Search Results (1,137)

Hastelloy X exhibits outstanding thermal fatigue resistance, making it a promising material for repairing 50CrVA landing gear via directed energy deposition (DED). However, the substantial differences in composition and thermophysical properties between 50CrVA and Hastelloy X pose challenges by affecting interfacial microstructure and surface quality. This study investigates the effect of DED process parameters (laser power p, powder feed rate f, scanning speed v, and overlap rate) on the dilution ratio (η), microscopic morphology, surface flatness (ζ), and porosity of Hastelloy X claddings on a 50CrVA substrate. An optimization methodology integrating thermal–flow coupled simulation models and orthogonal experiments is developed to fabricate high-quality claddings. Furthermore, the corrosion–wear performance of the claddings is evaluated. The results indicate that the η of a single track increases with higher p or lower f, while it first increases and then decreases with the increase in v. Ablation marks tend to occur at excessive p or insufficient f, while low v causes surface ripples. The ζ of a single layer initially improves and subsequently deteriorates with increasing overlap rate. Porosity is significantly influenced by p and f. The optimal p, f, v, and overlap rate are 1600 W, 2.4 g/min, 240 mm/min, and 55%, respectively. The wear resistance of the cladding is nearly identical to that of the substrate, while corrosion resistance is significantly improved. This work provides a theoretical foundation for high-performance repair of 50CrVA landing gear in aircraft. Full article

Keratinous wastes, generated from various industries such as poultry processing, slaughterhouses, and salons, accumulate in the environment due to their slow degradation caused by high disulfide cysteine bonds. Traditional methods of managing these wastes, including incineration, composting, open-air burning, and landfilling, have several disadvantages, such as environmental pollution, release of toxic compounds, and breeding of pathogenic and multidrug-resistant microorganisms. Microbial keratinases, produced by bacteria, fungi, and actinomycetes, offer an eco-friendly alternative for valorizing keratinous waste into valuable peptides and amino acids. The biodegradation of keratinous biomass involves four sequential steps: adhesion, colonization, production of keratinolytic enzymes, and breakdown of the keratin substrate. Optimization of culture conditions, such as pH, temperature, substrate concentration, and metal ions, can enhance keratinase production for industrial applications. Keratinases have multifaceted applications in various sectors, including cosmetics, organic fertilizers, leather treatment, animal feed, detergents, and pharmaceuticals. This review highlights the need to explore keratinolytic strains further and improve keratinase yields to develop sustainable solutions for keratinous waste management and generate value-added products, promoting a circular economy. The techno-economic considerations and current limitations in industrial-scale keratinase production are also discussed, emphasizing the importance of future research in this field. Full article

For small ectotherms, thermal conditions and habitat structure can drive local adaptations in behavior and habitat use. The water anole, Anolis aquaticus, is a semiaquatic lizard occurring along streams in lowland tropical sites, as well as at higher elevations with greater thermal variability. We studied their thermal ecology, habitat use, and behavior at a high- (~1100 m) and low-elevation (~sea level) site in Costa Rica to assess the relationship between thermal environment and behavioral ecology. We measured behavior through focal observations (rates of movement, head turns, and feeding) and recorded the range of environmental temperatures, body temperatures, air and substrate temperatures of perches, and habitat use (perch location relative to water’s edge and current, substrate, cover, and visibility). The low-elevation site had higher minimum temperatures and a smaller range of available temperatures. Body temperature and size varied with site and sex: low-elevation males had the highest body temperatures, and high-elevation males were largest. Individuals at the high-elevation site were less active, perched closer to the water’s edge (shorter horizontal perch distance), and more often used the ground or rocks near an eddy as a substrate than individuals at the low-elevation site. The temperature and habitat structure of water courses can manifest phenotypic differences in ecology and behavior. Full article

Black Soldier Fly Larvae Meal (BSFLM) has gained attention as a sustainable feed ingredient in aquaculture, yet its functional properties at the cellular level remain underexplored. This study evaluated the antioxidative and proliferative effects of BSFLM derived from larvae fed different waste-based substrates (Kitchen Waste (KW); Agricultural Waste (AW); Aquaculture Sludge (AS); Aquaculture Offal (AO); Mix (MX)), using the Atlantic salmon (Salmo salar) SHK-1 cell line as an in vitro model. BSFLM treatments were assessed through four assays: oxidative stress mitigation under H₂O₂ exposure, baseline cellular proliferation, proliferation under protein-standardized conditions, and recovery from serum starvation. Each assay was carried out in three independent experiments with three replicates per treatment, and changes in coloration were quantified using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). The results showed that BSFLM from plant-based substrates, particularly MX and KW diets, significantly (p < 0.05) improved cell viability across all assays. Under oxidative stress, MX (121.1% ± 5.9) and AW (119.9% ± 6.1) treatments maintained viability levels comparable to Vitamin C (119.3% ± 3.8) (250 ppm of DSM Stay-C) and the control (137.5% ± 11.6). In proliferation assays, MX (207.6% ± 16.3) and KW (196.3% ± 11.1) outperformed animal-based treatments AO (122.6% ± 4.4) and AS (113.1% ± 3.7), and these effects persisted under protein-standardized conditions, although the statistical significance was reduced. In the recovery from serum starvation assay, cells treated with MX (45.5% ± 1.9) and KW (42.0% ± 0.4) exhibited markedly higher viability than AS (15.5% ± 1.9) and AO (14.8% ± 2.2). The biochemical composition of BSFL reared on different substrates, including proximate, amino acid, fatty acid, and polyphenol profiles, was analyzed to contextualize the observed cellular responses. These findings highlight the superior functional properties of BSFLM derived from plant-based substrates and support its potential use as a targeted functional feed ingredient in aquaculture feed formulations. Full article

Autophagy is a central pathway involved in maintaining cellular homeostasis during development, metabolism, and regeneration. The selective autophagy receptor p62/SQSTM1 is a multifunctional protein that plays a critical role in regulating autophagic activity by interacting with LC3/Atg8 proteins and ubiquitinated substrates. Aedes albopictus has rapidly spread worldwide and poses a serious threat to human health by transmitting dengue and other arboviral diseases. In the present study, we identified a putative p62/SQSTM1 homolog protein (AaSQSTM1) in Ae. albopictus, which contains conserved structural regions, including the Atg8 family interaction motif (AIM) and ubiquitin-associated (UBA) domain. The expression levels of AaSQSTM1 and AaAtg8 varied from the egg stage to the adult stage in Ae. albopictus. Quantitative analyses revealed that blood-feeding upregulated the expression levels of AaSQSTM1 and AaAtg8 in the ovaries of female adults. AaSQSTM1 was applied to monitor autophagic activity alone or with AaAtg8 by assaying endogenous protein levels and overexpressing fluorescent reporters in C6/36 cells. Our study revealed that AaSQSTM1 regulates the autophagic activity with AaAtg8, providing a basis for studying the autophagy process in mosquitoes. Full article

The cheese (or ham) skipper, Piophila casei (Linnaeus), belongs to the family Piophilidae and is a detritivore species that feeds on decaying organic matter. Its larvae are commonly found on high-protein substrates (including carcasses), with a life cycle that is strongly influenced by environmental temperature and food nature. In this study, we investigated development time and larval length of P. casei reared on Parma ham PDO (Protected Designation of Origin) at five constant temperatures (20, 22, 24, 26, 28 °C). We calculated the accumulated degree days (ADD) and constructed isomegalen- and isomorphen-diagrams to estimate the infestation time. The minimum development threshold (t_L) obtained by extrapolating the development rates measured between 20 °C and 28 °C was 9.91 °C, resulting in ADDs (oviposition–eclosion) of 216.9, 219.9, 220.7, 209.2, and 220.1 at 20, 22, 24, 26, and 28 °C, respectively. Full article

Due to its high content of lignocellulose, cotton stalk is difficult to degrade naturally and utilize effectively, so it is often regarded as waste. In this study, the effects of Pleurotus ostreatus XH005, Lactiplantibacillus plantarum LP-2, and cellulase enzyme on the cotton stalk substrate under aerobic solid-state fermentation (SSF) conditions were investigated, and the metabolites were analyzed to identify potential functional compounds in the cotton-stalk-fermented feed. Preliminary optimization results obtained through single-factor experiments were as follows: fermentation time 14 days, XH005 inoculum size 8.00% (v/m), material-to-water ratio 1:0.50 (v/m), LP-2 inoculum size 2.00% (v/m), and cellulase addition 0.60% (m/m). Based on these single-factor experimental results, XH005 inoculum size, LP-2 inoculum size, material-to-water ratio, and cellulase addition were selected as independent variables. Through response surface methodology (RSM) optimization experiments, 29 experimental groups were designed. Subsequently, based on Box–Behnken analysis of variance (ANOVA) of lignin and cellulose content, along with contour and response surface plots, the optimal aerobic solid-state fermentation parameters were determined as follows: fermentation time 14 days, XH005 inoculum: 7.00% (v/m), material-to-water ratio: 1:0.55 (v/m), LP-2 inoculum: 2.00% (v/m), and cellulase enzyme addition: 0.65% (m/m). Results showed that compared with the control group (CK), the optimized group exhibited a 27.65% increase in lignin degradation rate and a 47.14% increase in cellulose degradation rate. Crude protein (CP) content increased significantly, while crude fiber (CF), detergent fiber and mycotoxin contents decreased significantly. Non-targeted metabolic analysis indicated that adding cellulase and inoculating Pleurotus ostreatus XH005 and Lactiplantibacillus plantarum LP-2 in aerobic SSF of cotton straw feed produced functionally active substances such as kaempferol (C343), carvone (C709) and trilobatin (C604). Therefore, this study demonstrates that microbial-enzyme co-action SSF significantly enhances the nutritional composition of cotton stalk hydrolysate. Furthermore, this hydrolysate is suitable for the production of functional compounds, endowing the fermented feed with health-promoting properties and enhancing the utilization of cotton processing byproducts in the feed industry. Full article

Organic-waste-derived volatile fatty acids (VFAs) are promising substrates for fungal biomass cultivation, offering a nutrient-rich medium capable of meeting microbial growth requirements. However, the growth and biomass productivity are highly influenced by the VFAs’ composition and mode of operation. This study investigated the cultivation of Aspergillus oryzae fungal biomass using agro-industrial-derived VFA effluent, employing repeated-batch and fed-batch (stepwise and continuous-feeding) cultivation modes to evaluate fungal growth and biomass composition. The highest dry biomass yield of 0.41 dry biomass/gVFAs_fed (g/g) was achieved in fed-batch mode with continuous feeding, where the biomass exhibited pellet morphology, facilitating ease of harvesting. The crude protein content varied according to the cultivation strategy, reaching 45–53% in continuous-feeding fed-batch mode, while it was 34–42% in stepwise fed-batch mode. Additionally, the fungal biomass contained significant levels of essential macronutrients and trace elements, including Mg, Ca, K, Mn, and Fe, which are crucial if the biomass is intended to be used in animal feed formulations. This study highlights the effects of cultivation modes on biomass composition and the potential of VFA-derived fungal biomass as a sustainable feed ingredient. Full article

Dark fermentation (DF) has gained increasing interest over the past two decades as a sustainable route for biohydrogen production; however, understanding how reproducible the process can be, both from macro- and microbiological perspectives, remains limited. This study assessed the reproducibility of a parallel continuous DF system using fruit-vegetable waste as a substrate under strictly controlled operational conditions. Three stirred-tank reactors were operated in parallel for 90 days, monitoring key process performance indicators. In addition to baseline operation, different process enhancement strategies were tested, including bioaugmentation, supplementation with nutrients and/or additional fermentable carbohydrates, and modification of key operational parameters such as pH and hydraulic retention time, all widely used in the field to improve DF performance. Microbial community structure was also analyzed to evaluate its reproducibility and potential relationship with process performance and metabolic patterns. Under these conditions, key performance indicators and core microbial features were reproducible to a large extent, yet full consistency across reactors was not achieved. During operation, unforeseen operational issues such as feed line clogging, pH control failures, and mixing interruptions were encountered. Despite these disturbances, the system maintained an average hydrogen productivity of 3.2 NL H₂/L-d, with peak values exceeding 6 NL H₂/L-d under optimal conditions. The dominant microbial core included Bacteroides, Lactobacillus, Veillonella, Enterococcus, Eubacterium, and Clostridium, though their relative abundances varied notably over time and between reactors. An inverse correlation was observed between lactate concentration in the fermentation broth and the amount of hydrogen produced, suggesting it can serve as a precursor for hydrogen. Overall, the findings presented here demonstrate that DF processes can be resilient and broadly reproducible. However, they also emphasize the sensitivity of these processes to operational disturbances and microbial shifts. This underscores the necessity for refined control strategies and further systematic research to translate these insights into stable, high-performance real-world systems. Full article

Pectins are high-value plant cell-wall polysaccharides with extensive applications in the food, pharmaceutical, textile, paper, and environmental sectors. Traditional extraction and processing methodologies rely heavily on harsh acids, high temperatures, and non-renewable solvents, generating substantial environmental and economic costs. This review consolidates recent advances across the entire Bacillus–pectinase value chain, from green pectin extraction and upstream substrate characterization, through process and statistical optimization of enzyme production, to industrial biocatalysis applications. We propose a practical roadmap for developing high-efficiency, low-environmental-footprint enzyme systems that support circular bioeconomy objectives. Critical evaluation of optimization strategies, including submerged versus solid-state fermentation, response surface methodology, artificial neural networks, and design of experiments, is supported by comparative data on strain performance, fermentation parameters, and industrial titers. Sector-specific case studies demonstrate the efficacy of Bacillus pectinases in fruit-juice clarification, textile bio-scouring, paper bio-bleaching, bio-based detergents, coffee and tea processing, oil extraction, animal feed enhancement, wastewater treatment, and plant-virus purification. Remaining challenges, including enzyme stability in complex matrices, techno-economic scale-up, and structure-guided protein engineering, are identified. Future directions are charted toward CRISPR-driven enzyme design and fully integrated circular-economy bioprocessing platforms. Full article

The predatory mite Amblyseius andersoni Chant (Acari: Phytoseiidae) is a key biological control agent against spider mites and other pests. For its broad application, efficient and affordable mass-rearing systems are essential. This study evaluated the effects of rearing substrate, food type, and rearing history on the development, survival, reproduction, and predation efficiency of the predator. Mites were reared on leaf discs or Plexiglas plates and fed one of five diets, including various plant pollens and the stored product mite Carpoglyphus lactis (L.) (Acari: Carpoglyphidae). Additionally, it was assessed whether rearing five generations on cattail pollen supplemented with the natural prey (Tetranychus urticae Koch (Acari: Tetranychidae) or frozen C. lactis influenced later predators’ performance. The substrate type did not affect development or survival contrary to the food source, with mites fed on cattail pollen or C. lactis developing faster and producing more eggs. Survival remained high across all diets. The intrinsic rate of increase was highest with cattail pollen and C. lactis. The five-generation rearing did not affect performance or feeding on natural prey such as T. urticae or Aculops lycopersici (Tryon) (Acari: Eriophyidae). These findings demonstrate that A. andersoni can be effectively mass-reared on alternative diets and substrates, supporting biocontrol strategies. Full article

The drastic surge in Sardine landings in Korea underscores the urgent need for sustainable upcycling strategies. However, research on the feasibility of using sardine (SD) in food waste (FW)-based substrates during the cultivation of black soldier fly (Hermetia illucens) larvae (BSFL) remains limited. Thus, we aimed to investigate the effect of incorporating varying SD contents (0, 25, 50, 75, and 100%), into which 4-day-old (third-instar) larvae weighing approximately 0.02 g were introduced and reared for 12 days in triplicate. SD inclusion in the substrate had a dose-dependent effect on BSFL growth; higher concentrations (≥50%) markedly inhibited key growth indices, including a significant reduction in total biomass (p < 0.05). Incorporating SD into the diet dose-dependently enriched the biomass with eicosapentaenoic acid and docosahexaenoic acid while reducing the relative proportions of saturated and monounsaturated fatty acids (p < 0.05). Proteobacteria and Firmicutes were the dominant phyla in the intestinal microbiota of BSFL. Further, SD inclusion altered the gut microbial community structure. Increased SD concentration in the diet led to a progressive reduction in unique genera, indicating decreased microbial diversity at higher inclusion levels. Overall, incorporating SD into FW for BSFL cultivation is feasible; however, optimizing substrate composition—particularly moisture and nutrient balance—is necessary to enhance larval growth and productivity. Full article

Energy security fosters the development of biogas, particularly in the context of the rapid energy transition. Substrates suitable for anaerobic digestion serve as feedstocks to produce biogas. Determining the optimal feedstock ratio is a key factor for achieving viable anaerobic digestion (AD) processes with high methane yields. This study evaluated different two-stage AD assays using biomass from a leguminous crop (Lupinus Albus, lupin) and olive mill wastewater (OMW). The highest methane yields were obtained in assays with higher proportions of lupin in the feed mixture (532 L kg VS⁻¹ and 522 L kg VS⁻¹) and at a higher Organic Load Rate (OLR) evaluated (510 L kg VS⁻¹). Moreover, the presence of OMW in the feedstock significantly increased the Volatile Fatty Acid (VFA) concentration, as observed in the assay. Full article

As global aquaculture is on the rise, the demand for sustainable and high-quality feed ingredients is intensifying. Black soldier fly larvae (BSFL) meal has emerged as a promising alternative to traditional fishmeal due to its favorable nutritional profile, waste recycling potential, and low environmental impact. This review explores the novel role of BSF meal in aquafeeds, highlighting its effects on fish growth performance, feed efficiency, and fillet quality. Furthermore, the antimicrobial and immune-boosting properties of lauric acid and chitin are discussed. However, despite its promise, several challenges still hinder the large-scale adoption of BSFL meal in aquaculture. These include regulatory restrictions on substrates, concerns over fish meat quality and safety, consumer acceptance, and the economic and logistical hurdles of industrial-scale BSFL farming. This paper synthesizes current scientific findings and regulatory frameworks, identifies key gaps in knowledge, and discusses the potential of BSFL meal as a sustainable alternative in aquafeeds while addressing its challenges. Full article

Water-resistant antifogging hard coatings possessing self-healing properties were successfully prepared by applying N,N-dimethylformamide solutions containing the mixtures of carboxy-functionalized polysilsesquioxane (PSQ-2C) with oligo(ethylene glycol)s (OEGs; n = 2–6 and n = 2–4) at the feed functional group ratios (carboxy groups in PSQ-2C/hydroxy groups in OEG) of 10:1 and 4:1, respectively, onto oxygen plasma–treated glass substrates, followed by heat drying, water immersion, and room-temperature drying. The formation of ester bonds in the resulting coatings, indicating the presence of a cross-linked structure, was confirmed via Fourier-transform infrared/attenuated total reflectance spectroscopy. Notably, the coating prepared using PSQ-2C and tetraethylene glycol (OEG; n = 4) at a feed functional group ratio of 10:1 demonstrated no peeling or dissolution even after water immersion for 1 h, and its surface hardness, which was evaluated via the pencil scratch test, was 4H. Additionally, when exposed to water vapor generated from warm water at 40 °C at a distance of 2 cm, the coating maintained transparency for up to 85 s, confirming its excellent antifogging performance. Finally, the coating exhibited self-healing properties, as evidenced by the disappearance of scratches induced by a 5H pencil when the coating was left standing at 25 °C and 30% relative humidity for 5 min. Full article