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Their increasing commercial availability and their rather high total arsenic contents necessitate a more detailed arsenic speciation analysis of marine algal products. Compared to current HPLC-ICPMS methods, HPLC on-line with electrospray tandem mass spectrometry in the selected reaction monitoring mode (HPLC-ES-SRM) offers much higher detection selectivity with similarly high sensitivity for most known organoarsenic species. This study demonstrates the advantages of HPLC-ES-SRM for the detection of the main as well as trace arsenic species in extracts of 12 commercially available marine algal powders. The main focus was the unambiguous identification of the detected arsenic species. Four quality control tools were applied for this purpose, including matching chromatographic retention times, comparing SRM transition ratios, recording product ion spectra, and determining accurate masses. As a result, evidence was obtained for the presence of 19 organoarsenic species in the analyzed algal extracts. The method of standard addition was used for quantification. Estimated matrix effects on the analyte signal were similar for most of the investigated arsenic species in extracts of different types of brown algae. This allowed the comparison of the contents of the arsenic species present in the 12 algal extracts on the basis of normalized peak areas. A partial correlation of the arsenic speciation pattern with the algal family or algal order, respectively, was found. 相似文献
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Stefania Dooms Spiros Papakostas Stefan Hoffman Daan Delbare Alexander Triantafyllidis Olav Vadstein Patrick Sorgeloos 《Aquaculture (Amsterdam, Netherlands)》2007,262(1):29-40
Many zooplanktonic organisms, like the cyclic parthenogenetic rotifer Brachionus plicatilis (Rotifera: Monogononta), are actually a complex of species and biotypes with a high degree of morphological similarity (i.e. cryptic species). Various phylogenetic studies with molecular markers (e.g. ITS1 and COI) on wild Brachionus populations described the presence of at least nine genetically divergent Brachionus species and biotypes. Because different studies found evidence that these cryptic species and biotypes differ significantly in ecological preferences and thus probably behave differently in response to rearing conditions in the hatchery, questions rise on the actual identity of the rotifer strains used in aquaculture, where Brachionus discrimination is still based on morphology. This study is a part of an investigation of the genetic make-up of strains used in hatcheries, aquaculture research institutes and laboratories, and describes the rapid and sensitive PCR-DGGE method for the detection of Brachionus species and biotypes based on nucleotide sequence variation within the mitochondrial 16S rRNA gene. Considerable genetic diversity was found, albeit smaller within hatcheries than within laboratories and aquaculture research institutes. All 16S haplotypes produced an unambiguous DGGE fingerprint out of which a database was constructed. 相似文献
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Spiros A. Petropoulos Dimitra Daferera Moschos G. Polissiou Harold C. Passam 《植物养料与土壤学杂志》2009,172(2):210-215
The effect of four levels of nitrogen (N) application (3.2, 16.2, 32.4, and 48.6 g m–2) on the biomass and concentration and composition of essential oils of three parsley types (plain leaf, turnip‐rooted, curl leaf) was investigated in order to determine the optimum N level for oil production by this crop. The concentration of essential oils in the roots and leaves of plain leaf parsley and turnip‐rooted parsley was not affected by N application, but decreased with increasing N rate in curl leaf parsley. However, because the mean foliage biomass for all three types was about 2.5 times higher at 16.2 g m–2 N than in the low‐N‐rate treatment, the mean foliar oil yield increased from 0.68 to 1.38 g m–2. Root biomass increased by a factor of 1.7 at 16.2 g m–2 N (compared to the low‐N‐rate treatment), but oil yield increased only marginally from 0.3 to 0.4 g m–2. The composition of the essential oils of roots and leaves differed between parsley types. Increasing N application caused a reduction in the percentage of β‐phellandrene in the essential oils of parsley leaves. In turnip‐rooted parsley, increasing N caused a reduction in the percentage of myristicin and apiole. Because these three components of the essential oils contribute to parsley aroma, it may be concluded that although application of N fertilizer leads to higher parsley biomass and oil yield per plant, the essential oil components may change and aroma quality may be affected negatively. 相似文献
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Abimannan Arulkumar Alagusundaram Balamurugan Palanivel Rameshthangam Spiros Paramithiotis 《Journal Of Aquatic Food Product Technology》2017,26(8):929-939
The aim of the present study was to assess the physicochemical and microbiological changes during sun drying of salted wolf herring (Chirocentrus dorab) and coastal trevally (Carangoides coeruleopinnatus). For that purpose, the pH value, moisture, sodium chloride (NaCl) content, total volatile base nitrogen (TVB-N), histamine, cadaverine, putrescine, tryptamine, tyramine, spermine, and spermidine, as well as total aerobic mesophilic count, amine forming bacteria, total coliforms, Staphylococcus spp., and Bacillus spp., were determined. The initial pH value was 6.4 and increased during the salt drying process to 6.9 in both cases. The initial moisture, salt, and TVB-N levels of C. dorab and C. coeruleopinnatus were 64.3 and 60.3%, 2.55 and 2.70%, and 22.8 and 16.2 mg/100 g, respectively. At the end of drying, moisture decreased to 31.3 and 35.6%, respectively; salt increased to 13.71 and 16.04%; and TVB-N increased to 35.9 and 33.13 mg/100 g, respectively. Regarding total aerobic mesophilic count, amine forming bacteria, total coliforms, Staphylococcus spp., and Bacillus spp., a statistically significant (P < 0.05) reduction of the population was observed in both cases. Regarding the biogenic amine forming bacteria, Morganella morganii and Klebsiella pneumoniae were isolated from C. dorab; Bacillus cereus, Staphylococcus xylosus, and Providencia rettgeri were isolated from C. coeruleopinnatus. During sun drying, the amount of histamine, cadaverine, putrescine, and tryptamine was reduced; spermine was detected in C. dorab only during the first day, whereas spermidine was not detected. This reduction may be attributed to the presence of biogenic amine decomposing bacteria. However, further research is necessary in order to verify in situ this capacity and exploit potential applications for fish and fishery products. 相似文献
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Aristotelis C. Papageorgiou Amaryllis Vidalis Oliver Gailing Ioannis Tsiripidis Seraphim Hatziskakis Stefanos Boutsios Spiros Galatsidas Reiner Finkeldey 《European Journal of Forest Research》2008,127(1):81-88
The recent taxonomic classification of beech in Europe considers existence of one species (Fagus sylvatica L.) with two subspecies: F. sylvatica ssp. sylvatica and F. sylvatica ssp. orientalis. Four beech populations growing on the Greek part of the Rodopi Mountains were studied using morphological traits as well
as DNA molecular markers (AFLPs and chloroplast DNA SSR). The aim of the study was to describe the variation patterns of beech
in the Rodopi Mountains and to test the hypothesis of possible introgression between the beech subspecies’ sylvatica and orientalis in this area. Both morphological traits and gene markers revealed a possible influence of F. orientalis on the east side of Rodopi and at the low elevations, while characters resembling F. sylvatica were observed mainly on the western part of the mountains and in higher altitudes. There was a clinal increase of genetic
diversity from the west to the east, reaching a level firstly reported for beech populations. These results can be explained
either by the existence of a main refugial area for beech during the last glaciation or by the occurrence of a recent hybridization
among the subspecies, which were spatially isolated during the last glaciation and came into reproductive contact during their
postglacial remigration. These two scenarios are not necessarily mutually exclusive. 相似文献
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Serafeim C. Chaintoutis Chrysostomos I. Dovas Maria Papanastassopoulou Sandra Gewehr Kostas Danis Cécile Beck Sylvie Lecollinet Vasilis Antalis Stella Kalaitzopoulou Takis Panagiotopoulos Spiros Mourelatos Stéphan Zientara Orestis Papadopoulos 《Comparative immunology, microbiology and infectious diseases》2014
In the summer of 2010 an epidemic of West Nile virus (WNV) occurred in Central Macedonia, Greece, with 197 human neuroinvasive disease (WNND) cases. In the following years the virus spread to new areas, with a total of 76 WNND cases in 2011, and 109 WNND cases in 2012 (14 and 12 WNND cases, respectively, in Central Macedonia). We established a surveillance system based on serological testing of domestic pigeons, using cELISA confirmed by serum neutralization test. In Central Macedonia, pigeon seroprevalence was 54% (95% CI: 49–59%) and 31% (95% CI: 24–37%) at the end of the 2010 and 2011 epidemic seasons, respectively. One serum was positive for neutralizing antibodies directed against Usutu virus. Pigeon WNV seroprevalence and incidence rates of human WNND after the 2010 epidemic were positively correlated (ρ = 0.94, at the regional unit level), while in 2011 the correlation (ρ = 0.56) was not statistically significant, possibly due to small number of human WNND cases recorded. To evaluate the efficacy of the system at alerting upon WNV enzootic circulation before the onset of human cases, we tested 270 pigeons in 2011 and 240 pigeons in 2012. In Central Macedonia, the first seroconversions in pigeons were recorded 44 and 47 days, respectively, before the first human WNND cases. Pigeon surveillance was used successfully for identification of areas with WNV enzootic transmission and for early warning. Timely diffusion of information to health authorities facilitated the implementation of preparedness plans to protect public health. 相似文献
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