Jiuxiang Xie

Rodents’ lifestyles vary in different environments, and to adapt to various lifestyles specific digestion strategies have been developed. Among these strategies, the morphology of the digestive tracts and the gut microbiota are considered to play the most important roles in such adaptations. However, how subterranean rodents adapt to extreme environments through regulating gut microbial diversity and morphology of the digestive tract has yet to be fully studied. Here, we conducted the comparisons of the gastrointestinal morphology, food intake, food assimilation, food digestibility and gut microbiota of plateau zokor Eospalax baileyi in Qinghai-Tibet Plateau and laboratory rats Rattus norvegicus to further understand the survival strategy in a typical subterranean rodent species endemic to the Qinghai-Tibet Plateau. Our results revealed that plateau zokor evolved an efficient foraging strategy with low food intake, high food digestibility, and ultimately achieved a similar amount of food assimilation to laboratory rats. The length and weight of the digestive tract of the plateau zokor was significantly higher than the laboratory rat. Particularly, the weight and length of the large intestine and cecum in plateau zokor is three times greater than that of the laboratory rat. Microbiome analysis showed that genus (i.e., Prevotella, Oscillospira, CF231, Ruminococcus and Bacteroides), which are usually associated with cellulose degradation, were significantly enriched in laboratory rats, compared to plateau zokor. However, prediction of metagenomic function revealed that both plateau zokor and laboratory rats shared the same functions in carbohydrate metabolism and energy metabolism. The higher digestibility of crude fiber in plateau zokor was mainly driven by the sizes of cecum and cecum tract, as well as those gut microbiota which associated with cellulose degradation. Altogether, our results highlight that both gut microbiota and the morphology of the digestive tract are vital to the digestion in wild rodents.

The Datong yak (Bos grunniens) is the first artificial breed of yaks in the world and has played an important role in the improvement of domestic yak quality on the Qinghai-Tibet Plateau. The Datong yak breeding farm in the Qinghai province of China is the main place for the breeding and feeding of Datong yaks. It hosts domestic Datong yaks and wild male yaks, mainly in mixed groups. Different managements have different effects on livestock. The gut microbiota is closely related to the health and immunity of Datong yaks, and mixed grouping can affect the composition and diversity of the gut microbiota of Datong yaks. To reveal the effects of mixed grouping on the gut microbiota of Datong yaks and wild yaks and identify the main dominant factors, we compared the gut microbial diversities of domestic males and females and wild males based on 16S rRNA V3–V4 regions using fresh fecal samples. The data showed significant differences in the gut microbial diversity of these three groups, and the α-diversity was the highest in wild males. Different factors influence the gut microbiota, and the main influencing factors were different in different groups, including sex differences, host genetics, and physical interactions. We also compared ecological assembly processes in the three groups. The results showed that mixed grouping contributed to the improvement of gut microbial diversity in domestic females. Our study provides effective and feasible suggestions for the feeding and management of the Datong yaks.

The complete mitochondrial genome of Syrphus vitripennis was sequenced and reported here. The circle genome of S. vitripennis is 16,185 bp in length. There are 38 sequence elements including 13 protein coding genes, 22 tRNA genes, 2 rRNA genes, and a control region. The order of all elements was the same with that of Eristalia cerealis. With two species from Muscidae and Drosophilidae as outgroups, phylogenetic relationships of eight Syrphidae species based on mitogenomes were in complete agreement with their taxonomic relationships based on morphological characteristics. Our result will provide more fundamental data to the development of the molecular systematics of Syrphidae.

The complete mitochondrial genome of Melanostoma scalare was sequenced and reported here. The circle genome of the syrphid fly is 16,380 bp in length. There are 38 sequence elements including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region. The order of all elements was the same with that of Eristalia cerealis. With 2 species from Muscidae and Drosophilidae as outgroups, phylogenetic relationships of 8 Syrphidae species based on mitogenomes were in complete agreement with their taxonomic relationships based on morphological characteristics. Our result will provide more fundamental data to the development of the molecular systematics of Syrphidae.

In this work, an efficient method for the rapid extraction and separation of antioxidant phenols was developed and optimized. The method was then applied to extract and separate nine phenols from 37 varieties of raspberry, in which their antioxidant activities were further investigated. First, the extraction was conducted using ultra-sonication, which was then further separated using reversed-phase high-performance liquid chromatography/ultraviolet (RP-HPLC/UV) analysis. In this step, several key parameters (volume of the extraction reagent, time of extraction, and the temperature of extraction) affecting its efficiency were investigated and optimized using the response surface methodology (RSM) combined with the Box–Behnken design (BBD) so that the optimal conditions were obtained. According to the overall results of the optimization study, the optimal conditions were chosen as follows: volume of extraction reagent = 2.0 mL, time of extraction = 50.0 min, and temperature of extraction = 50 °C. The optimal conditions were then applied to extract nine phenols, including gallic acid, catechin, chlorogenic acid, vanillic acid, syringic acid, cumaric acid, ferulic acid, rosemary acid, and quercetin from 37 raspberry varieties. The extracted phenols were characterized and their antioxidant activities, including DPPH⁻ and ABTS⁻ free radical scavenging and intracellular reactive oxygen species (ROS) activity, using HepG2 cells as the model, were subsequently studied. The findings suggested that although their contents varied among most raspberry varieties, these phenols significantly contributed toward their antioxidant capacity and scavenging intracellular ROS activities. This study provides a scientific and theoretical basis for the selection of raspberry varieties and product development in Qinghai province.

Eustoma grandiflorum (Raf.) Shinners is a popular cut flower due to its beautiful morphological characteristics and extended vase life. Here, the complete plastome sequence of E. grandiflorum was reported based on the Illumina HiSeq Platform. The plastome sequence is 154,230 bp in length with a typical quadripartite structure, containing a pair of inverted repeated (IR) regions (25,755 bp) that are separated by a large single copy (LSC) region of 84,297 bp, and a small single copy (SSC) region of 18,423 bp. A total of 130 functional genes were annotated, including 84 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. The complete plastome sequence of E. grandiflorum will provide a valuable resource for its garden utilization and the phylogenetic studies of Gentianaceae.