Search Results (512)

Background/Objectives: The escalating crisis of antibiotic resistance and the inherent limitations of conventional antibiotics necessitate the development of innovative therapeutic strategies. Targeted drug delivery (TDD) offers a powerful approach to enhance efficacy, minimize systemic toxicity, and circumvent bacterial resistance. This systematic review aims to evaluate the potential of unique bacterial transport systems (BTSs), surface specific receptors and intracellular enzymes as platforms for TDD via the “Trojan Horse” strategy (THS). Methods: A comprehensive literature review was conducted, focusing on studies that investigated the specificity and mechanisms of BTSs responsible for the uptake of metabolites that are essential for and unique to bacteria. This includes an analysis of transport systems for siderophores, bacteria-specific sugars, cell wall components, D-amino acids, and vitamins. We assessed preclinical and clinical examples of drug conjugates utilizing these pathways, as well as emerging platforms such as bacteriophage-derived proteins, antibody–antibiotic conjugates, and bacterial extracellular vesicles (EVs). Results: BTSs demonstrate high specificity for their cognate substrates, providing effective molecular gateways for TDD of drugs photosensitizers and diagnostic probes in form of conjugates. The siderophore–cephalosporin conjugate cefiderocol represents a clinically validated example, having received FDA approval. Preclinical studies further reveal that conjugates utilizing sugars (e.g., maltose, trehalose) and vitamins (e.g., B12) can significantly enhance antibiotic uptake and activity against both Gram-positive and Gram-negative pathogens, including drug-resistant strains. Emerging platforms like bacteriophage endolysins and engineered EVs show promise for overcoming biological barriers such as bacterial outer membranes and intracellular host niches. Conclusions: The THS leveraging BTSs represents a clinically viable and promising avenue for next-generation antibacterial therapies. Advantages of BTS include overcoming bacterial resistance, such as reduced membrane permeability and efflux pumps, enabling the “revival” of antibiotics that are poorly permeable or toxic, increasing their local concentration at the target site and reducing side effects on host cells. While significant progress has been made, a striking disconnect persists between the hundreds of conjugates demonstrating potent in vitro activity and the limited agent that has achieved clinical use. This in vitro–in vivo gap reflects, in large part, the early stage of this field rather than a fundamental failure. Further research is critically needed not only to identify novel BTSs and optimize drug-linker chemistry, but also to systematically address the translational barriers—including poor pharmacokinetics, immunogenicity, and unexpected toxicity—that have prevented most promising candidates from advancing beyond preclinical evaluation. Full article

Alpha-linolenic acid (ALA) is an essential omega-3 fatty acid and a vital component in food applications. In this study, we investigated a range of physicochemical culture conditions—including pH, temperature, and carbon source—to evaluate biomass and ALA accumulation in Chlorella sp. L166 and its mutant, C-12. The study aimed to identify favorable culture conditions and evaluate the feasibility of using diluted bean curd (tofu) wastewater as a low-cost medium. Under mixotrophic cultivation, ALA content was determined via GC-MS, and the removal efficiencies of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) were simultaneously monitored. The results showed that L166 achieved its highest ALA accumulation at pH 6.0 and 23 °C with maltose. C-12 exhibited appropriate ALA accumulation at pH 7.0 and 23 °C with maltose and reached its maximum biomass at pH 8.0 and 25 °C with glucose. After 8 days of cultivation in threefold-diluted tofu wastewater, C-12’s ALA content reached 6.1 mg/g, significantly higher than that observed in BG11 medium. Meanwhile, both strains removed 81.2–83.2% of TN, 35.7–36.0% of TP, and 42.6–43.5% of COD. This study provides preliminary data on the effects of culture conditions on microalgal ALA production, highlighting the potential for future practical applications of C-12. Full article

The emergence of multidrug-resistant Pseudomonas strains poses a serious threat to public health. Essential oil components, such as thymol (TH), exhibit potent antibacterial activity. However, the effects of continuous sublethal TH exposure and resulting changes to antibiotic susceptibility remain poorly understood. Here, we investigated a multi-resistant Pseudomonas psychrophila strain after TH adaptation using an integrated transcriptomic and metabolomic approach. Treatment with TH caused a significant decrease in MIC values for aminoglycosides (streptomycin, gentamicin, kanamycin) and tetracycline and increased susceptibility to five other antibiotics. Multi-omics analyses revealed coordinated changes in fatty acid metabolism (FabI downregulation and accumulation of unsaturated fatty acids), lipid A biosynthesis (LpxC downregulation), peptidoglycan synthesis (Mur genes downregulated, accompanied by increased spermine levels), and stress response pathways (such as GABA, GadA, maltose, and MalK). These results suggest that metabolic alterations and envelope remodeling potentially affect cell wall integrity and growth, which could, in turn, contribute to increased antibiotic susceptibility and re-sensitization. Overall, our findings highlight the potential of TH-mediated sensitization as a complementary strategy to restore antibiotic efficacy. Full article

Gold nanoparticles (AuNPs) have numerous applications in science and industry. Therefore, their potential phytotoxicity should be investigated. Garden cress (Lepidium sativum L.) is a useful model plant for assessing the effects of chemicals released into the environment. The aim of this study was to prepare alginate gels containing AuNPs for plant exposure experiments, evaluate their physicochemical properties, and determine their effects on selected biochemical parameters of garden cress seedlings. Gold nanoparticles were synthesized in sodium alginate at an initial concentration of 50 mg/L, using xylose and maltose as reducing agents. The gels were diluted with distilled water to obtain AuNP concentrations of 5 and 25 mg/L. Garden cress seeds were placed on filter paper soaked with the tested formulations, while distilled water and sodium alginate solutions without AuNPs served as controls. After 5 days of incubation at 20 °C under light conditions, the plant material was collected and selected bioactive compounds were determined. AuNP-containing gels significantly affected the biochemical status of the seedlings. In particular, AuNPs synthesized with xylose at 25 mg/L significantly increased the contents of photosynthetic pigments and total polyphenolic compounds. All tested AuNP formulations increased the antioxidant activity of seedlings, suggesting the activation of abiotic stress-related defense responses, however, direct markers of oxidative damage were not assessed in the present study. Overall, the results indicate that alginate-based AuNPs can modify selected biochemical parameters in garden cress seedlings, and these effects depend on nanoparticle concentration and reducing sugar used during synthesis, which may be relevant for the future development of plant-targeted nanomaterials for agricultural applications. Full article

Thermotolerant methylotrophic yeast Ogataea parapolymorpha is a promising host for high-temperature bioprocesses, yet the effects of carbon source and exogenous carbohydrates on their heat response remain poorly understood. We investigated how growth on glucose, glycerol, or methanol, short-term thermoadaptation (45 °C, 2 h), and supplementation with trehalose, sucrose, maltose, or xylose affect thermotolerance (55 °C, 30 min) and intracellular trehalose content. Thermoadaptation increased survival on all carbon sources and was accompanied by substantial trehalose accumulation in glucose- and glycerol-grown cells, but only minor trehalose accumulation in methanol-grown cells. Carbohydrate supplementation improved survival only in methanol-grown cultures. Under these conditions, trehalose, sucrose, and maltose increased intracellular trehalose levels, whereas xylose enhanced survival without a comparable increase in trehalose. These results show that the heat-stress response of O. parapolymorpha is strongly carbon source-dependent and that the protective effects of carbohydrate supplementation in methanol-grown cells cannot be explained by trehalose accumulation alone. Full article

Texture characteristics are critical quality evaluation indicators for soft foods. Traditional texture profile analysis (TPA) relies on probe–sample contact and may cause irreversible structural damage, limiting its application in nondestructive or online detection. In this study, a non-contact and nondestructive Controlled Airflow–Laser Texturemeter (CAFLT) system was developed to achieve rapid multi-parameter texture characterization. The system integrates programmable airflow loading with laser displacement sensing to implement a TPA-like double-cycle loading protocol, simultaneously acquiring time–applied airflow pressure (T–AP) and time–displacement (T–D) responses. Gelatin–maltose composite gels with graded Bloom strengths (CL50–CL250) were used as model samples. Texture-related descriptors were extracted using a dual-curve feature framework and compared with traditional TPA measurements. The CAFLT system produced a double-peak response pattern resembling that of traditional TPA and showed clear monotonic trends with increasing gel strength. Hardness_CAFLT exhibited a strong correlation with the reference TPA hardness value (r = 0.97). In addition, Gumminess_CAFLT showed a positive association with traditional gumminess (r = 0.87), but should be interpreted within the CAFLT-specific loading framework. Multivariate principal coordinates analysis further demonstrated clear multivariate discrimination among samples. Additionally, the time-domain descriptor t_Peak1 showed a strong power-law relationship with Bloom strength ($R^2=0.96$), indicating enhanced sensitivity to mechanical differences under small-deformation conditions. Overall, the CAFLT system provides a feasible approach for non-contact, nondestructive, and quantitative texture evaluation of soft foods, and shows strong potential for real-time quality monitoring and intelligent food inspection. Full article

Polyethylene terephthalate (PET) waste accumulation requires sustainable recycling alternatives. While Ideonella sakaiensis PETase offers a green solution, its industrial application is hindered by low solubility and poor thermostability. In this study, we systematically evaluated the synergistic effects of maltose-binding protein (MBP) fusion and periplasmic translocation strategies to optimize PETase production in Escherichia coli. Our results demonstrate that MBP acts as a potent solubilizing partner for PETase, with the cytosolic MBP–PETase variant achieving a high purification yield of 8.4 mg per gram of wet cell weight–a significant improvement over the PelB–PETase control (1.1 mg per gram of wet cell weight). Furthermore, the periplasmic MalE–MBP–PETase construct provided an optimal intermediate compromise between the yield, thermal stability, and catalytic activity by leveraging the oxidative environment of the periplasm for critical disulfide bond formation. Although PelB–PETase exhibited higher specific activity, its low yield limits industrial scalability. This study establishes a robust plug-and-play platform for high-throughput PET depolymerization, providing a foundational step toward a circular plastic economy. Full article

Chinese yam (Dioscorea opposita Thunb.) is a nutrient-rich tuber with recognized health benefits, yet its application in beverage products remains limited due to processing and formulation challenges. In this study, a sequential fermentation strategy was adopted, using Saccharomyces bayanus followed by Lactobacillus brevis to enhance microbial viability and metabolic activity in Chinese yam juice. Samples were collected as an unfermented control (CY), yeast-fermented juice (SP), and sequentially fermented juice (LB). Microbial analysis showed that sequential fermentation supported high LAB viability, reaching 8.92 log CFU/mL in LB, accompanied by a progressive decrease in pH from 5.67 (CY) to 4.27 (LB). Untargeted LC-MS/MS metabolomics identified 1442 metabolites and revealed distinct shifts in the metabolic composition of CY, SP, and LB, indicating stage-dependent modifications of metabolic pathways. Targeted analyses confirmed substantial depletion of sucrose and maltose during fermentation, while trehalose accumulated from undetectable levels in CY to 5.23 mg/g in SP and 7.49 mg/g in LB. Organic acid profiling demonstrated marked increases in lactic and succinic acids, consistent with microbial carbohydrate metabolism. Total phenolic and flavonoid contents increased by 58% and 30%, respectively, while antioxidant capacity (DPPH, ABTS, and FRAP) improved by up to 120% after sequential fermentation. The final fermented beverage (LB) contained a low ethanol concentration of 0.8% (v/v). Sensory evaluation indicated that sequential fermentation improved the overall flavor, aroma, and acceptability of the Chinese yam juice. These findings demonstrate that sequential fermentation with S. bayanus and L. brevis effectively enhances the bioactive composition and antioxidant potential of Chinese yam juice, supporting its development as a functional fermented beverage. Full article

This study aimed to valorize by-products from cabbage processing to produce nutrient-rich powders that are suitable for food incorporation and, as a case study, to evaluate their application in texture-modified jelly intended for senior consumers. Freeze-dried powders from cabbage leaves and cores were analyzed for physicochemical properties, nutritional value, and antioxidant activity. Steaming significantly affected water absorption, solubility, and color: powders from fresh cabbage exhibited higher water solubility and lighter, greener hues, whereas powders from steamed cabbage showed darker, yellow–red tones due to pigment degradation. Nutritional analysis confirmed high dietary fiber contents (>30 g/100 g dry weight) in all powders. Core powders contained more potassium and phosphorus, with minimal mineral losses being observed after steaming. Sugar profiling showed greater fructose, glucose, and total sugar contents in leaf powders, whereas sucrose predominated in core powders. Steaming facilitated maltose formation. Although steaming generally reduced total phenolic content, it increased antioxidant activity in steamed leaf powders. Application trials demonstrated that cabbage powder concentrations strongly influenced jelly composition, including dietary fiber, total phenolic content and mineral levels, while pectin concentration primarily affected texture. Optimized formulations yielded nutritionally enriched jellies with acceptable sensory properties, demonstrating the feasibility of using cabbage processing by-products as a value-added food ingredient. Full article

As consumer attitudes shift, non-alcoholic and low-alcohol beers (NABLABs) have grown rapidly in popularity. This has driven interest in biological production methods that avoid the cost and flavor damage associated with post-fermentation dealcoholization. This review focuses on how barley wort composition and process conditions shape the metabolism of maltose- and maltotriose-negative non-Saccharomyces yeasts (NSYs), and how this, in turn, affects ethanol yield, flavor, and aroma in NABLABs. Key sections examine differences in carbohydrate utilization between Saccharomyces and NSYs, the influence of oxygen and Crabtree/Kluyver effects on carbon flux, and the roles of glycerol and organic acid formation as alternate carbon sinks that also contribute to mouthfeel, sweetness perception, and acidity. Particular attention is given to mashing strategies and enzyme additions used to redesign wort sugar profiles for NSYs, including high-temperature, low-gravity mashes and exogenous amyloglucosidase to increase glucose while limiting maltose and ethanol formation. The review also summarizes how the NSY-driven production of esters, higher alcohols, and the biotransformation of hop-derived precursors can offset excessive sweetness and “worty” off-flavors that commonly affect NABLABs. The use of NSYs opens an exciting array of opportunities for brewers to make NABLABs; however, challenges remain. Saccharomyces yeasts have centuries of brewing experience behind them and the adaptations needed for effective use of NSYs are still in development. Fundamentally, the challenge for NABLAB brewers using biological methods is to balance the desirable effects of fermentation while maintaining ethanol levels below the target threshold. This review outlines those challenges in detail and examines some of the approaches that are being used to solve them. Full article

This study aimed to investigate the flavor quality and starch physicochemical properties of three orange-fleshed sweet potato varieties commonly cultivated in northeastern China. Fresh and baked samples were evaluated using sensory analysis, electronic nose and tongue, gas chromatography-mass spectrometry for volatile compound profiling, and chemical methods for starch characterization. Liankaoshu 1 exhibited the highest sensory score (88.6), reflecting superior taste and aroma. A total of 70 volatile organic compounds were identified, including β-damascenone, maltol, and β-ionone, as key contributors to baked flavor. Significant varietal differences were found in starch content, particle size, and crystalline structures, with Pushu 32 showing CA-type crystals, Yanshu 25 A-type, and Liankaoshu 1 B-type. Baking increased maltose and soluble sugar levels, which were strongly correlated with sensory attributes. Spearman correlation analysis revealed that sweetness and overall sensory scores were significantly and positively correlated with maltose, soluble sugar, and reducing sugar contents, as well as starch particle size parameters (p ≤ 0.05). These results indicate that starch structural characteristics and saccharification efficiency play critical roles in regulating flavor formation during baking, providing a theoretical basis for sweet potato breeding and processing optimization. Full article

Edible mushrooms are an underexplored source of industrial proteases, whose synthesis is highly dependent on the cultivation substrate. This study investigated the effect of nine culture media on the proteolytic profiles of Auricularia sp., Lentinus sp., Macrocybe sp., and Grifola frondosa. Fungi were cultivated on diverse media (e.g., Czapek, Malt, Soy Flour). We analyzed total protein, specific activities (total, cysteine, serine proteases) using a biochemical assay, and protein secondary structure via FTIR, with metabolic patterns identified by PCA. A dissociation was found between total protein yield (highest in MFI/Casein media) and specific activity (highest in maltose media), suggesting catabolite repression. Distinct metabolic strategies emerged: Grifola frondosa specialized in serine protease production in the minimal Czapek medium (catabolic derepression), while Macrocybe sp. maximized cysteine protease production on soy flour (substrate induction). FTIR confirmed this, revealing a β-sheet-dominant (75.5%) structure for Grifola extract versus a random-coil-dominant (60.8%) structure for Macrocybe. This study provides a framework for mechanism-based bioprocess design, enabling the tailored production of serine proteases from G. frondosa (Czapek medium) or cysteine proteases from Macrocybe sp. (soy medium) for customized biotechnological applications. Full article

Background/Objectives: Intestinal α-glucosidases, including maltase, sucrase, and trehalase, are key enzymes responsible for the final steps of carbohydrate digestion. Although Thai medicinal plants possess diverse bioactivities, most previous studies on plant-derived α-glucosidase inhibitors have focused on single-enzyme assays, primarily maltase, and lack systematic comparison of the three major intestinal disaccharidases—maltase, sucrase, and trehalase. This study aimed to determine the kinetic properties of rat intestinal α-glucosidases and evaluate the inhibitory potential of selected Thai plant extracts. Methods: Rat small-intestinal S9 fractions, post-mitochondrial supernatant obtained by centrifugation at 9000× g, containing soluble enzymes and microsomal components responsible for disaccharidase activity, were prepared and disaccharidase activities were quantified using the glucose oxidase–peroxidase method. Kinetic parameters were obtained from Eadie–Hofstee plots using maltose, sucrose, and trehalose as substrates. Fourteen Thai plant extracts (Oryza sativa, Cratoxylum formosum, Garcinia cawa, Aganosma marginata, Polyalthia evecta, Ellipeiopsis cherrevensis, Ancistrocladus tectorius, Micromelum minutum, and Microcos tomentosa) and isolated compounds (Bergapten, Eurycomalactone, Lupinifolin, Osthole) were assessed at 100 and 250 µg/mL for inhibition of maltase, sucrase, and trehalase. Results: Maltase exhibited the highest substrate affinity based on the lowest Km value. Among the tested samples, the 80% ethanol extract of Microcos tomentosa (MT80) inhibited maltase, sucrase, and trehalase activities by approximately 10–60% at 250 µg/mL, and was the only extract showing consistent inhibition across all three enzymes. Other extracts showed selective inhibition toward one or two enzymes. Conclusions: These findings indicate that MT80 possesses a broad-spectrum inhibitory profile against major intestinal α-glucosidases, suggesting a potential advantage for comprehensive regulation of postprandial glucose excursions and supporting its candidacy as a source of novel α-glucosidase inhibitors. Full article

Dissolvable microneedles (DMNs) represent an innovative approach to patient-friendly drug delivery, eliminating the need for conventional hypodermic injections. This study reports on the fabrication, Confocal Laser Scanning Microscopy (CLSM)-based optical visualization of drug distribution, and mechanical characterization of maltose-based DMNs impregnated with lignocaine, a local anesthetic. Microneedles were fabricated using a micro-molding technique and dried for nine hours. Structural integrity was evaluated using Field Emission Scanning Electron Microscopy (FESEM); drug distribution was examined via CLSM; and mechanical strength was assessed using nanoindentation. The FESEM results showed uniform microneedle formation with sharp tips and smooth surfaces, averaging 435 µm in height and 116 µm in width, with no significant dimensional variability (p > 0.5). CLSM analysis indicated even distribution of lignocaine throughout the matrix. Mechanical testing showed that each microneedle withstood 0.6 N, surpassing the 0.1 N threshold required for skin insertion. These results support the viability of maltose-based DMNs for local anesthetic delivery, with implications for outpatient, pediatric, and self-administered care settings. Future investigations will include Franz diffusion and in vitro dissolution studies to examine release kinetics. Full article

This study investigated the effects of germination on gamma-aminobutyric acid (GABA), free sugars, organic acids, polyphenols, protein content, and antioxidant activity in six legumes (mung beans, Dobrudzha beans, white beans, brown lentils, red lentils and chickpeas). Seeds were germinated for 5 days at room temperature, with or without an initial freezing pretreatment at −18 °C for 20 h. Daily analysis revealed significant increases in GABA across all legumes, especially chickpeas, which showed an 18-fold rise to 210.5 mg/100 g dry weight (DW), alongside elevated glutamate decarboxylase activity. Total polyphenols increased 3.4-fold in white beans and chickpeas by day five. Antioxidant activity (ORAC) rose in parallel, reaching 123.8 and 83.3 µmol TE/g DW in germinated white beans and chickpeas, compared to 68.4 and 45.4 µmol TE/g DW in non-germinated controls. While protein content remained stable, levels of free sugars (notably maltose) increased during germination. Organic acids rose across all samples as well, with quinic acid being the most abundant and showing the sharpest increase. Initial freezing had a clear effect on enhancing GABA accumulation compared to non-treated seeds, but generally exerted neutral effects on other bioactive components. Overall, germination triggered biochemical transformations in seeds, enriching them with bioactive compounds and enhancing their nutritional and functional properties, with chickpeas emerging as a particularly rich source of GABA, polyphenols, and organic acids, supporting their potential in functional food development. Full article