The journal retracts the article "Synthetic Makaluvamine Analogs Decrease c-Kit Expression and Are Cytotoxic to Neuroendocrine Tumor Cells" [...].

Missing acknowledgement [...].

In the original publication [...].

In the original publication [...].

Indocyanine green (ICG) is a clinically approved near-infrared fluorescent dye used in medical imaging and diagnostics but has limitations owing to its poor photostability in aqueous environments. This paper has explored the role of human serum albumin (HSA) and cholesterol in protecting ICG photostability. Pure ICG, an HSA-ICG complex, and an ICG-cholesterol colloidal assembly solution were stirred in the dark (control) and under continuous broadband irradiation (400-1600 nm, approximately 1.4 W), and absorption spectra (550-950 nm) were taken every 1 min, over 15 min. All the formulations were stable in the dark, with minimal total variance in absorbance. Pure ICG significantly photodegraded under irradiation (55 ± 2.75-65 ± 3.25% loss of maximum absorbance). The introduction of HSA and cholesterol limited the photodegradation, resulting in 15 ± 0.75-30 ± 1.5% and 25 ± 1.25% losses in maximum absorbance, respectively, upon irradiation. The modulators produced a significant increment in initial NIR absorbance (p < 0.001) and retained significantly high stability during irradiation (p < 0.01). Moreover, both modulators reduced photooxidative damage, as shown by the lower level of singlet oxygen ([1]O2) generation in the presence of HSA-ICG (35 ± 1.75%) and ICG-cholesterol (19 ± 0.95%) compared to pure ICG (57 ± 2.85% after 15 min). These results reveal that cholesterol is the best stabilizer of ICG photostability. By safely dissipating excitation energy via non-radiative decay, cholesterol demonstrates strong potential for enhancing ICG performance in photothermal therapy (PTT), whereas HSA remains the optimal modulator for near-infrared fluorescence imaging and photodynamic therapy.

The extracts of the Alcea rosea L. flowers are known to show various kinds of biomedical activities and are widely used as food and cosmetic ingredients. Unfortunately, no comprehensive analysis aimed at the identification of the most abundant flavonoid glycosides present in the extract of Alcea rosea L. has been made as of yet. In this paper we present the LC-MS identification of the most abundant flavonoid glycosides in the methanol and 75% ethanol extracts of Alcea rosea L. obtained from two manufacturers. The identification has been based on the detection of the respective parent and product ions as well as their relative abundances. The differences between identified isomeric and isobaric compounds have also been discussed. In all extracts a number of 3-O-anthocyanidin glycosides (anthocyanins) and 3-O-flavonol glycosides have been identified. Among the anthocyanins, the most abundant were malvidin glycosides, e.g., malvidin 3-O-(6″-[E]-p-coumaroyl)glucoside; among the flavonol glycosides, the most abundant were kaempferol glycosides, e.g., tiliroside.

Aloe vera is a renowned phytotherapeutic plant characterized by a highly dynamic chemical profile and endowed with a broad spectrum of biological activities. Industrial processing of A. vera focuses almost exclusively on the inner parenchyma (AG), discarding the epidermal tissue (AS) as waste. This study addresses the valorization of this byproduct through a comparative evaluation of the phytochemical and biological profiles of hydroalcoholic extracts obtained from both AG and AS. In vitro studies revealed that AS extract exhibited better antioxidant and anti-inflammatory activities than AG and good wound-healing properties, driven by its rich content of anthraquinones and polyphenols. Both extracts were successfully incorporated into a mucoadhesive xanthan gum matrix to engineer an advanced emulgel with suitable viscosity for prolonged mucosal adherence in Gastro-Esophageal Reflux Disease (GERD) management. Rheological profiling against commercial references confirmed that the xanthan-AS formulation provided comparable rheological properties, fully preserving the extract's anti-inflammatory activity. Ultimately, this study highlights the pharmaceutical potential of A. vera skin, offering a sustainable strategy to transform an industrial byproduct into an innovative formulation for potential GERD management.

An efficient and stereoselective method for the synthesis of chiral biheterocyclic N-Boc-protected pyrrolidine derivatives bearing indole, pyrazole, and indazole moieties is presented. In this approach, nucleophilic substitution of heterocyclic carboxylates with enantiomerically pure N-Boc-3-methanesulfonyloxypyrrolidines is used to afford N-(pyrrolidin-3-yl) derivatives in high yields with an inverted configuration. The methodology accommodates a range of substrates, enabling structural diversity. Reactions with pyrazole- and indazolecarboxylates generate regioisomeric products. Representative peptide-coupling reactions further demonstrated the synthetic utility of the synthesized chiral biheterocyclic pyrrolidine derivatives containing protected amino and carboxyl functionalities as building blocks for peptide synthesis. Halogenated indole and pyrazole derivatives underwent further functionalization via palladium-catalyzed cross-coupling to introduce aryl, heteroaryl, and alkynyl substituents. All of the N-Boc-substituted biheterocycle-pyrrolidine carboxylates displayed NMR spectra with two sets of signals, notable signal broadening, or both. These effects are due to the dynamic equilibrium between two conformers in a deuterated solvent and were studied in depth. The structures and stereochemistry of the synthesized compounds were confirmed by means of chiral HPLC, single-crystal X-ray diffraction, and advanced NMR analyses. This synthetic strategy provides access to chiral heterocyclic amino acid-like building blocks for peptide synthesis and medicinal chemistry.

Argemone ochroleuca and Argemone mexicana are widespread weed species known for being rich in various secondary metabolites. However, a comprehensive understanding of their chemical diversity remains limited. Insufficient information exists on metabolite variation between plant parts and the influence of solvent polarity on metabolite recovery. Therefore, this study aimed to characterize the metabolomic profiles of the shoots and root extracts of both species using solvents of varying polarity to evaluate plant part-specific metabolite distribution and solvent effects on metabolome coverage. Untargeted ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS)-based metabolomics and molecular networking were employed for metabolite analysis. Principal component analysis (PCA) did not reveal clear clustering of A. ochroleuca and A. mexicana, suggesting similarities in their metabolomic profiles. A total of 15 and 13 metabolite classes, yielding 59 and 54 metabolites, were identified in A. ochroleuca and A. mexicana, respectively, including flavonoids, terpenoids, phenolic compounds, fatty acids, and monoterpenoids. Argemone ochroleuca exhibited higher metabolite abundance, particularly in methanol and acetone extracts, and with shoots showing higher abundance than roots, with flavonoids being the dominant class. The findings show that LC-MS metabolomics, molecular networking, and careful solvent selection are effective for identifying key metabolites with potential applications in crop protection.

Titanium dioxide (TiO2) photocatalysis is a promising sustainable solution for water decontamination; however, the industrial application of TiO2 is hindered by its wide band gap and high handling and recovery costs. This work proposes to overcome these issues by developing a composite coating of nanopowder TiO2 and reduced graphene oxide (rGO) applied onto commercial polyurethane (PU) foams by means of a simple, low-energy dip-coating process designed to enhance pollutant adsorption and photocatalytic activity. The rGO-TiO2 coating was optimized by exploring different surface pre-treatments of the PU foams, the deposition of rGO-TiO2 multilayers, and the variation in the rGO-TiO2 mass ratio (1:3, 1:4, and 1:5). The prepared materials were characterized by optical microscopy, SEM-EDX, DSC, and thermogravimetry, while the stability of the coating was preliminarily evaluated through ultrasonic tests. The water decontamination capability of the coated foams was investigated by adsorption and UV-Vis photodegradation tests using a 3 mg/L aqueous solution of Rhodamine B (RhB) as a model contaminant. The results demonstrated that the rGO-TiO2 1:3-coated samples achieved complete RhB photodegradation within 90 min, with a pseudo-first-order kinetic constant of 0.0446 1/min. Moreover, pre-treating the foam with a 3 M NaOH solution improved coating adhesion onto the PU substrate while maintaining comparable decontamination efficiency.

A previous investigation on limonene (LM), perillyl alcohol (POH), and carveol (CV), focused on the structure-activity relationship and hydroxyl group, documented that the presence of the hydroxyl group influences the pharmacodynamic potency of these agents, inhibiting smooth muscle contraction with the order of potency: POH > CV > LM. That investigation also suggested a mechanism of action, which importantly included activity on the voltage-dependent calcium channel. Here, we investigated whether this structure-activity relationship also applies to nerve excitability (an activity greatly dependent on sodium channels) using compound action potential (CAP) recordings from mouse sciatic nerves and in silico simulations. POH, CV, and LM inhibited both the positive amplitudes and conduction velocities of the two CAP components in a concentration-dependent manner, with IC50 values of 0.8, 1.0, and 4.3 mM (1st component) and 0.6, 0.6, and 3.0 mM (2nd component) for amplitude, and 2.4, 2.4, and 7.1 mM (1st component) and 1.0, 2.6, and 4.3 mM (2nd component) for conduction velocity. The order of pharmacodynamic potency, thus, was POH = CV > LM. In silico simulation demonstrated that POH and CV penetrate the Nav 1.6 and accommodate in the channel at the interface between the selectivity filter and the central cavity, a position very favorable to block the channel pore. In contrast, LM exhibited a markedly different docking profile, suggesting that LM binding is less likely to directly obstruct sodium permeation. In conclusion, the three substances investigated inhibited nerve excitability, but those with a hydroxyl group demonstrated greater pharmacodynamic potency.

Hemp hurds (HHs), an underutilised lignocellulosic biomass (LB) from agricultural waste, offer potential for bioconversion into high-value bioproducts within a circular bioeconomy. Building on prior work involving magnetic nanoparticle-immobilised cellulase hydrolysis of pretreated HH, this study computationally designed candidate phaCAB expression constructs for cellulolytic hosts toward future polyhdroxybutyrate (PHB) production. The objective was to evaluate, in silico, the feasibility of introducing the phaC1, phaA and phaB1 genes from Cupriavidus necator H16 (C. necator) (assembly GCA_000009285.2; loci H16_A1437-H16_A1439) into the cellulolytic hosts Clostridium thermocellum DSM 1313 (C. thermocellum) and Trichoderma reesei RUT C-30 (T. reesei). Coding sequences were retrieved and translated individually and host-specific expression compatibility was assessed via codon adaptation index, effective number of codons, GC content and rare-codon frequency/clustering. Host-specific architectures were designed: three independent tef1-promoter cassettes with fungal Kozak contexts and cbh1 terminators for T. reesei (TrePHB3 integration construct), and a single groEL-promoter operon with graded ribosome-binding sites for the pIKM1-based C. thermocellum construct (pCtPHB1); Escherichia coli BL21 (DE3) (E. coli)/pET-24a(+) served only as an intermediate assembly platform. Clustal Omega alignment, virtual plasmid assembly and simulated restriction digestion (SnapGene) confirmed preservation of the open reading frames and expected fragment sizes. ProtParam analysis indicated instability indices below 40 and negative GRAVY values for PhaC, PhaA and PhaB, indicating overall hydrophilic character. This computational framework links HH valorisation, cellulolytic Consolidated Bioprocessing (CBP) hosts and PHB pathway design within a conceptual biorefinery, supporting future integrated biomass-valorisation platforms; it is computational only and does not demonstrate transformation, expression, PHB accumulation or biomass conversion, which require experimental validation.

The enantiomeric composition of products obtained from isomerization of n-humulone 1a to trans- and cis-n-isohumulones 2a and 3a, respectively, was determined by chiral HPLC analysis of the isolated trans and cis isomers. Enantiomers of humulone 1 were readily resolved on a Whelk-O1 chiral stationary phase (CSP), whereas the isomeric isohumulones 2 and 3 were separated on a carbohydrate-based IC-3 CSP. Magnesium-catalyzed isomerization of n-humulone under basic conditions gave mixtures of trans- and cis-n-isohumulones exhibiting an increasing preference for the cis isomer at lower temperatures. At either 10 °C in CH2Cl2/H2O or reflux in methanol-water, the trans-(-) (4S,5S)-2a isomer was obtained in greater than 95% ee, while diastereomeric cis-3a exhibited 88% ee of the (+)-(4S,5R) enantiomer. Precision continuous flow photochemical isomerization using 395 nm LEDs provided trans-(-)-2a in greater than 95% ee in an isolated yield of 93%. However, photochemical isomerization with 365 nm LEDs gave a mixture of isomers consisting of 46% ee for the trans-(-)-2a and greater than 95% ee for the cis-(-)-(4R,5S)-3a enantiomer. The photochemically obtained (-)-3a isomer has the opposite absolute configuration compared to thermal isomerization. An oxadi-π-methane rearrangement is proposed to account for the formation of isohumulone isomers under photochemical conditions.

Neglected arboviruses dengue (DENV), Zika (ZIKV), yellow fever (YFV), Japanese encephalitis (JEV), and chikungunya collectively affect hundreds of millions of people annually, yet no specific antiviral drug has been approved for any of them. Alkaloids, nitrogen-containing specialized metabolites produced by diverse plant families, have emerged as a promising source of broad-spectrum antiviral scaffolds. This review compiles and critically analyzes over 100 alkaloid-virus pairs across several RNA virus families, providing a comparative mechanistic analysis. Lycorine, narciclasine, emetine, and berbamine, among others, exhibit potent activity against phylogenetically distant viruses, with the most potent activities reported against flaviviruses (narciclasine: EC50 0.02 µM against DENV, ZIKV, YFV, and JEV; pancratistatine: 0.0063 µM against ZIKV). Structure-activity analysis of multiple alkaloid classes identifies key pharmacophoric features, including the phenanthridine nucleus (lycorine derivatives) and the bis-benzylisoquinoline scaffold (tetrandrine, berbamine), as determinants of antiviral potency, selectivity, and broad-spectrum activity. Genetic resistance data in West Nile virus challenge the widely accepted model of lycorine as a direct nucleoside inhibitor, instead pointing toward the involvement of the membrane-associated NS4A-2K-NS4B replication complex, though direct validation remains limited for other flaviviruses. Converging structural, biochemical, and transcriptomic evidence suggests that ribosome-mediated translational stress may represent an additional host-directed antiviral mechanism for isoquinoline-type alkaloids, though the causal chain from ribosome binding to activation of the integrated stress response and to antiviral effect has not been established. The present analysis highlights that in vivo validation remains limited to a few alkaloid-virus pairs. Unbiased target deconvolution and formal testing of the ribosome/integrated stress response hypothesis stand out as essential research priorities.