Fei Wang

Microbial contamination remains a major challenge in food systems, creating demand for stable natural antimicrobials. This study investigates the inducible antibacterial response of Hermetia illucens and characterized the black soldier fly defensin-like peptide DLP4. Larvae were challenged with Staphylococcus aureus or Escherichia coli, and hemolymph activity, antimicrobial-peptide gene expression, C18 solid-phase extraction fractions, and LC–MS/MS profiles were evaluated. Synthetic mature DLP4 was further assessed for antibacterial spectrum, physicochemical stability, and structural properties. Hemolymph antibacterial activity varied with treatment and time, while DLP4 and CLP1 showed distinct transcriptional responses. Antibacterial activity was concentrated in early fractions, with F3 showing the greatest activity. LC–MS/MS detected a conserved DLP-family motif and a cysteine-rich defensin-like peptide in F3, whereas the complete 40-amino-acid sequence of synthetic DLP4 was confirmed. DLP4 showed strong, strain-dependent activity against Gram-positive bacteria, including Bacillus subtilis, Listeria ivanovii, and Staphylococcus spp., while no MIC endpoint was detected for the tested E. coli strains. DLP4 retained substantial activity after heat, ultraviolet, storage, pH, NaCl, and most metal-ion treatments, although Fe³⁺ reduced activity. These findings support DLP4 as a stable, Gram-positive-active antimicrobial candidate for further evaluation in food systems.

Antimicrobial resistance (AMR) was associated with 4.95 million deaths in 2019 and may cause 10 million deaths annually by 2050. We synthesize evidence on how the black soldier fly (Hermetia illucens) has evolved an expanded antimicrobial peptide (AMP) repertoire, which structural features drive family-specific activity, what mechanisms are directly demonstrated in H. illucens, and how AI contributes. PubMed, Web of Science, and Scopus (plus targeted Google Scholar) were searched from inception to 1 February 2026; studies were included when they reported BSF peptide identities, expression/proteomics, evolutionary analyses, quantitative activity, mechanistic assays, or BSF-focused computation, and claims were tiered as predicted, expression-supported, or experimentally supported. The literature supports 50–80 BSF AMP genes, plausibly shaped by gene duplication and balancing/diversifying selection in microbe-rich substrates, with marked induction plasticity across tissues, development, diet, and challenge. SAR is family-dependent: defensin-like peptides rely on disulfide-stabilized CSαβ folds and cationic surface topology; cecropin-like peptides on amphipathic α-helices with selectivity trade-offs; attacin-like peptides on β-architecture where charge-based heuristics are weak; and diptericin/proline-rich peptides remain largely inference-driven in BSF. Mechanistic evidence is strongest for membrane/envelope-centered killing by DLP4 and pore-associated envelope disruption by a recombinant attacin-like peptide, whereas pore geometry, oligomerization, intracellular targets, and broad “resistance-proof” claims remain unresolved. Key gaps include assay heterogeneity, salt/serum stability, selectivity/toxicity, resistance-risk testing, and limited in vivo validation, which must be addressed for credible AMR-relevant translation.

The global escalation of organic waste generation, coupled with rising protein demand and environmental pressure, necessitates innovative, circular approaches to resource management. Hermetia illucens (Black Soldier Fly, BSF) has emerged as a leading candidate for integrated waste-to-resource systems. This review examines BSF biological and genomic adaptations underpinning waste conversion efficiency, comparative performance of BSF bioconversion versus traditional treatments, nutritional and functional attributes, techno-economic, regulatory, and safety barriers to industrial scale-up. Peer-reviewed studies were screened for methodological rigor, and data on life cycle traits, conversion metrics, and product compositions were synthesized. BSF larvae achieve high waste reductions, feed-conversion efficiencies and redirect substrate carbon into biomass, yielding net CO₂ emissions as low as 12–17 kg CO₂ eq ton⁻¹, an order of magnitude below composting or vermicomposting. Larval biomass offers protein, lipids (notably lauric acid), micronutrients, chitin, and antimicrobial peptides, with frass serving as a nutrient-rich fertilizer. Pathogen and antibiotic resistance gene loads decrease during bioconversion. Key constraints include substrate heterogeneity, heavy metal accumulation, fragmented regulatory landscapes, and high energy and capital demands. BSF systems demonstrate superior environmental and nutritional performance compared to conventional waste treatments. Harmonized safety standards, feedstock pretreatment, automation, and green extraction methods are critical to overcoming scale-up barriers. Interdisciplinary innovation and policy alignment will enable BSF platforms to realize their full potential within circular bio-economies.

Safe antibiotic substitutes are needed given the rise in antimicrobial resistance, environmental contamination, and stringent antibiotic regulations. Insect-derived antimicrobial peptides (AMPs) are promising candidates due to their antimicrobial activity, stability, and safety. This study investigates the antimicrobial mechanism of crude AMP extracts and their physicochemical characteristics in black soldier fly larvae (BSFL). The results indicated that BSFL reared on a wheat bran diet exhibited significantly improved growth performance and AMP production when compared to the other three diets. AMP extracts showed enhanced antimicrobial activity and physicochemical stability, including temperatures and metal ions except Cu⁺. Moreover, AMP extracts disrupted the cell membrane and inhibited the cell cycle of Staphylococcus aureus (S. aureus), thus exhibiting antimicrobial activity. Furthermore, transcriptomic and KEGG enrichment analyses identified 509 differentially expressed genes (DEGs) related to the Toll and IMD signaling pathways. STRING and GeneMANIA analyses confirmed the association of these pathways with immune response and AMP secretion. qRT-PCR results showed elevated expression of immune genes (GNBP3, NFKBIA, GADD45, and Spz) in BSFL following S. aureus immunization, consistent with RNA-seq findings. These findings offer a valuable reference for using AMPs as antibiotic substitutes in animal feeds and highlight the need for further research on AMP purification and the synergistic regulation of protein synthesis and AMP production in BSFL.

With the increasing demand for nutrition and health, many researchers are trying to develop a rice product with lower aging rate and convenient nutrient fortification. Being composed of high amylopectin content, cassava starch (CS) shows a lower retrogradation tendency compared to rice starch. So, it has a broad application prospect to partially replace rice starch with CS in rice by extrusion technology. In this study, a new extruded rice (ER) was prepared by broken rice flour and CS using single-screw extruder through “improved extrusion cooking technology,” and the maximum addition level of CS in ER was 30%. Color parameters and texture profile analysis showed that ER was a little darker in appearance with lower hardness, adhesiveness and chewiness. Rapid visco analysis demonstrated that the viscosity of ER paste appeared earlier during the initial heating phase and displayed a lower retrogradation trend than normal rice in the cooling process. The gelatinization temperature and gelatinization enthalpy decreased with the increasing CS in ER, while the degree of gelatinization increased to 76.36% when the content of CS was 30% after extrusion. The X-ray diffraction patterns of control was typical A-type structure, while ER changed to V-type structure with a lower degree of crystallinity. The microstructure observation showed that ER exhibited a looser and more porous structure with increasing the content of CS, which facilitated easier cooking and nutritional enhancement.