Search Results (391)

Bacterial biofilms are structured microbial communities enclosed within a self-produced extracellular polymeric substance matrix composed of polysaccharides, proteins, extracellular DNA, and lipids. This matrix promotes adhesion, structural stability, and the development of heterogeneous microenvironments that restrict antimicrobial penetration and shield bacteria from host immune responses. As a result, biofilms are major contributors to chronic, recurrent, device-related, and difficult-to-treat infections, posing a major challenge for clinical management and antimicrobial stewardship. This review summarizes current understandings of biofilm biology, its clinical relevance, including the stages of biofilm development, the composition and protective roles of the matrix, and the physiological heterogeneity that arises during maturation. It also examines key mechanisms underlying biofilm tolerance and resistance, such as limited antibiotic diffusion, and sequestration, enzymatic inactivation, efflux pump upregulation, persister cell formation, and horizontal gene transfer. In addition, it highlights important clinical settings in which biofilms are implicated, including cystic fibrosis, chronic wounds, osteomyelitis, implant- or device-associated infections, and breast implant illness, in which persistent implant-associated biofilms and the resulting chronic inflammatory milieu have been hypothesized to contribute to local and systemic manifestations in a subset of patients. The review further discusses conventional and emerging approaches for biofilm detection alongwith real-time monitoring. Biofilm-associated infections remain difficult to eradicate because persistence is driven by multiple interconnected protective mechanisms. Effective management therefore requires integrated strategies that combine accurate detection with multifaceted therapies, including antibiotics alongside matrix-disrupting enzymes, quorum-sensing inhibitors, bacteriophages, metabolic reactivators, and nanotechnology-based delivery systems. Advances in multi-omics and system-level modeling will be essential for developing next-generation strategies to prevent, monitor, and treat biofilm-associated disease. Full article

Although teixobactin, a promising cyclic undecadepsipeptide, exhibits efficacy against Gram-positive bacteria due to its novel mode of action and low potential for resistance, its clinical application is limited by two key shortcomings: ineffectiveness against Gram-negative bacteria and poor penetration of the protective extracellular polymeric substance (EPS) in biofilms. This renders it unsuitable for targeting the polymicrobial biofilms, which are the cause of periodontitis and peri-implantitis. We designed a modified teixobactin analog by integrating rhamnolipid, Ag@Fe₃O₄ nanoparticles, and _L-Chg₁₀-teixobactin to obtain a novel magnetic nanoparticle (MNP). The MNP demonstrates the ability to simultaneously degrade EPS, penetrate biofilm structures, and eliminate both G⁺ and G^- pathogens under a rotating magnetic field (RMF). Rhamnolipid grafting degraded 52.5% of biofilm EPS. MNPs showed broad-spectrum antimicrobial activity, with minimal inhibitory concentrations from 100 to 200 µg/mL. Combined with RMF, biofilm eradication rates reached 97.0% (E. faecalis), 97.7% (S. gordonii), 88.4% (P. gingivalis), and 74.2% (F. nucleatum). The biofilm thickness was reduced from 19.4 ± 2.9 µm to 7.4 ± 1.0 µm, and the biofilm biomass was reduced by 68.5%. This combined strategy integrates enzymatic EPS degradation, magneto-mechanical disruption, and dual antimicrobial action, offering a promising topical therapy for periodontitis and peri-implantitis. Full article

Background and Objectives: While nisin exhibits promising antitumor properties, its clinical utility is hindered by pharmacokinetic instability and rapid enzymatic degradation. This systematic review evaluates the critical role of advanced pharmaceutical formulations and targeted nanosystems in overcoming these limitations to enhance nisin’s cytotoxic and pro-apoptotic efficacy in vitro. Methods: Following PRISMA guidelines, a comprehensive search was conducted across six electronic databases (PubMed, ScienceDirect, Scopus, Web of Science, SpringerLink, and DOAJ). In vitro studies comparing free nisin against polymeric, metallic, and cyclodextrin-based nanocarriers across diverse neoplastic lineages were included. Methodological quality was assessed using the SciRAP 2.1 tool, and a within-line comparative analysis was performed for MDA-MB-231 and HT-29 models. Results: Twelve studies met the inclusion criteria. A definitive technological inflection point was identified: nisin-loaded nanosystems reduced effective concentrations by up to 2706-fold relative to the free peptide in MDA-MB-231 cells, and 71-fold in A549 lung cancer cells. Mechanistically, nanosystems facilitated membrane pore formation, mitochondrial-mediated apoptosis via Bax/Bcl-2 modulation, caspase 3/7/9 activation, and p53 reactivation. Three previously underreported mechanistic dimensions were identified: TWIST1 downregulation and FZD7 binding in hepatocellular carcinoma, and downregulation of CEA, CEAM6, MMP2F, and MMP9F in colorectal cancer lines. Conclusions: The therapeutic viability of nisin in oncology is strictly dependent on pharmaceutical engineering. Future research must prioritize in vivo pharmacokinetic validation, experimental confirmation of novel mechanistic targets, and standardized nisin purity reporting to consolidate its clinical translation. Full article

Antimicrobial peptides (AMPs) have re-emerged as promising anti-infective agents, particularly against multidrug-resistant bacteria; however, their therapeutic development remains constrained by proteolytic degradation, host cell toxicity, and rapid systemic clearance. Rather than focusing solely on sequence discovery, recent efforts have shifted toward structural and supramolecular modification strategies aimed at improving stability, selectivity, and pharmacological performance. This review critically analyzes intramolecular modifications—including phosphorylation, glycosylation, acetylation, methylation, and backbone cyclization—that modulate peptide conformation and resistance to enzymatic degradation. In parallel, extramolecular approaches such as PEGylation, lipidation, and conjugation to antibiotics, siderophores, or antibodies are examined in the context of enhanced targeting and prolonged bioavailability. Particular emphasis is placed on localized delivery systems, including hydrogels, polymeric films, and nanofibrous scaffolds, which enable spatially controlled administration and mitigate systemic exposure. By integrating evidence from ex vivo and in vivo infection models, this work delineates the translational potential and remaining bottlenecks of chemically engineered AMP platforms for skin and soft tissue infections. Full article

Sorghum (Sorghum bicolor L.) is an environmentally friendly crop known for its nutritional and bioactive properties. This study investigated the effects of sorghum on the antioxidant properties and consumer acceptance of nurungji, a traditional Korean snack. To understand the antioxidant contribution of ferulic acid in sorghum during non-enzymatic browning, the antioxidant activity of ferulic acid was evaluated using a sugar (glucose or fructose)–lysine Maillard reaction model system. Nurungji samples were prepared with varying sorghum blending ratios (SN0, SN25, SN50, SN75, and SN100) and heating durations (0, 1, 3, and 5 min). The total polyphenol and total flavonoid contents of nurungji increased significantly in a sorghum concentration- and heating duration-dependent manner. Antioxidant activities, including DPPH and ABTS radical scavenging activities, ferric reducing antioxidant power (FRAP), and reducing power, exhibited trends similar to those of the antioxidant components. In the isolated model system, the addition of ferulic acid significantly enhanced the antioxidant capacity of the Maillard reaction products (MRPs), with the fructose–lysine–ferulic acid solution exhibiting the highest activity. These results support the proposed mechanism that during the thermal processing of nurungji, complex polymeric phenolic compounds within the sorghum are degraded, releasing free ferulic acid that actively boosts the overall antioxidant properties of the resulting MRPs. Although the antioxidant properties of nurungji increased with higher sorghum concentration, the consumer acceptance evaluations indicated that SN0 and SN25 received significantly higher scores for overall acceptance, taste acceptance, and purchase intention (p < 0.05). Full article

This work aimed to explore novel polymeric material by synthesizing polyamide 6,5 via the direct enzymatic polycondensation of dimethyl glutarate and 1,6-Diaminohexane, using the lipase Novozym 435 as a biocatalyst. While maintaining a fixed monomer feed ratio, the effects of reaction temperature, duration, and enzyme concentrations on the molecular weight and yield of the resulting polyamide 6,5 were systematically investigated. The experimental results indicated that the optimal conditions for the Novozym 435-catalyzed synthesis were a reaction time of 3 days, a temperature of 90 °C, and enzyme concentrations of 20 wt%. The establishment of this enzymatic synthesis route for polyamide 6,5 not only provides a novel methodology for polymer synthesis but also offers a new perspective for the future green materials manufacturing industry. Full article

Polymers are fundamental components of modern pharmaceutical manufacturing, serving critical roles as excipients, binders, coatings, and matrices for controlled drug delivery systems. However, the conventional production of pharmaceutical polymers relies heavily on petrochemical feedstocks, energy-intensive processes, and hazardous solvents, leading to significant environmental and economic burdens. In recent years, increasing regulatory pressure, environmental awareness, and sustainability goals have driven the pharmaceutical industry toward greener manufacturing strategies. This review critically examines sustainable green polymer production for pharmaceutical applications, with a focus on both environmental and economic impacts. The review discusses the role of polymers in pharmaceutical manufacturing, outlines the limitations of conventional polymer synthesis, and highlights the relevance of green chemistry principles in addressing these challenges. Key green polymer synthesis techniques, including biopolymer production, enzymatic polymerization, microwave-assisted synthesis, supercritical CO₂ processing, and the use of ionic liquids and deep eutectic solvents, are systematically evaluated. Additionally, life-cycle assessment (LCA) approaches are explored to assess the environmental performance of green polymer processes in comparison with traditional methods. Beyond environmental sustainability, this review emphasizes the importance of pharmacoeconomic evaluation in determining the feasibility of adopting green polymers at an industrial scale. Cost–benefit analyses, manufacturing cost comparisons, long-term economic advantages, and health–economic outcomes are discussed in the context of pharmaceutical supply chains. Regulatory perspectives, industrial implementation challenges, and future directions are also addressed. Overall, this review highlights sustainable polymer innovation as a critical pathway toward environmentally responsible, economically viable, and future-ready pharmaceutical manufacturing. Full article

To establish a biorefinery within kraft-pulp mills, the extraction of fermentable sugars must be balanced with the preservation of fiber quality for papermaking. This study investigates this trade-off by applying partial enzymatic hydrolysis to unbleached high-kappa eucalyptus kraft pulp to co-produce bioethanol and packaging-grade materials. Although the mass-transfer limitations inherent to the high-consistency strategy (15% solids or 150 g L⁻¹) restrict extensive saccharification (keeping glucose conversion below 5% at 1.5 h), it naturally directs the process toward a low-severity regime essential for fiber conservation. Structural analysis (X-ray diffraction and microscopy) revealed that enzymes preferentially targeted amorphous regions, increasing crystallinity (from ≈74% to ≈82%) but reducing intrinsic fiber strength (tear) over time (dropping from ~5.6 to ~2.3 mN·m²·g⁻¹ within 30 min). However, a strategic window for valorization has been identified. Instead of direct papermaking, hydrolyzed residue is highly effective as a strength-enhancing additive. When blended (20% w w⁻¹) with commercial pulp, the modified fibers improved interfiber bonding, restored the tensile strength, and significantly increased the Burst Index (up to ~1.7 kPa·m²·g⁻¹). These results demonstrate a viable industrial approach using partial hydrolysis to recover hemicellulose-based sugars for biofuels, while transforming the solid fraction into a high-performance reinforcement agent for paper packaging. This approach effectively converts a potential trade-off into a synergistic dual-product stream. Full article

Background: There is growing interest in plant-derived compounds for managing vascular diseases. Veratramine (VRT), a steroidal alkaloid isolated from plants of the Veratrum genus, exhibits diverse biological effects such as antihypertensive, analgesic, and antitumor activities, yet its influence on hemostasis and thrombus formation has not been characterized. This investigation sought to determine whether VRT exerts anticoagulant effects using integrated in vitro and murine models. Methods: VRT’s anticoagulant profile was comprehensively evaluated using integrated biochemical, cellular, and murine models, including clotting time assays (aPTT/PT), chromogenic enzymatic assays, fibrin polymerization analysis, platelet aggregometry, and endothelial modulation of PAI-1/t-PA under inflammatory conditions. Results: VRT treatment significantly prolonged both intrinsic and extrinsic coagulation times, directly inhibited enzymatic activities of thrombin and FXa, and attenuated their generation by endothelial cells. Additionally, VRT interfered with fibrin clot formation and diminished agonist-induced platelet aggregation. Ex vivo coagulation analyses confirmed its anticoagulant action, while endothelial studies revealed a reduced PAI-1/t-PA ratio following VRT exposure. Conclusions: These data establish VRT as possessing novel direct dual inhibition of thrombin and FXa alongside suppression of fibrin polymerization, platelet reactivity, and PAI-1 expression—positioning it as a promising multifunctional anticoagulant agent. While preclinical murine models preclude direct clinical translation absent pharmacokinetic data, these findings warrant further mechanistic and translational investigation. Full article

This study investigates how wheat arabinoxylan (AX) structure influences its functional properties following enzymatic hydrolysis with wheat malt β-1,4-endoxylanase. Using three types of wheat AX with initial molecular weights of 489.42–602.42 kDa, arabinose-to-xylose (A/X) ratios of 0.49–0.55, and average degrees of polymerization (avDP) of 1223.57–1506.05 as substrates, enzymatic cleavage produced four high-purity fractions with reduced molecular weight (98.63–301.42 kDa), increased A/X (0.60–0.65), and lower avDP (246.59–753.56). Enzyme action led to triple-helix unwinding, especially at low avDP, accompanied by reduced storage modulus. Molecular weight was the key factor affecting water-holding capacity and foam stability, with high-molecular-weight AX showing superior performance due to its intact helical structure and higher viscoelasticity. In contrast, low-molecular-weight AX with high A/X ratios exhibited enhanced interfacial adsorption and free radical scavenging, supported by greater hydroxyl exposure and higher negative charge density (−9.23 mV). Its emulsifying activity and hydroxyl radical scavenging rate increased by 32.95% and 32.02%, respectively, compared to the original AX. These findings demonstrate that enzymatic modulation of AX molecular weight and branching can directionally tune its functionality, providing a theoretical basis for targeted applications in food systems. Full article

Triacetin (TA) is a solvent commonly used in pharmaceutical and food applications, and as a plasticizer in bioplastics such as poly(lactic acid) (PLA) and cellulose acetate (CA). L-lactide is the monomer used in the ring-opening polymerization of PLA. The structure of TA emulsions stabilized by a cellulose hydrogel (CH) was imaged in this study. The emulsions were prepared by mechanical homogenization or a two-step process with subsequent high-pressure homogenization (HPH). The two-step process yielded smaller TA droplets and a more homogeneous CH dispersion. The images demonstrate that emulsion stabilization is due to CH particles adsorbed at the TA–water interface. The ester hydrolysis of TA and a lactide/TA solution by two industrially important lipases, from Candida rugosa (CRL) and Burkholderia cepacia (BCL), was investigated, assessing the effect of CH as an emulsion stabilizer. Mechanically homogenized TA emulsions were effectively hydrolyzed. Lactide was found to inhibit the enzymatic hydrolysis of TA. This inhibition was mitigated by CH for CRL-catalyzed hydrolysis but not for BCL catalysis. These results indicate a synergistic effect of CH stabilization on the interfacial activation of CRL. Thise effect may also be relevant for the biodegradation of bio-derived plastics and their fibrous cellulose composites. Full article

In recent decades, lignocellulosic biomass has attracted increasing attention as a sustainable alternative to fossil-fuel-based resources. However, the compact and highly crystalline structure of cellulose remains a major limitation to its effective utilization. In this study, the allomorphic transformation of cellulose was induced through chemical treatments using sodium hydroxide (NaOH) and ethylenediamine (EDA), enabling the conversion of native cellulose I into cellulose II and cellulose III, respectively. The resulting changes in the crystalline structure were systematically investigated using X-ray diffraction and Raman spectroscopy. Both NaOH- and EDA-treated celluloses exhibited enhanced enzymatic digestibility compared to untreated cellulose, consistent with the observed modifications in the crystal structure. Nevertheless, some results indicate that crystalline structure is not an absolute determining factor, but rather one of several parameters, including specific surface area, particle size, and degree of polymerization. Full article

The biosynthesis of melanin in plants remains an enduring biochemical enigma. Unlike the well-characterized pathways of animals and fungi that produce the canonical “true melanins”, the enzymatic origins and physiological functions of melanin-like pigments in plants are poorly described. Recent advances in Juglans regia (walnut) have begun to illuminate this “dark metabolism,” revealing a dual polyphenol oxidase (PPO) system, constitutive JrPPO1 and stress-inducible JrPPO2, that orchestrates the oxidation of phenolics into amorphous, heterogeneous polymeric pigments. Functional studies demonstrate that JrPPO1 maintains tyrosine and redox homeostasis, while silencing triggers a lesion-mimic phenotype, highlighting the enzyme’s role in detoxifying reactive intermediates. In contrast, JrPPO2 responds to redox and pathogen stress, driving pigment formation as part of the defense response. The integration of biological evidence, encompassing genomics, genetics, and phenotyping, reveals that walnut pigmentation represents a genetically encoded, developmentally regulated adaptation balancing metabolic cost and oxidative protection. Decoding this system reframes melanin biosynthesis in plants as a strategic redox resilience mechanism, one that transforms potentially toxic phenolic oxidation into protective polymerization, bridging primary metabolism, defense, and evolution. Full article

Chitosan oligosaccharides (COSs), obtained through the hydrolysis of chitosan, exhibit remarkable antibacterial properties. In pursuit of COSs with enhanced antibacterial activity, the enzymatic characteristics of the chitosanase from Bacillus velezensis YB1534 (BvChi) were investigated. The purified BvChi displayed optimal activity at pH 6.0 and 50 °C and showed the highest hydrolytic activity using colloidal chitosan as a substrate, with the presence of Mn²⁺. The COSs produced by enzymatic hydrolysis of BvChi exhibited a minimum degree of polymerization (DP) of 2, and their antimicrobial activities against certain pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Salmonella typhi 50071, and Aeromonas hydrophila) were evaluated. Among them, the 20 min hydrolysate showed the strongest growth inhibition against all these pathogens, demonstrated by the inhibition zone diameters, and its MIC and MBC values toward A. hydrophila were 0.625 and 1.25 mg/mL, respectively. Thin-layer chromatography (TLC) analysis showed that the hydrolyzed products after 20 min contains more COSs with DP > 5. These findings highlighted the potential of BvChi as a biocatalyst for producing antimicrobial COSs, applicable in food preservation and biomedical fields. Full article

The recovery of extracellular polymeric substances (EPS) from activated sludge (AS) represents a promising strategy to transform wastewater treatment plants (WWTPs) into resource recovery facilities within a circular economy framework. In this study, EPS was extracted from an AS process in a full-scale WWTP, highlighting its catalytic and bioflocculant properties, which represent an innovation in the valorization of this biopolymer. The EPS was subsequently characterized in terms of polysaccharides, proteins, and enzymatic activities (amylase and lipase). The bioflocculation performance of the EPS was evaluated using activated sludge mixed liquor. Results showed that EPS recovery yields using 50 °C and 80 °C were 196.3 ± 38.2 mg EPS/g sludge and 283.5 ± 85.4 mg EPS/g sludge, respectively. Enzymatic assays confirmed amylase activity ranging from 100 to 350 U/g sludge according to the extraction temperature. Lipolytic activity (20 U/g sludge) was comparable to values reported in the literature for EPS from biological sludge. The addition of EPS significantly improved the sludge settling velocity (from 0.86 to 4.48 m/h) and the sludge volume index (from 118.6 to 35.5). However, EPS application also increased the resistance to filtration by 50% and reduced cellular respiration by approximately 40%. Overall, the findings demonstrate that EPS from activated sludge acts as an effective bioflocculant with relevant catalytic properties, highlighting its potential as a high-value biotechnological product while also pointing to operational challenges that require further optimization. Full article