Search Results (271)

Glycine betaine transport systems are widely exploited by bacteria to survive osmotic stress and represent potential entry routes for antimicrobial delivery. Here, we investigate the bactericidal glycine betaine analog Tox-GB and its uptake, intracellular fate, and antimicrobial activity in Escherichia coli K-12 under osmotic stress. We show that the xenobiotic enters cells via a hierarchical uptake route involving the osmotically regulated compatible solute transporters ProU and ProP, ABC- and MFS-type transporters, respectively. ProU functions as the primary high-affinity transporter at low concentrations, whereas ProP provides a secondary uptake route at somewhat higher substrate levels. Loss of either transporter confers partial resistance, while simultaneous inactivation of both systems causes full resistance, underscoring their functional redundancy and the robustness of Tox-GB import. Intracellularly, Tox-GB undergoes oxygen-dependent degradation, yielding 4-nitrobenzaldehyde and dimethylglycine. While 4-nitrobenzaldehyde contributes to toxicity under aerobic conditions, Tox-GB remains bactericidal under anaerobic conditions, indicating additional oxygen-independent mechanisms involving either the parent compound or unidentified metabolites. These findings suggest a complex intracellular fate and multifactorial mode of action. Despite initial promise as a Trojan horse antimicrobial strategy, the use of Tox-GB for practical applications faces key limitations. Resistance readily emerges via transporter inactivation, and intrinsic resistance occurs in species lacking appropriate compatible solute uptake systems. Structural constraints in glycine betaine transporters further restrict design flexibility. Osmotic regulation limits activity to specific niches, and potential host toxicity stemming from reactive metabolites raises safety concerns. Collectively, these findings highlight the mechanistic complexity and translational challenges faced by glycine betaine–derived xenobiotics as antimicrobial agents. Full article

Sports nutrition products are increasingly expected to deliver bioactive compounds that aid in recovery, reduce fatigue, and support physiological regulation, going beyond merely providing energy and nutrients. However, many bioactive compounds face challenges such as poor aqueous dispersibility, limited stability, low bioaccessibility, or inefficient absorption, which hinder their practical use in real food products. This review critically examines food-grade, gel-based delivery systems for bioactive compounds in sports nutrition from a design-driven perspective. It focuses on hydrogels, microgels, emulsion gels, protein gel matrices, and multicomponent gel architectures that prioritize structural stability, digestion-triggered responsiveness, and compatibility with food. Key design principles are discussed, including the need to maintain stability during processing and storage, balance protection with release, and tailor delivery structures to sports-specific constraints such as gastrointestinal tolerance, osmotic load, nutrient timing, and changes in digestion related to exercise. The review also analyzes the effectiveness of gel-based and hybrid systems in liquid, solid, and semi-solid sports nutrition products, emphasizing how the product format and consumption scenario can influence delivery performance. A design decision framework is proposed to align bioactive properties, food format, target release profile, and exercise-stage requirements with appropriate delivery architectures. Current challenges are also addressed, including difficulties in predicting structure–function relationships, limited robustness during scale-up processes, and inadequate functional evaluation. Overall, gel-based food delivery systems provide a promising solution for improving the stability, release behavior, and practical functionality of bioactives in sports nutrition. Full article

Selenium (Se) biofortification is a promising approach to improve the nutritional value and functional quality of microgreens, although species-specific responses to Se remain insufficiently understood. This study investigated the effects of Se biofortification on physiological status, antioxidant responses, phenolic composition, and molecular changes in four Brassica microgreens: broccoli, kohlrabi, pak choi, and kale, using biochemical analyses, HPLC, and FTIR spectroscopy. The indicators of nutritional quality and stress-related metabolism in Brassica microgreens showed species-specific responses due to selenium treatment. Kohlrabi showed coordinated osmotic and metabolic adjustment involving osmolyte accumulation and enhanced antioxidant response, although moderate membrane sensitivity was observed at the highest selenium concentration. Pak choi maintained tolerance through balanced metabolic adjustment and enzymatic defense, while broccoli responded predominantly through enzymatic antioxidant mechanisms. Kale exhibited pronounced non-enzymatic responses, including anthocyanin accumulation and enhanced radical scavenging capacity. PCA confirmed species-specific response strategies and differential associations among biochemical parameters. Changes in antioxidant functionality were associated with both metabolite accumulation and structural reorganization of phenolic-related compounds. Overall, Se biofortification improved functional and nutritional traits of the investigated Brassica microgreens, although higher selenium concentrations induced moderate oxidative and membrane-related stress in certain Brassica microgreens. These findings highlight the importance of species-specific optimization of Se application to maximize crop quality while minimizing potential effects of Se toxicity. Full article

Red dragon fruit (Hylocereus polyrhizus), also referred to as pitaya, is an exotic fruit rich in macro- and micro-nutrients, including powerful natural antioxidants, that brings numerous benefits to human health, mostly for the control and management of the oxidative stress. Therefore, it has a great potential for industrial exploitation aimed at maximizing the extraction of its high-value bioactive compounds, specifically betacyanins (red pigments) and phenolics, for the production of functional foods, beverages, and health products. This aim of this study was to evaluate the production of high-quality concentrated red dragon fruit juice by using an integrated membrane system based on a combination of ultrafiltration (UF) and osmotic distillation (OD) processes capable of effective, but still mild concentration of valuable juice. Specifically, after juice extraction, the raw juice was preliminarily clarified by UF and then concentrated by OD up to 41 and 50 °Brix using dehydrate calcium chloride brine as the osmotic agent. The performance of UF and OD membranes was investigated under selected operating and hydrodynamic conditions. In addition, the impact of the integrated process on the quality of clarified and concentrated juices was assessed in terms of physicochemical properties and antioxidant activity. Physicochemical parameters and antioxidant activity were largely preserved after concentration, demonstrating the effectiveness of the proposed process in maintaining the nutritional, organoleptic, and nutraceutical properties of the juice. Full article

Foodborne diseases present a serious public health challenge, causing roughly 600 million illnesses and 420,000 deaths annually. A significant portion of this impact is felt in Asia, where traditional fermented and dry-salted seafood, such as katsuobushi, budu, and peda, are dietary staples. These products rely on diverse microbial communities that determine their final safety, flavor, texture, and shelf life. Historically, research has centered on lactic acid bacteria (LAB), yet the functional contributions of non-LAB halotolerant species, including genera like Tetragenococcus, Staphylococcus, and Bacillus, are functionally important in these high-salinity niches. This review evaluates the transition from basic taxonomic surveys to mechanistic multi-omics approaches, integrating genomics, transcriptomics, proteomics, and metabolomics to decode microbial functionality under selective environmental pressures. We discuss how genomic mining using platforms such as BAGEL4 and antiSMASH can uncover biosynthetic gene clusters and antimicrobial peptides, while CARD supports antimicrobial resistance monitoring. Transcriptomic analysis reveals microbial responses to osmotic stress, low water activity, and pH fluctuations, whereas proteomic profiling links gene expression to active enzymes, stress proteins, and functional biomarkers. Metabolomics captures the chemical outcomes of fermentation, including amino acids, volatile organic compounds, spoilage markers, and biogenic amines. By merging these high-dimensional datasets with artificial intelligence, researchers can move toward predictive modeling that distinguishes biological causation from simple correlation. This shift offers a strategy to improve the safety, consistency, and resilience of traditional high-salinity fermented seafood systems. Full article

Background/Objectives: Achillea millefolium is a well-known medicinal plant recognized in several pharmacopeias, while the Balkan endemic species Achillea clypeolata lacks a pharmacopeial monograph and remains insufficiently studied despite its traditional use. This study aimed to comparatively evaluate the phytochemical composition and biological potential of both species. Methods: Chemical composition was studied using UHPLC-MS/MS, HPLC, and FT-IR; anti-inflammatory potential was analyzed by erythrocyte membrane stabilization assay (heat- and hypotonicity-induced hemolysis); and enzyme-inhibitory activity was tested against collagenase, elastase, hyaluronidase, and tyrosinase. In addition, antioxidant activity was evaluated using DPPH, ABTS, and DCFDA assays; antimicrobial activity was determined using the broth microdilution method; and cytotoxic potential was investigated by the MTT assay. Results: The major constituents in water–ethanolic extracts were quinic acid derivatives, flavonoids, phenolic acids, and coumarins, with chlorogenic acid, 3,5-dicaffeoylquinic acid, cosmosiin, cynaroside, rutin, and hyperoside as dominant in both species. Extracts exhibited marked anti-inflammatory activity, where A. millefolium provided greater protection under heat-induced hemolysis, and both extracts showed comparable efficacy under osmotic stress. Concentration-dependent inhibition of collagenase, elastase, hyaluronidase, and tyrosinase (concentration from 62.5 to 1000 µg/mL), along with significant antioxidant activity in ABTS and DPPH assays, was observed. In MRC-5 cells, the extracts reduced AAPH-induced ROS levels up to 50 µg/mL, while higher concentrations showed diminished effects. Moderate cytotoxicity was observed, with A. clypeolata displaying stronger effects at 50–100 µg/mL. Both Achillea species exhibited broad-spectrum antimicrobial activity, with pronounced effects against Gram-positive bacteria. Conclusions: The results support the traditional use of Achillea species and highlight A. clypeolata as a promising, yet underexplored, source of bioactive compounds for dermatological and pharmaceutical applications. Full article

Lemongrass (Cymbopogon citratus) essential oil is mainly composed of the acyclic monoterpene aldehydes geranial (α-citral) and neral (β-citral), collectively known as citral, which exhibit documented cytotoxic activity against cancer cell lines, as well as geraniol and limonene, among other monoterpenoids. In a previous study we reported that the constituents of the essential oil (EO) composition of lemongrass in vitro plants were modulated by different types of cytokinins (CKs) exogenously added to the culture medium. However, in that work, EO components were detected as volatile headspace compounds by SPME-GC/MS rather than as bulk oil extracts directly injected to GC/MS. Therefore, in this study, EOs were extracted by hydrodistillation from plants micropropagated with different CKs (BAP or 2iP) under different osmotic conditions (MS 3/3 and MS 5/5) and subsequently established in a greenhouse. Analysis of EO in C. citratus plants showed that plants grown on MS-3/3 BAP had more α-citral, and plants grown on MS-5/5 2iP had more limonene. This study demonstrates the impact of various CKs on EO production in lemongrass. The findings showed that 5/5 2iP produced the highest limonene yield, indicating a potential yield of 100 mL from 8719 plants. Similarly, 101 plants under the 5/5 Ctrl treatment are required for 100 mL of citral, and 34 plants under the 5/5 Ctrl treatment are required for 100 mL of geranyl acetate. The 5/5 2iP requires 816 plants to produce 100 mL of geraniol, and it takes 11,340 plants to produce 100 mL of β-caryophyllene from the 3/3 2iP treatment. Full article

This study presents a thermodynamic analysis of the dissociation and association behavior of the Fe–Si system using the Bjerrum–Guggenheim osmotic coefficient. An equilibrium thermodynamic approach was applied to evaluate the Gibbs free energy, equilibrium constant, and degree of association of the congruently melting compound FeSi over a wide temperature range. The Fe–Si system was analyzed across three characteristic crystallization regions: Fe-rich, FeSi, and Si-rich. It was established that the Fe-rich region exhibits behavior approaching ideality with a nearly linear dependence of the osmotic coefficient, whereas the Si-rich region is characterized by strong deviations from ideality due to intensive association processes. The FeSi crystallization region represents a transitional regime in which association and dissociation processes occur simultaneously. The formation and partial dissociation of [Fe_xSi_y] clusters significantly affect the thermodynamic behavior of the melt. It was shown that accounting for FeSi dissociation leads to a linearization of the osmotic coefficient dependence and improves the accuracy of thermodynamic description. The proposed analytical approximations demonstrate high correlation coefficients (R² ≈ 0.99), confirming the reliability of the developed approach. The results provide a consistent thermodynamic framework for describing phase transformations and structural evolution in Fe–Si melts and can be applied to the optimization of metallurgical processes involving silicon-containing alloys. Full article

Background: Anoectochilus roxburghii (Wall.) Lindl. is an endangered medicinal herb, and salt stress has been reported to promote the accumulation of bioactive secondary metabolites. Central carbon metabolism plays a key role in carbon allocation in plants; however, the integrated molecular and metabolic responses of A. roxburghii to salt stress remain largely unclear. Method: In this study, an integrated transcriptomic and metabolomic approach was employed to investigate the reprogramming of central carbon metabolism in A. roxburghii under 50, 100, and 200 mM NaCl treatments. Results: Metabolomic analysis revealed a significant accumulation of soluble sugars, which suggests enhanced osmotic adjustment and alteration in energy metabolism. Transcriptomic profiling identified 7019 upregulated and 5192 downregulated DEGs, with pathways related to the TCA cycle, galactose metabolism, and fructose/mannose metabolism predominantly upregulated, while oxidative phosphorylation was suppressed. Integrative transcriptome–metabolome profiling further identified key genes associated with oxaloacetate and fructose-6-phosphate, suggesting a coordinated regulation between central carbon metabolism and polysaccharide biosynthesis. Conclusions: Collectively, these findings demonstrate that salt stress induces coordinated metabolic and transcriptional reprogramming in A. roxburghii, driving carbon flux reallocation from growth-related processes toward osmoprotective metabolism. This provides a mechanistic basis for the enhancement of bioactive compounds under moderate stress and offers insights for improving both salt tolerance and medicinal quality in saline environments. Full article

Shoot tip cryopreservation is essential for the long-term conservation of plant genetic resources. It provides the only reliable method for establishing a long-term, readily available gene pool of clonally propagated crops and elite in vitro clones used in the pharmaceutical, food, and cosmetic industries. Still, its success is often limited by the inherent sensitivity of many species to the osmotic and chemical stresses imposed by concentrated cryoprotectant (vitrification) solutions and severe dehydration. The optimization of modern cryopreservation protocols primarily focuses on modifying shoot tip preculture, cryoprotectant treatments, or regrowth conditions, while frequently overlooking donor plant preconditioning or relegating it to a secondary role. However, the physiological state of in vitro plants from which apical or axillary shoot tips are extracted may hold the key to successful post-cryopreservation recovery, especially in cryo-sensitive taxa. This review revisits the critical role of donor plant vigor and induced stress tolerance in the cryopreservation of clonal crops by systematically evaluating preconditioning strategies, including cold acclimation, sucrose pretreatment, and the use of growth regulators and signaling molecules such as abscisic, jasmonic, and salicylic acids, involved in stress signaling and tolerance development. The beneficial physiological changes induced by donor plant pretreatment, such as reduced freezable water content and the accumulation of protective compounds, are discussed in the context of contemporary cryopreservation methods. The effects of culture conditions, including the roles of ammonium and nitrates, light quality, culture density and aeration, medium strength, culture age, and subculture duration, are also considered. We analyze how different treatments of in vitro donor plants improve shoot tip tolerance to osmotic and/or chemical toxicity imposed by specific cryopreservation methods to support a material-centered selection of a cryopreservation procedure. Future directions and potential approaches for integrating target donor plant preconditioning into modern cryopreservation protocols for shoot tips, particularly in stress-sensitive species, are discussed. Full article

Sweet potato (Ipomoea batatas (L.) Lam) is an important food and energy crop. Soil salinization is a major abiotic stress that limits agricultural productivity and severely reduces yield of crops. Protein hydrolysates, as a class of natural biostimulants, have gained increasing attention for their potential to improve crop yield, quality and stress tolerance. This study investigated the effects of peptides from swine blood (PSB) on high salinity stress tolerance in sweet potato. Application of PSB promoted the growth of both aerial and underground parts of sweet potato under normal and high-salinity conditions. Further analysis revealed that, under high salinity stress, exogenous PSB up-regulated the expression of genes associated with stress responses, increased the accumulation of organic osmotic adjustment compounds such as free amino acids, promoted K⁺ uptake to elevate the K⁺/Na⁺ ratio, and enhanced the activity of key antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) involved in the reactive oxygen species-scavenging system. These biochemical responses contributed to maintaining cellular osmotic balance and redox homeostasis, protecting the cell membrane from damage while preserving its structural integrity and normal physiological functions, and improving photosynthetic efficiency, thereby enhancing high salinity stress tolerance in sweet potato. Thus, PSB holds significant potential as an effective natural biostimulant for sweet potato cultivation in saline soils. Full article

Salinity stress severely limits barley production by disrupting physiological and biochemical processes critical for growth and yield. Although numerous studies have examined individual physiological or antioxidant responses to salinity, an integrated multivariate understanding of how these mechanisms collectively contribute to yield stability at the flowering stage remains limited. This study aimed to elucidate the integrated antioxidant and physiological mechanisms underlying salinity tolerance in barley genotypes during flowering. Barley plants were subjected to controlled salinity treatments, and a comprehensive set of phenolic compounds, antioxidant capacity indices, physiological traits, and yield components were measured. Multivariate analyses, including redundancy analysis (RDA) and partial least squares regression (PLSR), identified key traits contributing to yield stability under salinity. Multivariate analyses revealed also genotype-specific physiological strategies underlying contrasting salinity tolerance levels. Antioxidant defenses, such as total phenolics, DPPH and ABTS radical scavenging activities, and α-tocopherol, along with osmotic regulators like proline and soluble sugars, were closely associated with improved water status and reduced oxidative damage. These coordinated responses correlated strongly with yield components, including thousand-grain weight and main spike seed number. Notably, this study provides new insights into the predictive relevance of selected biochemical and physiological markers for yield performance under salt stress using PLSR at the flowering stage. PLSR further demonstrated the high predictive power of a limited subset of biochemical and physiological markers for yield traits under salt stress. Collectively, these findings reveal that the interplay between antioxidant machinery and osmotic adjustment at flowering is critical for barley resilience to salinity, providing valuable physiological markers to inform breeding strategies aimed at improving salt tolerance. Full article

Modern agriculture is increasingly challenged by fungal diseases, with phytopathogens such as Fusarium species causing substantial yield and quality losses in major crops globally. Although synthetic fungicides remain widely used, their intensive application raises serious concerns regarding environmental safety, human health, and the rapid emergence of resistant pathogen populations in the environment. These limitations have accelerated the search for sustainable, biologically based alternatives. In this context, Bacillus species isolated from saline and hypersaline habitats have emerged as a distinctive and still underexplored group of microorganisms with dual functionality as biological control agents (BCAs) and plant growth–promoting rhizobacteria (PGPRs) in salt-affected agroecosystems. Their novelty lies in their combined ability to suppress phytopathogens, enhance plant growth, and tolerate or mitigate salinity stress. Owing to their exceptional metabolic adaptability, these bacteria remain active under osmotic stress and produce a wide range of bioactive compounds that collectively contribute to their antifungal activity and improved plant performance. This review critically synthesizes advances published over the last six years (2019–2025), providing a comprehensive overview of the current understanding of the mechanisms underlying the biocontrol potential of halophilic/halotolerant Bacillus species against Fusarium spp. and other fungal phytopathogens. Particular emphasis is placed on ecological adaptations, molecular mechanisms, and the dual roles of these bacteria as BCAs and PGPR. The exploration and exploitation of saline-adapted Bacillus strains offer promising, eco-friendly, and cost-effective strategies for managing Fusarium diseases, thereby contributing to resilient and sustainable agricultural systems under increasing environmental constraints in the future. Full article

Red blood cells represent a widely used cellular model in cytotoxicity studies, particularly in hemocompatibility assessments. As enucleated cells, which are abundant and easily accessible in both humans and animals, red blood cells allow for rapid, reproducible, and low-cost evaluation of the toxicity of bioactive compounds, whether natural, synthetic, or nanoparticulate. From a functional perspective, the red blood cell membrane is highly sensitive to physical and chemical environmental changes (osmolarity, temperature, pH, and the presence of oxidizing agents). This sensitivity makes red blood cells an effective biosensor for detecting membrane damage, hemolysis, oxidative stress, methemoglobin formation, and aggregation processes. Therefore, in vitro tests using red blood cells allow for the preliminary evaluation in preclinical development, particularly for the early screening of cytotoxicity, membrane-disruptive effects, and hemocompatibility of small molecules, nanomaterials, and blood-contacting biomaterials. These techniques include hemocompatibility tests, evaluation of oxidative and osmotic damage, and evaluation of erythrocyte aggregation and function. However, the use of red blood cells as a cytotoxicity model also has significant limitations. As anucleate cells, erythrocytes lack organelles such as nuclei, mitochondria, or lysosomes, which prevents the evaluation of their effects on key intracellular processes such as protein synthesis, cell signaling, apoptosis, or endoplasmic reticulum stress. This lack of cellular complexity limits their usefulness as a sole model in studies of systemic toxicity or tissue-specific cytotoxicity. These tools offer an effective preliminary approach to anticipating risks in biomedical and pharmacological research. Full article

Understanding how plant physiological traits respond to environmental variation is essential for explaining plant performance in alpine ecosystems. Based on field sampling along an elevational transect on the Tibetan Plateau, we quantified osmotic adjustment compounds, antioxidant indicators, and plant hormones in leaves of different species to examine interspecific differences in sensitivity to temperature and precipitation to characterize patterns of physiological plasticity among alpine plants. Along the elevational gradient, declining temperature results in increasing cold stress, whereas lower elevations are associated with reduced precipitation and intensified drought stress. Temperature primarily influenced plant physiological trait expression by promoting growth-related physiological processes, while precipitation variability mainly regulated traits associated with water stress. The three dominant alpine meadow species exhibited distinct patterns of physiological plasticity: Poa litwinowiana showed coordinated regulation of growth and defense pathways, whereas Carex moorcroftii and Carex parvula displayed more conservative response strategies, with physiological regulation tending to maintain homeostasis rather than strongly activating stress responses. These interspecific differences in physiological regulation were significantly associated with variations in plant height, cover, and dominance, providing trait-level physiological insights relevant to plant performance. Full article