Search Results (708)

Coniferyl alcohol and coniferyl aldehyde are precursors of lignin and are used in spices and the pharmaceutical industry. In this work, antioxidant, anticholinergic, antidiabetic, and antiglaucoma effects of coniferyl alcohol and aldehyde were evaluated and compared against the standards. To determine the antioxidant capacities of coniferyl alcohol and aldehyde, ABTS^•+, DMPD^•+ and DPPH^• scavenging abilities as well as cupric ion (Cu²⁺) reduction, ferrous ions (Fe²⁺) reduction and Fe³⁺-TPTZ reduction activities were studied. Butylated hydroxytoluene (BHT), ascorbic acid, α-Tocopherol, Trolox, and butylated hydroxyanisole (BHA) were used as the standard antioxidants. When the antioxidant effects of coniferyl alcohol and coniferyl aldehyde are compared to the standards, they exhibit significant antioxidant effects. In addition, it was determined that coniferyl alcohol and coniferyl aldehyde had a high degree of inhibition effect towards carbonic anhydrase (hCA) I and II isoforms purified from human erythrocytes, α-glycosidase, butyrylcholinesterase (BChE), acetylcholinesterase (AChE), and α-amylase as in vitro and in silico. Molecular docking studies revealed favorable binding affinities of coniferyl alcohol and coniferyl aldehyde toward all investigated enzymes, with key hydrogen bonding and π–π interactions identified at the active sites. The docking findings were found to be compatible with the in vitro enzyme inhibition results, supporting the proposed multi-target biological potential of both compounds. Molecular docking studies revealed favorable binding affinities of coniferyl alcohol and coniferyl aldehyde toward all investigated enzymes. Key hydrogen bonding and π–π interactions were identified within the active sites, particularly for AChE and hCA II. The docking results were consistent with the in vitro enzyme inhibition data, supporting their multi-target biological potential. Docking demonstrated that both compounds can effectively interact with the catalytic regions of the target enzymes. The identified binding modes and interaction patterns support the observed inhibitory activities and provide a molecular basis for their multi-target biological effects. Full article

Background/Objectives: Lavandula cariensis species is cultivated uncommonly in the western region of Turkey. The colloquial appellations avayianos, karabasi, and myra are used to refer to the L. cariensis plant. The essential oil of L. cariensis was studied for its potential antiglaucoma, antioxidant, antidiabetic, and acetylcholinesterase inhibitory effects. Methods: The inhibitory effect of the essential oil of L. cariensis on the acetylcholinesterase (AChE), carbonic anhydrase II (CA II), and α-amylase enzymes was determined. Therefore, chemical profiles of L. cariensis’ essential oil were identified using Gas Chromatography Mass Spectrometry (GC-MS) and as Chromatography with Flame Ionization Detection (GC-FID) analyses. Results: Camphor (39.73%), fenchone (19.49%), exobornyl acetate (6.81%), camphene (5.49%), and eucalyptol (5.49%) were the most abundant compounds in L. cariensis essential oil. Radical scavenging effect of the essential oil of L. cariensis was examined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC₅₀: 231.0 ± 0.094 μg/mL) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (IC₅₀: 7.45 ± 0.013 μg/mL) radicals. Also, the ferric ions (Fe³⁺), cupric ions (Cu²⁺), and Fe³⁺-2,4,6-tri(2-pyridyl)-S-triazine (TPTZ) complex reducing capabilities were studied. Additionally, essential oil of L. cariensis indicated a comparable level of inhibition towards hCA II (IC₅₀: 276.42 μg/mL), AChE (IC₅₀: 14.22 μg/mL), and α-amylase (IC₅₀: 475.63 μg/mL) enzymes. Conclusions: The evaluation of the antioxidant capabilities and enzyme inhibition profiling of the essential oil of L. cariensis will be made possible by this comprehensive study, which serves as a springboard for further research. The essential oil of L. cariensis demonstrated enzyme-inhibitory activities against target enzymes associated with Alzheimer’s disease, diabetes, and glaucoma. Also, this study’s in vitro inhibition suggests promising prospects. Full article

Luteolin and its derivative glycosides (cynaroside, orientin and isoorientin) are compounds with a flavonoid structure of plant origin. There are different studies in the literature on the antioxidant capacities of the structures and their inhibition effects on some enzymes. In this study, the antioxidant capacities of each structure were determined comparatively, and their inhibitory effects against enzymes associated with different diseases such as acetylcholinesterase, butyrylcholinesterase, α-glycosidase and α-amylase were evaluated by comparative investigation in vitro and in silico. Antioxidant capacities were determined for each structure by iron ions (Fe³⁺), cupric ions (Cu²⁺), Fe³⁺−Triphenyltetrazolium chloride (TPTZ) reduction methods and 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), N,N-dimethyl-p-phenylenediamine (DMPD) radical scavenging methods. According to the results obtained, it was determined that the antioxidant capacities of the structures were close to or better than butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trolox, α tocopherol and ascorbic acid, which are used as standard antioxidants. The results of the study, which was conducted to determine the inhibition effects of the structures on the determined enzymes, were found to coincide experimentally and theoretically. According to the inhibition results, the best inhibitors were found as orientin (IC₅₀: 27.729 nM) for the human carbonic anhydrase I (hCA I), cynaroside (IC₅₀: 18.24 nM) for the human carbonic anhydrase I (hCA II), isoorientin (IC₅₀: 1.93 nM) for the acetylcholinesterase (AChE), and cynaroside (IC₅₀: 6.41 and 7.15 nM) for the butyrylcholinesterase (BChE) and α-glycosidase enzymes. Additionally, absorption, distribution, metabolism, and excretion (ADME) profiles and toxicity assessments of the structures were determined in a virtual environment. Full article

Gao-shan-hong-jing-tian (GSHJT) Oral Liquid is a phytochemical-rich preparation derived from Rhodiola, yet its anti-hypoxic active constituents and molecular mechanisms remain poorly understood. This study aimed to identify the key anti-hypoxic phytochemicals in GSHJT Oral Liquid and clarify their mechanisms of action to support its potential use in managing acute mountain sickness (AMS). We first established and validated an HPLC method for quality control, then comprehensively profiled the chemical composition using LC-MS. Network pharmacology and molecular docking were applied to predict the core anti-hypoxic components, candidate targets and signaling pathways. The primary bioactivity was further verified through an in vitro carbonic anhydrase (CA) inhibition assay. A total of 71 constituents were identified, with kaempferol and ellagic acid emerging as the primary anti-hypoxic phytochemicals. These compounds target seven core proteins (SRC, PIK3R1, ESR1, EGFR, PTK2, IGF1R, and LYN) to regulate vascular tone, inflammation, oxidative stress, blood–brain barrier integrity, and cell survival under hypoxic conditions. By modulating pathways such as HIF-1α, PI3K/AKT, FAK/PTK2, SRC, and IGF1R, these phytochemicals ultimately influence the onset and alleviation of AMS. Enzyme inhibition assays demonstrated that kaempferol and ellagic acid inhibited CA with IC₅₀ values of 34.05 μM and 119.1 μM, respectively. Molecular docking further revealed that both compounds suppressed CA activity through a combination of hydrogen bonding and hydrophobic interactions, consistent with a zinc-bound water-anchoring mechanism. This study elucidates the phytochemical basis and molecular mechanism responsible for the anti-hypoxic effects of GSHJT Oral Liquid, providing scientific support for its potential application as a natural, plant-derived intervention for preventing and alleviating acute mountain sickness, providing scientific support for its potential application and offering a reproducible paradigm for the rational development of other Rhodiola-based phytomedicines, though further in vivo validation is required to confirm the anti-hypoxic efficacy. Full article

Background: Helicobacter pylori is a globally prevalent gastric pathogen associated with chronic gastritis, peptic ulcer disease, and gastric adenocarcinoma. Its persistence within the gastric niche is strongly linked to biofilm formation, contributing to immune evasion and antibiotic therapy resistance. Methodology: In the present study, we investigated the antibiofilm potential of capsaicin, a natural phytochemical derived from Capsicum species, against H. pylori using experimental and computational approaches. Results: Capsaicin treatment significantly reduced biofilm biomass (up to 75.66 ± 4.00%), metabolic activity (up to 61.23 ± 6.88%), and cell surface hydrophobicity in a dose-dependent manner. Microscopic analyses revealed disrupted biofilm architecture and diminished extracellular polymeric substance at higher concentrations. Molecular docking analysis revealed that capsaicin interacts with target H. pylori proteins (GTP cyclohydrolase II, α-carbonic anhydrase, and urease) through stable hydrogen bonds and hydrophobic contacts. Molecular dynamics simulations further supported the stability of these complexes and demonstrated reduced structural fluctuations upon ligand binding. Free energy landscape analysis suggested ligand-induced conformational alterations in α-carbonic anhydrase, indicating possible structural effects associated with capsaicin interaction. Conclusions: Overall, the findings provide insight into the antibiofilm activity of capsaicin against H. pylori and highlight its potential as a natural adjunct strategy for combating biofilm-associated persistence and antimicrobial resistance. Full article

Acute heart failure (AHF) causes abrupt hemodynamic disturbances, including reduced forward flow and venous congestion, which may extend beyond the heart and contribute to peripheral organ stress. Skeletal muscle may be particularly vulnerable to these changes, but the relationship between acute hemodynamic status and circulating markers of skeletal muscle stress and regulation remains unclear. We prospectively enrolled 35 men hospitalized with AHF and non-invasively assessed their cardiac index (CI) by impedance cardiography and right atrial pressure (RAP) by echocardiography. Plasma carbonic anhydrase III (CA3), creatine kinase-MM (CK-MM), lactate, myostatin, and follistatin were measured at admission, discharge, and 30 days after discharge. Patients were analyzed according to low CI, defined as CI < 2.2 L·min⁻¹·m⁻²; elevated RAP, defined as RAP ≥ 8 mmHg; and combined CI/RAP profiles. CA3 and CK-MM were higher in patients with low CI or elevated RAP and were highest in the low-CI/elevated-RAP profile. CA3 and lactate did not significantly change during follow-up, whereas CK-MM modestly increased at 30 days. Myostatin and follistatin were highest at admission and decreased after clinical stabilization. In this pilot cohort of men hospitalized with AHF, estimated lower perfusion and greater venous congestion were associated with higher circulating markers of skeletal muscle stress, while muscle regulatory myokines declined after stabilization. These findings suggest that skeletal muscle-related biomarkers may reflect peripheral consequences of acute hemodynamic disturbance in AHF and warrant further investigation in larger cohorts. Full article

Nitrite is a key environmental challenge in intensive shrimp aquaculture, adversely affecting physiological regulation and survival. Although tolerant Penaeus vannamei families have been established by selective breeding, the basis of family-level variation in tolerance has yet to be clarified. In this study, nitrite-tolerant and nitrite-sensitive families were compared using survival analysis, transcriptomics, targeted qPCR validation, physiological assays, and RNA interference of representative transport-related genes. Under nitrite exposure, the tolerant family exhibited significantly higher survival and a distinct gill transcriptional response, characterized by stronger induction of acid–base and ion-transport genes, including carbonic anhydrase 2 (CA2), the Na⁺/K⁺-ATPase subunits ATP1A and ATP1B, as well as several V-type H⁺-ATPase-related genes. These transcriptional changes were accompanied by elevated ATP content and Na⁺/K⁺-ATPase activity, improved hemolymph pH stability, and reduced nitrite accumulation in both gill and hemolymph. RNAi-mediated knockdown of CA2 or ATP1B attenuated the nitrite-induced transport response, decreased ATP content and NKA activity, exacerbated hemolymph acidification, promoted internal nitrite accumulation, and ultimately reduced shrimp survival under nitrite stress. Family-based validation further showed that the tolerant family displayed higher survival than the sensitive family in the dsEGFP group, whereas this advantage was markedly reduced after CA2 or ATP1B knockdown under nitrite stress. These findings highlight that strengthened branchial ion transport and acid–base regulation represent key physiological mechanisms underlying nitrite tolerance in resistant shrimp families. Full article

A new series of isoxazole-fused thiazole–oxazole derivatives (11a–n) was rationally designed and synthesised with the aim of developing potent carbonic anhydrase (CA) I and II inhibitors. The synthesis was achieved in five steps starting from 4-bromoacetophenone, involving key intermediates such as hydroxylamine hydrochloride, hydrazine hydrate, thioisocyanate, and various phenacyl bromide derivatives, using ethanol, triethylamine, tetrahydrofuran (THF), and dimethylformamide (DMF) as solvents. The synthetic route included the formation of a β-ketoester, isoxazole ester, hydrazine adduct, thiourea derivative, and, ultimately, a thiazole ring. The structures of the final compounds were confirmed by ¹H-NMR, ¹³C-NMR, IR spectroscopy, and elemental analysis. All compounds were examined as inhibitors of human carbonic anhydrase (hCA) I and II, and all of them inhibited hCA I and hCA II. Kinetic investigation results revealed that these compounds inhibited hCA I and hCA II in a non-competitive manner. To further explore the molecular basis of their inhibitory activity, in silico studies, including molecular docking and 300 ns molecular dynamics (MD) simulations, were carried out against both CA I and CA II isoforms. These simulations provided detailed insights into the dynamic behaviour, stability, and key binding interactions of the compounds within the enzyme active sites, supporting their potential as promising carbonic anhydrase inhibitors. Full article

Background/Objectives: Carbonic anhydrase I (CAI) is a zinc-dependent metalloenzyme whose inhibitor discovery requires both effective navigation of chemical space and explicit evaluation of coordination-credible binding hypotheses. We aimed to develop an interpretable and reproducible QSAR-to-structure workflow for CAI inhibitor discovery. The workflow links potency prediction with zinc-site plausibility and early developability to support decision-oriented prioritization of new CAI inhibitor candidates. Methods: CAI inhibitors were retrieved from ChEMBL (CHEMBL261) and modeled as $p{K}_i=9-{\mathrm{l}\mathrm{o}\mathrm{g}}_{10}(K_i [\mathrm{n}\mathrm{M}\left]\right)$. AlvaDesc v3.0.8 generated 4224 2D descriptors, which were reduced using train-only preprocessing, variance filtering, correlation pruning, and bagged-tree ranking to a top-100 panel. Five regressors (elastic net, CART, bagging, GB, and XGB) were benchmarked on a held-out test set. Potent ChEMBL seeds (K_i ≤ 10 nM) were used for a 90% 2D similarity PubChem expansion. Predicted hits were then externally validated using independently available PubChem CAI $K_i$ records. Ten novel candidates lacking CAI $K_i$ data were docked to CAI (PDB: 1AZM) via SwissDock AutoDock Vina in neutral and relevant anionic states, with pose selection constrained by a Zn-donor filter (Zn-N/O $\le 2.6$ Å). SwissADME was used to profile physicochemical space, alerts, and absorption/distribution proxies. Results: The bagging model showed the best test generalization ($R^2=0.646$; RMSE = 0.61; MAE = 0.45). PFI and SHAP converged on sulfur/heteroatom connectivity and polar–lipophilic organization as dominant potency drivers. PubChem expansion yielded 25,315 analogs and 233 candidates at predicted $p{K}_i\ge 8.0$; external validation on 145 CAI-measured hits gave $R^2=0.358$ (RMSE = 0.456; MAE = 0.320). Across 20 ligand/protomer docking runs, 12 produced canonical Zn-anchored poses (10 Zn-N; 2 Zn-O). SwissADME indicated consensus logP values from −0.65 to 3.21, 0/10 PAINS alerts, and predominantly favorable drug-likeness (8/10 with zero Lipinski violations), supporting tiered advancement. Conclusions: Integrating interpretable QSAR, external PubChem validation, coordination-aware docking, and SwissADME yields a practical triage framework for CAI inhibitor discovery. The resulting tiered shortlist identifies two Zn-N-anchored N-alkyl sulfamides (CIDs 103935964 and 112684680) and one Zn-O-anchored carboxylate control (CID 122367674) as highest-priority computational hypotheses for staged biochemical evaluation. Full article

Background/Objectives: The aim of this study was to investigate the effects of intraocular pressure (IOP)-lowering drops on the sublayers of the human tear film as assessed by a novel nanometer-resolution Tear Film Imager (TFI, AdOM, Israel). Methods: In a prospective, cross-sectional study, 98 eyes from 56 adult human subjects were imaged using the TFI. The dataset included data from 18 eyes from 12 subjects treated with preserved IOP-lowering drops and 80 eyes from 44 control subjects not under ocular hypotensive therapy. Subjects in the IOP treatment group used a variety of IOP-lowering medications, including prostaglandin analogs, beta-blockers, carbonic anhydrase inhibitors, alpha agonists, and combination drops. A linear mixed effects model was used to assess the association between IOP-lowering therapy and tear film (TF) metrics, controlling for age and intra-individual correlation. The following parameters were measured: muco-aqueous layer thickness (MALT), muco-aqueous layer thinning rate (MALTR), lipid layer thickness (LLT), lipid map uniformity (LMU), inter-blink intervals (IBI), and lipid break-up time (LBUT). Results: Average ages significantly differed (p = 0.013) between the treatment group (66.5 years) and control group (average age 51.5 years), and thus results were adjusted for age accordingly. IOP was 17.1 mmHg in the treatment group and 16.1 mmHg in the control group. When analyzing the sublayers of the TF, MALTR had a significant association with IOP-lowering therapy after adjusting for age, with a difference of −52.68 nm/s; 95% confidence interval [−96.87, −8.48]; p-value = 0.020. Additionally, IBI was significantly associated with IOP-lowering therapy after log transformation (p = 0.049), with shorter IBI in the treatment group. All other metrics (MALT, LLT, LMU, and LBUT) were statistically insignificant (p > 0.05). Conclusions: These pilot results suggest that IOP-lowering drops may accelerate thinning of the TF, specifically the muco-aqueous layer. Longitudinal studies with significantly larger samples are needed to specify the differential impact of various ocular hypotensive therapies on the human TF and the clinical implications of these findings. Full article

Carbonic anhydrases (CAs) efficiently catalyze CO₂ reversible hydration, critical for carbon capture and sequestration (CCS), but naturally low yield limits industrial use. Yarrowia lipolytica, an unconventional yeast, is an ideal heterologous expression host with robust adaptability, post-translational modification capacity, and versatile genetic tools. In this study, 10 α-, β-, and γ-class CAs were successfully expressed in Y. lipolytica, and two top-performing candidates were identified: Methanosarcina mazei γ-CA (MmaCA) and Sulfurihydrogenibium azorense α-CA (SazCA). Their production was further optimized via promoter and gene dosage adjustment, cultural condition optimization and auxiliary protein co-expression. The optimized intracellular MmaCA activity reached 960 U/mL (64.42-fold improvement), and the extracellular SazCA activity peaked at 925 U/mL (70.08-fold enhancement). CO₂ mineralization experiments confirmed both recombinant CAs significantly accelerated CaCO₃ precipitation, demonstrating a promising CCS application potential. To our knowledge, this is the first systematic investigation of CA heterologously expressed in Y. lipolytica, providing a novel strategy for the highly efficient production of CAs to enable their application in industry. Full article

The continuous increase in atmospheric CO₂ concentration exacerbates global climate change, making carbon reduction an urgent global priority. Carbonic anhydrase (CA), a highly efficient biocatalyst that converts CO₂ into bicarbonate, demonstrates significant potential for carbon capture and resource utilization. However, the stability and catalytic efficiency of native CA in industrial environments are limited, particularly its poor thermal tolerance under flue gas conditions and its sensitivity to impurities, hindering its direct large-scale application. This review systematically summarizes recent advances in modifying microbial CA through protein engineering (e.g., directed evolution, rational design) and immobilization techniques, which have markedly enhanced its thermal stability, adaptability, and reusability. Among these, the integration of machine learning with high-throughput experimentation has emerged as a transformative strategy for CA engineering. Furthermore, we outline CA-driven pathways for CO₂ conversion into high-value chemicals and bioenergy. Finally, future prospects are discussed, including interdisciplinary integration, computational modeling coupled with experimental validation, and comprehensive life-cycle and techno-economic assessments, to facilitate the scaled application of engineered microbial CA in carbon neutrality pathways. Collectively, this review highlights the critical role of engineered CA in bridging biocatalysis with industrial carbon management, offering a viable and sustainable pathway toward carbon neutrality. Full article

Carbonic anhydrase VA (CA5A) deficiency (OMIM 615751) is an ultra-rare inborn error of metabolism, presenting in newborns, infants, and young children with a pentad of encephalopathy, hyperammonemia, lactic acidosis, ketonuria, and hypoglycemia. We present two cases: a case of a healthy Bedouin infant admitted with hyperammonemic encephalopathy that required urgent hemodialysis, and her younger sibling, who presented with a milder episode. Molecular analysis confirmed the diagnosis of CA5A deficiency due to a homozygous missense variant in the CA5A gene. Both patients had a favorable outcome with continued normal development. These were the first identified cases of CA5A deficiency in the Bedouin population, emphasizing the importance of a high index of suspicion, early genetic consultation and diagnosis, and prompt treatment at the earliest possible stage of a hyperammonemic crisis. Full article

Background: Carbonic Anhydrases (CAs) represent regulators of cell adaptation to hypoxia, pH regulation, and metabolic fitness. Among cancers, multiple myeloma (MM) is a plasma cell malignancy sustained by hypoxia-driven metabolic adaptation, extracellular acidification, and redox imbalance. Tight regulation of tumor extracellular pH, mediated by Carbonic Anhydrases IX and XII, is crucial for myeloma survival, progression, and stemness, making these isoforms attractive therapeutic targets. Methods: We designed and synthesized a library of terpenoid-based hybrids by derivatizing chlorothymol and 4-isopropyl-3-methylphenol with either the natural coumarin umbelliferon or the 2,2′-dipicolylamine (DPA) scaffold. This chemical strategy aimed to selectively inhibit tumor-associated CAs IX/XII through coumarin- or DPA-mediated recognition, while terpenoid fragments were introduced to enhance lipophilicity, membrane permeability, and potential redox-modulating properties. The compounds were tested by a Stopped-Flow assay for CA inhibition, in cell-based assays for antiproliferative properties and by means of several antioxidant assays. Results: The most active compounds, connecting the coumarin core to a terpenoid tail, inhibited the targeted CAs in the nanomolar range, showing up higher selectivity over off-target isoforms (I and II). In studies performed on MM cell lines, selected derivatives reduced viability (IC₅₀ = 15.8–85.4 µM) and displayed favorable selectivity over normal cells. In silico investigations suggested that the compounds were able to interact selectively with the target enzymes. Conclusions: Collectively, these results support a dual-targeting strategy in which selective inhibition of tumor-associated CAs, combined with redox modulation, interferes with adaptive mechanisms of MM cells, providing a rational framework for the development of multifunctional agents against metabolically resilient hematological malignancies. Full article

Microalgae are among the most efficient photosynthetic organisms on Earth, and their capacity for CO₂ fixation directly links the global carbon cycle with green energy conversion, positioning them as strategic biological platforms for achieving carbon neutrality. This review provides a comprehensive and multiscale synthesis of the engineering and biological mechanisms underlying microalgal CO₂ fixation, integrating perspectives from gas–liquid mass transfer, CO₂ assimilation pathways, key enzymatic systems, metabolic regulation, and environmental control. From an engineering standpoint, we analyze the limitations governing CO₂ transfer from the gas phase to the aqueous phase and critically evaluate intensification strategies aimed at enhancing inorganic carbon availability in cultivation systems. At the biological and biochemical levels, we dissect carbon concentrating mechanisms (CCMs), including C₄-like pathways, and elucidate the structural organization, regulatory properties, and functional coordination of Rubisco and carbonic anhydrase systems. Particular emphasis is placed on the coupling between enzyme-level regulation and metabolic flux redistribution, supported by insights from metabolic flux analysis and systems-level modeling, to establish theoretical and engineering foundations for improving carboxylation efficiency. Finally, we propose an integrated roadmap for the future development of microalgal CO₂ fixation technologies, highlighting the convergence of synthetic biology, artificial intelligence, and systems engineering to achieve end-to-end optimization from molecular mechanisms to reactor-scale performance, while enabling the valorization of waste gas streams and circular carbon utilization. This review aims to provide a coherent theoretical framework and forward looking perspective for the development of efficient, intelligent, and sustainable microalgal CO₂ fixation systems. Full article