Selenium (Se) is an essential trace element for humans and has conveyed great a wide range of interests due to its contribution to health. Presently, the regulatory mechanisms of selenium on human health, especially the regulatory mechanisms of selenium on human intestinal (gut) microflora and its effects on diseases are receiving attention from academic circles. This review involves the effects of selenium on physical health, the relationship between selenium and intestinal microflora, and the progress of research between selenium, intestinal microflora, and diseases. Furthermore, the current status of research on the selenium, intestinal microflora, and diseases is also presented.

Stellera chamaejasme (S. chamaejasme) is an important medicinal plant with heat-clearing, detoxifying, swelling and anti-inflammatory effects. At the same time, it is also one of the iconic plants of natural grassland degradation in northwest China, playing a key role in the invasion process. Plant endophytes live in healthy plant tissues and can synthesize substances needed for plant growth, induce disease resistance in host plants, and enhance plant resistance to environmental stress. Therefore, studying the root endophytes of S. chamaejasme is of great significance for mining beneficial microbial resources and biological prevention and control of S. chamaejasme. This study used Illumina MiSeq high-throughput sequencing technology to analyze the composition and diversity of endophytes in the roots of S. chamaejasme in different alpine grasslands (BGC, NMC and XGYZ) in Tibet. Research results show that the main phylum of endophytic fungi in the roots of S. chamaejasme in different regions is Ascomycota, and the main phyla of endophytic bacteria are Actinobacteria, Proteobacteria and Firmicutes (Bacteroidota). Overall, the endophyte diversity of the NMC samples was significantly higher than that of the other two sample sites. Principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA) results showed significant differences in the composition of endophytic bacterial and fungal communities among BGC, NMC and XGYZ samples. Co-occurrence network analysis of endophytes showed that there were positive correlations between fungi and some negative correlations between bacteria, and the co-occurrence network of bacteria was more complex than that of fungi. In short, this study provides a vital reference for further exploring and utilizing the endophyte resources of S. chamaejasme and an in-depth understanding of the ecological functions of S. chamaejasme endophytes.

Efficient extraction of Li from brine at a low cost is becoming a key technology to solve energy and environmental problems. Electrochemical extraction of Li has become a research hotspot due to its low energy consumption, high selectivity, and environmental friendliness. LiMn₂O₄, LiFePO₄, and LiNi_1/3Co_1/3Mn_1/3O₂ are widely used as cathode materials for the electrochemical extraction of Li but they also have some drawbacks, such as a small adsorption capacity. In this paper, the principle of electrochemical Li extraction from brine is reviewed and the research progress and analysis of the above three working electrode materials is summarized. In addition, analysis of the extraction of other rare ions from the working electrode material and the effect of micro-organisms on the working electrode material is also presented. Next, the shortcomings of working electrode materials are expounded upon and the research direction of working electrode materials in electrochemical Li extraction technology are prospected. It is hoped that this paper can provide insights and guidance for the research and application of electrochemical Li extraction from brine.

As the phosphorus (P) availability limits nutrient uptake and yield of crop plants, there is an urgent need to explore more P-solubilizing microorganisms and the influencing factors of their abundance in the field. However, it remains unclear how environmental and plant-related factors affect both total bacterial community and P-solubilizing bacteria in various P regime. In this study, we characterized the rhizosphere bacterial communities of Tibetan barley at 29 sites (classified into four soil types with varying AP contents) in a field survey as well as different barley origins in a field control experiment (located in Lasa and Linzhi) in China. We identified the P-solubilizing capacity of isolated bacterial strains in vitro and explored their distribution and relative abundance in the bacterial communities of Tibetan barley plants across sites and soil types. Our results found that Bacillus and Pseudomonas bacteria with the P-solubilizing capacity could be widely distributed in the rhizosphere of barley plants at different sites. Relative abundance of P-solubilizing bacteria and bacterial community structure, including the relative abundance of both dominant phyla and genera, OTUs richness, and Shannon index, varied greatly among the four soil types and was also related with soil available P content. These parameters were only affected by experimental location rather than plant seed origin, mainly due to a stronger influence of soil conditions in shaping root-associated bacterial community compared to plant-related factors. Overall, our study highlights the necessity of combining field survey and experimental approaches to explore the underlying mechanisms of plant-soil microorganism interactions.