Bottles (∼180 mL) were produced by three-dimensional (3D) printing using food-grade glycol-modified poly (ethylene terephthalate) (PETG) as an alternative packaging for olive oil. Internal surfaces were functionalized with polydimethylsiloxane (PDMS) coatings containing either freeze-dried powder or freeze-dried aqueous extract powder from cv. ‘Cobrançosa’ olive leaf (0.92 ± 0.10 and 0.80 ± 0.13 mg GAE/mLPDMS, respectively), aiming to reduce oil oxidation while promoting olive leaf valorization. Functionalized bottles were compared with non-functionalized 3D-printed and conventional glass bottles. Olive oil quality was evaluated before and after accelerated storage (30 days, 40 °C, dark) using free acidity, peroxide value (PV), UV extinction coefficients (K232, K268), total phenolics, antioxidant activity, oxidative stability (OS), and sensory analysis. All samples suffered oxidation and quality downgrade from extra virgin to lampante (K232 > 2.60). However, oils stored under accelerated conditions in functionalized bottles showed significantly (P-value < 0.05) lower PV and K268, higher OS, better phenolic retention and lower rancidity (3.0–3.1 vs. 4.3) than glass-stored oils. Overall, functionalized bottles provided the greatest protection against oil sensory degradation, followed by non-functionalized and conventional glass bottles. This suggests that PETG/PDMS material itself exhibits a protective effect, enhanced by functionalization, although this empirical interpretation requires mechanistic confirmation. Unsupervised and supervised multivariate analysis confirmed the active packaging protective effect, with oils in functionalized bottles clustering closer to unstored samples. Both coatings were effective, though freeze-dried olive leaf powder being less technically-demanding is more practical. Thus, functionalized 3D-printed bottles emerge as a sustainable and active solution to reduce olive oil oxidation and support by-product valorization.
The yellow mealworm, Tenebrio molitor (L.) (Coleoptera: Tenebrionidae), is a significant stored-product pest, a valuable insect for animal feed production and a study system for immunology and entomopathogens, including entomopathogenic nematodes (EPNs). However, the efficacy and biocontrol potential of Australian EPN isolates against this host remain unexplored. We evaluated the virulence, establishment rate and reproductive potential of 17 Australian EPN isolates of Heterorhabditis and Steinernema in T. molitor larvae under laboratory conditions. All isolates successfully infected, killed and reproduced within T. molitor larvae, although their performance varied markedly. Heterorhabditis indica Hi.LMBT, Hi.LMI2 and Hi.HRN2 emerged as the most virulent isolates. EPN establishment rate in the host differed strongly among isolates, ranging from 5.8 to 17.2%, with Steinernema feltiae Sf.ECCS and Heterorhabditis marelatus Hm.ENCB showing the greatest establishment rate in the host. Reproductive potential ranged from ∼56,000 to ∼140,000 IJs per larva, with S. feltiae Sf.Y13 and Heterorhabditis zealandica Hz.NAR4 showing the highest reproduction. Multivariate and correlation analyses indicated substantial within-species variation for EPN species represented by multiple isolates, and that virulence, establishment rate and reproductive potential in T. molitor were not correlated with each other among isolates. Our results highlight considerable potential of Australian EPN isolates for mealworm control, while showing that candidate selection should not rely on virulence alone. Instead, effective screening should integrate virulence, establishment rate and reproductive potential to identify promising isolates that warrant further evaluation under realistic stored-product conditions.
RNA interference (RNAi) has shown great potential for pest control. However, the practical application of RNAi technology for pest control still faces challenges, such as target gene selection, dsRNA degradation, and low RNAi efficiency. In this study, with Callosobruchus maculatus as a model organism, the gene encoding fatty acid synthase (FASN) was selected as a target for insect control. After full-length sequence of CmFASN gene amplified using RACE technique, the gene structure and expression patterns were analyzed, which showed high conserved sequence structure and the spatiotemporal expression characteristics. Then, the dsFASN-CS-FCN nanoparticles were synthesized using ionic gelation methods with chitosan, fucoidan and dsFASN. The dsFASN-CS-FCN NPs exhibited excellent dispersibility, enhanced in vitro stability, and high RNAi efficiency. Compared to naked dsFASN, the dsFASN-CS-FCN nanoparticles significantly enhanced dsRNA stability in the insect's midgut fluid. Consequently, the dsFASN-CS-FCN nanoparticles could be effectively distributed in midgut. Importantly, dsFASN-CS-FCN exhibited high insecticidal activity against C. maculatus, leading to significantly increased mortality (58.00 ± 4.00% at 24 h post-treatment), reduced fecundity (77.6% reduction compared to the control), enhanced gene suppression efficiency (75.8% FASN knockdown), and decreased TAG synthesis (6.28 ± 0.28 ng/mg).Therefore, FASN could serve as a potential novel target for pest control. Not only did the dsFASN-CS-FCN NPs exhibit high stability and significantly enhance insecticidal efficacy, but they also improved dsRNA delivery efficiency, thereby establishing FASN as a promising target gene for pest control. Accordingly, these results could offer new perspectives for the application of RNAi technology in this field.
The search for sustainable alternatives to chemical insecticides has renewed interest in microbial agents capable of suppressing insect pests. The yellow mealworm (Tenebrio molitor) is both a stored-product pest and an industrially reared insect for food and feed, yet its integrated role in microbial bioinsecticide research remains comparatively underexplored. This review evaluates T. molitor as a biological, experimental and production-aware resource for the isolation, characterisation and development of microbial bioinsecticide candidates based on viruses, bacteria and fungi. A bibliographic analysis identified 134 relevant articles, with a marked increase in publications during the last decade and a clear predominance of studies on entomopathogenic fungi. Viral research is recent and mainly linked to densoviruses, pathology and colony-health surveillance, although densovirus-based formulations indicate potential against mealworm as a stored-product pest. Bacterial studies have focused on toxin-mediated, septicemic and immune-related interactions, particularly involving Bacillus thuringiensis, other Bacillales and nematode-associated symbionts. Fungal studies represent the most developed area, with Beauveria and Metarhizium widely investigated for soil baiting, strain recovery, virulence screening, infection mechanisms and formulation-related performance. Overall, the evidence supports T. molitor as a tractable larval host with potential as a standardised platform for linking pathogen discovery, host-response assays and formulation-oriented microbial bioinsecticide research. Further progress will require standardised rearing and exposure protocols, microbiota-aware assays, clearer reporting of infection routes, target-pest validation and scalable formulation studies.
Vertical overburden stress in deep maize grain piles compresses the packing, alters pore connectivity, and consequently affects airflow and coupled heat and moisture transfer during hot-air drying. This study investigated these effects using drying experiments and a coupled CFD–DEM framework. Maize packings under vertical stresses of 0, 50, 150, and 250 kPa were reconstructed by DEM, while CFD resolved interstitial airflow and transient intra-kernel heat and moisture transport. Increasing stress reduced porosity, increased tortuosity, and enhanced airflow resistance. The CFD–DEM model accounted for kernel non-sphericity and wall confinement and predicted pressure drops with mean deviations below 15% relative to measurements. At an inlet velocity of 0.5 m/s, the peak interstitial velocity decreased from 4.35 to 3.56 m/s as stress increased from 0 to 250 kPa, accompanied by expanded low-velocity regions and weaker convective transfer. The time required to reach 328.15 K increased from 20.6 min at 0 kPa to 22.4, 24.8, and 29.3 min at 50, 150, and 250 kPa, respectively. Similarly, drying to 14% (d.b.) required 323, 356, 406, and 475 min. These results demonstrate that vertical compression increases flow resistance and progressively delays heat and moisture transfer in maize grain piles.
Stored-product beetles threaten rural walnut storage, where alternatives to phosphine remain limited. We present an exploratory laboratory framework based on the pesticidal odorscape concept to compare essential-oil (EO) matrices using mixture-architecture descriptors, endpoint-specific behavioural and toxicological responses, and semi-quantitative acetylcholinesterase screening. Six species from northwestern Argentina yielded nine EO matrices, including CT1/CT2 profiles for three taxa. Gas chromatography–mass spectrometry profiles were summarized using diversity, dominance, concentration, and oxygenation descriptors. Activity against Carpophilus truncatus and Oryzaephilus mercator was assessed through two-choice spatial repellency using minimum effective dose thresholds (MED25/MED50) and net area under the curve, 24-h fumigant toxicity using median lethal concentration (LC50), and in vitro acetylcholinesterase (AChE) screening. Exploratory ordination suggested phenylpropanoid–terpene and oxygenation gradients. Responses were beetle-specific: within the tested dataset, Cuminum cyminum EO had the largest net-repellency point estimate against O. mercator, whereas Salimenaea integrifolia EO had the largest estimate against C. truncatus. The Pimpinella anisum CT1 matrix yielded the lowest LC50 values against both beetles, whereas its CT2 matrix attracted O. mercator. Because these endpoints involved distinct matrices, this contrast does not demonstrate behavioural–lethal decoupling within a single EO. AChE responses did not consistently parallel fumigant potency, and the concentration series precluded half-maximal inhibitory concentration estimation; AChE was therefore treated as a semi-quantitative endpoint. This study provides a hypothesis-generating basis for comparative EO-matrix profiling and future headspace-based IPM research. Independent-batch validation is needed to generalize endpoint-specific rankings, and same-matrix validation is required before multifunctional postharvest performance can be established.
Peach fruit is highly susceptible to oxidative damage and pathogen infection during postharvest storage, leading to rapid quality deterioration. Previous studies conducted by our team have suggested that propolis extract microcapsules (PM) can reduce fruit decay due to their superior antioxidant and antifungal capacity. This study investigated the physiological and transcriptional responses associated with PM treatment, with a particular focus on oxidative homeostasis. PM treatment significantly reduced decay rate from 83 % to 43 % at the end of storage and maintained key quality attributes, including firmness, titratable acidity, and ascorbic acid content, while suppressing respiration and ethylene production. Physiological analysis showed that PM treatment alleviated oxidative stress by reducing H2O2 and MDA accumulation and enhancing antioxidant enzyme activities. Transcriptomic analysis further revealed that PM modulated genes associated with reactive oxygen species (ROS) signaling, lipid metabolism, and stress responses, including RBOH and LOX. These results suggest that PM coordinates ROS production and scavenging processes, associated with a dynamic balance of oxidative homeostasis rather than the simple suppression of oxidative damage. In addition, pathways related to phenylpropanoid metabolism and defense responses were influenced, indicating an integrated stress adaptation mechanism. Overall, this study suggests that PM maintains postharvest quality by regulating oxidative homeostasis through coordinated physiological and transcriptional responses, providing insight into the role of exogenous treatments in postharvest preservation.
Essential oils (EOs), secondary metabolites derived from aromatic plants, are considered a sustainable alternative to synthetic agents in seed preservation. This review critically and comprehensively analyses the mechanisms, applications and future potential of EOs in seed storage. It summarises the existing knowledge on the antifungal, insecticidal and allelopathic properties of EOs and systematically addresses the concentration-dependent duality that may stimulate or inhibit seed germination and vigour. Advances in nanoencapsulation and combination treatments are examined for their capacity to enhance EO stability, enable controlled release, and improve efficacy. The analysis reveals that while EOs show promise for reducing dependency on synthetic pesticides and mitigating postharvest losses, their application is constrained by the absence of standardised procedures and limited knowledge of long-term ecological effects. To bridge these translational gaps, we propose a future research agenda focusing on improvement of application procedures, explanation of physiological implications, and creation of integrated seed management systems. In summary, the move of EO-based seed preservation from a promising concept to a viable agricultural tool requires shifting from descriptive investigations toward systems-level assessments of efficacy, safety, and sustainability.
Callosobruchus chinensis is a globally distributed pest that causes severe economic losses in stored edible legumes. Despite the economic impact of C. chinensis, the molecular mechanisms underlying its host recognition remain elusive. Odorant-binding proteins (OBPs), critical mediators of olfactory-driven behaviors including host location and reproduction, represent promising targets for pest management. In this study, qRT-PCR revealed that OBP6, OBP7, and OBP11 were highly expressed in the antennae of both male and female adults. Using fluorescence competitive binding assays, molecular docking, and site-directed mutagenesis, we characterized the binding affinities of these three OBPs to 23 mung bean volatiles. Notably, cis-3-hexenol, 2-hexenal, and (±)-limonene were identified as novel stable binders. Mutagenesis of five key residues (I81, Y104, D111, Y112, F113) abolished ligand binding, confirming their functional importance. Electrophysiological and behavioral assays demonstrated that these three compounds elicited antennal responses and exhibited attractive effects on both sexes. These findings provide promising candidates for the development of C. chinensis attractants and novel pest management strategies.
The red flour beetle, Tribolium castaneum, is a major secondary pest of stored grains and processed food products worldwide. This study evaluated the multifaceted insecticidal, repellent, and multi-generational suppressive efficacy of Lavandula dentata essential oil (EO) against T. castaneum adults, complemented by a molecular docking simulation to elucidate the potential mode of action. Chemical analysis revealed that the EO was dominated by oxygenated terpenoids (86.41%), primarily menthene glycol (46.09%) and trans-Dihydrocarvone (18.69%). In biological bioassays, the oil exhibited a dose-dependent contact toxicity in the residual film assay (LC50 = 0.165 mg/cm2), eliciting 84.0% mortality at 0.786 mg/cm2, while showing lower efficacy as a fumigant. Furthermore, the EO demonstrated potent repellent activity; at 1.57 mg/cm2, it induced an initial repellency of 96.0%, statistically equivalent to DEET (positive control of repellency), and maintained a significant residual superiority at lower thresholds over 24 h. Long-term assessment (30–45 days) showed absolute F1 progeny suppression (100%) at the LC90 baseline (12.44 mg/g), performing equally to chlorpyrifos (positive control of toxicity). To corroborate these findings, molecular docking was executed against critical insect targets: Acetylcholinesterase (AChE) and Odorant Binding Protein 12 (TcOBP C12). Menthene glycol and trans-Dihydrocarvone exhibited moderate binding energies within the active sites, with menthene glycol securing the highest affinity scores up to −6.56 kcal/mol for AChE and −6.91 kcal/mol for TcOBP C12. These computational insights are consistent with the observed neurotoxic mortality and behavioral avoidance dynamics. Overall, these findings highlight L. dentata EO as a promising bio-rational alternative for the sustainable management of stored-grain pests.
The rice weevil (Sitophilus oryzae) causes substantial post-harvest grain losses globally. With growing concerns over resistance and the safety of conventional fumigants, ethyl formate (EF) has emerged as a promising alternative due to its rapid action and minimal residue formation. This study systematically evaluated the efficacy of the EF fumigant against S. oryzae using 1-L laboratory bioassay chambers and a 9-L miniature silo system under varying environmental and operational conditions. In 1-L chambers, EF demonstrates concentration-dependent toxicity with lethal concentration (LC50) values of 18.8, 15.97, and 13.27 μL/L at 30, 25, and 20 °C, respectively, following 4 h exposure. At 20–40 μL/L and 30 °C, EF reduced larval and pupal emergence by 5- and 14.8-fold, respectively, compared with the control, while achieving 75–100% adult mortality. By extending exposure from 4 to 24 h, the efficacy was substantially enhanced, increasing adult mortality from 8% to 70% at 15 μL/L. However, grain loading significantly reduced performance, with mortality declining from 97% (0% loading) to 52% (90% loading), indicating EF's penetration limitations. Whereas, in the 9-L miniature silo, static fumigation (160 μL/L, 24 h, 30 °C) produced highly position-dependent mortality: 100% (top), 35.5% (middle), and 20.3% (bottom). Importantly, forced air circulation resulted in 100% mortality across all positions, demonstrating that active airflow is essential for uniform fumigant distribution in grain-filled systems. The addition of CO2 enhanced the efficacy of EF, reducing the required EF concentration for complete mortality by 41.11% (from 80 to 65 μL/L), and LC50 dropped from 65.92 μL/L in the control to 49.59 μL/L at 30% CO2, representing a consistent of 1.32-fold reduction in LC50 level. These findings establish EF as an effective fumigant against S. oryzae and highlight that exposure duration, grain loading, CO2 supplementation, and air circulation critically determine its practical efficacy for sustainable stored-grain protection.
Vertical CO2 concentration stratification commonly occurs during controlled-atmosphere treatment in large concrete silos. Although recirculation improves gas distribution, concentrations at key monitoring points may continue to decline briefly after startup, creating a risk of delayed intervention based only on current measurements. To enable automated and intelligent recirculation control, two full-scale experiments were conducted in a 10,000 t concrete maize silo. Data from the first experiment were used to develop a conditional multi-step forecasting model, which was then deployed for closed-loop validation in the second experiment. The modeling experiment yielded 4723 time-series records. Representative episodes showed a non-monotonic response at the inspection-door monitoring point, with CO2 concentration initially decreasing and then recovering; the declining phase lasted 0.42-0.58 h. A multilayer perceptron (MLP), Transformer, and long short-term memory (LSTM) network were compared within a sequence-to-sequence (Seq2Seq) framework. The LSTM performed best at the control point, achieving a test-set mean absolute error of 0.148 percentage points, root mean square error of 0.209 percentage points, and R2 of 0.9355. During validation, the system twice predicted that the future minimum concentration would fall below the 35% threshold and automatically activated recirculation. Predicted minima were 34.98% and 34.97%, while measured minima remained at 35.95% and 35.75%, respectively. Recirculation also improved vertical uniformity, with the daily coefficient of variation decreasing from 0.312 to 0.012 and from 0.173 to 0.042. The proposed system identified threshold risks before the measured concentration fell below the control threshold and actively regulated in-silo gas distribution, providing a practical approach for precise CO2-controlled atmosphere management in large concrete silos.
Seeds of the genus Canavalia contain several bioactive proteins with known toxic effects, including the lectin concanavalin A, ureases, canatoxin, and vicilins. In this study, the toxicity of Canavalia gladiata (Jacq.) DC. and Canavalia rosea (Sw.) DC. seeds against the cowpea weevil, Callosobruchus maculatus (F.), was evaluated through morphological, biological, proteomic, and in silico analyses. Compared with the host species, Vigna unguiculata (L.), both Canavalia species produced larger, harder seeds with thicker seed coats and darker coloration. Oviposition by C. maculatus was reduced by 69.45% on C. rosea and 74.19% on C. gladiata, while larval penetration was completely inhibited. Larvae remained trapped within the eggs, exhibited apparent atrophy, and died without entering the seeds. Cotyledon flours from both species were toxic to larvae, reducing survival when at concentrations of 2% for C. rosea and at 10% for C. gladiata. Larval biomass was significantly reduced in artificial seeds containing 1% C. rosea flour and 2% C. gladiata flour. Furthermore, the flours of C. rosea and C. gladiata were lethal to insects at concentrations of 10% and 20%, respectively. Proteomic analysis identified 304 proteins annotated based on matches to Glycine max database entries, including defense-related proteins assigned to conserved urease and cupin protein families, such as putative β-conglycinins and basic 7S globulins. Molecular docking analyses suggested that putative urease homologs may interact with cathepsin L from C. maculatus, whereas putative β-conglycinin and basic 7S globulin homologs exhibited affinity for N-acetylglucosamine tetramers, indicating potential interactions with chitin-containing structures such as the insect peritrophic matrix. Collectively, these results indicate that C. rosea and C. gladiata possess both physical and biochemical defenses that confer resistance to C. maculatus. The identified seed proteins represent promising candidates for further investigation as bioinsecticidal agents in stored-product pest management.
This study assessed ginger-derived iron oxide nanoparticles (FeO-NPs) and five plant growth-promoting rhizobacteria (PGPR) strains against adult Tribolium castaneum. The material was characterised by UV–visible spectroscopy, X-ray diffraction, ATR–FTIR, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Mortality was evaluated using diet-incorporation bioassays, whereas repellency was assessed using a half-filter-paper area-preference assay; each treatment comprised three independent Petri plates containing ten adults. FeO-NPs and Pseudomonas sp. HY13KR were tested individually and in combination, and protein-normalised acetylcholinesterase (AChE) and catalase (CAT) activities were quantified. Mortality increased with FeO-NP dose and exposure time: 25 mg g−1 diet caused 83.3 ± 5.8% mortality by Day 3 and 100% by Day 4, whereas 12.5 mg g−1 required nine days to reach 100%. HY8N and HY13KR caused 100% mortality by Day 3. The combined treatment reached 100% mortality by Day 2 and produced a greater time-integrated mortality response than HY13KR alone (Tukey-adjusted p = 0.0187). Maximum repellency was 93.3 ± 11.5% at 0.15 mg mL−1 after 7 h and declined thereafter. The combined treatment produced the lowest AChE (0.0796 ± 0.0094 μmol min−1 mg−1 protein) and CAT (3.3946 ± 0.0755 μmol H2O2 min−1 mg−1 protein) activities; treatment effects on both enzymes were significant (p < 0.0001). Characterisation showed an agglomerated Fe- and O-containing material. Overall, the FeO-NP and PGPR treatments elicited substantial mortality, repellency, and biochemical responses under laboratory conditions.
Rapeseed's high moisture and oil content make it vulnerable to spoilage. This study investigated ultrasound (US) pretreatment combined with hybrid infrared (IR)-hot air drying on rapeseed quality and energy performance. A Taguchi L16 array optimized four parameters: IR distance (7, 10.5, 14 and 17.5 cm), air temperature (50, 60, 70 and 80 °C), IR power (0, 200, 300 and 400 W), and US time (0, 4, 8 and 12 min). Distance significantly affected oil content, while temperature was the sole significant factor for protein content. IR power and US time strongly reduced drying time and increased drying rate and specific moisture extraction rate (SMER). The optimal compromise was 14 cm, 50 °C, 300 W, and 12 min US. This condition (Run 9) yielded oil content 41.32%, protein 24.20%, drying rate 0.419 g water/min, SMER 22.09 g water/kWh, and drying time 30 min, with desirability D = 0.877. The novelty of this study lies in combining ultrasound-assisted hybrid infrared–hot air drying and multi-objective optimization to evaluate product quality and energy efficiency in rapeseed drying simultaneously.
