The cytochrome p450 gene family is widely involved in various biological processes in arthropods. Tick p450s are often associated with chemical acaricides, but knowledge of their involvement in the metabolism of plant-derived essential oil components is limited. In this study, we identified the non-redundant number of p450 transcripts (NRNPTs) from Haemaphysalis longicornis and Hyalomma asiaticum under the Cymbopogon citratus essential oil (CCEO) and terpinolene stress using de novo transcriptome data, respectively. In this study, we identified and characterized the NRNPTs of Ha. longicornis and Hy. asiaticum. Their gene expression patterns and biological functions under CCEO and terpinolene stress were further analyzed. Finally, Hy. asiaticum NRNPTs (87) were more numerous than Ha. longicornis (58). Phylogenetic analyses showed that NRNPTs of both Hy. asiaticum and Ha. longicornis could be categorized in clan 2, clan 3, clan 4, and clan mito, this data comes from the NRNPTs. Phylogenetic analyses showed that NRNPTs of both Hy. asiaticum and Ha. longicornis could be categorized in clan 2, clan 3, clan 4, and clan mito. p450 members of both were most distributed in clan 3. In addition, one Hy. asiaticum NRNPT was identified as belonging to the new classification clan 20 (HyasCYP20A1). The biological functions and pathways of p450 family members enriched in Hy. asiaticum and Ha. longicornis under different exogenous substance stresses were different, and the expression patterns of these genes were inconsistent. Molecular docking results showed that Ha. longicornis p450 members (HaloCYP3A4 and HaloCYP4B1), which were significantly up-regulated under CCEO stress, as well as Hy. asiaticum HyasCYP24A1 and HyasCYP4V2 (the HaloCYP3A4 and HaloCYP4B1 homologous genes), encode proteins that differ in their ability to metabolize CCEO components, but they all bind well to Germacrene D and naphthalene. Our study enriches the knowledge of the involvement of p450 family members of different tick species in the metabolism of essential oil components of plants, and provides a theoretical basis for further in-depth studies on the function of tick p450 enzymes.

Nontoxigenic Bacteroides fragilis (NTBF) is defined by the absence of the bft gene and corresponding B. fragilis toxin production; however, nontoxigenic status alone does not establish uniform safety or probiotic function. This review critically evaluates strain-level biological characteristics, safety, mechanisms, metabolites, and disease-model evidence. Selected strains and defined strain-derived preparations, including ZY-312, HCK-B3, NCTC 9343-derived polysaccharide A, and ZY-312-derived zwitterionic capsular polysaccharide preparation TP2, have shown immunomodulatory, barrier-associated, and microbial-community-modulating activities, predominantly in vitro and in animal models. Direct causal evidence is limited to specific strain–preparation–host–model combinations, whereas many changes in cytokines, tight-junction-associated proteins, microbial composition, and organic-acid profiles remain functional or associative. Protective effects have been reported in preclinical models of inflammatory bowel disease, necrotizing enterocolitis, antibiotic-associated diarrhea, Clostridioides difficile infection, and enterotoxigenic B. fragilis (ETBF)-associated tumorigenesis. However, findings are highly dependent on the strain, preparation, dose, administration timing, host, and model. Safety remains incompletely resolved because the absence of B. fragilis toxin (BFT) does not exclude opportunistic or systemic infection, antimicrobial-resistance mobility, bacterial translocation, permeability changes, or adverse effects during long-term administration. Metabolic effects may also be beneficial or adverse depending on the strain, host dietary and genetic background, and experimental context. Human evidence is primarily observational, and robust intervention trials are lacking. Accordingly, NTBF should be regarded as a heterogeneous group of strain-specific live-biotherapeutic candidates requiring rigorous strain-specific manufacturing, potency, dose, antimicrobial-susceptibility, and safety evaluation.

Bovine coronavirus (BCoV) is a key pathogen causing calf diarrhea and bovine respiratory diseases, bringing sustained economic losses to the cattle industry. As an RNA virus, BCoV possesses high mutation and recombination capacities, leading to prominent genomic genetic diversity. The genome contains hypervariable and conserved regions, with the S (especially S1), HE and Open Reading Frame (ORF4) genes serving as major variation hotspots linked to viral antigenicity, tissue tropism shift and immune evasion. Host immune pressure drives strong positive selection on S protein antigenic variation. This review discusses existing research limitations and proposes future directions including genomic surveillance, reverse genetics verification and broad-spectrum vaccine development to support BCoV prevention and control.