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1.
PLoS One ; 18(4): e0283847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37043495

RESUMO

This is the first study to systematically evaluate rRNA secondary structures of Hedysareae with an emphasis on Hedysarum. ITS2 and 5.8S regions of the genus shared a common secondary structure with a four-fingered central loop, whereas ITS1 possessed five distinct structures. The secondary structural features of the two regions provided advantageous data for clades, species groups, and closely related species. Hemi-CBCs were mostly observed in the reconstruction of species groups, and Nsts, mostly between closely related species. The investigations showed that ITS1 varied more than ITS2 in length, GC content, and most of the diversity indices within the tribe. Maximum likelihood analyses of the synchronized sequence-structure tree of ITS1 were performed. The accuracy and phylogenetic signals of ITS1 were higher than ITS2. The similar GC content, and no CBC, in both spacers, fortified the close relationship of CEGO and H. sections Stracheya and Hedysarum clades in the synchronized sequence-structure tree topology of ITS1. In both regions, no inter-generic CBCs were detected inside the CEGO clade and the inter-sectional level of Hedysarum. But, in the ITS2 region, a CBC was detected between H. section Multicaulia, and Taverniera versus H. sections Hedysarum, and Stracheya. The lowest inter-sectional genetic distance and structural features were found between H. sect. Hedysarum and H. sect. Stracheya clades in the ITS2 region.


Assuntos
Fabaceae , Fabaceae/genética , Filogenia , DNA Espaçador Ribossômico/genética , Verduras/genética , RNA Ribossômico
2.
Alp Bot ; 131(2): 177-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721248

RESUMO

Alpine habitats are characterized by a high rate of range restricted species compared to those of lower elevations. This is also the case for the Irano-Anatolian global biodiversity hotspot in South-West Asia, which is a mountainous area harbouring a high amount of endemic species. Using two quantitative approaches, Endemicity Analysis and Network-Clustering, we want to identify areas of concordant species distribution patterns in the alpine zone of this region as well as to test the hypothesis that, given the high proportion of endemics among alpine species, delimitation of these areas is determined mainly by endemic alpine species, i.e., areas of concordant species distribution patterns are congruent with areas of endemism. Endemicity Analysis identified six areas of concordant species distribution patterns irrespective of dataset (total alpine species versus endemic alpine species), whereas the Network-Clustering approach identified five and four Bioregions from total alpine species and endemic alpine species, respectively. Most of these areas have been previously identified using the endemic flora of different elevational zones. The identified units using both methods and both datasets are strongly congruent, proposing that they reveal meaningful distribution patterns. Bioregionalization in the Irano-Anatolian biodiversity hotspot appears to be strongly influenced by the endemic alpine species, a pattern likely to hold in alpine regions outside the Irano-Anatolian hotspot. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00035-021-00266-7.

3.
Biomed Chromatogr ; 33(9): e4572, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062369

RESUMO

A simple method, air-assisted dispersive micro-solid-phase extraction-based supramolecular solvent was developed for the preconcentration of tramadol in biological samples prior to gas chromatography-flame ionization detection. A new type of carrier liquid, supramolecular solvent based on a mixture of 1-dodecanol and tetrahydrofuran was combined with layered double hydroxide coated on a magnetic nanoparticle (Fe3 O4 @SiO2 @Cu-Fe-LDH). The supramolecular solvent was injected into the solution containing Fe3 O4 @SiO2 @Cu-Fe-LDH in order to provide high stability and dispersion of the sorbent without any stabilizer agent. Air assisted was applied to enhance the dispersion of the sorbent and solvent. A number of analytical techniques such as Fourier transform-infrared spectrometry, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray diffraction measurements were applied to assess the surface chemical characteristics of Fe3 O4 @SiO2 @Cu-Fe-LDH nanoparticles. The effects of important parameters on the extraction recovery were also investigated. Under optimized conditions, the limits of detection and quantification were obtained in the range of 0.9-2.4 and 2.7-7.5 µg L-1 with preconcentration factors in the range of 450-472 in biological samples. This method was used for the determination of tramadol in biological samples (plasma, urine and saliva samples) with good recoveries.


Assuntos
Nanopartículas de Magnetita/química , Microextração em Fase Sólida/métodos , Tramadol/análise , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Saliva/química , Solventes/química
4.
Ultrason Sonochem ; 50: 182-187, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30287181

RESUMO

In this work, an ultrasonic-assisted supramolecular based on solidification of floating organic drop microextraction (UA-SM-SFO-ME) was developed as a green method for preconcentration of methadone prior to gas chromatography-mass spectrometry (GC-MS). The supramolecular solvent aggregates containing reverse micelles of 1-dodecanol in tetrahydrofuran (THF) were formed by ultrasonication that subsequently dispersed in the sample solution. Ultrasonic waves caused the fast formation of supramolecular solvent aggregates. In this work, ultrasonication was used in two phases: First phase, the formation of reverse micelles and the second phase, the dispersion of supramolecular solvent in the sample solution. Actually, ultrasonication was basic of this presented work. In order to provide the highest extraction efficiency, the influence of various parameters on the method performance (supramolecular solvent type and volume, disperser solvent condition, pH, extraction time and salt concentration) was investigated. Based on the obtained optimum conditions, the limits of detection (LODs) and the limits of quantitation (LOQs) were obtained 0.5-1.2 µg L-1 and 1.2-2.5 µg L-1 with preconcentration factors in the range of 182-191, in water and biological samples, respectively. Subsequently, the method was assessed for preconcentration of the methadone in human plasma and saliva samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Metadona/análise , Metadona/sangue , Compostos Orgânicos/química , Saliva/química , Ondas Ultrassônicas , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Micelas , Reprodutibilidade dos Testes , Solventes/química
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