Phospholipid biosynthesis modulates nucleotide metabolism and reductive capacity.

Phospholipid and nucleotide syntheses are fundamental metabolic processes in eukaryotic organisms, with their dysregulation implicated in various disease states. Despite their importance, the interplay between these pathways remains poorly understood. Using genetic and metabolic analyses in Saccharomyces cerevisiae, we elucidate how cytidine triphosphate usage in the Kennedy pathway for phospholipid synthesis influences nucleotide metabolism and redox balance. We find that deficiencies in the Kennedy pathway limit nucleotide salvage, prompting compensatory activation of de novo nucleotide synthesis and the pentose phosphate pathway. This metabolic shift enhances the production of antioxidants such as NADPH and glutathione. Moreover, we observe that the Kennedy pathway for phospholipid synthesis is inhibited during replicative aging, indicating its role in antioxidative defense as an adaptive mechanism in aged cells. Our findings highlight the critical role of phospholipid synthesis pathway choice in the integrative regulation of nucleotide metabolism, redox balance and membrane properties for cellular defense.

Ultrasound-assisted glycation and the allergenicity of α-lactalbumin.

BACKGROUND: Ultrasound-assisted glycation is a promising method for decreasing the allergenicity of α-lactalbumin (ALA). However, there is a lack of in vivo studies on the allergenicity of ultrasound-assisted glycated ALA. In this study, the effects of the ultrasound-assisted glycation of ALA on the allergenicity and intestinal microflora were characterized using a BALB/c mouse model. RESULTS: Increased immunoglobulin -G/ immunoglobulin-E (IgG/IgE) and interleukin-4/6 (IL-4/6) secretions, and reduced interferon-γ (IFN-γ) secretions were found in the serum of ALA sensitized and challenged, mice in comparison with a control group. However, there was no significant difference between the mice fed with ultrasound-assisted glycated ALA and the control group. Mice that were sensitized and challenged with ALA showed disrupted intestinal microflora, manifesting in significantly decreased Firmicutes and significantly increased Proteobacteria. It was found that 100ALA-gal could maintain the intestinal microflora of mice in a normal state. Pearson's rank correlation showed that Proteobacteria and Spirochaetota were correlated positively with the IL-4/IL-6 level and were correlated negatively with the expression of IFN-γ. Proteobacteria were also significantly positively correlated with IL-6 and negatively correlated with IFN-γ (P < 0.05). CONCLUSION: These results suggested that ultrasound-assisted glycation on ALA can maintain the intestinal microflora in a normal state thus balancing the proportion of Th1/Th2 to decrease allergic reaction. © 2022 Society of Chemical Industry.

Set of Cytochrome P450s Cooperatively Catalyzes the Synthesis of a Highly Oxidized and Rearranged Diterpene-Class Sordarinane Architecture.

Cytochrome P450s are one of the most versatile oxidases that catalyze significant and unique chemical transformations for the construction of complex structural frameworks during natural product biosynthesis. Here, we discovered a set of P450s, including SdnB, SdnH, SdnF, and SdnE, that cooperatively catalyzes the reshaping of the inert cycloaraneosene framework to form a highly oxidized and rearranged sordarinane architecture. Among them, SdnB is confirmed to be the first P450 (or oxidase) that cleaves the C-C bond of the epoxy residue to yield formyl groups in pairs. SdnF selectively oxidizes one generated formyl group to a carboxyl group and accelerates the final Diels-Alder cyclization to furnish the sordarinane architecture. Our work greatly enriches the enzyme functions of the P450 superfamily, supplies the missing skills of the P450 synthetic toolbox, and supports them as biocatalysts in further applications toward the synthesis of new chemical entities.

Anti-inflammatory Dimeric Benzophenones from an Endophytic Pleosporales Species.

Eight new polyketides, including three dimeric benzophenones, named dipleosporones A-C (1-3), three benzophenones (4-6), one xanthone (7), and one phenylbenzoate (8), along with seven known polyketides (9-15) were isolated from the fungus Pleosporales sp. YY-4. The structures of the new compounds were established on the basis of spectroscopic methods, including high-resolution electrospray ionization mass spectrometry and one- and two-dimensional nuclear magnetic resonance. This is the first report of a benzophenone dimer connection via a C bridge from natural sources. An anti-inflammatory assay indicated that the dimeric benzophenones (1-3) inhibited lipopolysaccharide-induced NO production in RAW 264.7 cells, with half-maximal inhibitory concentration (IC50) values ranging from 8.8 to 18.1 µM, being more potent than the positive control, dexamethasone (IC50 = 22.2 µM).

Flavor, antimicrobial activity and physical properties of gelatin film incorporated with of ginger essential oil.

Adding essential oil into the gelatin-based film can enhance the antibacterial activity of the film, but excessive amounts of addition will bring the film an unpleasant flavor and reduce its mechanical performance. Hence, we prepared functional gelatin-based films by incorporating low content of ginger essential oil (GEO). The flavor of GEO was not detected from the films containing less than 1% GEO. The antimicrobial activity of films was found to be proportional to GEO content. As GEO content increased from 0 to 1%, the value of water vapor permeability (WVP) and elongation at break (EAB) increased, whereas the value of tensile strength (TS) of film decreased. The Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy analysis revealed the vibration of gelatin film was affected by adding low content of essential oil. Surface morphologies demonstrated oil droplets and a discontinuous structure, and cross-section morphologies proved the formation of a loose structure as GEO was incorporated in the film through SEM. Sensory evaluation revealed that composite films incorporated with 0.5% GEO exhibited the best performance. The resulting films can be used as antimicrobial packaging materials with good physical properties and sensory performance.

Effects of ultrasound on functional properties, structure and glycation properties of proteins: a review.

Protein is an indispensable part of life. It provides nutrition for human body and flavor for food. The role of protein depends largely on the functional properties of the protein. Therefore, the elucidation of protein structure and functional properties needs to be further explored. The effects of structural and functional properties of proteins under different ultrasonic treatment conditions were reviewed. The structural changes of protein were studied by hydrogen-deuterium exchange mass spectrometry combined with fluorescence spectrometry and proteomics, and the mechanism of action was determined. The glycation site, the glycation degree, and the glycation characteristics of different sugars were determined. The protein was modified by ultrasound, and the influence of protein structure, physicochemical properties, protein glycation characteristics, and the action mechanism were analyzed by biological mass spectrometry.

Aromatic Cadinane Sesquiterpenoids from the Fruiting Bodies of Phellinus pini Block SARS-CoV-2 Spike-ACE2 Interaction.

The ongoing COVID-19 global pandemic caused by SARS-CoV-2 inspires the development of effective inhibitors to block the SARS-CoV-2 spike-ACE2 interaction. A chemical investigation on the fruiting bodies of Phellinus pini led to the isolation of five aromatic cadinane sesquiterpenoids including four new ones, named piniterpenoids A-D (1-4), as well as three known lignans. Their structures were determined by extensive spectroscopic analysis including HRMS and 1D and 2D NMR. All of the aromatic cadinane sesquiterpenoids inhibited the SARS-CoV-2 spike-ACE2 interaction, with IC50 values ranging from 64.5 to 99.1 µM. A molecular docking study showed the disruption of the interaction of compound 1 via hydrogen interactions with Arg403, Asp405, and Arg408 of SARS-CoV-2 RBD and Arg393 and His34 residues of ACE2. These results suggested that aromatic cadinane sesquiterpenoids might be useful in developing agents for COVID-19.

The reduction in the immunoglobulin G and immunoglobulin E binding capacity of ß-lactoglobulin via spray-drying technology.

Bovine ß-lactoglobulin (ß-LG) is the major allergen in milk powder. The IgG/IgE binding capacity and structural characteristics of ß-LG after spray drying in the presence or absence of α-lactose at 120 and 180°C were investigated by ELISA and mass spectrometry. At a drying temperature of 120°C, no change was found in the IgG/IgE binding capacity of ß-LG and no change was observed in free amino group content, fluorescence intensity, or detectable glycation. At a drying temperature of 180°C, aggregation of ß-LG occurred, leading to a decrease in the IgG/IgE binding capacity. When α-lactose was also present, 7 lysine side-chains in ß-LG were modified by glycation and the IgG/IgE binding capacity was further decreased. Therefore, the glycation and structural changes in ß-LG were responsible for the reduction in the IgG/IgE binding capacity during high temperature (180°C) spray drying.

Ultrasound-Assisted Extraction Optimization of α-Glucosidase Inhibitors from Ceratophyllum demersum L. and Identification of Phytochemical Profiling by HPLC-QTOF-MS/MS.

Ceratophyllum demersum L. (CDL) is a traditional Chinese herb to treat many diseases, but research on its anti-diabetic activity is not available. In this research, the α-glucosidase inhibitory ability and phytochemical constituents of CDL extract were firstly studied. Optimal ultrasound-assisted extraction conditions for α-glucosidase inhibitors (AGIs) were optimized by single factor experiment and response surface methodology (RSM), which was confirmed as 70% methanol, liquid-to-solid ratio of 43 (mL/g), extraction time of 54 min, ultrasonic power of 350 W, and extraction temperature of 40 °C. The lowest IC50 value for α-glucosidase inhibition was 0.15 mg dried material/mL (mg DM/mL), which was much lower than that of acarbose (IC50 value of 0.64 mg DM/mL). In total, 80 compounds including 8 organic acids, 11 phenolic acids, 25 flavonoids, 21 fatty acids, and 15 others were identified or tentatively identified from CDL extract by HPLC-QTOF-MS/MS analysis. The results suggested that CDL could be a potential source of α-glucosidase inhibitors. It can also provide useful phytochemical information for research into other bioactivities.

The accumulation, histopathology, and intestinal microorganism effects of waterborne cadmium on Carassius auratus gibelio.

Cadmium (Cd) is known to be a potentially toxic heavy metals to the fish health and growth. Carassius auratus gibelio (C. a. gibelio) specimens were exposed to waterborne Cd (0, 0.05, 0.10, 0.15, and 0.20 mg/L CdCl2) for 14 days. Cd accumulation, liver and intestine histopathology, and intestinal microorganism were investigated in the present study. The results indicated that Cd accumulation in the gill, liver, intestine, and muscle gradually decreased as Cd concentration increased. The gill accumulated higher amounts of Cd than other tissues. The histopathology of liver and intestine underwent changes with different Cd concentrations, including hepatocyte hypertrophy, aggregation of blood cells, sinusoids, lipidosis, necrosis of hepatic tissues, the erosion of villi, necrosis in the mucosal layer, the appearance of vacuoles in the lamina propria, hyperplasia, and swelling of goblet cells. Moreover, the core gut microbiota existed in the intestinal microorganism and did not change as Cd concentration increased. However, the diversity of intestinal microorganism was significantly reduced compared with that of the control sample. The present results indicated that C. a. gibelio exposed to Cd suffered toxicity, and Cd could affect the biodiversity of the intestinal microbiota of C. a. gibelio.

Glycation of ovalbumin after high-intensity ultrasound pretreatment: effects on conformation, immunoglobulin (Ig)G/IgE binding ability and antioxidant activity.

BACKGROUND: Ovalbumin (OVA), a protein with excellent nutritional and processing properties, is the major allergen of hen egg white. High-intensity ultrasound treatment increases the immunoglobulin (Ig)G and IgE binding abilities by unfolding the conformational structure of OVA. This may allow a modification of the IgG and IgE binding of OVA by combining high-intensity ultrasound with other methods, such as glycation, thus representing a promising method for the improvement of protein properties. RESULTS: Glycation with mannose (M) after ultrasound pretreatment at 0-600 W significantly reduced the IgG and IgE binding abilities and dramatically enhanced the antioxidant activity of OVA-M conjugates, with the lowest values of IgG and IgE binding and highest values of antioxidant capacity observed at 600 W. Polyacrylamide gel electrophoresis showed that the molecular weight of OVA-M conjugates with ultrasound pretreatment increased more than non-pretreatment sample, implying that ultrasound pretreatment promoted glycation. The α-helix content and ultraviolet absorption of OVA were observably increased, whereas ß-sheet content, intrinsic fluorescence and surface hydrophobicity were notably decreased, indicating that the tertiary and secondary structures of OVA were markedly changed. CONCLUSION: High-intensity ultrasound pretreatment can be conducive to reducing the binding abilities of IgG and IgE and enhancing the antioxidant activity of OVA-M conjugates. Therefore, glycation combined with high-intensity ultrasound pretreatment might be a promising method for producing hypo-allergenic and high-antioxidant OVA products. © 2018 Society of Chemical Industry.

Gelation kinetics and characterization of enzymatically enhanced fish scale gelatin-pectin coacervate.

BACKGROUND: Protein-polysaccharide complex coacervations have been considered extensively for the development of functional foods. The main problem of the complex coacervates is that they are highly unstable under different conditions and that cross-linking is necessary to stabilize them. In this study, the effects of pectin at different concentrations on the gel and structural properties of fish scale gelatin (FSG)-high methoxyl citrus pectin (HMP) coacervate enhanced by microbial transglutaminase (MTGase) were studied. RESULTS: The gelation rates and gel strength of the MTGase-enhanced FSG-HMP coacervate gels decreased with increasing HMP concentration. However, the enhanced coacervate gels exhibited better thermal behavior and mechanical properties compared with the original gels. Also, TG-P8 exhibited the highest melting point (27.15 ± 0.12 °C), gelation point (15.65 ± 0.01 °C) and stress (15.36 ± 0.48 kPa) as HMP was 8 g kg-1 . Particle size distribution, fluorescence emission and UV absorbance spectra indicated that MTGase and HMP could make FSG form large aggregates. Moreover, confocal laser scanning microscopy of treated coacervate gels showed a continuous protein phase at low HMP concentrations. CONCLUSION: FSG and HMP could form soluble coacervate, and MTGase could improve the thermal and mechanical properties of coacervate gels. © 2017 Society of Chemical Industry.

High-intensity ultrasound enhances the immunoglobulin (Ig)G and IgE binding of ovalbumin.

BACKGROUND: Hen eggs are widely used in food industry as a result of their excellent nutritional and processing properties and ovalbumin (OVA) is the major allergen of hen egg whites. Ultrasound has been widely used in the food processing industry, although the effect of high-intensity ultrasound on the immunoglobulin (Ig)G binding, IgE binding and conformational structure of OVA remains unclear. RESULTS: Ultrasound treatment at 600-800 W dramatically increased the IgG and IgE binding of OVA, with the highest values observed at 600 W. The free sulfhydryl content, surface hydrophobicity and ultraviolet absorption were gradually increased when the power was increased from 200 to 600 W, implying the occurrence of molecule unfolding. When the power was 800 W, the binding ability was slightly decreased and was associated with the aggregation of OVA molecules. Polyacrylamide gel electrophoresis analysis implied that ultrasound treatment at 800 W could induce the aggregation of OVA molecules via disulfide bonds and/or hydrophobic interactions. CONCLUSION: High-intensity ultrasound can increase the potential allergenicity of OVA. Therefore, high-intensity ultrasound processing of some egg products alone may improve the risk of an allergenic reaction in egg allergy patients to some extent. © 2016 Society of Chemical Industry.

Comparison of rheological behaviors and nanostructure of bighead carp scales gelatin modified by different modification methods.

In this study, microbial transglutaminase (MTGase) and pectin were compared to modify bighead carp (Hypophthalmichthys nobilis) scale gelatin. The functional properties of modified fish scales gelatin (FSG) were largely improved, including melting temperature and rheological behavior. While, modification methods decreased the triple-helix content and destroyed the single left-hand helix chain of modified FSG as investigated by X-ray diffraction. MTGase could induce the denser and finer gels network, but had none significant effect on nanostructural properties of fish gelatin. Pectin inserted itself into the fish gelatin gels network and caused aggregations, forming crystalline peaks and various nanostructures. In particular, compared with pectin modified FSG, MTGase produced FSG with lower storage modulus and apparent viscosity, but higher gel points and melting points.

The adsorption of lead(II) ions by dynamic high pressure micro-fluidization treated insoluble soybean dietary fiber.

Insoluble dietary fiber from soybean residue (SIDF) was treated with dynamic high-pressure microfluidization (DHPM) and used as adsorbent for Pb(II) ion. The effects of pressure on the Pb(II) adsorption capacity, primary cilia structure and surface topography of SIDF were determined using a gastrointestinal simulated model in vitro. SIDF (at pH 7.0) showed maximum binding capacity (261.42 ± 2.77 µmol/g), which was about 1.13 times higher than that of untreated sample (233.47 ± 1.84 µmol/g), when pressure reached 80 MPa. However, the net adsorption value of SIDF in a simulated small intestine (~ 9 µmol/g) was significantly lower than that in the stomach (~ 48 µmol/g), because of the competitive adsorption of Pb(2+) by pancreatin, cholate and several enzymes in the small intestine. In addition, the adsorption capacity of SIDF exhibited good linear relationship with the physicochemical properties of total negative charges, and the adsorption behavior presumably occurred on the surface area of granules fiber.

Quality evaluation of peony seed oil spray-dried in different combinations of wall materials during encapsulation and storage.

This study aimed at evaluating the performance of peony seed oil microencapsulated by spray drying during encapsulation and storage. Four different combinations of gum arabic (GA), corn syrup (CS), whey protein concentrate (WPC) and sodium caseinate (CAS) were used to encapsulate peony seed oil. The best encapsulation efficiency was obtained for CAS/CS followed by the CAS/GA/CS combination with the encapsulation ratio of 93.71 and 92.80 %, respectively, while the lowest encapsulation efficiency was obtained for WPC/GA/CS (85.96 %). Scanning electron microscopy and confocal laser scanning microscopy revealed that the particles were spherical in shape and did not exhibit apparent cracks or fissures, and gum arabic was uniformly distributed across the wall of the microcapsules. Oxidative stability study indicated that the CAS/GA/CS combination presented the best protection against lipid oxidation and the smallest loss of polyunsaturated fatty acid content among all of the formulas as measured by gas chromatography. Therefore, CAS/GA/CS could be promising materials encapsulate peony seed oil with high encapsulation efficiency and minimal lipid oxidation.

The effect of ginger and garlic addition during cooking on the volatile profile of grass carp (Ctenopharyngodon idella) soup.

Ginger and garlic have long been used in Asian countries to enhance the flavor and to neutralize any unpleasant odors present in fish soup. The purpose of this study was to evaluate the change in the amount of volatile components present in fish soup compared to boiled water solutions of ginger and garlic. The fish soup was prepared by boiling oil-fried grass carp (Ctenopharyngodon idella) with or without ginger and/or garlic. Generally, boiling garlic and ginger in water led to a decrease in the amount of the principal volatile constituents of these spices, together with the formation of some new volatiles such as pentanal, hexanal, and nonanal. The results showed that 16 terpenes present in raw ginger, predominantly camphene, ß-phellandrene, ß-citral, α-zingiberene, and (E)-neral, were detected in fish soup with added ginger and thus remained in the solution even after boiling. Similarly, 2-propen-1-ol and three sulfur compounds (allyl sulfide, diallyl disulfide, and diallyl trisulfide) present in raw garlic, were present in trace amounts in the boiled garlic solution, but were present in considerably larger amounts in the boiled fish solution with garlic or garlic plus ginger. In conclusion, the effect of adding spices on the volatile profile of grass carp soup can be attributed to the dissolution of flavor volatiles mainly derived from raw spices into the solution, with few additional volatiles being formed during boiling. In addition, boiling previously fried grass carp with spices led to enhanced volatile levels compared to boiled spice solutions.

[The Interaction of Oil Microcapsule Wall Materials between Whey Protein and Acacia].

The interaction between whey protein and acacia which were used as wall material was studied on the formation of the oils microcapsules by the FTIR Spectroscopy and Computer Aided Analysis. The results indicated that whey protein changed obviously in amide A and amide I by high pressured homogenization and spray-drying. The amide A moved from 3 406.5 cm(-1) to 3 425.4 cm(-1) which was possibly due to covalent cross-linking between whey protein and acacia. Furthermore the amide I moved from 1 648.6 cm(-1) to 1 654.7 cm(-1) for intramolecular hydrogen bonding of protein had been weaken. After Gaussian fitting on amide I , it was found that the content of secondary structure of α-helix content and ß-folding in whey protein reduced from 19.55% to 17.50% and from 30.59% to 25.63%, respectively. This suggests that protein intramolecular hydrogen bonding force was abated, resulting in abating the rigid structure of the protein molecules and enhancing of the toughness structure. The protein molecules showed some flexibility. The result of SDS-PAGE electrophoresis showed that whey protein--gum Arabic complexes produced covalent products in larger molecular weight. During the spray-drying process, covalent cross-linking produced between whey protein and gum Arabic which improved emulsifying activity of the complex whey protein and gum Arabic produced covalent cross-linking and improved the complex emulsifying activity. Observing the surface structure of the fish oil microcapsule by SEM, the compound of whey protein and acacia as wall material was proved better toughness, less micropore, and more compact structure.

Microwave heating enhances antioxidant and emulsifying activities of ovalbumin glycated with glucose in solid-state.

The aim of this study was to characterize the properties of ovalbumin (OVA) after glycated with glucose under microwave heating. For this purpose, microwave at 480 and 640 W power levels were used for heating the OVA-glucose system in solid-state for 0, 5, 10, 15, 20 and 25 min, respectively. The results indicated that the protein molecular weight was increased after glycated with glucose under microwave treatment, the pH of the system was decreased with the increase of microwave treatment power and time, while the UV absorbance, browning intensity, antioxidant activities as well as the emulsifying activity and emulsion stability of the Maillard reaction products (MRPs) were increased in according with the raise of microwave treatment power and time. The reaction time of microwave treatment is much shorter than those using traditional methods, suggesting that microwave irradiation is a novel and efficient approach to promote Maillard reaction (MR) in dry state and improve protein antioxidant and functional properties.

Physico-chemical properties of gelatin from bighead carp (Hypophthalmichthys nobilis) scales by ultrasound-assisted extraction.

In this study, gelatin was extracted from bighead carp (Hypophthalmichthys nobilis) scales by water bath (WB) and ultrasound bath (UB) at 60 °C for 1 h, 3 h and 5 h, named WB1, WB3, WB5, UB1, UB3 and UB5, respectively. The physicochemical properties of gelatin were investigated. The result indicated that gelatin extracted from bighead carp scales had a high protein content (84.15 ~ 91.85 %) with moisture (7.11 ~ 13.65 %), low ash content (0.31 ~ 0.97 %). All extracted gelatin contained α-and ß-chains as the predominant components. Gelatin extracted by UB obtained much higher yield (30.94-46.67 %) than that of WB (19.15-36.39 %). More voids and less sheets of gelatin structure were observed, when the gelatin was extracted by UB for longer time. Gelatin of UB-assisted extraction normally exhibited lower gel strength and melting points than that of WB, which may be resulted from the protein degradation reflected by the FTIR spectra and higher free amino group content. However, there was no significant difference between WB1 and UB1. Therefore, the ultrasound assisted extraction in a short time was a promising method to enhance the yield and obtain gelatin with high quality.