The gut microbiome significantly influences the health and productivity of silkworms (Bombyx mori), the cornerstone of sericulture. With the increasing use of cost-effective artificial diets in sericulture, it is crucial to understand how these diets impact the silkworm gut microbiomes. Here we employed 16S rRNA sequencing to delineate the impact of three distinct dietary regimens on the silkworm gut microbiomes: exclusive mulberry leaf diet (SY), exclusive artificial feed diet (SL), and a sequential transition from artificial feed to mulberry leaves (ZS). Our results unveiled stark differences in microbial diversity across the groups, with the ZS group displaying an intermediary complexity. LefSe and random forest analyses identified Methylobacteriaceae, Microbacterium, and Rhodococcus as significantly enriched in the ZS group, suggesting their potential to facilitate silkworms’ adaptation to dietary transitions. Functional profiling revealed differential pathway regulation, indicating a metabolic reconfiguration in response to dietary modulations. Notably, the enrichment of Lactobacillus and Weissella in both the SL and ZS groups highlights their potential as probiotics in artificial diets. Our findings provide insights into the diet adaptation mechanisms of silkworm gut microbiota, paving the way for harnessing the intestinal bacteria to enhance silkworm health and silk production through targeted microbial interventions in sericulture practices.

The genus Macromotettixoides Zheng, Wei & Jiang, 2005 is reviewed. Four new species of the genus, M. daiyunshanensis Deng, sp. nov., M. curvicarina Deng, sp. nov., M. convexa Deng, sp. nov. and M. shengtangshanensis Deng, sp. nov. are described with detailed illustrations of external morphology. Two new synonyms are established: M. jinggangshanensis, syn. nov. is synonymized with M. jiuwanshanensis Zheng, Wei & Jiang, 2005; M. parvula Zha & Wen, 2017, syn. nov. is synonymized with M. undulatifemura Deng, Zheng & Yang, 2012. Additionally, an updated key to species of the genus is given.

Addressing aquatic phosphate pollution requires advanced materials that combine high selectivity with recyclability. Here, we present a hierarchically structured composite integrating Mg-Fe layered double hydroxides (LDHs) with magnetic biochar derived from mulberry branches—an abundant agricultural byproduct. Through hydrothermal synthesis, the composite achieves a unique architecture combining Fe₃O₄-enabled magnetic recovery (2.63 emu·g⁻¹ saturation) with LDHs’ anion exchange capacity and biochar’s porous network. Systematic characterization reveals phosphate capture mechanisms dominated by hydrogen bonding through deprotonated carboxyl groups, inner-sphere complexation with metal oxides, and interlayer anion exchange, enabling 99.22% phosphate removal at optimal conditions (pH 6, 25 °C). Crucially, the material demonstrates exceptional selectivity over competing Cl⁻ and NO₃⁻ ions while maintaining 87.83% efficiency after three regeneration cycles via alkaline treatment. Kinetic and thermodynamic analyses confirm chemisorption-driven uptake aligned with pseudo-second-order kinetics (R² > 0.9998) and Langmuir monolayer adsorption (7.72 mg·g⁻¹ capacity). This waste-derived magnetic composite establishes a sustainable paradigm for eutrophication control, merging selective phosphate sequestration with energy-efficient recovery for circular water treatment applications.

The transition from traditional mulberry leaf feeding to artificial diet cultivation represents a major advancement in modern sericulture, yet the genetic mechanisms driving this adaptation remain largely unexplored. This study investigates the genomic basis of artificial diet adaptation in the silkworm strain Guican No.5 through whole-genome resequencing and transcriptome analysis. We identified 8,935,179 single-nucleotide polymorphisms (SNPs) across all chromosomes, accounting for 2.01% of the genome, with particularly high densities observed in chromosomes 23, 26, and 28. Our analysis also revealed 879 novel transcripts, many of which are involved in digestion, detoxification, and stress response pathways. Key novel genes, including three carboxylesterases, two cytochrome P450s, one heat shock protein, and one copper/zinc superoxide dismutase, exhibited varying degrees of sequence similarity to known proteins, suggesting modifications to existing genetic frameworks. Notably, one novel P450 gene displayed only 74.07% sequence identity with its closest homolog, indicating the emergence of a new protein sequence. Additionally, several key genes showed high similarity to wild silkworm (Bombyx mandarina) proteins, underscoring their evolutionary origins. These findings provide valuable insights into the molecular mechanisms underpinning artificial diet adaptation in silkworms and offer genomic resources to enhance artificial diet formulations and breeding programs in sericulture.

Chromium is a severe heavy metal pollutant with significant environmental risks. The effects of Chromium on the digestion of Bombyx mori (silkworms) are of particular importance due to their ecological and economic significance. Herein, RNA sequencing was conducted on nine midgut samples from silkworms exposed to control, 12 g/kg and 24 g/kg Chromium chemical diets. Comparative transcriptomics revealed that under moderate Chromium exposure, there was a significant increase in up-regulated genes (1268 up-regulated to 857 down-regulated), indicating a stimulation response. At higher stress levels, a weakened survival response was observed, with a decrease in up-regulated genes and an increase in down-regulated genes (374 up-regulated to 399 down-regulated). A notable shift in cellular responses under medium chromium exposure was exposed, signifying the activation of crucial metabolic and transport systems and an elevation in cellular stress and toxicity mechanisms. The observation of up-regulated gene expression within xenobiotic metabolism pathways suggests a heightened defense against Chromium-induced oxidative stress, which was primarily through the involvement of antioxidant enzymes. Conversely, high-dose Chromium exposure down-regulates the folate biosynthesis pathway, indicating biological toxicity. Two novel genes responsive to pressure were identified, which could facilitate future stress adaptation understanding. The findings provide insights into the molecular mechanisms underlying silkworms’ digestion response to Chromium exposure and could inform its biological toxicity.