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Lindera obtusiloba Blume is the northernmost tree species in the family Lauraceae, and it is a key species in understanding the evolutionary history of this family. The species of L. obtusiloba in East Asia has diverged into the Northern and Southern populations, which are geographically separated by an arid belt. Though the morphological differences between populations have been observed and well documented, intraspecific variations at the plastomic level have not been systematically investigated to date. Here, ten chloroplast genomes of L. obtusiloba individuals were sequenced and analyzed along with three publicly available plastomes. Comparative plastomic analysis suggests that both the Northern and the Southern populations share similar overall structure, gene order, and GC content in their plastomes although the size of the plasome and the level of intraspecific variability do vary between the two populations. The Northern have relatively larger plastomes while the Southern population possesses higher intraspecific variability, which could be attributed to the complexity of the geological environments in the South. Phylogenomic analyses also support the split of the Northern and Southern clades among L. obtusiloba individuals. However, there is no obvious species boundary between var. obtusiloba and var. heterophylla in the Southern population, indicating that gene flow could still occur between these two varieties, and this could be used as a good example of reticulate evolution. It is also found that a few photosynthesis‐related genes are under positive selection, which is mainly related to the geological and environmental differences between the Northern and the Southern regions. Our results provide a reference for phylogenetic analysis within species and suggest that phylogenomic analyses with a sufficient number of nuclear and chloroplast genomic target loci from widely distributed individuals could provide a deeper understanding of the population evolution of the widespread species. [ABSTRACT FROM AUTHOR]

Humus layer has an important effect on the diversity and spatial distribution of microbes. However, the role of partitioning of humus layer microhabitats for soil microbial diversity has been poorly documented. In this study, 120 soil samples were collected from a 5‐ha forest dynamic monitoring sample plot in a deciduous broad‐leaved forest. Clustering analysis was used to delineate microhabitats by humus layer. We explored diversity and community composition of soil fungi and bacteria using Illumina sequencing of the ITS rRNA gene and 16S rRNA gene region on the MiSeq platform. We investigated the diversity, species composition, and the microhabitat preferences of fungi and bacteria and then analyzed the effects of environmental factors on soil fungi and bacteria. Our results showed that the diversity, species composition, and the indicator species of the fungal and bacterial community varied among different humus layer microhabitats. In network analysis, the specialization indexes showed that 16.20%/22.30% of the fungal/bacterial operational taxonomic units (OTUs) had the characteristics of distribution specialization for humus layer microhabitats. Mantel test showed that the main environmental drivers of fungi and bacteria were not consistent among the four microhabitats. Our findings indicated that the distribution of soil microbes among humus layer microhabitats is not random, but specialized. We furthermore found that there were differences in the relationship between soil microbes and environment among microhabitats defined by humus layer. Together, these findings suggest the importance of partitioning of humus layer microhabitats in maintaining local diversity in a soil microbial community. [ABSTRACT FROM AUTHOR]

Cortex Fraxini is an important traditional Chinese herbal medicine used for the treatment of gout and hyperuricemia. An efficient and rapid ultra-performance liquid chromatography mass spectrometry method was developed and validated for simultaneous quantitation of six coumarins (aesculin, fraxin, aesculetin, fraxetin, sopoletin and 7-hydroxycoumarin) in normal and hyperuricemic rats plasma after oral administration of Cortex Fraxini. The method could successfully be applied for pharmacokinetics studies. The pharmacokinetic behavior of six coumarins in normal and hyperuricemia rats plasma was determined. Results showed that, for some of analytes, the pharmacokinetic parameters (AUC0- t, AUC0-∞, Cmax, Tmax and CL) were significantly different between normal and hyperuricemic rats. The different pharmacokinetic parameters might result from renal impairment or a change of metabolic enzymes in the pathological state. The pharmacokinetic study in pathological state could provide more useful information to guide the clinical use of traditional Chinese herbal medicine. [ABSTRACT FROM AUTHOR]