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Effects of sodium alginate (SA) on the non-covalent interaction between soybean protein isolate (SPI) and quercetin (Que) were investigated by multispectral technology, molecular docking and dynamics simulation technology. Structural alterations of the binary complexes were observed after SA addition, characterized by a red shift of maximum fluorescence emission wavelength. The introduction of 0.1% (w/v) SA led to a reduction of 12.3% in the α-helix and ß-sheet structures, accompanied by 12.6% increase in the ß-turn and random coil conformations. The binding of SA to SPI provided electrostatic interactions and facilitated the subsequent binding of SPI to Que. Molecular docking confirmed that hydrophobic interactions and electrostatic interactions were also the main driving force. Molecular dynamics simulation emphasized that the ternary complexes with SA exhibited greater stability compared to the binary ones. The foaming and emulsifying properties of SPI-Que complexes were enhanced by 33.76% and 68.28%, respectively, due to the addition of SA.

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A new series of chiral 4,5-dihydro-1H-[1,2,4]-triazoline molecules, featuring a ß-ᴅ-glucopyranoside appendage, were synthesized via a 1,3-dipolar cycloaddition reaction between various hydrazonyl chlorides and carbohydrate Schiff bases. The isolated enantiopure triazolines (8a-j) were identified through high-resolution mass spectrometry (HRMS) and vibrational spectroscopy. Subsequently, their solution structures were elucidated through NMR spectroscopic techniques. Single-crystal X-ray analysis of derivative 8b provided definitive evidence for the 3-D structure of this compound and revealed important intermolecular forces in the crystal lattice. Moreover, it confirmed the (S)-configuration at the newly generated stereo-center. Selected target compounds were investigated for anti-tumor activity in 60 cancer cell lines, with derivative 8c showing the highest potency, particularly against leukemia. Additionally, substituent-dependent anti-fungal and anti-bacterial behavior was observed.

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The most common skin diseases include eczema, psoriasis, acne, and fungal infections. There is often no effective cure for them. Increasing antimicrobial drug resistance prompts us to search for new, safe, and effective therapeutics. Among such interesting candidates are peptides derived from milk fermented with specific lactic acid bacteria or with kombucha cultures, which are a potential treasure trove of bioactive peptides. Four of them are discussed in this article. Their interactions with zinc and copper ions, which are known to improve the well-being of the skin, were characterized by potentiometry, MS, ITC, and spectroscopic methods, and their cytostatic potential was analyzed. The results suggest that they are safe for human cells and can be used alone or in complexes with copper for further testing as potential therapeutics for skin diseases.

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The linear undecapeptide KKLFKKILKYL-NH2 (BP100) highlights for its antibacterial activity against Gram-negative bacteria and its low toxicity. These excellent biological properties prompted the investigation of its mechanism of action, which were undertaken using spectroscopic techniques, biophysical analysis, microscopy, and molecular dynamic simulations. Studies were conducted in different membrane environments, such as anionic, zwitterionic, and mixed membranes, as well as in vesicles (LUVs and GUVs) and bacteria. The findings suggest that BP100 exhibits a preference for anionic membranes, and its mechanism of action involves charge neutralization and membrane permeabilization. In these membranes, BP100 transitions from an unstructured state in water to an α-helix with the axis parallel to the surface. MD simulations suggest that after electrostatic interaction with the membrane, BP100 flips, facilitating the insertion of its hydrophobic face into the membrane bilayer. Thus, BP100 adopts an almost vertical transmembrane orientation with lysine side chains snorkelling on both sides of the membrane. As a result of the rotation, BP100 induces membrane thinning and slow lipid diffusion and promotes water penetration, particularly in anionic lipid membranes. These investigations pointed towards a carpet-like mechanism and are aligned with the biological activity profile described for BP100. This review covers all the studies carried out on the mechanism of action of BP100 published between 2009 and 2023.

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BACKGROUND: Gambogic acid (GA) is a natural product from the resin of the Garcinia species, which showed significant activity in the induction of apoptosis. .t can be one promising lead compound for the design and synthesis of new anticancer drugs. OBJECTIVE: The objective of the current study is to design novel nitrogen-contained GA derivatives with better anti-cancer activities and study the effect of the introduction of different nitrogen-contained groups on the activity of GA. METHODS: The designed 15 derivatives were synthesized via esterification or amidation of 30-carboxylate. The synthetic compounds were characterized via different spectroscopic techniques, including X-ray single crystal diffraction, MS and NMR. The cytotoxic activity of the designed derivatives was evaluated in vitro against A549, HepG-2, and MCF-7 cell lines using methyl thiazolyl tetrazolium (MTT) test. RESULTS: 15 nitrogen-contained GA derivatives were successfully synthesized and established. Based on the IC50 values, compounds 9, 10, 11 and 13 showed stronger inhibitory effects on A549, HepG-2, MCF-7 cell lines than GA, while 9 is the most active compound with IC50 value of 0.64-1.49 µM. Most derivatives of GA with esterification of C-30 including cyano-benzene ring were generally weaker than those of pyrimidinyl-substituted derivatives. In addition, length of alkyl linkers between C-30 of GA and nitrogen-contained group produced different effects on A549, HepG-2 and MCF-7 cell lines. CONCLUSION: The structure-activity relationship results show that aromatic substituent and linker length play important roles to improve the anticancer activities, while compound 9 with pyrimidine substituent and C-C-C linkers is the most active derivative against tested cell lines, and is a promising anti-cancer agent for further development.

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Under physiological conditions, spectroscopic techniques as well as molecular docking simulation have been used to investigate the binding interaction mechanism between Cu(II) complex containing Pyridine-2,6-dicarboxylic acid (PDCA) and Diethanolamine (DEA) ligands, [Cu(DEA)(PDCA)] and human serum albumin (HSA). UV spectral changes of protein in the presence of the Cu(II) complex suggested the formation of a Protein-Cu(II) complex conjugate with specific new structure. The Cu(II) complex quenches the intrinsic fluorescence of the HSA via a static mechanism in which van der Waals interactions along with hydrogen bonds are fundamental binding forces. Displacement experiments performed by warfarin and ibuprofen site probes predict that the Cu(II) complex is located in subdomain IIA, Sudlow site 1 of HSA. Molecular docking results showed close resemblance with experimental data.Communicated by Ramaswamy H. Sarma.

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In this work, atomic cobalt (Co) incorporation into the Pd2Ge intermetallic lattice facilitates operando generation of a thin layer of CoO over Co-substituted Pd2Ge, with Co in the CoO surface layer functioning as single metal sites. Hence the catalyst has been titled Co1-CoO-Pd2Ge. High-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy confirm the existence of CoO, with some of the Co bonded to Ge by substitution of Pd sites in the Pd2Ge lattice. The role of the CoO layer in the oxygen evolution reaction (OER) has been verified by its selective removal using argon sputtering and conducting the OER on the etched catalyst. In situ X-ray absorption near-edge structure and extended X-ray absorption fine structure spectroscopy demonstrate that CoO gets transformed to CoOOH (Co3+) in operando condition with faster charge transfer through Pd atoms in the core Pd2Ge lattice. In situ Raman spectroscopy depicts the emergence of a CoOOH phase on applying potential and shows that the phase is stable with increasing potential and time without getting converted to CoO2. Density functional theory calculations indicate that the Pd2Ge lattice induces distortion in the CoO phase and generates unpaired spins in a nonmagnetic CoOOH system resulting in an increase in the OER activity and durability. The existence of spin density even after electrocatalysis is verified from electron paramagnetic resonance spectroscopy. We have thus successfully synthesized intermetallic supported CoO during synthesis and rigorously verified the role played by an intermetallic Pd2Ge core in enhancing charge transfer, generating spin density, improving electrochemical durability, and imparting mechanical stability to a thin CoOOH overlayer. Differential electrochemical mass spectrometry has been explored to visualize the instantaneous generation of oxygen gas during the onset of the reaction.

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Assessment of regional lymph node status in breast cancer is of important staging and prognostic value. Even though formal histological examination is the currently accepted standard of care, optical imaging techniques have shown promising results in disease diagnosis. In the present article, we review six spectroscopic techniques and focus on their use as alternative tools for breast cancer lymph node assessment. Elastic scattering spectroscopy (ESS) seems to offer a simple, cost-effective, and reproducible method for intraoperative diagnosis of breast cancer lymph node metastasis. Optical coherence tomography (OCT) provides high-resolution tissue scanning, along with a short data acquisition time. However, it is relatively costly and experimentally complex. Raman spectroscopy proves to be a highly accurate method for the identification of malignant axillary lymph nodes, and it has been further validated in the setting of head and neck cancers. Still, it remains time-consuming. Near-infrared fluorescence imaging (NIRF) and diffuse reflectance spectroscopy (DFS) are related to significant advantages, such as deep tissue penetration and efficiency. Fourier-transform infrared spectroscopy (FTIR) is a promising method but has significant drawbacks. Nonetheless, only anecdotal reports exist on their clinical use for cancerous lymph node detection. Our results indicate that optical imaging methods can create informative and rapid tools to effectively guide surgical decision-making.

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Rice is a staple food for two-thirds of the world's population and is grown in over a hundred countries around the world. Due to its large scale, it is vulnerable to adulteration. In addition, the quality attribute of rice is an important factor affecting the circulation and price, which is also paid more and more attention. The combination of spectroscopy and chemometrics enables rapid detection of authenticity and quality attributes in rice. This article described the application of seven spectroscopic techniques combined with chemometrics to the rice industry. For a long time, near-infrared spectroscopy and linear chemometric methods (e.g., PLSR and PLS-DA) have been widely used in the rice industry. Although some studies have achieved good accuracy, with models in many studies having greater than 90% accuracy. However, higher accuracy and stability were more likely to be obtained using multiple spectroscopic techniques, nonlinear chemometric methods, and key wavelength selection algorithms. Future research should develop larger rice databases to include more rice varieties and larger amounts of rice depending on the type of rice, and then combine various spectroscopic techniques, nonlinear chemometric methods, and key wavelength selection algorithms. This article provided a reference for a more efficient and accurate determination of rice quality and authenticity.

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This article aims to review research updates and progress on the nutritional significance of the amides I and II, the alpha-helix and beta-sheet ratios, the microbial protein synthesis, and the steam pressure toasting condition in food and feed with globar and synchrotron molecular microspectroscopic techniques plus chemometrics (both univariate and multivariate techniques). The review focused on (I) impact of the amides I and II, and the alpha-helix and beta-sheet-structure ratios in food and feeds; (II) Current research progress and update in synchrotron technique and application in feed and food molecular structure studies that are associated with nutrition delivery; (III) Impact of thermal processing- steam pressure toasting condition on feed and food; (IV). Impact of the microbial protein synthesis and methodology on feed and food; and (V). Impact on performance and production of ruminants with Faba beans.

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The interaction mechanism of hemoglobin (Hb) with bisphenol A (BPA) in diabetic patients and the difference with healthy people have been studied using spectroscopic and molecular docking techniques at several glucose (Glc) concentration, with bovine hemoglobin (BHb) instead of Hb. It is found that Glc can interact with BHb-BPA and affect its molecular structure, resulting in an altered microenvironment for tyrosine (Tyr) and tryptophan (Trp) in BHb-BPA. It is also found that Glc can bind to BHb alone, and its effect on the molecular structure of BHb is weaker than that on the structure of BHb in BHb-BPA complex. The results of circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) indicate that Glc causes an increase in the content of the α-helix and a decrease in that of the ß-sheet of BHb-BPA by 1.5-1.9% and 3.1%, respectively. The results of molecular docking show that Glc binds to BHb-BPA through hydrogen and hydrophobic bonds, and the position of binding differs from that of Glc binding to BHb alone, which may be attributed to the fact that BPA affects the protein molecular structure of BHb and has an effect on the binding of BHb to Glc. This study provides some theoretical basis for the mechanism of BPA toxicity in vivo for people with different blood glucose levels.

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Bisphenol A (BPA) is an endocrine-disrupting compound, and the binding mechanism of BPA with carrier proteins has drawn widespread attention. Halogen substitutions can significantly impact the properties of BPA, resulting in various effects for human health. Here, we selected tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA) to investigate the interaction between different halogen-substituted BPAs and human serum albumin (HSA). TBBPA/TCBPA spontaneously occupied site I and formed stable binary complexes with HSA. Compared to TCBPA, TBBPA has higher binding affinity to HSA. The effect of different halogen substituents on the negatively charged surface area of BPA was an important reason for the higher binding affinity of TBBPA to HSA compared to TCBPA. Hydrogen bonds and van der Waals forces were crucial in the TCBPA-HSA complex, while the main driving factor for the formation of the TBBPA-HSA complex was hydrophobic interactions. Moreover, the presence of TBBPA/TCBPA changed the secondary structure of HSA. Amino acid residues such as Lys199, Lys195, Phe211, Arg218, His242, Leu481, and Trp214 were found to play crucial roles in the binding process between BPA compounds and HSA. Furthermore, the presence of halogen substituents facilitated the binding of BPA compounds with HSA.

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The main aim of this study is to find relevant analytic fingerprints for plants' structural characterization using spectroscopic techniques and thermogravimetric analyses (TGAs) as alternative methods, particularized on cabbage treated with selenium-baker's yeast vinasse formulation (Se-VF) included in a foliar fertilizer formula. The hypothesis investigated is that Se-VF will induce significant structural changes compared with the control, analytically confirming the biofortification of selenium-enriched cabbage as a nutritive vegetable, and particularly the plant biostimulant effects of the applied Se-VF formulation on cabbage grown in the field. The TGA evidenced a structural transformation of the molecular building blocks in the treated cabbage leaves. The ash residues increased after treatment, suggesting increased mineral accumulation in leaves. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) evidenced a pectin-Iα-cellulose structure of cabbage that correlated with each other in terms of leaf crystallinity. FTIR analysis suggested the accumulation of unesterified pectin and possibly (seleno) glucosinolates and an increased network of hydrogen bonds. The treatment with Se-VF formulation induced a significant increase in the soluble fibers of the inner leaves, accompanied by a decrease in the insoluble fibers. The ratio of soluble/insoluble fibers correlated with the crystallinity determined by XRD and with the FTIR data. The employed analytic techniques can find practical applications as fast methods in studies of the effects of new agrotechnical practices, while in our particular case study, they revealed effects specific to plant biostimulants of the Se-VF formulation treatment: enhanced mineral utilization and improved quality traits.

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In environmental systems, the soil is a principal route of contamination by various potentially toxic species. Roxarsone (RX) is an arsenic (V) organic compound used to treat parasitic diseases and as an additive for animal fattening. When the animal excretes RX, the residues may lead to environmental contamination. Due to their physicochemical properties, the soil's humic substances (HS) are important in species distribution in the environment and are involved in various specific interaction/adsorption processes. Since RX, an arsenic (V) compound, is considered an emerging contaminant, its interaction with HS was evaluated in simulated environmental conditions. The HS-RX interaction was analyzed by monitoring intrinsic HS fluorescence intensity variations caused by complexation with RX, forming non-fluorescent supramolecular complexes that yielded a binding constant Kb (on the order of 103). The HS-RX interaction occurred through static quenching due to complex formation in the ground state, which was confirmed by spectrophotometry. The process was spontaneous (ΔG < 0), and the predominant interaction forces were van der Waals and hydrogen bonding (ΔH < 0 and ΔS < 0), with an electrostatic component evidenced by the influence of ionic strength in the interaction process. Structural changes in the HS were verified by synchronized and 3D fluorescence, with higher variation in the region referring to the protein-like fraction. In addition, metal ions (except ions Cu(II)) favored HS-RX interaction. When interacting with HS, the RX epitope was suggested by 1H NMR, which indicated that the entire molecule interacts with the superstructure. An enzyme inhibition assay verified the ability to reduce the alkaline phosphatase activity of free and complexed RX (RX-HS). Finally, this work revealed the main parameters associated with HS and RX interaction in simulated environmental conditions, thus, providing data that may help our understanding of the dynamics of organic arsenic-influenced soils.

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As a new generation of 'green solvents' deep eutectic solvents (DESs) represents a promising alternative to the conventional solvents. Their environmental-benign nature and designer properties promote their utility in biocatalysis. Enzymes are marginally stable when exposed to physical/chemical disturbances. One such enzyme is cellulase which is a propitious catalyst for the depolymerization of cellulose under mild conditions. Therefore, their stability is a prerequisite condition to match demands of biorefineries. To address this issue of low stability, activity and thermal denaturation of cellulase, there is a need to find a sustainable and suitable co-solvent that is biocompatible with enzymes ultimately to facilitate their application in bio-industries. In this regard, we synthesized three choline-based DESs, choline chloride (ChCl)-glycerol, ChCl-ethylene glycol and ChCl-lactic acid and employed them to analyze their suitability for cellulase. The present study systematically evaluates the influence of the mentioned DESs on stability, activity and thermal stability of cellulase with the help of various spectroscopic techniques. The spectroscopic analysis revealed that the structural stability and activity of the enzyme were improved in presence of ChCl-glycerol and ChCl-ethylene glycol. The thermal stability was also very well maintained in both the DESs. Interestingly, the relative activity of cellulase was >80 % even after incubation at 50 °C after 48 h for both the DESs. This activity preservation behaviour was more pronounced for ChCl-ethylene glycol than ChCl-glycerol. Moreover, temperature variations studies also reveal promising results by maintain conformational intactness. On the other side, ChCl-lactic acid showed a deleterious effect on the enzyme both structurally as well as thermally. The dynamic light scattering (DLS) analysis provides more specific information about the negative influence of ChCl-lactic acid towards cellulase native structure. This DES induces unavoidable alterations in the enzyme structure which leads to the unfolding of enzyme, ultimately, destabilizing it. Overall, our results present a physical insight into how the enzyme stability and activity depend on the nature of DES. Also, the findings will help to facilitate the development and application of DESs as biocatalytic process.

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Omega-3 fatty acids v(ω-3 FAs) such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) and omega-6 fatty acids (ω-6 FAs) such as linoleic acid and arachidonic acid are important fatty acids responsible for positive effects on human health. The main sources of ω-3 FAs and ω-6 FAs are marine-based products, especially fish oils. Some food, supplements, and pharmaceutical products would include fish oils as a source of ω-3 FAs and ω-6 FAs; therefore, the quality assurance of these products is highly required. Some analytical methods mainly based on spectroscopic and chromatographic techniques have been reported. Molecular spectroscopy such as Infrared and Raman parallel to chemometrics has been successfully applied for quantitative analysis of individual and total ω-3 FAs and ω-6 FAs. This spectroscopic technique is typically applied as the alternative method to official methods applying chromatographic methods. Due to the capability to provide the separation of ω-3 FAs and ω-6 FAs from other components in the products, gas and liquid chromatography along with sophisticated detectors such as mass spectrometers are ideal analytical methods offering sensitive and specific results that are suitable for routine quality control.

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In this study, a method of mid-level data fusion with the fingerprint region was proposed, which was combined with the characteristic wavelengths that contain fingerprint information in NIR and FT-MIR spectra to detect the DON level in FHB wheat during wheat processing. NIR and FT-MIR raw spectroscopy data on normal wheat and FHB wheat were obtained in the experiment. MSC was used for pretreatment, and characteristic wavelengths were extracted by CARS, MGS and XLW. The variables that can effectively reflect fingerprint information were retained to build the mid-level data fusion matrix. LS-SVM and PLS-DA were applied to investigate the performance of the single spectroscopic model, mid-level data fusion model and mid-level data fusion with fingerprint information model, respectively. The experimental results show that mid-level data fusion with a fingerprint information strategy based on fused NIR and FT-MIR spectra represents an effective method for the classification of DON levels in FHB wheat samples.

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Introduction: Fingolimod is a drug that is used to treat multiple sclerosis (MS). It has pH-dependent solubility and low solubility when buffering agents are present. Multi-spectroscopic and molecular modeling methods were used to investigate the molecular mechanism of Fingolimod interaction with human serum albumin (HSA), and the resulting data were fitted to the appropriate models to investigate the molecular mechanism of interaction, binding constant, and thermodynamic properties. Methods: The interaction of Fingolimod with HSA was investigated in a NaCl aqueous solution (0.1 mM). The working solutions had a pH of 6.5. Data was collected using UV-vis, fluorescence quenching titrations, FTIR, and molecular modeling methods. Results: According to the results of the fluorescence quenching titrations, the quenching mechanism is static. The apparent binding constant value (KA = 4.26×103) showed that Fingolimod is a moderate HSA binder. The reduction of the KA at higher temperatures could be a result of protein unfolding. Hydrogen bonding and van der Waals interactions are the main contributors to Fingolimod-HSA complex formation. FTIR and CD characterizations suggested a slight decrease in the α-helix and ß-sheets of the secondary structure of HSA due to Fingolimod binding. Fingolimod binds to the binding site II, while a smaller tendency to the binding site I was observed as well. The results of the site marker competitive experiment and the thermodynamic studies agreed with the results of the molecular docking. Conclusion: The pharmacokinetic properties of fingolimod can be influenced by its HSA binding. In addition, considering its mild interaction, site II binding drugs are likely to compete. The methodology described here may be used to investigate the molecular mechanism of HSA interaction with lipid-like drugs with low aqueous solubility or pH-dependent solubility.

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This work presents the study of the moisture ratio and carotenoid compounds in dried mamey (Pouteria sapota) using non-invasive spectroscopic techniques. The drying behavior of mamey at 64 °C by a homemade solar dryer is analyzed by fitting the experimental data to four different mathematical drying models. In addition, this result is compared with other drying techniques, namely by heat chamber with natural convection at temperatures of 50 °C and 60 °C. The results show that the Lewis model is the one that best fits the experimental moisture ratio curve of mamey. On the other hand, Near-Infrared and Terahertz spectroscopic techniques are used to estimate the moisture ratio, since water absorption is most sensitive at these frequencies. Fourier Transform Infrared-attenuated total reflectance and Raman spectroscopy are performed to detect the carotenoid compounds in dried mamey. This compound has important applications in the food industry and health benefits. To our knowledge, there are few studies on the dehydration of Pouteria sapota as well as its characterization using spectroscopic techniques for the detection of moisture ratio and carotenoid content; therefore, this study can be useful in agriculture and food sectors when detailed information about the cited parameters is needed.

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A new zinc(II) complex formulated as [Zn(pipr-ac)2], where pipr-ac stands for piperidineacetate, was synthesized and structurally identified with the help of experimental and DFT methods. Frontier molecular orbital (FMO) analysis demonstrated that the new complex has higher biological activity compared to the free ligand. Molecular electrostatic potential (MEP) showed the nitrogen atoms and oxygen of carbonyl groups are the active sites of Zn(II) compound. Also, natural bond orbital (NBO) analysis confirmed the charge transfer from the ligating atoms to the metal ion and formation of four coordinated Zn(II) complex. MTT assay illustrated a noticeable cytotoxic activity of the new zinc(II) complex compared to cisplatin on K562 cell line. The CT-DNA and serum albumin (SA) binding of the Zn(II) complex were explored individually. In this regard, UV-Vis spectroscopy and florescence titration revealed the occurrences of fluorescence quenching of CT-DNA/SA by metal compound via static mechanism and creation of hydrogen bonds and van der Waals interactions between them. The binding was further confirmed by viscosity measurement and gel electrophoresis assay for CT-DNA and circular dichroism spectroscopy for SA. Moreover, molecular docking simulation demonstrated that the new compound binds mainly through hydrogen bonds to the groove of DNA and hydrogen bonds and van der Waals interactions to site I of SA.

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