Synchrotron Radiation-based Fourier Transform Infrared Research Articles

Human Primary Lens Epithelial Cultures on Basal Laminas Studied by Synchrotron-Based FTIR Microspectroscopy for Understanding Posterior Capsular Opacification.

Human primary lens epithelial cultures serve as an in vitro model for posterior capsular opacification (PCO) formation. PCO occurs when residual lens epithelial cells (LECs) migrate and proliferate after cataract surgery, differentiating into fibroblastic and lens fiber-like cells. This study aims to show and compare the bio-macromolecular profiles of primary LEC cultures and postoperative lens epithelia LECs on basal laminas (bls), while also analyzing bls and cultured LECs separately. Using synchrotron radiation-based Fourier transform infrared (SR-FTIR) (Bruker, Karlsruhe, Germany) microspectroscopy at the Spanish synchrotron light source ALBA, we observed that the SR-FTIR measurements were predominantly influenced by the strong collagen absorbance of the bls. Cultured LECs on bls showed a higher collagen contribution, indicated by higher vas CH3, CH2 and CH3 wagging and deformation, and the C-N stretching of collagen. In contrast, postoperative LECs on bls showed a higher cell contribution, indicated by the vsym CH2 peak and the ratio between vas CH2 and vas CH3 peaks. The primary difference revealed using SR-FTIR is the greater LEC contribution in spectra recorded from postoperative lens epithelia compared to cultured LECs on bls. IR spectra for bl, cultured LECs and postoperative lens epithelia could be valuable for future research.

PEGylated Micro/Nanoparticles Based on Biodegradable Poly(Ester Amides): Preparation and Study of the Core-Shell Structure by Synchrotron Radiation-Based FTIR Microspectroscopy and Electron Microscopy.

Surface modification of drug-loaded particles with polyethylene glycol (PEG) chains is a powerful tool that promotes better transport of therapeutic agents, provides stability, and avoids their detection by the immune system. In this study, we used a new approach to synthesize a biodegradable poly(ester amide) (PEA) and PEGylating surfactant. These were employed to fabricate micro/nanoparticles with a core-shell structure. Nanoparticle (NP)-protein interactions and self-assembling were subsequently studied by synchrotron radiation-based FTIR microspectroscopy (SR-FTIRM) and transmission electron microscopy (TEM) techniques. The core-shell structure was identified using IR absorption bands of characteristic chemical groups. Specifically, the stretching absorption band of the secondary amino group (3300 cm-1) allowed us to identify the poly(ester amide) core, while the band at 1105 cm-1 (C-O-C vibration) was useful to demonstrate the shell structure based on PEG chains. By integration of absorption bands, a 2D intensity map of the particle was built to show a core-shell structure, which was further supported by TEM images.

Soil amendments alter cadmium distribution and bacterial community structure in paddy soils

Soil amendments play a pivotal role in ensuring the safety of food production by inhibiting the transfer of heavy metal ions from soils to crops. Nevertheless, their impact on soil characteristics and the microbial community and their role in reducing cadmium (Cd) accumulation in rice remain unclear. In this study, pot experiments were conducted to investigate the effects of three soil amendments (mineral, organic, and microbial) on the distribution of Cd speciation, organic components, iron oxides, and microbial community structure. The application of soil amendments resulted in significant reductions in the soil available Cd content (16 %–51 %) and brown rice Cd content (16 %–78 %), facilitating the transformation of Cd from unstable forms (decreasing 10 %–20 %) to stable forms (increasing 77 %–150 %) in the soil. The mineral and organic amendments increased the soil cation exchange capacity (CEC) and plant-derived organic carbon (OC), respectively, leading to reduced Cd accumulation in brown rice, while the microbial amendment enhanced OC complexity and the abundances of Firmicutes and Bacteroidota, contributing to the decreased rice Cd uptake. The synchrotron radiation–based Fourier transform infrared (SR-FTIR) spectroscopy indicated that soil amendments regulated soil Cd species by promoting iron oxides and OC coupling. Moreover, both organic and microbial amendments significantly reduced the diversity and richness of the bacterial communities and altered their compositions and structures, by increasing the relative abundances of Bacteroidota and Firmicutes and decreasing those of Acidobacteria, Actinobacteria, and Myxococcota. Soil microbiome analysis revealed that the increase of Firmicutes and Bacteroidota associated with Cd adsorption and sequestration contributed to the suppression of soil Cd reactivity. These findings offer valuable insights into the potential mechanisms by which soil amendments regulate the speciation and bioavailability of Cd, and improve the bacterial communities, thereby providing guidance for agricultural management practices.

A comprehensive study of sous-vide cooked Korat chicken breast processed by various conditions: texture, compositional/structural changes, and consumer acceptance

Korat chicken (KC), is a slow-growing crossbreed renowned for its excellent growth and firm texture. This study investigated the effect of various sous-vide (SV) conditions (60 and 70°C, 1-3 h) on their texture, protein structure and degradation, as well as consumer acceptability, with the traditional boiling served as control. Texture showed significant improvement under all SV conditions compared to the control, as demonstrated by increased water holding capacity (WHC), cooking loss, and decreased shear force, hardness, and chewiness (P < 0.05). These changes corresponded to the higher sensory scores (P < 0.05). Among the SV samples, increased temperatures and longer cooking times led to higher degradation of myofibrils and connective tissue, as evidenced by a decrease in water-, salt-soluble proteins, and soluble collagen (P < 0.05). These findings aligned with the scanning electron microscopy (SEM) results, which showed a looser muscle structure in the meat under more intense cooking conditions. Based on synchrotron radiation-based Fourier transform infrared (SR-FTIR) results, a gradual increase in antiparallel forms within the amide I bands (1700-1600 cm−1) of the total spectra with higher temperature and longer cooking times was observed (P < 0.05), while the fluctuations were observed in the changes of α-helix, β-sheet, and β-turn structures. This suggested that the antiparallel structure represented a looser configuration developing during intense SV cooking. Combined with the principal component analysis (PCA) results, the findings indicated that the suitable SV condition for KC breast meat was 70°C for varying durations (1-3 h), as it showed the strongest correlation with sensory scores, particularly in terms of tenderness. In summary, these findings provided a better understanding of molecular changes and discovered SV conditions to enhance the texture quality of the KC meat.

Synchrotron‐based Fourier transform infrared microspectroscopy examined differences between the cultured and post‐operative human lens epithelial cells important for understanding posterior capsular opacification and lens regeneration

Aims/Purpose: To compare the bio‐macromolecular composition and the differences between the human cultured and post‐operative lens epithelial cells (LECs) on lens capsules (LCs) for a better understanding of posterior capsular opacification (PCO)—the most common complication of cataract surgery, and lens regeneration.Methods: The explants of the anterior portion of the LC containing the LECs, obtained from cataract surgery and cultivated under adherent conditions, as well as the post‐operative LC with LECs, were analysed by using synchrotron radiation‐based Fourier transform infrared (SR‐FTIR) microspectroscopy, a vibrational spectroscopic technique that allows monitoring of the entire biochemical status of the biological processes. The SR‐FTIR microspectroscopy setup installed on the beamline MIRAS at the Spanish synchrotron light source ALBA was used, where measurements were set to achieve single‐cell resolution, with high spectral stability and high photon flux.Results: We found that the differences exist between the composites of cultured and post‐operative LECs on LCs on the level of all chemical constituents: proteins, lipids, nucleic acids and carbohydrates as well as oxidative stress. The strongest differences are found in protein secondary structure contribution where the composite of primary LECs cultures on LC have more α‐helix (1652 cm−1) and post‐operative LC have more β‐sheet (1624 cm−1 and 1697 cm−1) secondary structures. The oxidative stress is more expressed in the composite of primary LECs cultures on LC and relatively less in the composite of post‐operative lens epithelium LECs on LC.Conclusions: Our results obtained by SR‐FTIR increase the knowledge about the total proteins, lipids, and nucleic acids in human primary cultures LECs while offering also evidence that SR‐FTIR is sensitive to the pathologic processes of LECs transdifferentiation. We showed that the composite of primary cultures LECs on LC have a distinct bio‐macromolecular composition compared to the composite of post‐operative LECs on LC, which gives additional information for a better understanding of PCO and lens regeneration.

Straw mulching decreased the contribution of Fe-bound organic carbon to soil organic carbon in a banana orchard

The association between iron (Fe) oxides (Fe-O) and organic carbon is a vital mechanism for the long-term accumulation and stabilization of soil organic carbon (SOC). To thoroughly explore the impacts of straw mulching on Fe-bound organic carbon (Fe-OC), we conducted a mulching application experiment in a 2-year no-tillage banana orchard. Two treatments (a 2-year straw mulching treatment and no straw return treatment) were established using a randomized complete block design. The Fe-OC and SOC pools in the surface soil were determined, and the results showed that straw mulching significantly increased the SOC contents by 34.02 %, and soil Fe-OC accounted for approximately 12.24 %–25.34 % of the SOC. Compared with the control treatment, straw mulching significantly decreased the Fe-OC contents and their contribution to SOC, which may have been due to soil dithionite-extractable Fe oxide (Fed) contents, the abundance of the Acidibacter, and α-glucosidase activities. Synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy indicated that straw mulching increased the colocalization between cellulose/hemicelluloses and peptides, and the relationships among lignin, Fe-O, and peptides became stronger than those in the CK treatment. These findings imply that straw mulching may decrease Fe-OC pools through various physicochemical and microbial mechanisms, these soil Fe-OC contents may be preserved as lignin derivatives and microbial-derived organic compounds.

Soil conditioners promote the formation of Fe-bound organic carbon and its stability

The close association of soil organic carbon (SOC) with Fe oxides is an important stabilization mechanism for soil organic matter (SOM) against biodegradation. Soil conditioners are of great importance in improving soil quality and soil health. Yet it remains unclear how different conditioners would affect the fractionation of SOC, particularly the Fe-bound organic carbon (Fe-OC). Field-based experiments were conducted in farmland to explore the fractionation of organic carbon (OC) and Fe oxides under the effects of three different soil conditioners (mineral, organic, and microbial conditioners). The results showed that all soil conditioners increased the total OC and Fe-OC contents, with the contribution of Fe-OC to total OC increasing from 1.57% to 2.99%. The low OC/Fe molar ratio indicated that surface adsorption played a crucial role in soil Fe-OC accumulation. Nuclear magnetic resonance (NMR) results suggested that soil conditioner altered the composition of SOM, accelerating O-alkyl C degradation and increasing recalcitrant alkyl C and aromatic C sequestration. Scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) analysis indicated that all conditioners promoted the association of OC and Fe oxides. Furthermore, comprehensive analysis of 13C isotope and synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy showed that the mineral conditioner enhanced the association of microbial-derived OC and Fe oxides, whereas the organic conditioner increased the association of plant-derived OC with Fe oxides. These findings provide important insights into the potential mechanisms through which soil conditioners regulate the stability of OC and guide agricultural management.

Quantitative biochemical phenotypic heterogeneity of macrophages after myelin debris phagocytosis at a single cell level by synchrotron radiation fourier transform infrared microspectroscopy

During the immuno-inflammatory pathophysiological process of spinal cord injury, traumatic brain injury, and ischemic stroke, macrophages play an important role in phagocytizing and clearing degenerated myelin debris. After phagocytizing myelin debris, the biochemical phenotypes related to the biological function of macrophages show vast heterogeneity; however, it is not fully understood. Detecting biochemical changes after myelin debris phagocytosis by macrophages at a single-cell level is helpful to characterize phenotypic and functional heterogeneity. In this study, based on the cell model of myelin debris phagocytosis by macrophages in vitro, the biochemical changes in macrophages were investigated using Synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy. Infrared spectrum fluctuations, principal component analysis, and cell-to-cell Euclidean distance statistical analysis of specific spectrum regions revealed dynamic and significant changes in proteins and lipids within macrophages after myelin debris phagocytosis. Thus, SR-FTIR microspectroscopy is a powerful identification toolkit for exploring biochemical phenotype heterogeneity transformation that may be of great importance to providing an evaluation strategy for studying cell functions related to cellular substance distribution and metabolism.

Heating temperatures affect meat quality and vibrational spectroscopic properties of slow- and fast-growing chickens

This study determined the effect of water bath cooking (70°C and 90°C for 40 min) and the extreme heat treatment by an autoclave (121°C for 40 min) on the quality of breast meat of a fast-growing chicken, commercial broiler (CB), and slow-growing chickens, Korat chicken (KC), and Thai native chicken (NC) (Leung Hang Khao), by vibrational spectroscopic techniques, including synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy and Fourier transform Raman (FT-Raman) spectroscopy. Taste-enhancing compounds, including inosine-5'-monophosphate (IMP) and guanosine-5'-monophosphate (GMP), were better retained in cooked KC and NC meats than in cooked CB meat (P < 0.05). The high heat treatment at 121°C depleted the amount of insoluble collagen in all breeds (P < 0.05). Shear force values of slow-growing chicken meat were not affected by high heating temperatures (P > 0.05). In addition, the high heat treatment increased protein carbonyl (P < 0.05), while no effect on in vitro protein digestibility (P > 0.05). SR-FTIR microspectroscopy performed better in differentiating the meat quality of different chicken breeds, whereas FT-Raman spectroscopy clearly revealed differences in meat qualities induced by heating temperature. Based on principal component analysis (PCA), distinct characteristics of chicken meat cooked at 70°C were high water-holding capacity, lightness (L*), moisture content, and predominant α-helix structure, correlating with Raman spectra at 3,217 cm-1 (O-H stretching of water) and 1,651 cm-1 (amide I; α-helix). The high heating temperature at 90°C and 121°C exposed protein structure to a greater extent, as evidenced by an increase in β-sheets, which was well correlated with the Raman spectra at 2,968 and 2,893 cm-1 (C-H stretching), tryptophan (880 cm-1), tyrosine (858 cm-1), and 1,042, 1,020, and 990 cm-1 (C-C stretching; β-sheet). SR-FTIR and FT-Raman spectroscopy show potential for differentiation of chicken meat quality with respect to breeds and cooking temperatures. The marked differences in wavenumbers would be beneficial as markers for determining the quality of cooked meats from slow- and fast-growing chickens.

Efficient controlled release of cannabinoids loaded in γ-CD-MOFs and DPPC liposomes as novel delivery systems in oral health

Olivetol (OLV), as a cannabidiol (CBD) analog, was incorporated in γ-cyclodextrin metal-organic frameworks (γ-CD-MOFs) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes as potential analgesic drug delivery systems (DDS) for dental hypersensitivity (DH) treatment. These DDS have been scarcely employed in oral health, being the first time in case of MOFs loaded with cannabinoids. In vitro experiments using bovine teeth were performed to verify if the drug is able to reach the dentin, where it can flow to the pulp tissues and exert its analgesic effect; enamel and dentin regions were analyzed by synchrotron radiation-based FTIR microspectroscopy. Principal component analysis (PCA) was used to process the spectroscopic data as a powerful chemometric tool, and it revealed a similar behavior in both regions. The studied DDS have been characterized by different techniques, and is was demonstrated that DDS is an efficient way to carry the drug through dental tissues without compromising their structure.Graphical

Investigating the Effect of Various Sous-Vide Cooking Conditions on Protein Structure and Texture Characteristics of Tilapia Fillet Using Synchrotron Radiation-Based FTIR.

The effects of various sous-vide (SV) cooking conditions (50-60℃, 30-60 min) on physicochemical properties related to the texture characteristics, protein structure/degradation, and sensory acceptability of tilapia fillet (Oreochromis niloticus) were investigated. With an increasing temperature and processing time of SV cooking, protein degradation (of both myofibrils and connective tissue) was more pronounced, as evaluated by the decrease in water- and salt-soluble proteins, total collagen, as well as the changes in the ratio of secondary protein structures (α-helix, β-sheet, β-turn, etc.), which were determined by synchrotron-FTIR (SR-FTIR). These degradations were associated with the improvement of meat tenderness, as estimated by shear force and texture profile analyzer (TPA) results. Among all SV conditions, using 60 ℃ for 45 min seems to be the optimal condition for tilapia meat, since it delivered the best results for texture characteristics and acceptability (p < 0.05). Moreover, principal component analysis (PCA) results clearly demonstrated that the highest texture-liking score of this condition was well associated with the intensity of β-sheets, which seem to be the crucial component that affected the texture of SV-cooked tilapia more so than other parameters. The findings demonstrated the potential of SR-FTIR to decipher the biomolecular structure, particularly the secondary protein structure, of SV-cooked tilapia. This technique provided essential information for a better understanding of the changes in biomolecules related to the textural characteristics of this product.

Biomacromolecular Profile in Human Primary Retinal Pigment Epithelial Cells—A Study of Oxidative Stress and Autophagy by Synchrotron-Based FTIR Microspectroscopy

Synchrotron radiation-based Fourier Transform Infrared (SR-FTIR) microspectroscopy is a non-destructive and chemically sensitive technique for the rapid detection of changes in the different components of the cell's biomacromolecular profile. Reactive oxygen species and oxidative stress may cause damage to the DNA, RNA, and proteins in the retinal pigment epithelium (RPE), which can further lead to age-related macular degeneration (AMD) and visual loss in the elderly. In this study, human primary RPEs (hRPEs) were used to study AMD pathogenesis by using an established in vitro cellular model of the disease. Autophagy-a mechanism of intracellular degradation, which is altered during AMD, was studied in the hRPEs by using the autophagy inducer rapamycin and treated with the autophagy inhibitor bafilomycin A1. In addition, oxidative stress was induced by the hydrogen peroxide (H2O2) treatment of hRPEs. By using SR-FTIR microspectroscopy and multivariate analyses, the changes in the phosphate groups of nucleic acids, Amide I and II of the proteins, the carbonyl groups, and the lipid status in the hRPEs showed a significantly different pattern under oxidative stress/autophagy induction and inhibition. This biomolecular fingerprint can be evaluated in future drug discovery studies affecting autophagy and oxidative stress in AMD.

Synchrotron Radiation FTIR Microspectroscopy Study of Biomolecular Alterations in Vincristine-Treated WRL68 Cells at the Single-Cell Level.

The toxic effect of vincristine on hepatocytes has rarely been studied. Synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy is a novel technique for investigating drug-cell interaction systems. In this research, the biomolecular alterations in WRL68 cells induced by vincristine treatment were investigated by SR-FTIR microspectroscopy and were further analyzed by multivariate statistical analysis and semiquantitative methods, including principal component analysis (PCA), orthogonal partial least square-discriminant analysis (OPLS-DA), and the peak area ratios of several characteristic IR bands. In vincristine-treated WRL68 cells, alterations in lipid structures and the presence of more long-chain fatty acids were found. A decrease in protein α-helical content relative to β-sheet structures in vincristine-treated WRL68 cells was identified. The nucleic acid content was decreased relative to that of lipids and proteins in WRL68 cells treated with vincristine. These results provide important information about the toxic effect of vincristine on normal liver cells. This research also provides a new approach to reveal the biomolecular alterations in drug-treated hepatocytes by combining SR-FTIR with multivariate statistical analysis and semiquantitative methods.

Synchrotron radiation‐based infrared micro‐spectroscopy characterization of different types of epiretinal proliferations

AbstractPurpose: To assess epiretinal proliferations bio‐macromolecules and to provide their molecular fingerprint for better understanding of epiretinal proliferations, we used synchrotron radiation‐based Fourier transform infrared (SR‐FTIR) micro‐spectroscopy.Methods: The membranes were collected from routine pars plana vitrectomy. The biochemical differences between idiopathic nonvascular epiretinal membranes (ERMi), membranes in proliferative vitreoretinopathy (PVRm) and neovascular membranes in proliferative diabetic retinopathy (PDRm) were evaluated and compared by using SR‐FTIR micro‐spectroscopy at the MIRAS beamline of the ALBA Synchrotron, Barcelona, Spain and multivariate analysis.Results: PVRm differs the most from ERMi and PDRm in all spectral regions. We demonstrated the presence of silicone oil (SO) or polydimethylsiloxane (PDMS) in the structure of PVRm membrane after SO endotamponade suggesting that SO, in addition to many benefits as an important tool in vitreoretinal surgery, can also contribute in PVRm formation. We also showed the differences between PVRm, PDRm and ERMi in protein and lipid structure, collagen content and maturity.Conclusions: Our results obtained by SR‐FTIR increase the knowledge about the total proteins, lipids and nucleic acids in different epiretinal proliferations while offering also the evidence that SR‐FTIR is sensitive to the pathologic processes of epiretinal proliferations. We emphasize the different macro‐molecular composition of three different types of epiretinal proliferation stemming from different components and metabolic processes taking place as well as the caution needed when using SO in vitreoretinal surgery.

Synchrotron-Radiation-Based Fourier Transform Infrared Microspectroscopy as a Tool for the Differentiation between Staphylococcal Small Colony Variants.

Small colony variants (SCVs) are clinically significant and linked to persistent infections. In this study, synchrotron-radiation-based Fourier transform infrared (SR-FTIR) is used to investigate the microspectroscopic differences between the SCVs of Staphylococcus aureus (S. aureus) and diabetic foot Staphylococcus epidermidis (S. epidermidis) in two main IR spectral regions: (3050-2800 cm-1), corresponding to the distribution of lipids, and (1855-1500 cm-1), corresponding to the distribution of protein amide I and amide II and carbonyl vibrations. SR-FTIR successfully discriminated between the two staphylococcal species and between the SCV and the non-SCV strains within the two IR spectral regions. Combined S. aureus SCVs (SCVhMu) showed a higher protein content relative to the non-SCV wild type. Complemented S. aureus SCV showed distinguishable differences from the SCVhMu and the wild type, including a higher content of unsaturated fatty acids. An increase in the CH2/CH3 ratio was detected in S. epidermidis SCV samples compared to the standard control. Protein secondary structure in standard S. epidermidis and SCVs consisted mainly of an α-helix; however, a new shoulder at 1635 cm-1, assigned to β-sheets, was evident in the SCV. In conclusion, SR-FTIR is a powerful method that can discriminate between staphylococci species and to differentiate between SCVs and their corresponding natural strains.

Synchrotron radiation-based Fourier transform infrared microspectroscopy investigation of WRL68 cells treated with doxorubicin

Doxorubicin is an effective chemotherapeutic agent applied in a wide variety of cancers. Despite its potent anticancer activity towards cancer cells, doxorubicin is also toxic to noncancerous cells. Therefore, doxorubicin can cause serious side effects in various organs, especially when dose escalation is required for patients with advanced disease. The liver is the major detoxification organ that metabolizes drugs, and hepatotoxicity is one of the most common adverse effects of doxorubicin administration. However, the exact mechanisms of doxorubicin-induced hepatotoxicity have not been clearly identified, and how doxorubicin treatment affects the biomolecular contents of normal human hepatocytes has rarely been studied. Synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy is a state-of-the-art analytical technique for characterizing the biomolecules present in cells. In this research, the biomolecular alterations of doxorubicin-treated normal human hepatocytes compared to untreated control cells were investigated at the single-cell level by combining SR-FTIR microspectroscopy with the Cell Counting Kit-8 (CCK-8) assay and flow cytometry. WRL68 human normal embryonic liver cells, which have been shown to be very promising for assessing the cytotoxicity of toxic compounds and investigating hepato-toxicology, were used in this research. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were used to further analyse the biomolecular contents of WRL68 cells. The order of lipid acyl chains and protein α-helix structures in doxorubicin-treated WRL68 cells was found to be distinctly changed, while the nucleic acids were altered relatively less. No alteration in the carbohydrate content was distinguishable after doxorubicin treatment. These results provide more comprehensive information about the biomolecular changes in hepatocytes induced by doxorubicin treatment and help to elucidate the mechanism of doxorubicin-induced hepatotoxicity. This research also proves that SR-FTIR microspectroscopy, combined with PCA and OPLS-DA, is a promising approach for investigating drug-cell interaction systems.

Effects of Extraction Processes on the Oxidative Stability, Bioactive Phytochemicals, and Antioxidant Activity of Crude Rice Bran Oil.

This research investigates the effects of different extraction processes on the oil extractability, oxidative stability, bioactive compounds, and antioxidant activity of crude rice bran oil (CRBO). The experimental extraction processes include hexane extraction (HE), cold press extraction (CE), thermally pretreated cold press extraction (CCE), and ultrasound-pretreated cold press extraction (UCE). The results show that thermal cooking and ultrasound pretreatment significantly improve the oil extractability of the cold press extraction process. The oil yields of CE, CCE, and UCE were 14.27, 17.31, and 16.68 g oil/100 g rice bran, respectively. The oxidative stability of CE and CCE oils was higher than HE and UCE oils, as evidenced by the synchrotron-radiation-based Fourier transform infrared (SR-FTIR) absorption peak. The ρ-anisidine values of HE, CE, CCE, and UCE were 0.30, 0.20, 0.91, and 0.31, respectively. Meanwhile, ultrasound pretreatment significantly reduced the bioactive compounds and chemical antioxidant activity of UCE oil. The CE, CCE, and UCE oils (0.1% oil concentration) exhibited higher inhibitory effects against hydrogen-peroxide-induced cellular oxidative stress, compared to HE oil (0.39% oil concentration). Essentially, CCE is operationally and environmentally suitable for improving the oil yield, oxidative stability, bioactive compounds, and antioxidant activities of CRBO.

New strategy for exploring the accumulation of heavy metals in soils derived from different parent materials in the karst region of southwestern China

Heavy metals with high average background values in soils from karst regions of China have been reported previously. However, the accumulation mechanism of heavy metals in karst soils derived from different parent materials related to the molecular soil chemistry is still unclear. In this study, six soil cores (0–100 cm) from three locations were collected from Hengxian County, a typical karst basin of Guangxi, among which soils of Maling (ML1 and ML2) were derived from the weathering and leaching residues of carbonate rocks, and soils of Yunbiao (YB1 and YB2) and Dengxu (DX1 and DX2) were mainly developed from deposits of Quaternary formations. Soil heavy metal quantification, X-ray diffraction (XRD) analysis, synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy, and two-dimensional correlation spectroscopy (2DCOS) analysis were combined to study the contents of heavy metals, mineral compositions, and functional assignments in the karst soils. The results showed that the total concentrations of As, Cr, Cd, Cu, Ni, Pb, and Zn in the soils from ML exceeded the risk screening values from the agricultural soil quality standard in China (GB15618-2018), while the contents in the soils from YB and DX were below the risk screening values. The mineral components were significantly different in soils and their clay minerals. ML soils contained more Fe and Mn oxides than YB and DX soils. Furthermore, it was interesting to find extensive existence of chlorite in ML soils (36.73%-39.07%) and their clay minerals (90.49%-90.97%). While illite was the dominant mineral in YB and DX clay fractions (75.08%-100%) and its percentages decreased to 6.06%-35.23% in the soil samples. In addition, ML soils contained the hydroxyl groups with hydrogen bonds (vO-H: 3523, 3450, and 3378 cm−1) and the hydroxyl groups without hydrogen bonds (vO-H: 3698, 3623 cm−1), while YB and DX soils only had the hydroxyl groups without hydrogen bonds (vO-H: 3695, 3622 cm−1). Our study indicated that the accumulation of heavy metals in karst soils from different parent materials was significantly attributed to their molecular soil chemistry. For instance, the higher contents of Fe-Mn oxides and more reactive vO-H (3523, 3450, and 3378 cm−1) and vSi-O (1000 cm−1) assignments could contribute to the higher contents of heavy metals in ML soils compared to the soils from YB and DX.

A comparative study of meat quality and vibrational spectroscopic properties of different chicken breeds

Chicken breed is one of the key factors that influence meat quality. The quality attributes of breast meat from commercial broiler (CB), Thai native chicken (NC, Leung Hang Khao), and the crossbred Korat chicken (KC) were investigated via synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy, Fourier transform Raman (FT-Raman) spectroscopy, and physicochemical analysis. The protein and carbonyl contents of KC and NC meats were higher than that of CB meat, but the lipid content was lower (P < 0.05). CB meat was characterized by high moisture, lightness (L*), and presence of taste-active nucleotides, namely, inosine 5′-monophosphate (IMP) and guanosine 5′-monophosphate (GMP). Moreover, NC meat had the highest insoluble collagen and inosine contents (P < 0.05). The predominant protein secondary structures of KC and NC meats were β-turns and random coils, whereas α-helices were mainly found in CB meat. Based on principal component analysis, the meat quality and spectra were clearly separated by breeds. The high moisture and lipid content of meat corresponded to O–H stretching (3,203 cm−1) and C–H stretching (2,854 cm−1) in the FT-Raman spectra, whereas PO2− stretching (1,240 cm−1), measured via SR-FTIR, was well correlated with the IMP content. In addition, the FT-Raman wavenumber of 934 cm−1, indicating C–C stretching, was correlated with high water-holding capacity (WHC) in KC meat. The quality of meat from slow- and fast-growing chickens significantly varies. Vibrational spectroscopy is a powerful technique that provides insightful molecular information correlated with various meat attributes.

Lipid Status of A2780 Ovarian Cancer Cells after Treatment with Ruthenium Complex Modified with Carbon Dot Nanocarriers: A Multimodal SR-FTIR Spectroscopy and MALDI TOF Mass Spectrometry Study.

Simple SummaryDeveloping new anticancer medicaments is focused on inducing controlled elimination of tumor tissue without severe side effects. It is essential to enable the medicament to reach the target molecule without provoking the immune response too early. The first cellular changes might occur already at the level of the cell membrane, composed mainly of lipids. Therefore, we used spectroscopic techniques to study the interaction of potential metallodrug [Ru(η5-C5H5)(PPh3)2CN] (RuCN) with lipids of A2780 ovarian cancer cells and investigated if these changes are affected by the presence of drug carriers (carbon dots (CDs) and nitrogen-doped carbon dots (N-CDs)). Our results showed that CDs and N-CDs prevent lysis and moderate oxidative stress of lipids caused by metallodrug, still keeping the antitumor activity and potential to penetrate through the lipid bilayer. Therefore, Ru drug loading to carriers balances the anticancer efficiency and leads to better anticancer outcomes by reducing the oxidative stress that has been linked to cancer progression.In the last decade, targeting membrane lipids in cancer cells has been a promising approach that deserves attention in the field of anticancer drug development. To get a comprehensive understanding of the effect of the drug [Ru(η5-Cp)(PPh3)2CN] (RuCN) on cell lipidic components, we combine complementary analytical approaches, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) and synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy. Techniques are used for screening the effect of potential metallodrug, RuCN, without and with drug carriers (carbon dots (CDs) and nitrogen-doped carbon dots (N-CDs)) on the lipids of the human ovarian cancer cell line A2780. MALDI TOF MS results revealed that the lysis of ovarian cancer membrane lipids is promoted by RuCN and not by drug carriers (CDs and N-CDs). Furthermore, SR-FTIR results strongly suggested that the phospholipids of cancer cells undergo oxidative stress after the treatment with RuCN that was accompanied by the disordering of the fatty acid chains. On the other hand, using (N-)CDs as RuCN nanocarriers prevented the oxidative stress caused by RuCN but did not prevent the disordering of the fatty acid chain packing. Finally, we demonstrated that RuCN and RuCN/(N-)CDs alter the hydration of the membrane surface in the membrane–water interface region.