to develop a simple, sensitive, selective, and precise high-performance thin-layer chromatography (HPTLC) fingerprint and quantitative estimation method for the analysis of three phenolic compounds from nine Leucas species. The developed HPTLC method was validated according to the International Conference on Harmonization guidelines. The method permits reliable quantification of one important phenolic acid (gallic acid) and two hydroxycinnamic acids (caffeic and ferulic acids) in 50% hydroethanolic extracts on silica gel with toluene—ethyl acetate—formic acid 8:2:1 (v/v) as the mobile phase. The system showed good resolution and separation of caffeic, ferulic, and gallic acids (at R f values 0.48, 0.60, and 0.30, respectively) from the other constituents of the extract. Densitometric scanning was done at 300 nm in absorbance mode. All the results obtained by the developed method were statistically compared for validation parameters, for accuracy and good precision. Caffeic, ferulic, and gallic acids were estimated in all the aforesaid nine Leucas species, but the quantity varied from species to species. Further, these phenolics were reported from the aforesaid Leucas species for the first time, except for Leucas lanata and Leucas urticifolia. However, Leucas biflora, Leucas decemdentata, and Leucas stricta were documented for their chemical constituents for the first time. The proposed HPTLC method can be used for routine quality testing of Leucas species.

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Summary

A simple and rapid method, using online ultraperformance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry (UPLC-PDA-eλ-ESI-MS/MS), was developed for the in-depth analysis of 50 batches Radix et Rhizoma Rhei. The analysis was performed on a UPLC BEH C18 column using a gradient elution system. Baseline separation could be achieved in less than 7.5 min. At the same time, on the basis of the 50 batches of samples collected from representative cultivated regions, a novel chromatographic fingerprint was devised by UPLC-PDA, in which 27 common peaks were detected and identified by the developed UPLC-MS/MS method step by step according to fragmentation mechanisms, MS/MS data, standards, and relevant literature. Many active components gave prominent [M - H] ions in the ESI mass spectra. These components include anthraquinones, sennosides, stilbenes, glucose gallates, naphthalenes, and catechins. Furthermore, based on the information of these Radix et Rhizoma Rhei components, and further combined with discriminant analysis, a novel discriminant analysis equation (DAE) was established for the quality control of Radix et Rhizoma Rhei for the first time.

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To evaluate the quality of Fructus Arctii, an accurate and reliable method of high-performance liquid chromatography/diode array detection—electrospray ionization—mass spectrometry (HPLC/DAD—ESI—MS) was developed. Nine compounds, including chlorogenic acid, caffeic acid, trans-p-hydroxycinnamic acid, arctiin, arctignan A, ethyl caffeate, matairesinol, arctigenin, and lappaol B, were determined simultaneously in 19 batches of Fructus Arctii samples collected from different localities. Nineteen common peaks were identified or tentatively assigned by comparing their mass spectrometric data with reference compounds, self-established compound library, and published literatures. Also, the 19 common peaks were selected as characteristic peaks to assess the similarity of chromatographic fingerprinting of these samples. Moreover, hierarchical clustering analysis (HCA) and principal components analysis (PCA) were successfully applied to demonstrate the variability of samples. The results indicated the content of nine compounds that varied greatly among the samples, and 19 samples collected from different localities could be discriminated. Furthermore, chlorogenic acid, arctiin, and arctigenin were found to be chemical markers for evaluating the quality of Fructus Arctii.

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A simple, rapid, and precise high-performance thin-layer chromatographic method has been established for quantitative analysis of myricetin in the stem bark of Myrica esculenta, family Myricaceae. The marker myricetin was separated from other components of stem bark extract on silica gel 60 F254 HPTLC plates with toluene-ethyl acetate-formic acid-methanol 3:3:0.6:0.4 (v/v) as mobile phase. Densitometry in absorbance-reflection mode at 268 nm was used for quantitative analysis of myricetin. The stem bark of M. esculenta was found to contain 0.225% (w/w) myricetin. The method was validated for linearity, accuracy, precision, and specificity in accordance with ICH guidelines. The calibration plot was linear between 0.4 and 2.0 μg per band for myricetin. The limits of detection and quantitation were 0.0939 and 0.2845 μg per band, respectively. The method can be used as a quality control-method for fingerprint profiling and quantitative analysis of the stem bark of Myrica esculenta.

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