TdGASA2, a cysteine-rich Snakin/GASA protein from Triticum turgidum, enhances stress-mediated inactivation of Listeria monocytogenes and improves the preservation performance of chitosan-based biodegradable active packaging films.

Chitosan-Based Composite Film Containing Cell-Free Supernatant of Lactiplantibacillus plantarum JC2211 for Chilled Pork Preservation

Traditional fermented vegetables are important resources for screening excellent antibacterial lactic acid bacteria (LAB). In this study, a strain of Lactiplantibacillus plantarum JC2211 with broad-spectrum antibacterial activity against Salmonella Typhimurium (S.T), Staphylococcus aureus (S.a), Listeria monocytogenes (L.m), and Pseudomonas aeruginosa (P.a) was isolated from Yangzhou pickles. The minimum inhibitory concentration (MIC) of its cell-free supernatant (CFS) against all four pathogens was 25 μL/mL. The strain exhibited favorable biosafety and strong environmental adaptability, tolerating 8% NaCl, pH 3.0–10.0, and 0.3% bile salt. The CFS exerted synergistic antibacterial effects via multiple pathways, including increasing cell membrane permeability, reducing membrane potential, decreasing intracellular ATP levels, and inducing ROS accumulation. Metabolite identification indicated that organic acids (dominated by D-lactic acid at 9.37%, citric acid at 8.00%, and phenyllactic acid at 4.42%) were the main components. Using chitosan (CS) as the base material, composite preservation films were fabricated by incorporating 10–50% CFS. The composite film containing 40% CFS (CS/CFS40) exhibited the optimal comprehensive performance, with ABTS and DPPH radical scavenging rates of 90.24% and 79.17%, respectively, along with satisfactory tensile strength (18.70 MPa) and elongation at break (22.93%). In chilled pork preservation, the CS/CFS40 film significantly inhibited the proliferation of spoilage microorganisms, and effectively retarded lipid oxidation. Moreover, the film suppressed the colonization of L.m and S.T on meat surfaces, with bacterial loads maintained at 2.07–2.67 lg CFU/g and 2.92–2.99 lg CFU/g, respectively, over 7 days of refrigeration. Collectively, the CS/CFS40 composite film extended the shelf life of chilled pork to approximately 6 days. This study provides a novel natural biological preservative and eco-friendly active packaging material for chilled meat preservation.

Staphylococcus cohnii mediated production of perillic acid from limonene and synthesis of its amide derivatives for the induction of apoptosis in TNBC Cells

Eri Silk Fibroin-Mediated Biosynthesis of Silver Nanoparticles with In Vitro Antibacterial Activity Against Vibrio parahaemolyticus

The emergence of antibiotic-resistant Vibrio parahaemolyticus poses a challenge to sustainable shrimp aquaculture and highlights the need for effective antibacterial alternatives. In this study, silver nanoparticles were biosynthesized using Eri silk fibroin (ESF) as both a reducing and stabilizing biopolymer. Eri silkworms can be reared on cassava leaves, an abundant agricultural by-product in Thailand, thereby supporting waste valorization and the circular bioeconomy. Optimal synthesis was achieved at an AgNO3-to-ESF weight ratio of 1:4, 60 °C, and 4 h, yielding 82.8% ESF-AgNPs with a particle size of 10.8 ± 2.3 nm and a polydispersity index of 0.19 ± 0.01. TEM, XRD, and XPS confirmed the formation of well-dispersed metallic Ag0. The particles remained colloidally stable for at least four weeks. ESF-AgNPs exhibited minimum inhibitory and bactericidal concentrations of 12.5 and 25 µg/mL, respectively; inhibited biofilm formation by 52.45–99.98%; and increased intracellular reactive oxygen species generation. After 72 h, silver release reached 5.70% in deionized water and 9.30% in TSB containing 3% NaCl. Artemia franciscana survival remained 96.2% after 24 h at the MBC. These findings support ESF as a sustainable platform for producing antibacterial and antibiofilm AgNPs with a preliminary safety margin, although further in vivo efficacy and chronic-toxicity studies are required before practical application.

Biosynthesized chitosan nanoparticles from Krameria lappacea: a strategy to ameliorate coccidiosis-induced intestinal dysfunction

Coccidiosis is a major parasitic disease caused by Eimeria species that induces intestinal damage, oxidative stress, and impaired nutrient absorption. The risk associated with drug-resistant strains and other adverse effects related to conventional anticoccidial drugs necessitates the development of safer natural alternatives. Thus, in this study, we examined the anticoccidial efficacy of biosynthesized chitosan nanoparticles (CNPs) derived from Krameria lappacea root extract against Eimeria papillata -induced murine coccidiosis. Chitosan nanoparticles were biosynthesized using K. lappacea root extract and characterized by transmission electron microscopy (TEM), UV–visible spectroscopy, and Fourier-transform infrared spectroscopy (FT-IR). Male C57BL/6 mice were experimentally infected with 10³ sporulated oocysts of E. papillata and treated orally with CNPs at doses of 5, 10, and 20 mg/kg, while amprolium (120 mg/kg) was used as a reference coccidian drug. Fecal oocyst output, body weight changes, jejunal histopathology, intracellular parasitic stages, oxidative stress biomarkers, antioxidant enzyme activities, glucose, and total protein contents were evaluated on day five post-infection. TEM analysis revealed that the synthesized CNPs were predominantly spherical with particle sizes ranging from 57.01 to 83.05 nm with an average diameter of about 70.16 nm. FT-IR analysis indicated the presence of functional groups associated with alcohols, amines, sulfates, and halo compounds. Infection with E. papillata caused significant body weight loss, increased oocyst shedding, severe jejunal histopathological alterations, elevated nitric oxide (NO) and hydrogen peroxide (H 2 O 2 ) levels, and reduced the levels of glucose, total protein, catalase (CAT), and glutathione peroxidase (GPx). Treatment with CNPs significantly reduced fecal oocyst shedding in all treated groups; however, the 5 mg/kg dose was the most effective, lowering oocyst output to 1.308 × 10 6 ± 2.54 × 10 5 oocysts/g feces compared with 7.196 × 10 6 ± 2.77 × 10 5 oocysts/g feces in infected untreated mice. The reductions achieved with the 10 and 20 mg/kg CNP doses were less pronounced. CNPs administration also markedly decreased intracellular parasitic stages, improved jejunal histological architecture, restored glucose and protein contents, promoted antioxidant capacity, and lowered oxidative stress. The therapeutic efficacy of CNPs was comparable to or superior to that of the reference drug, amprolium. CNPs exhibited potent anticoccidial, antioxidant, and protective effects against E. papillata infection in mice. These findings suggest that CNPs are a promising natural alternative for the management of coccidiosis, warranting further investigation into their mechanisms of action, safety, and potential applications in veterinary medicine.

Biosynthesis and functionalization of recombinant bovine lactoferrin: Alginate-mediated stabilization and MTGase-induced gelation for anthocyanin delivery.

Bovine lactoferrin (BLF) is a milk-derived glycoprotein with diverse biological activities, including antimicrobial, antioxidant, and immunomodulatory functions, with potential for applications in functional foods and nutraceuticals. However, its practical utilization remains limited by key challenges: low efficiency of traditional extraction methods, poor gastrointestinal stability, and a narrow range of application forms. To address these issues, this study developed an integrated strategy spanning from efficient production to functional application. First, the Pichia pastoris expression system was optimized through signal peptide engineering and chaperone co-expression, achieving high-yield secretory production of recombinant BLF (rBLF) at 232.6 mg/L in shake-flask fermentation. Subsequently, rBLF was complexed with sodium alginate (NaAlg) via electrostatic self-assembly to form nanocomposites for gastrointestinal protection. The rBLF-NaAlg complex exhibited remarkable resistance to simulated gastric digestion, with only a 23.7% reduction in particle size, significantly lower than the 71.1% reduction observed for free rBLF. Furthermore, a three-dimensional hydrogel delivery system was constructed through microbial transglutaminase (MTGase)-catalyzed cross-linking. This system demonstrated encapsulation and sustained release of anthocyanins as a model bioactive compound. The gel structure and performance showed a clear enzyme concentration dependence: moderate cross-linking (<80 U/g) resulted in a uniform and dense network, enhancing encapsulation efficiency and providing controlled release. This work establishes a complete technological pathway from high-yield production and stabilization to functional expansion, demonstrating that rBLF can be transformed from a labile bioactive protein into a dual-functional material with both nutritional and delivery capabilities. This integrated strategy provides a viable solution for developing advanced BLF-based functional foods and nutraceutical delivery systems.

Harnessing the endophytic Clavispora lusitaniae for the biogenic synthesis of ethylene glycol-capped cerium oxide nanoparticles: a green approach to combat respiratory Pseudomonas aeruginosa

The utilization of endophytes as specialized microbial cell factories offers a sustainable and high-efficiency platform for the biosynthesis of functionalized nanomaterials. This study investigates the potential of a novel endophytic yeast, Clavispora lusitaniae, to produce cerium oxide nanoparticles (CeO₂NPs) and evaluates their efficacy against extensively drug-resistant (XDR) P. aeruginosa. An endophytic yeast, C. lusitaniae, was isolated for the first time from the medicinal plant Artemisia judaica and employed for the biosynthesis of CeO₂NPs, followed by surface capping with ethylene glycol (EG) to modify the nanoparticle surface properties. The synthesized nanoparticles were characterized using UV-Vis, FTIR, XRD, TEM, and DLS. These analyses confirmed the formation of spherical EG-CeO₂NPs with an average size of 8–20 nm. EG-CeO₂NPs exhibited strong antibacterial activity against XDR P. aeruginosa strains, with a minimum inhibitory concentration ranging from 0.6 to 1.25 mg/mL. Furthermore, these nanoparticles demonstrated potent anti-biofilm efficacy, achieving reductions of up to 89%. Mechanistic investigations demonstrated that EG-CeO₂NPs disrupt bacterial cell membranes, leading to intracellular protein leakage and elevated lipid peroxidation (indicated by increased malondialdehyde levels). Furthermore, the expression levels of quorum sensing (e.g., lasR and rhlR) and virulence-associated genes (e.g., toxA and exoS) were markedly downregulated by up to 87% compared to untreated controls. This study establishes C. lusitaniae as a robust microbial cell factory for synthesizing functionalized CeO₂NPs with potent activity against XDR P. aeruginosa. Our results demonstrate the potential of microbial bioprocessing in engineering prospective nanotechnological platforms to combat antimicrobial resistance. However, further studies evaluating colloidal behavior under physiologically relevant conditions, mammalian-cell cytotoxicity, and in vivo efficacy are required before biomedical translation.